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Sample records for situ stabilization grouts

  1. Latex-modified grouts for in-situ stabilization of buried transuranic/mixed waste

    International Nuclear Information System (INIS)

    Allan, M.L.

    1996-06-01

    The Department of Applied Science at Brookhaven national Laboratory was requested to investigate latex-modified grouts for in-situ stabilization of buried TRU/mixed waste for INEL. The waste exists in shallow trenches that were backfilled with soil. The objective was to formulate latex-modified grouts for use with the jet grouting technique to enable in-situ stabilization of buried waste. The stabilized waste was either to be left in place or retrieved for further processing. Grouting prior to retrieval reduces the potential release of contaminants. Rheological properties of latex-modified grouts were investigated and compared with those of conventional neat cement grouts used for jet grouting

  2. Field application of innovative grouting agents for in situ stabilization of buried waste sites

    International Nuclear Information System (INIS)

    Loomis, G.G.; Farnsworth, R.K.

    1997-01-01

    This paper presents field applications for two innovative grouting agents that were used to in situ stabilize buried waste sites, via jet grouting. The two grouting agents include paraffin and a proprietary iron oxide based cement grout called TECT. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory (INEL). The field demonstrations were performed at the INEL in an area referred to as the Cold Test Pit, which is adjacent to the INEL Radioactive Waste Management Complex (RWMC). At the RWMC, 56,000 m 3 of transuranic (TRU) waste is co-mingled with over 170,000 m 3 of soil in shallow land burial. Improving the confinement of this waste is one of the options for final disposition of this waste. Using jet-grouting technology to inject these materials into the pore spaces of buried waste sites results in the creation of buried monolithic waste forms that simultaneously protect the waste from subsidence, while eliminating the migratory potential of hazardous and radioactive contaminants in the waste

  3. In situ grouting of buried transuranic waste

    International Nuclear Information System (INIS)

    Spalding, B.P.; Lee, S.Y.

    1987-01-01

    This task is a demonstration and evaluation of the in situ hydrologic stabilization of buried transuranic waste at a humid site via grout injection. Two small trenches, containing buried transuranic waste, were filled with 34,000 liters of polyacrylamide grout. Initial field results have indicated that voids within the trenches were totally filled by the grout and that the intratrench hydraulic conductivity was reduced to below field-measurable values. The grout was also completely contained within the two trenches as no grout constituents were observed in the 12 perimeter ground water monitoring wells. Polyacrylamide grout was selected for field demonstration over polyacrylate grout because of its superior performance in laboratory degradation studies. Also supporting the selection of polyacrylamide was the difficulty of controlling the set time of the acrylate polymerization process in the presence of potassium ferricyanide. Based on preliminary degradation monitoring, polyacrylamide was estimated to have a microbiological half-life of 115 years in the test soil. However, this calculated value is likely to be conservatively low because microbial degradation of the grout set accelerator or residual monomer may be contributing most to the measured microbial respiration. Addition work, using 14 C-labeled acrylate and acrylamide grouts, is being carried out to more accurately estimate the grouts' microbiological half-life

  4. Grout performance in support of in situ stabilization/solidification of the GAAT tank sludges

    International Nuclear Information System (INIS)

    Spence, R.D.; Kauschinger, J.L.

    1997-05-01

    The Gunite trademark and associated tanks (GAATs) were constructed at ORNL between 1943 and 1951 and were used for many years to collect radioactive and chemical wastes. These tanks are currently inactive. Varying amounts of the sludge were removed and disposed of through the Hydrofracture Program. Thus, some tanks are virtually empty, while others still contain significant amounts of sludge and supernatant. In situ grouting of the sludges in the tanks using multi-point injection (MPI trademark), a patented, proprietary technique, is being investigated as a low-cost alternative to (1) moving the sludges to the Melton Valley Storage Tanks (MVSTs) for later solidification and disposal, (2) ex situ grouting of the sludges followed by either disposal back in the tanks or containerizing and disposal elsewhere, and (3) vitrification of the sludges. The paper discusses the chemical characteristics of the GAATs and the type of chemical surrogate that was used during the leachability tests. This is followed by the experimental work, which, consisted of scope testing and sensitivity testing. The scope testing explored the rheology of the proposed jetting slurries and the settling properties of the proposed grouts using sand-water mixes for the wet sludge. After establishing a jetting slurry and grout with an acceptable rheology and settling properties, the proposed in situ grout formulation was subjected to sensitivity testing for variations in the formulation

  5. In situ grouting of low-level burial trenches with a cement-based grout

    International Nuclear Information System (INIS)

    Francis, C.W.; Spalding, B.P.

    1991-01-01

    A restoration technology being evaluated for use in the closure of one of the low-level radwaste burial grounds at Oak Ridge National Laboratory (ORNL) is trench stabilization using a cement-based grout. To demonstrate the applicability and effectiveness of this technology, two interconnecting trenches in Solid Waste Storage Area 6 (SWSA 6) were selected as candidates for in situ grouting with a particulate grout. The primary objective was to demonstrate the increased trench stability and decreased potential for leachate migration following in situ injection of a particulate grout into the waste trenches. Stability against trench subsidence is a critical issue. 7 refs., 3 figs., 5 tabs

  6. In situ grouting of buried transuranic waste with polyacrylamide

    International Nuclear Information System (INIS)

    Spalding, B.P.; Lee, S.Y.; Farmer, C.D.; Hyder, L.K.; Supaokit, P.

    1987-01-01

    This project is a demonstration and evaluation of the in situ hydrologic stabilization of buried transuranic waste at a humid site via grout injection. Two small trenches, containing buried transuranic waste, were filled with 34.000 L of polyacrylamide grout. Initial field results have indicated that voids within the trenches were totally filled by the grout and that the intratrench hydraulic conductivity was reduced to below field-measurable values. No evidence of grout constituents were observed in twelve perimeter groundwater monitoring wells indicating that grout was contained completely within the two trenches. Polyacrylamide grout was selected for field demonstration over the polyacrylate grout due to its superior performance in laboratory degradation studies. Also supporting the selection of polyacrylamide was the difficulty in controlling the set time of the acrylate polymerization. Based on preliminary degradation monitoring, the polyacrylamide was estimated to have a microbiological half-life of 362 years in the test soil. 15 refs., 9 figs., 12 tabs

  7. In situ grouting of buried transuranic waste with polyacrylamide

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, B.P.; Lee, S.Y.; Farmer, C.D.; Hyder, L.K.; Supaokit, P.

    1987-01-01

    This project is a demonstration and evaluation of the in situ hydrologic stabilization of buried transuranic waste at a humid site via grout injection. Two small trenches, containing buried transuranic waste, were filled with 34.000 L of polyacrylamide grout. Initial field results have indicated that voids within the trenches were totally filled by the grout and that the intratrench hydraulic conductivity was reduced to below field-measurable values. No evidence of grout constituents were observed in twelve perimeter groundwater monitoring wells indicating that grout was contained completely within the two trenches. Polyacrylamide grout was selected for field demonstration over the polyacrylate grout due to its superior performance in laboratory degradation studies. Also supporting the selection of polyacrylamide was the difficulty in controlling the set time of the acrylate polymerization. Based on preliminary degradation monitoring, the polyacrylamide was estimated to have a microbiological half-life of 362 years in the test soil. 15 refs., 9 figs., 12 tabs.

  8. In situ grouting of low-level burial trenches with a cement-based grout

    International Nuclear Information System (INIS)

    Francis, C.W.; Spalding, B.P.

    1991-01-01

    A restoration technology being evaluated for use in the closure of one of the low-level radwaste burial grounds at Oak Ridge National Laboratory (ORNL) is trench stabilization using a cement-based grout. To demonstrate the applicability and effectiveness of this technology, two interconnecting trenches in Solid Waste Storage Area 6 (SWSA 6) were selected as candidates for in situ grouting with a particulate grout. The primary objective was to demonstrate the increased trench stability and decreased potential for leachate migration following in situ injection of a particulate grout into the waste trenches. Stability against trench subsidence is a critical issue. After grouting, soil-penetration tests disclosed that stability had been improved greatly. For example, refusal (defined as > 100 blows to penetrate 1 ft) was encountered in 17 of the 22 tests conducted within the trench area. Mean refusal depths for the two trenches were 3.5 and 2.6 m. Stability of the trench was significantly better than pregrout conditions, and at depths > 2.4 m, the stability was very near that observed in the native soil formation outside the trench. Tests within the trench showed lower stability within this range probably because of the presence of intermediate-sized soil voids (formed during backfilling) that were too small to be penetrated and filled by the conventional cement grout formulation. Hydraulic conductivity within the trench remained very high (>0.1 cm/s) and significantly greater than outside the trench. Postgrout air pressurization tests also revealed a large degree of intervoid linkage within and between the two trenches. To effectively reduce hydraulic conductivity and to develop stability within the upper level of the trench, injection of a clay/microfine cement grout into the upper level of the grouted trench is planned

  9. In situ grouting of low-level burial trenches with a cement-based grout at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Francis, C.W.; Spence, R.D.; Tamura, T.; Spalding, B.P.

    1993-01-01

    A technology being evaluated for use in the closure of one of the low-level radwaste burial grounds at ORNL is trench stabilization using a cement-based grout. To demonstrate the applicability and effectiveness of this technology, two interconnecting trenches in SWSA 6 were selected as candidates for in situ grouting with a particulate grout. The primary objective was to demonstrate the increased trench stability (characterized by trench penetration tests) and the decreased potential for leachate migration (characterized by hydraulic conductivity tests) following in situ injection of a particulate grout into the waste trenches. Stability against trench subsidence is a critical issue. For example, construction of impermeable covers to seal the trenches will be ineffectual unless subsequent trench subsidence is permanently suspended. A grout composed of 39% Type 1 Portland cement, 55.5% Class F fly ash, and 5.5% bentonite mixed at 12.5 lb/gal of water was selected. Before the trenches were grouted, the primary characteristics relating to physical stability, hydraulic conductivity, and void volume of the trenches were determined. Their physical stability was evaluated using soil-penetration tests

  10. Field demonstration of in situ grouting of radioactive solid waste burial trenches with polyacrylamide

    International Nuclear Information System (INIS)

    Spalding, B.P.; Fontaine, T.A.

    1990-01-01

    Demonstrations of in situ grouting with polyacrylamide were carried out on two undisturbed burial trenches and one dynamically compacted burial trench in Solid Waste Storage Area (SWSA) 6 at Oak Ridge National Laboratory (ORNL). The injection of polyacrylamide was achieved quite facilely for the two undisturbed burial trenches which were filled with grout, at typical pumping rates of 95 L/min, in several batches injected over several days. The compacted burial trench, however, failed to accept grout at more than 1.9 L/min even when pressure was applied. Thus, it appears that burial trenches, stabilized by dynamic compaction, have a permeability too low to be considered groutable. The water table beneath the burial trenches did not respond to grout injections indicating a lack of hydrologic connection between fluid grout and the water table which would have been observed if the grout failed to set. Because grout set times were adjusted to less than 60 min, the lack of hydrologic connection was not surprising. Postgrouting penetration testing revealed that the stability of the burial trenches was increased from 26% to 79% that measured in the undisturbed soil surrounding the trenches. In situ permeation tests on the grouted trenches indicated a significant reduction in hydraulic conductivity of the trench contents from a mean of 2.1 x 10 -3 to 1.85 x 10 -5 cm/s. Preliminary observations indicated that grouting with polyacrylamide is an excellent method for both improved stability and hydrologic isolation of radioactive waste and its incidental hazardous constituents

  11. Grout performance in support of in situ grouting of the TH4 tank sludge

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, R.D.; Kauschinger, J.L.; Spence, R.D.

    1999-04-01

    The cold demonstration test proved that less water was required to pump the in situ grout formulation than had been previously tested in the laboratory. The previous in situ grout formulation was restandardized with the same relative amounts of dry blend ingredients, albeit adding a fluidized admixture, but specifying less water for the slurry mix that must by pumped through the nozzles at high pressure. Also, the target GAAT tank for demonstrating this is situ grouting technique has been shifted to Tank TH4. A chemical surrogate sludge for TH4 was developed and tested in the laboratory, meeting expectations for leach resistance and strenght at 35 wt % sludge loading. It addition, a sample of hot TH4 sludge was also tested at 35 wt % sludge loading and proved to have superior strength and leach resistance compared with the surrogate test.

  12. Florida Sinkholes and Grout Injection Stabilization

    Directory of Open Access Journals (Sweden)

    Charles Hunt Griffith II

    2014-09-01

    Full Text Available Florida has a major problem when it comes to sinkholes. These sinkholes can become very hazardous to people, homes, and to the landscape as a whole. Florida sits on a carbonate platform which is highly indicative of sinkholes. There are three main types of sinkholes which occur in Florida: dissolution, cover subsidence, and cover collapse. I will compare these types of sinkholes to the underlying formation beneath Florida to see if there is a connection between the types of sinkholes that occur. I will also create a 3D model of grout injection stabilization and calculate its volume to compare to the actual volume placed under the house. This information will help inform and bring attention to the problem in Florida and in turn, may help alleviate the problem if we can understand what causes these sinkholes. The 3D model may help engineering companies become more efficient in predicting the projected amount of volume to stabilize a house that may be in danger.

  13. Task plan to evaluate the effectiveness of in situ grouting of an ORNL waste burial trench with a cement-based grout

    International Nuclear Information System (INIS)

    Francis, C.W.

    1991-11-01

    This task will demonstrate the feasibility of using an in situ grouting technique with a particulate-grout formulation as a closure action to stabilize waste trenches in Solid Waste Storage Area (SWSA) 6. It also supports technology development for closure of other SWSAs. A particulate grout will be formulated using cement-bentonite and fly ash from a coal-fired power plant. The grout solids will be dry-blended, mixed with water, and injected (using ∼5 to 10 lb/in. 2 pressure) into five injection wells per trench. After 28 days for setting, soil penetration resistance and hydraulic conductivity measurements will be repeated for comparison to pregrouting measurements. The primary objective of this task is to demonstrate the feasibility and effectiveness of the in situ injection of a particulate grout into waste burial trenches. Effectiveness is defined here as increased trenched stability (characterized by trench penetration resistance tests) and decreased potential for leachate migration (characterized by hydraulic conductivity tests)

  14. In-Situ Grouting Treatability Study for the Idaho National Engineering and Environmental Laboratory Subsurface Disposal Area-Transuranic Pits and Trenches

    International Nuclear Information System (INIS)

    Loomis, G. G.; Jessmore, J. J.; Sehn, A. L.; Miller, C. M.

    2002-01-01

    At the Idaho National Engineering and Environmental Laboratory (INEEL), a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) treatability study is being performed to examine the technology of in situ grouting for final in situ disposal of buried mixed transuranic (TRU) waste. At the INEEL, there is over 56,000 cubic meters of waste commingled with a similar amount of soil in a shallow (3-5 m) land burial referred to as Waste Area Group 7-13/14. Since this buried waste has been declared on the National Priorities List under CERCLA, it is being managed as a superfund site. Under CERCLA, options for this waste include capping and continued monitoring, retrieval and ex situ management of the retrieved waste, in situ stabilization by vitrification or grouting, in situ thermal dissorption, or some combination of these options. In situ grouting involves injecting grout at high pressures (400 bars) directly into the waste to create a solid monolith. The in situ grouting process is expected to both stabilize the waste against subsidence and provide containment against migration of waste to the Snake River Plain Aquifer lying 150-200 m below the waste. The treatability study involves bench testing, implementability testing, and field testing. The bench testing was designed to pick three grouts from six candidate grouts for the implementability field testing in full scale which were designed to down-select from those three grouts to one grout for use in a full-scale field demonstration of the technology in a simulated test pit. During the bench testing, grouts were evaluated for durability using American Nuclear Society 16.1 Leach Protocol as well as evaluating the effect on physical parameters such as hydraulic conductivity and compressive strength due to the presence of interferences such as soil, organic sludge, and nitrate salts. During full-scale implementability testing, three grouts were evaluated for groutability and monolith formation

  15. In-situ grouting of uranium-mill-tailings piles: an assessment

    International Nuclear Information System (INIS)

    Tamura, T.; Boegly, W.J. Jr.

    1983-05-01

    Passage in 1978 of the Uranium Mill Tailings Radiation Control Act (UMTRCA) initiated a program of remedial action for 22 existing mill tailings piles generated in the period 1940 to 1970 as part of the nation's defense and nuclear power programs. The presence of these piles poses potential health and environmental contamination concerns. Possible remedial actions proposed include multilayer covers over the piles to reduce water infiltration, reduce radon gas releases, and reduce airborne transport of tailings fines. In addition, suggested remedial actions include (1) the use of liners to prevent groundwater contamination by leachates from the piles and (2) chemical stabilization of the tailings to retain the radioactive and nonradioactive sources of contamination. Lining of the piles would normally be applicable only to piles that are to be moved from their present location such that the liner could be placed between the tailings and the groundwater. However, by using civil engineering techniques developed for grouting rocks and soils for strength and water control, it may be possible to produce an in situ liner for piles that are not to be relocated. The Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project Office requested that ORNL assess the potential application of grouting as a remedial action. This report examines the types of grouts, the equipment available, and the costs, and assesses the possibility of applying grouting technology as a remedial action alternative for uranium mill tailings piles

  16. In-situ grouting of uranium-mill-tailings piles: an assessment

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, T.; Boegly, W.J. Jr.

    1983-05-01

    Passage in 1978 of the Uranium Mill Tailings Radiation Control Act (UMTRCA) initiated a program of remedial action for 22 existing mill tailings piles generated in the period 1940 to 1970 as part of the nation's defense and nuclear power programs. The presence of these piles poses potential health and environmental contamination concerns. Possible remedial actions proposed include multilayer covers over the piles to reduce water infiltration, reduce radon gas releases, and reduce airborne transport of tailings fines. In addition, suggested remedial actions include (1) the use of liners to prevent groundwater contamination by leachates from the piles and (2) chemical stabilization of the tailings to retain the radioactive and nonradioactive sources of contamination. Lining of the piles would normally be applicable only to piles that are to be moved from their present location such that the liner could be placed between the tailings and the groundwater. However, by using civil engineering techniques developed for grouting rocks and soils for strength and water control, it may be possible to produce an in situ liner for piles that are not to be relocated. The Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project Office requested that ORNL assess the potential application of grouting as a remedial action. This report examines the types of grouts, the equipment available, and the costs, and assesses the possibility of applying grouting technology as a remedial action alternative for uranium mill tailings piles.

  17. Solidification/stabilization of technetium in cement-based grouts

    International Nuclear Information System (INIS)

    Gilliam, T.M.; Bostick, W.D.; Spence, R.D.; Shoemaker, J.L.

    1990-01-01

    Mixed low-level radioactive and chemically hazardous process treatment wastes from the Portsmouth Gaseous Diffusion Plant are stabilized by solidification in cement-based grouts. Conventional portland cement and fly ash grouts have been shown to be effective for retention of hydrolyzable metals (e.g., lead, cadmium, uranium and nickel) but are marginally acceptable for retention of radioactive Tc-99, which is present in the waste as the highly mobile pertechnate anion. Addition of ground blast furnace slag to the grout is shown to reduce the leachability of technetium by several orders of magnitude. The selective effect of slag is believed to be due to its ability to reduce Tc(VII) to the less soluble Tc(IV) species. 12 refs., 4 tabs

  18. Initial formulation results for in situ grouting of a waste trench at ORNL Site No. 6

    International Nuclear Information System (INIS)

    Tallent, O.K.; McDaniel, E.W.; Spence, R.D.; Godsey, T.T.

    1987-01-01

    An investigation is being conducted by the Chemical Technology Division to assist the Environmental Sciences Division in developing a grout formulation for use in testing in situ grouting in a waste trench at ORNL Site 6. This final report satisfies the milestone of Subtack 12 entitled, ''Low Level Waste (LLW) Trench Grouting Assessment,'' which was initially issued as RAP-86-7, December 31, 1985. Grouts prepared from dry-solid blends containing Type I Portland cement, ASTM Class C or Class F fly ash, and bentonite, mixed water at ratios of 10 to 15 lb/gal, were evaluated. The grouts prepared with ASTM Class C fly ash exhibited significantly better properties than those prepared with ASTM Class F fly ash. The grouts containing ASTM Class C fly ash satisfy tentative performance criteria for the project. 8 refs., 7 tabs

  19. Grouting design for slope stability of kedung uling earthfill dam

    Directory of Open Access Journals (Sweden)

    Najib

    2018-01-01

    Full Text Available Kedung Uling earthfill dam locates at Wonogiri Regency, Central Java, Indonesia. The dam encountered sliding and settlement at the embankment wall. To minimize sliding and settlement and to optimize the dam, both field investigation and laboratory tests have been proceeded for slope stability analysis and remedial embankment wall. Soil and rock investigation around the dam, which is followed by 10 core drillings, have been conducted. Laboratory tests such as direct shear and index properties have also been carried on. The results were further used for dam slope stability model using slide 6.0 and were used to analyzed factor of safety (FS of Kedunguling dam. 10 conditions of dam were simulated and strengthening body of dam with grouting was designed. The results showed two conditions, which are condition of maximum water level with and without earthquake at downstream, were unsatisfy Indonesia National Standard (SNI for building and infrastructure. These conditions can be managed by using grouting for increasing stabilization of embankment wall. By setting up grouting, factor of safety increases and meet the SNI standard requirement.

  20. BLENDED CALCIUM ALUMINATE-CALCIUM SULFATE CEMENT-BASED GROUT FOR P-REACTOR VESSEL IN-SITU DECOMMISSIONING

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Stefanko, D.

    2011-03-10

    The objective of this report is to document laboratory testing of blended calcium aluminate - calcium hemihydrate grouts for P-Reactor vessel in-situ decommissioning. Blended calcium aluminate - calcium hemihydrate cement-based grout was identified as candidate material for filling (physically stabilizing) the 105-P Reactor vessel (RV) because it is less alkaline than portland cement-based grout which has a pH greater than 12.4. In addition, blended calcium aluminate - calcium hemihydrate cement compositions can be formulated such that the primary cementitious phase is a stable crystalline material. A less alkaline material (pH {<=} 10.5) was desired to address a potential materials compatibility issue caused by corrosion of aluminum metal in highly alkaline environments such as that encountered in portland cement grouts [Wiersma, 2009a and b, Wiersma, 2010, and Serrato and Langton, 2010]. Information concerning access points into the P-Reactor vessel and amount of aluminum metal in the vessel is provided elsewhere [Griffin, 2010, Stefanko, 2009 and Wiersma, 2009 and 2010, Bobbitt, 2010, respectively]. Radiolysis calculations are also provided in a separate document [Reyes-Jimenez, 2010].

  1. Use of a Paraffin Based Grout to Stabilize Buried Beryllium and Other Wastes

    International Nuclear Information System (INIS)

    Gretchen Matthern; Duane Hanson; Neal Yancey; Darrell Knudson

    2005-01-01

    The long term durability of WAXFIXi, a paraffin based grout, was evaluated for in situ grouting of activated beryllium wastes in the Subsurface Disposal Area (SDA), a radioactive landfill at the Radioactive Waste Management Complex, part of the Idaho National Laboratory (INL). The evaluation considered radiological and biological mechanisms that could degrade the grout using data from an extensive literature search and previous tests of in situ grouting at the INL. Conservative radioactive doses for WAXFIX were calculated from the ''hottest'' (i.e., highest-activity) Advanced Test Reactor beryllium block in the SDA.. These results indicate that WAXFIX would not experience extensive radiation damage for many hundreds of years. Calculation of radiation induced hydrogen generation in WAXFIX indicated that grout physical performance should not be reduced beyond the effects of radiation dose on the molecular structure. Degradation of a paraffin-based grout by microorganisms in the SDA is possible and perhaps likely, but the rate of degradation will be at a slower rate than found in the literature reviewed. The calculations showed the outer 0.46 m (18 in.) layer of each monolith, which represents the minimum expected distance to the beryllium block, was calculated to require 1,000 to 3,600 years to be consumed. The existing data and estimations of biodegradation and radiolysis rates for WAXFIX/paraffin do not indicate any immediate problems with the use of WAXFIX for grouting beryllium or other wastes in the SDA

  2. Literature review of stabilization/solidification of volatile organic compounds and the implications for Hanford grouts

    International Nuclear Information System (INIS)

    Spence, R.D.; Osborne, S.C.

    1993-09-01

    A literature review was conducted on the stabilization/solidification of volatile organic compounds (VOCs). Based on this literature, it is likely that the limestone-containing grout will not permanently immobilize VOCs and that no presently available additives can guarantee permanent immobilization. The Westinghouse hanford company grout may be fairly effective at retarding aqueous leaching of VOCs, and commercial additives can improve this performance. Significant VOC losses do occur during stabilization/solidification, and the high temperatures of the Westinghouse Hanford Company waste and grout should exacerbate this problem. In fact, these high temperatures raise doubts about the presence of VOCs in the double-shell tanks supernates

  3. Use of a Paraffin Based Grout to Stabilize Buried Beryllium and Other Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Gretchen Matthern; Duane Hanson; Neal Yancey; Darrell Knudson

    2005-12-01

    The long term durability of WAXFIXi, a paraffin based grout, was evaluated for in situ grouting of activated beryllium wastes in the Subsurface Disposal Area (SDA), a radioactive landfill at the Radioactive Waste Management Complex, part of the Idaho National Laboratory (INL). The evaluation considered radiological and biological mechanisms that could degrade the grout using data from an extensive literature search and previous tests of in situ grouting at the INL. Conservative radioactive doses for WAXFIX were calculated from the "hottest" (i.e., highest-activity) Advanced Test Reactor beryllium block in the SDA.. These results indicate that WAXFIX would not experience extensive radiation damage for many hundreds of years. Calculation of radiation induced hydrogen generation in WAXFIX indicated that grout physical performance should not be reduced beyond the effects of radiation dose on the molecular structure. Degradation of a paraffin-based grout by microorganisms in the SDA is possible and perhaps likely, but the rate of degradation will be at a slower rate than found in the literature reviewed. The calculations showed the outer 0.46 m (18 in.) layer of each monolith, which represents the minimum expected distance to the beryllium block, was calculated to require 1,000 to 3,600 years to be consumed. The existing data and estimations of biodegradation and radiolysis rates

  4. In-situ containment and stabilization of buried waste

    International Nuclear Information System (INIS)

    Allan, M.L.; Kukacka, L.E.

    1993-10-01

    In FY 1993 research continued on development and testing of grout materials for in-situ containment and stabilization of buried waste. Specifically, the work was aimed at remediation of the Chemical Waste Landfill (CWL) at Sandia National Laboratories (SNL) in Albuquerque, New Mexico as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). The work on grouting materials was initiated in FY 1992 and the accomplishments for that year are documented in the previous annual report (Allan, Kukacka and Heiser, 1992). The remediation plan involves stabilization of the chromium plume, placement of impermeable vertical and horizontal barriers to isolate the landfill and installation of a surface cap. The required depth of subsurface barriers is approximately 33 m (100 ft). The work concentrated on optimization of grout formulations for use as grout and soil cement barriers and caps. The durability of such materials was investigated, in addition to shrinkage cracking resistance, compressive and flexural strength and permeability. The potential for using fibers in grouts to control cracking was studied. Small scale field trials were conducted to test the practicality of using the identified formulations and to measure the long term performance. Large scale trials were conducted at Sandia as part of the Subsurface Barrier Emplacement Technology Program. Since it was already determined in FY 1992 that cementitious grouts could effectively stabilize the chromium plume at the CWL after pre-treatment is performed, the majority of the work was devoted to the containment aspect

  5. Laboratory stabilization/solidification of surrogate and actual mixed-waste sludge in glass and grout

    International Nuclear Information System (INIS)

    Spence, R.D.; Gilliam, T.M.; Mattus, C.H.; Mattus, A.J.

    1998-01-01

    Grouting and vitrification are currently the most likely stabilization/solidification technologies for mixed wastes. Grouting has been used to stabilize and solidify hazardous and low-level waste for decades. Vitrification has long been developed as a high-level-waste alternative and has been under development recently as an alternative treatment technology for low-level mixed waste. Laboratory testing has been performed to develop grout and vitrification formulas for mixed-waste sludges currently stored in underground tanks at Oak Ridge National Laboratory (ORNL) and to compare these waste forms. Envelopes, or operating windows, for both grout and soda-lime-silica glass formulations for a surrogate sludge were developed. One formulation within each envelope was selected for testing the sensitivity of performance to variations (±10 wt%) in the waste form composition and variations in the surrogate sludge composition over the range previously characterized in the sludges. In addition, one sludge sample of an actual mixed-waste tank was obtained, a surrogate was developed for this sludge sample, and grout and glass samples were prepared and tested in the laboratory using both surrogate and the actual sludge. The sensitivity testing of a surrogate tank sludge in selected glass and grout formulations is discussed in this paper, along with the hot-cell testing of an actual tank sludge sample

  6. Materials testing for in situ stabilization treatability study of INEEL mixed wastes soils

    International Nuclear Information System (INIS)

    Heiser, J.; Fuhrmann, M.

    1997-09-01

    This report describes the contaminant-specific materials testing phase of the In Situ Stabilization Comprehensive Environment Response, Compensation, and Liability Act (CERCLA) Treatability Study (TS). The purpose of materials testing is to measure the effectiveness of grouting agents to stabilize Idaho National Engineering and Environmental Laboratory (INEEL) Acid Pit soils and select a grout material for use in the Cold Test Demonstration and Acid Pit Stabilization Treatability Study within the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex (RWMC). Test results will assist the selecting a grout material for the follow-on demonstrations described in Test Plan for the Cold Test Demonstration and Acid Pit Stabilization Phases of the In Situ Stabilization Treatability Study at the Radioactive Waste Management Complex

  7. Weldon Spring, Missouri, Raffinate Pits 1, 2, 3, and 4: Preliminary grout development screening studies for in situ waste immobilization

    International Nuclear Information System (INIS)

    McDaniel, E.W.; Gilliam, T.M.; Dole, L.R.; West, G.A.

    1987-04-01

    Results of Oak Ridge National Laboratory's initial support program to develop a preliminary grout formula to solidify in situ the Weldon Spring waste are presented. The screening study developed preliminary formulas based on a simulated composite waste and then tested the formulas on actual waste samples. Future data needs are also discussed. 1 ref., 6 figs., 9 tabs

  8. Grout and glass performance in support of stabilization/solidification of ORNL tank sludges

    International Nuclear Information System (INIS)

    Spence, R.D.; Mattus, C.H.; Mattus, A.J.

    1998-09-01

    Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) and Bethel Valley Evaporator Storage Tanks (BVEST) pending treatment for disposal. In addition, some sludges and supernatants also requiring treatment remain in two inactive tank systems: the gunite and associated tanks (GAAT) and the old hydrofracture (OHF) tank. The waste consists of two phases: sludge and supernatant. The sludges contain a high amount of radioactivity, and some are classified as TRU sludges. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough to be defined as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste. Grouting and vitrification are currently two likely stabilization/solidification alternatives for mixed wastes. Grouting has been used to stabilize/solidify hazardous and low-level radioactive waste for decades. Vitrification has been developed as a high-level radioactive alternative for decades and has been under development recently as an alternative disposal technology for mixed waste. The objective of this project is to define an envelope, or operating window, for grout and glass formulations for ORNL tank sludges. Formulations will be defined for the average composition of each of the major tank farms (BVEST/MVST, GAAT, and OHF) and for an overall average composition of all tank farms. This objective is to be accomplished using surrogates of the tank sludges with hot testing of actual tank sludges to check the efficacy of the surrogates

  9. Idaho Chemical Processing Plant low-level waste grout stabilization development program FY-96 status report

    International Nuclear Information System (INIS)

    Herbst, A.K.

    1996-09-01

    The general purpose of the Grout Stabilization Development Program is to solidify and stabilize the liquid low-level wastes (LLW) generated at the Idaho Chemical Processing Plant (ICPP). It is anticipated that LLW will be produced from the following: (1) chemical separation of the tank farm high-activity sodium-bearing waste; (2) retrieval, dissolution, and chemical separation of the aluminum, zirconium, and sodium calcines; (3) facility decontamination processes; and (4) process equipment waste. The main tasks completed this fiscal year as part of the program were chromium stabilization study for sodium-bearing waste and stabilization and solidification of LLW from aluminum and zirconium calcines. The projected LLW will be highly acidic and contain high amounts of nitrates. Both of these are detrimental to Portland cement chemistry; thus, methods to precondition the LLW and to cure the grout were explored. A thermal calcination process, called denitration, was developed to solidify the waste and destroy the nitrates. A three-way blend of Portland cement, blast furnace slag, and fly ash was successfully tested. Grout cubes were prepared at various waste loadings to maximize loading while meeting compressive strength and leach resistance requirements. For the sodium LLW, a 25% waste loading achieves a volume reduction of 3.5 and a compressive strength of 2,500 pounds per square inch while meeting leach, mix, and flow requirements. It was found that the sulfur in the slag reduces the chromium leach rate below regulatory limits. For the aluminum LLW, a 15% waste loading achieves a volume reduction of 8.5 and a compressive strength of 4,350 pounds per square inch while meeting leach requirements. Likewise for zirconium LLW, a 30% waste loading achieves a volume reduction of 8.3 and a compressive strength of 3,570 pounds per square inch

  10. Study of furfural-urea grout

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    An analysis of raw materials, formulation and performance of furfural-urea grout is given. Characteristics of the grout slurry, mechanism of stabilization and examples of shaft sinking with grouting in quicksand are summarized.

  11. In-situ containment and stabilization of buried waste: Annual report FY 1994

    International Nuclear Information System (INIS)

    Allan, M.L.; Kukacka, L.E.

    1994-10-01

    The two landfills of specific interest are the Chemical Waste Landfill (CWL) and the Mixed Waste Landfill (MWL), both located at Sandia National Laboratory. The work is comprised of two subtasks: (1) In-Situ Barriers and (2) In-Situ Stabilization of Contaminated Soils. The main environmental concern at the CWL is a chromium plume resulting from disposal of chromic acid and chromic sulfuric acid into unlined pits. This program has investigated means of in-situ stabilization of chromium contaminated soils and placement of containment barriers around the CWL. The MWL contains a plume of tritiated water. In-situ immobilization of tritiated water with cementitious grouts was not considered to be a method with a high probability of success and was not pursued. This is discussed further in Section 5.0. Containment barriers for the tritium plume were investigated. FY 94 work focused on stabilization of chromium contaminated soil with blast furnace slag modified grouts to bypass the stage of pre-reduction of Cr(6), barriers for tritiated water containment at the MWL, continued study of barriers for the CWL, and jet grouting field trials for CWL barriers at an uncontaminated site at SNL. Cores from the FY 93 permeation grouting field trails were also tested in FY 94

  12. In situ grouting of a low-level radioactive waste trench

    International Nuclear Information System (INIS)

    Spence, R.D.; Godsey, T.T.; McDaniel, E.W.

    1987-11-01

    A shallow land burial trench containing low level radioactive waste was injected with a particulate grout to help control subsidence and radionuclide migration. The trench's accessible voids have been estimated at 20 vol %, and most of these voids appear to have been filled with grout. This injection was accomplished with a simple, labor intensive technique, and an inexperienced crew at an estimated cost of about $55,000. The grout costs $0.21/gal and 8081 gal was injected into the trench. 5 refs., 10 figs., 4 tabs

  13. In-situ stabilization of mixed waste contaminated soil

    International Nuclear Information System (INIS)

    Siegrist, R.L.; Cline, S.R.; Gilliam, T.M.; Conner, J.R.

    1993-01-01

    A full-scale field demonstration was conducted to evaluate in for stabilizing an inactive RCRA land treatment site at a DOE facility in Ohio. Subsurface silt and clay deposits were contaminated principally with up to 500 mg/kg of trichloroethylene and other halocarbons, but also trace to low levels of Pb, Cr, 235 U, and 99 Tc. In situ solidification was studied in three, 3.1 m diameter by 4.6 m deep columns. During mixing, a cement-based grout was injected and any missions from the mixed region were captured in a shroud and treated by filtration and carbon adsorption. During in situ processing, operation and performance parameters were measured, and soil cores were obtained from a solidified column 15 months later. Despite previous site-specific treatability experience, there were difficulties in selecting a grout with the requisite treatment agents amenable to subsurface injection and at a volume adequate for distribution throughout the mixed region while minimizing volume expansion. observations during the demonstration revealed that in situ solidification was rapidly accomplished (e.g., >90 m 3 /d) with limited emissions of volatile organics (i.e., -6 cm/s vs. 10 -8 cm/s). Leaching tests performed on the treated samples revealed non-detectable to acceptably low concentrations of all target contaminants

  14. In-situ stabilization of TRU/mixed waste project at the INEEL

    International Nuclear Information System (INIS)

    Milian, L.W.; Heiser, J.H.; Adams, J.W.; Rutenkroeger, S.P.

    1997-08-01

    Throughout the DOE complex, buried waste poses a threat to the environment by means of contaminant transport. Many of the sites contain buried waste that is untreated, prior to disposal, or insufficiently treated, by today's standards. One option to remedy these disposal problems is to stabilize the waste in situ. This project was in support of the Transuranic/Mixed Buried Waste - Arid Soils product line of the Landfill Focus Area, which is managed currently by the Idaho National Engineering Laboratory (BNL) provided the analytical laboratory and technical support for the various stabilization activities that will be performed as part of the In Situ Stabilization of TRU/Mixed Waste project at the INEL. More specifically, BNL was involved in laboratory testing that included the evaluation of several grouting materials and their compatibility, interaction, and long-term durability/performance, following the encapsulation of various waste materials. The four grouting materials chosen by INEL were: TECT 1, a two component, high density cementious grout, WAXFIX, a two component, molten wax product, Carbray 100, a two component elastomeric epoxy, and phosphate cement, a two component ceramic. A simulated waste stream comprised of sodium nitrate, Canola oil, and INEL soil was used in this study. Seven performance and durability tests were conducted on grout/waste specimens: compressive strength, wet-dry cycling, thermal analysis, base immersion, solvent immersion, hydraulic conductivity, and accelerated leach testing

  15. Laboratory-performance criteria for in situ waste-stabilization materials

    International Nuclear Information System (INIS)

    Shaw, P.; Weidner, J.

    1996-01-01

    The Department of Energy (DOE) Landfill Stabilization Focus Area is investigating a variety of in situ placement methods, grout materials, and characterization techniques for the stabilization of buried low-level transuranic-contaminated waste at Department of Energy sites. In situ stabilization involves underground injection or placement of substances to isolate, treat, or contain buried contaminants. Performance criteria were developed to evaluate various candidate stabilization materials for both long-term stabilization and interim stabilization or retrieval. The criteria are go/no-go, ready, and preliminary. The criterion go/no-go eliminates technologies that are not applicable for in situ treatment of buried waste. The criterion ready indicates that the technology is sufficiently developed and proven to be field demonstrated full-scale. The criterion preliminary indicates the prospective technologies to be potentially applicable to in situ buried waste stabilization, but further development is needed before the technology is ready for field-scale demonstration

  16. In situ stabilization wall for containment and hot spot retrieval

    International Nuclear Information System (INIS)

    Loomis, G.G.

    1996-01-01

    This paper presents the results of a full scale field demonstration of a in situ stabilization technology applicable to buried transuranic waste. The technology involves creating a jet grouted wall around selected regions or hot spots within a buried waste site. The resulting wall provides a barrier against further horizontal migration of the contaminants and allows vertical digging of material inside the wall, thus minimizing waste during a hot spot removal action. The demonstration involved creating a open-quotes Uclose quotes shaped wall in the interior of a full sized, simulated waste pit. The wall simulated the main features of a four sided wall. The demonstration also involved a destructive examination and a stability test for a hot spot retrieval scenario

  17. Grout testing and characterization for shallow-land burial trenches at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Tallent, O.K.; Sams, T.L.; Tamura, T.; Godsey, T.T.; Francis, C.L.; McDaniel, E.W.

    1986-10-01

    An investigation was conducted to develop grout formulations suitable for in situ stabilization of low-level and transuranic (TRU) waste in shallow-land burial trenches at Idaho National Engineering Laboratory (INEL). The acceptabilities of soil, ordinary particulate, and fine particulate grouts were evaluated based on phase separation, compressive strength, freeze/thaw, penetration resistance, rheological, water permeability, column, and other tests. Soil grouts with soil-to-cement weight ratios from 0.91 to 1.60 were found to be suitable for open trench or drum disposal. Ordinary particulate grouts containing type I,II Portland cement, class C fly ash, bentonite, water, and a fluidizer were formulated to fill large voids within the soil/waste matrix of a closed shallow-land burial trench. Fine particulate grouts containing fine (mean particle size, 9.6 m) cement and water were formulated to fill smaller voids and to establish a grout-soil barrier to prevent water intrusion into the grouted waste trench. Solution, or chemical grouts, were evaluated as possible substitutes for the fine particulate grouts

  18. In-situ grouting of the low-level radioactive waste disposal silos at ORNL's Solid Waste Storage Area Six

    International Nuclear Information System (INIS)

    Francis, C.W.; Farmer, C.D.; Stansfield, R.G.

    1993-07-01

    At Oak Ridge National Laboratory (ORNL), one method of solid low-level radioactive waste disposal has been disposed of in below-grade cylindrical concrete silos. Located in Solid Waste Storage Area 6 (SWSA 6), each silo measures 8 ft in diameter and 20 ft deep. Present day operations involve loading the silos with low-level radioactive waste and grouting the remaining void space with a particulate grout of low viscosity. Initial operations involving the disposal of wastes into the below-grade silos did not include the grouting process. Grouting was stated as a standard practice (in late 1988) after discovering that ∼75% of the silos accumulated water in the bottom of the silos in the ∼2 years after capping. Silo water (leachate) contained a wide range of types and concentrations of radionuclides. The migration of contaminated leachate out of the silo into adjoining soil and groundwater was considered to be a serious environmental concern. This report describes how a specially designed particulate-base grout was used to grout 54 silos previously filled with low-level radioactive waste. Grouting involved three steps: (1) silo preparation, (2) formulation and preparation of the grout mixture, and (3) injection of the grout into the silos. Thirty-five of the 54 silos grouted were equipped with a 3-in.-diam Polyvinyl Chloride (PVC) pipe used to monitor water levels in the silos. A method for rupturing the bottom section of these PVC wells was developed so that grout could be pumped to the bottom of those silos. Holes (2-in. diam) were drilled through the ∼18 in. thick concrete to fill the remaining 19 wells without the PVC monitoring wells. The formulation of grout injected into the silos was based on a Portland Type I cement, flyash, sand, and silica fume admixture. Compressive strength of grout delivered to SWSA6 during grouting operations averaged 1,808 lb/in 2 with a bulk density of 3,549 lb/yd 3

  19. Masonry arches retrofitted with steel reinforced grout materials: In-situ experimental tests and advanced FE simulations

    Science.gov (United States)

    Bertolesi, Elisa; Carozzi, Francesca Giulia; Milani, Gabriele; Poggi, Carlo

    2017-11-01

    The paper presents the results of a series of in-situ tests carried out on two masonry arches, one unreinforced and the other reinforced with SRG (Steel Reinforced Grout). The arches are built adopting a peculiar construction technique using common Italian bricks with dimensions 250 × 120 × 55 mm3 and 10 mm thick mortar joints. One of the two arches has been reinforced with an SRG material constituted by an inox grid embedded into a layer of lime mortar, whereas the second one is maintained unreinforced for comparison purposes. The experimental set-up is designed to apply an eccentric vertical load placed at ¼ of the span in a series of loading and unloading cycles up to the failure. The numerical analyses have been performed using a sophisticated heterogeneous micro-modeling technique, where bricks, mortar joints and the strengthening have been modeled separately. Finally, the numerical outcomes have been comparatively assessed with respect to the experimental results and the crack patterns obtained at the end of the tests, showing a satisfactory agreement in terms of the global behavior of the arches and their collapse mechanisms.

  20. Grouting mixture

    Energy Technology Data Exchange (ETDEWEB)

    Klyusov, A A; Bakshutov, V S; Kulyavtsev, V A

    1980-10-23

    A grouting mixture is proposed for low-temperature boreholes. The mixture contains cement, beta gypsum polyhydrate, and calcium chloride, so as to increase the water resistance and strength properties of expanding brick at conditions from 20 to -5/sup 0/ C, the components are in the following ratios: (by wt.-%): cement, 77.45-88.06; beta gypsum polyhydrate, 9.79-19.36; calcium chloride, 2.15-3.19. Grouting mortar for cold boreholes serves as the cement.

  1. Grout and Glass Performance in Support of Stabilization/Solidification of the MVST Tank Sludges

    Energy Technology Data Exchange (ETDEWEB)

    Gilliam, T.M.; Spence, R.D.

    1998-11-01

    Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) pending treatment for disposal. The waste separates into two phases: sludge and supematant. Some of the supematant from these tanks has been decanted, solidified into a grout, and stored for disposal as a solid low-level waste. The sludges in the tank bottoms have been accumulating ,for several years. Some of the sludges contain a high amount of gamma activity (e.g., `37CS concentration range of 0.01 3-11 MBq/g) and contain enough transuranic (TRU) radioisotopes to be classified as TRU wastes. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough in the available total constituent analysis for the MVST sludge to be classified as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste.

  2. Task plan for TARA-II compaction and grouting demonstration

    International Nuclear Information System (INIS)

    Spalding, B.P.

    1991-11-01

    This task directly supports the corrective measures evaluation for the closure of Solid Waste Storage Area (SWSA) 6 but also supports technology development for the closure of other Oak Ridge National Laboratory (ORNL) SWSAs and waste management units. Previous demonstrations have established the effectiveness of dynamic compaction and in situ grouting in stabilizing burial trenches against subsidence, which would otherwise compromise the support of infiltration barrier structures designed to protect buried waste from leaching. In situ grouting with polyacrylamide has also been demonstrated to improve the hydrologic isolation of buried waste. Both of these stabilization techniques have been demonstrated on burial trenches that are situated well above the water table and, hence, are in a chronic unsaturated moisture regime. Further demonstrations of these shallow-land burial trench stabilization techniques are necessary to establish their effectiveness and safety when applied to burial trenches that are chronically inundated with groundwater

  3. A novel natural analog in situ stabilization agent

    International Nuclear Information System (INIS)

    Shaw, P.

    1995-01-01

    This report summarizes the laboratory-scale test results on a synthetic analog of natural hematite cement for potential as an in situ treatment and stabilization agent for buried hazardous and radioactive waste. The concept is based on the principle that the ideal waste isolation materials are synthetic analogs of those natural encapsulating materials (cements), which are in equilibrium with the environment in which they occur. If equilibrium is achieved, then such materials will remain intact as long as the natural environment remains unchanged. The specific waste application is long-term stabilization of transuranic-contaminated waste pits and trenches at the Idaho National Engineering Laboratory (INEL). Six properties of the natural analog agent and resulting wasteforms are discussed to access the agent's effectiveness and implementability: hydraulic conductivity; compressive strength; mineralogy and microstructure; compatibility with possible waste materials, nitrates, machine cutting oil, and metallic iron; leachability of hazardous metals; and field application parameters. Data indicated that the iron waste encapsulation materials tested are appropriate choices for buried waste mixed with INEL soil. Iron oxide/gypsum INEL soil wasteforms have hydraulic conductivity values close to the regulatory limit. Wasteforms with soil and wastes have compressive strength greater than the regulatory minimum. Gypsum/iron oxide removes hazardous metals from solution by adsorption and would pass Toxicity Characteristic Leaching Procedure limits for most toxic metals. It appears to be chemically and physically inert with respect to the bulk of the waste materials likely to be found at INEL, and has properties conducive to jet grouting

  4. Properties of salt-saturated concrete and grout after six years in situ at the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Wakeley, L.D.; Harrington, P.T.; Weiss, C.A. Jr.

    1993-06-01

    Samples of concrete and grout were recovered from short boreholes in the repository floor at the Waste Isolation Pilot Plant more than six years after the concrete and grout were placed. Plugs from the Plug Test Matrix of the Plugging and Sealing Program of Sandia National Laboratories were overcored to include a shell of host rock. The cores were analyzed at the Waterways Experiment Station to assess their condition after six years of service, having potentially been exposed to those aspects of their service environment (salt, brine, fracturing, anhydrite, etc.) that could cause deterioration. Measured values of compressive strength and pulse velocity of both the grout and the concrete equaled or exceeded values from tests performed on laboratory-tested samples of the same mixtures at ages of one month to one year after casting. The phase assemblages had changed very little. Materials performed as intended and showed virtually no chemical or physical evidence of deterioration. The lowest values for strength and pulse velocity were measured for samples taken from the Disturbed Rock Zone, indicating the influence of cracking in this zone on the properties of enclosed seal materials. There was evidence of movement of brine in the system. Crystalline phases containing magnesium, potassium, sulfate, and other ions had been deposited on free surfaces in fractures and pilot holes. There was a reaction rim in the anhydrite immediately surrounding each recovered borehole plug, suggesting interaction between grout or concrete and host rock. However, the chemical changes apparent in this reaction rim were not reflected in the chemical composition of the adjacent concrete or grout. The grout and concrete studied here showed no signs of the deterioration found to have occurred in some parts of the concrete liner of the Waste Isolation Pilot Plant waste handling shaft

  5. Prediction and control of leachability of grouts used in low-level radioactive waste management. Final report

    International Nuclear Information System (INIS)

    Landolt, R.R.; Altschaeffl, A.G.

    1987-01-01

    The status of the following studies is reported: Uses of Grouting for Remedial Action and New Trench Stabilization; Water Movement and Grout Formulations; and Leachability of Grout Materials Used As Solidification Media. (LM)

  6. Strength of Experimental Grouts

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

     The present report describes tests carried out on 5 experimental grouts developed by BASF Construction Materials and designed for use in grouted connections of offshore windmill foundations....... The present report describes tests carried out on 5 experimental grouts developed by BASF Construction Materials and designed for use in grouted connections of offshore windmill foundations....

  7. Application of the cementitious grouts on stability and durability of semi flexible bituminous mixtures

    Science.gov (United States)

    Karami, Muhammad

    2017-11-01

    This paper describes the results of laboratory test for a high durability semi flexible bituminous mixtures (SFBM). The SFBM consists of an open asphalt structure where a high strength mortar is penetrated into the air voids of the bituminous mixtures. The SFBM combines the cement concrete's strength and the asphalt material flexibility. The objective of this study is to involve in the determination of stability and durability of SFBM by located the position of the specimen on an exposed area for 7, 90, 180 and 240 days. The performance of the SFBM was assessed using Marshall and wheel tracking apparatus. Total 18 specimens were prepared and examined for both of test. The Marshall specimens were cylindrical with dimension of 10.16 cm in diameter and 6.35 cm in high. For wheel tracking test, the specimens consisted of slabs with dimension of 30 cm in length, 30 cm in width and 5 cm in height. The results indicated that the first durability index and second durability index increased significantly. For Marshall test, the first and second durability index increased about 0.9% per day and 52.3%, respectively. However, for wheel tracking test, the first and second durability index increased about 1.9% per day and 119%, respectively.

  8. Critically evaluate techniques for the in situ testing of steel tendon grouting effectiveness as a basis for reducing fall of ground injuries and fatalities

    CSIR Research Space (South Africa)

    Kelly, AM

    1996-10-01

    Full Text Available The quality of installation and grouting of rock reinforcing tendons is seen as a serious problem by the mining industry. Up to half of all full-column grouted steel tendons or rock bolts installed in South African gold and platinum mines...

  9. In situ solidification/stabilization pilot study for the treatment of coal tar contaminated soils and river sediments

    International Nuclear Information System (INIS)

    Lawson, M.A.; Venn, J.G.; Pugh, L.B.; Vallis, T.

    1996-01-01

    Coal tar contamination was encountered at a former coal gasification site in soils below the groundwater table, and in the sediments of the adjacent river. Ex situ remediation techniques at this site would be costly because of the need to dewater the impacted media. In situ solidification/stabilization was tested to evaluate its effectiveness. Treatability testing was performed to evaluate a Portland cement/fly ash binder system with added stabilizing agents. Results were sufficiently promising to warrant pilot testing. Grout containing Portland cement, fly ash, organically modified clay, and granular activated carbon was pilot tested at the site. Test specimens were collected and tested to evaluate durability, compressive strength, and permeability. The samples were extracted by several methods and analyzed to measure the leachable concentrations of organic compounds and metals. Results indicated acceptable physical characteristics. Leachable concentrations of most polynuclear aromatic compounds were decreased

  10. Grout to meet physical and chemical requirements for closure at Hanford grout vaults. Final report

    International Nuclear Information System (INIS)

    1994-01-01

    The US Army Engineer Waterways Experiment Station (WES) developed a grout based on portland cement, Class F fly ash, and bentonite clay, for the Hanford Grout Vault Program. The purpose of this grout was to fill the void between a wasteform containing 106-AN waste and the vault cover blocks. Following a successful grout development program, heat output, volume change, and compressive strength were monitored with time in simulated repository conditions and in full-depth physical models. This research indicated that the cold-cap grout could achieve and maintain adequate volume stability and other required physical properties in the internal environment of a sealed vault. To determine if contact with 106-AN liquid waste would cause chemical deterioration of the cold-cap grout, cured specimens were immersed in simulated waste. Over a period of 21 days at 150 F, specimens increased in mass without significant changes in volume. X-ray diffraction of reacted specimens revealed crystallization of sodium aluminum silicate hydrate. Scanning electron microscopy used with X-ray fluorescence showed that clusters if this phase had formed in grout pores, increasing grout density and decreasing its effective porosity. Physical and chemical tests collectively indicate a sealing component. However, the Hanford Grout Vault Program was cancelled before completion of this research. This report summarizes close-out Waterways Experiment Station when the Program was cancelled

  11. Tank closure reducing grout

    International Nuclear Information System (INIS)

    Caldwell, T.B.

    1997-01-01

    A reducing grout has been developed for closing high level waste tanks at the Savannah River Site in Aiken, South Carolina. The grout has a low redox potential, which minimizes the mobility of Sr 90 , the radionuclide with the highest dose potential after closure. The grout also has a high pH which reduces the solubility of the plutonium isotopes. The grout has a high compressive strength and low permeability, which enhances its ability to limit the migration of contaminants after closure. The grout was designed and tested by Construction Technology Laboratories, Inc. Placement methods were developed by the Savannah River Site personnel

  12. Grouting of nuclear waste vault shafts

    International Nuclear Information System (INIS)

    Gyenge, M.

    1980-01-01

    A nuclear waste vault must be designed and built to ensure adequate isolation of the nuclear wastes from human contact. Consequently, after a vault has been fully loaded it must be adequately sealed off to prevent radionuclide migration which may be provided by circulating ground water. Of particular concern in vault sealing are the physical and chemical properties of the sealing materials its long-term durability and stability and the techniques used for its emplacement. Present grouting technology and grout material are reviewed in terms of the particular needs of shaft grouting. Areas requiring research and development are indicated

  13. Laboratory testing of cement grouting of fractures in welded tuff

    International Nuclear Information System (INIS)

    Sharpe, C.J.; Daemen, J.J.

    1991-03-01

    Fractures in the rock mass surrounding a repository and its shafts, access drifts, emplacement rooms and holes, and exploratory or in-situ testing holes, may provide preferential flowpaths for the flow of groundwater or air, potentially containing radionuclides. Such cracks may have to be sealed. The likelihood that extensive or at least local grouting will be required as part of repository sealing has been noted in numerous publications addressing high level waste repository closing. The objective of this work is to determine the effectiveness of fracture sealing (grouting) in welded tuff. Experimental work includes measurement of intact and fracture permeability under various normal stresses and injection pressures. Grout is injected into the fractures. The effectiveness of grouting is evaluated in terms of grout penetration and permeability reduction, compared prior to and after grouting. Analysis of the results include the effect of normal stress, injection pressure, fracture roughness, grout rheology, grout bonding, and the radial extent of grout penetration. Laboratory experiments have been performed on seventeen tuff cylinders with three types of fractures: (1) tension induced cracks, (2) natural fractures, and (3) sawcuts. Prior to grouting, the hydraulic conductivity of the intact rock and of the fractures is measured under a range of normal stresses. The surface topography of the fracture is mapped, and the results are used to determine aperture distributions across the fractures. 72 refs., 76 figs., 25 tabs

  14. Acid Pit Stabilization Project (Volume 1 - Cold Testing) and (Volume 2 - Hot Testing)

    International Nuclear Information System (INIS)

    Loomis, G. G.; Zdinak, A. P.; Ewanic, M. A.; Jessmore, J. J.

    1998-01-01

    During the summer and fall of Fiscal Year 1997, a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Treatability Study was performed at the Idaho National Engineering and Environmental Laboratory. The study involved subsurface stabilization of a mixed waste contaminated soil site called the Acid Pit. This study represents the culmination of a successful technology development effort that spanned Fiscal Years 1994-1996. Research and development of the in situ grout stabilization technique was conducted. Hardware and implementation techniques are currently documented in a patent pending with the United States Patent and Trademark Office. The stabilization technique involved using jet grouting of an innovative grouting material to form a monolith out of the contamination zone. The monolith simultaneously provides a barrier to further contaminant migration and closes voids in the soil structure against further subsidence. This is accomplished by chemical incorporation of contaminants into less soluble species and achieving a general reduction in hydraulic conductivity within the monolith. The grout used for this study was TECT-HG, a relatively dense iron oxide-based cementitious grout. The treatability study involved cold testing followed by in situ stabilization of the Acid Pit. Volume 1 of this report discusses cold testing, performed as part of a ''Management Readiness Assessment'' in preparation for going hot. Volume 2 discusses the results of the hot Acid Pit Stabilization phase of this project. Drilling equipment was specifically rigged to reduce the spread of contamination, and all grouting was performed under a concrete block containing void space to absorb any grout returns. Data evaluation included examination of implementability of the grouting process and an evaluation of the contaminant spread during grouting. Following curing of the stabilized pit, cores were obtained and evaluated for toxicity characteristic leach ing

  15. Grouting of uranium mill tailings piles

    International Nuclear Information System (INIS)

    Boegly, W.J. Jr.; Tamura, T.; Williams, J.D.

    1984-03-01

    A program of remedial action was initiated for a number of inactive uranium mill tailings piles. These piles result from mining and processing of uranium ores to meet the nation's defense and nuclear power needs and represent a potential hazard to health and the environment. Possible remedial actions include the application of covers to reduce radon emissions and airborne transport of the tailings, liners to prevent groundwater contamination by leachates from the piles, physical or chemical stabilization of the tailings, or moving the piles to remote locations. Conventional installation of liners would require excavation of the piles to emplace the liner; however, utilization of grouting techniques, such as those used in civil engineering to stabilize soils, might be a potential method of producing a liner without excavation. Laboratory studies on groutability of uranium mill tailings were conducted using samples from three abandoned piles and employing a number of particulate and chemical grouts. These studies indicate that it is possible to alter the permeability of the tailings from ambient values of 10 -3 cm/s to values approaching 10 -7 cm/s using silicate grouts and to 10 -8 cm/s using acrylamide and acrylate grouts. An evaluation of grouting techniques, equipment required, and costs associated with grouting were also conducted and are presented. 10 references, 1 table

  16. Analysis of core samples from jet grouted soil

    International Nuclear Information System (INIS)

    Allan, M.L.; Kukacka, L.E.

    1995-10-01

    Superplasticized cementitious grouts were tested for constructing subsurface containment barriers using jet grouting in July, 1994. The grouts were developed in the Department of Applied Science at Brookhaven National Laboratory. The test site was located close to the Chemical Waste Landfill at Sandia National Laboratories, Albuquerque, NM. Sandia was responsible for the placement contract. The jet grouted soil was exposed to the service environment for one year and core samples were extracted to evaluate selected properties. The cores were tested for strength, density, permeability (hydraulic conductivity) and cementitious content. The tests provided an opportunity to determine the performance of the grouts and grout-treated soil. Several recommendations arise from the results of the core tests. These are: (1) grout of the same mix proportions as the final grout should be used as a drilling fluid in order to preserve the original mix design and utilize the benefits of superplasticizers; (2) a high shear mixer should be used for preparation of the grout; (3) the permeability under unsaturated conditions requires consideration when subsurface barriers are used in the vadose zone; and (4) suitable methods for characterizing the permeability of barriers in-situ should be applied

  17. Numerical Simulation and Optimization of Hole Spacing for Cement Grouting in Rocks

    Directory of Open Access Journals (Sweden)

    Ping Fu

    2013-01-01

    Full Text Available The fine fissures of V-diabase were the main stratigraphic that affected the effectiveness of foundation grout curtain in Dagang Mountain Hydropower Station. Thus, specialized in situ grouting tests were conducted to determine reasonable hole spacing and other parameters. Considering time variation of the rheological parameters of grout, variation of grouting pressure gradient, and evolution law of the fracture opening, numerical simulations were performed on the diffusion process of cement grouting in the fissures of the rock mass. The distribution of permeability after grouting was obtained on the basis of analysis results, and the grouting hole spacing was discussed based on the reliability analysis. A probability of optimization along with a finer optimization precision as 0.1 m could be adopted when compared with the accuracy of 0.5 m that is commonly used. The results could provide a useful reference for choosing reasonable grouting hole spacing in similar projects.

  18. REACTOR GROUT THERMAL PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

    2011-01-28

    Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

  19. Strength of High Performance Grouts

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes tests carried out on 5 experimental grouts developed by BASF Construction Materials and designed for use in grouted connections of offshore windmill foundations.......The present report describes tests carried out on 5 experimental grouts developed by BASF Construction Materials and designed for use in grouted connections of offshore windmill foundations....

  20. Remediation of SRS Basins by In Situ Stabilization/Solidification

    International Nuclear Information System (INIS)

    Ganguly, A.

    1999-01-01

    In the late summer of 1998, the Savannah River Site began remediation of two radiologically contaminated basins using in situ stabilization. These two high-risk, unlined basins contain radiological contaminants, which potentially pose significant risks to human health and the environment. The selected remedy involves in situ stabilization/solidification of the contaminated wastes (basin and pipeline soils, pipelines, vegetation, and other debris) followed by installation of a low permeability soil cover

  1. Fractal Prediction of Grouting Volume for Treating Karst Caverns along a Shield Tunneling Alignment

    Directory of Open Access Journals (Sweden)

    Wen-Chieh Cheng

    2017-06-01

    Full Text Available Karst geology is common in China, and buried karst formations are widely distributed in Guangdong province. In the process of shield tunneling, the abundant water resources present in karst caverns could lead to the potential for high water ingress, and a subsequent in situ stress change-induced stratum collapse. The development and distribution of karst caverns should therefore be identified and investigated prior to shield tunnel construction. Grouting is an efficient measure to stabilize karst caverns. The total volume of karst caverns along the shield tunneling alignment, and its relationship with the required volume of grouts, should be evaluated in the preliminary design phase. Conventionally, the total volume of karst caverns is empirically estimated based on limited geological drilling hole data; however, accurate results are rarely obtained. This study investigates the hydrogeology and engineering geology of Guangzhou, the capital of Guangdong province, and determines the fractal characteristics of the karst caverns along the tunnel section of Guangzhou metro line no. 9. The karst grouting coefficients (VR were found to vary from 0.11 in the case of inadequate drilling holes to 1.1 in the case where adequate drilling holes are provided. A grouting design guideline was furthermore developed in this study for future projects in karst areas.

  2. The use of alkali-activated fly ash grouts for the remediation of AMD from underground mines

    International Nuclear Information System (INIS)

    Eaker, C.A.; Longley, R.D.; Michaud, L.H.; Silsbee, M.R.

    1996-01-01

    In preparation for a field demonstration, laboratory studies were conducted using several fly ash grout formulations to determine the optimum grout for an underground mine environment. This paper discusses the portion of the overall project designed to examine grout-acid mine drainage (AMD) interactions including neutralization, leaching and armoring of the grouts. Leaching tests were performed to study the effects of fly ash grout on AMD, including the effects of armoring. The goal of this project is to study the feasibility of in-situ acid mine drainage treatment by injecting alkali-activated fly ash grout into an underground mine

  3. Silicate grout curtains behaviour for the protection of coastal aquifers

    International Nuclear Information System (INIS)

    Elektorowicz, M.; Chifrina, R.; Hesnawi, R.

    1997-01-01

    Tests were performed to evaluate the behaviour of silicate grout with different reagents (ethylacetate - formamide SA and calcium chloride SC) in pure silica sand and natural soils from coastal areas containing organic matter, clayey soil and silica sand. The grouted specimens were tested with simulated fresh and salt water. The setting process during chemical grouting in the soil and sand was studied. The grouting of soil and sand with SA caused a transfer to the environment of some compounds: sodium formate, sodium acetate, ammonia and part of the initial ethylacetate and formamide. This process had a tendency to decrease for approximately 4 months. The stability of specimens was low. The grouting of soil and sand with SC caused no significant contamination of the environment. The increase of pH of environmental water was even less than with SA grouting. Also, the stability of specimens is higher in comparison with SA grouting. Salt water protected the specimens grouted with SA and SC from destruction and prevented contamination

  4. A new and superior ultrafine cementitious grout

    International Nuclear Information System (INIS)

    Ahrens, E.H.

    1997-01-01

    Sealing fractures in nuclear waste repositories concerns all programs investigating deep burial as a means of disposal. Because the most likely mechanism for contaminant migration is by dissolution and movement through groundwater, sealing programs are seeking low-viscosity sealants that are chemically, mineralogically, and physically compatible with the host rock. This paper presents the results of collaborative work directed by Sandia National Laboratories (SNL) and supported by Whiteshell Laboratories, operated by Atomic Energy of Canada, Ltd. The work was undertaken in support of the Waste Isolation Pilot Plant (WIPP), an underground nuclear waste repository located in a salt formation east of Carlsbad, NM. This effort addresses the technology associated with long-term isolation of nuclear waste in a natural salt medium. The work presented is part of the WIPP plugging and sealing program, specifically the development and optimization of an ultrafine cementitious grout that can be injected to lower excessive, strain-induced hydraulic conductivity in the fractured rock termed the Disturbed Rock Zone (DRZ) surrounding underground excavations. Innovative equipment and procedures employed in the laboratory produced a usable cement-based grout; 90% of the particles were smaller than 8 microns and the average particle size was 4 microns. The process involved simultaneous wet pulverization and mixing. The grout was used for a successful in situ test underground at the WIPP. Injection of grout sealed microfractures as small as 6 microns (and in one rare instance, 3 microns) and lowered the gas transmissivity of the DRZ by up to three orders of magnitude. Following the WIPP test, additional work produced an improved version of the grout containing particles 90% smaller than 5 microns and averaging 2 microns. This grout will be produced in dry form, ready for the mixer

  5. GROUT-CONCRETE INTERFACE BOND PERFORMANCE: EFFECT OF INTERFACE MOISTURE ON THE TENSILE BOND STRENGTH AND GROUT MICROSTRUCTURE.

    Science.gov (United States)

    De la Varga, I; Muñoz, J F; Bentz, D P; Spragg, R P; Stutzman, P E; Graybeal, B A

    2018-05-01

    Bond between two cementitious materials is crucial in applications such as repairs, overlays, and connections of prefabricated bridge elements (PBEs), to name just a few. It is the latter that has special interest to the authors of this paper. After performing a dimensional stability study on grout-like materials commonly used as connections between PBEs, it was observed that the so-called 'non-shrink' cementitious grouts showed a considerable amount of early-age shrinkage. This might have negative effects on the integrity of the structure, due not only to the grout material's early degradation, but also to a possible loss of bond between the grout and the prefabricated concrete element. Many factors affect the bond strength between two cementitious materials (e.g., grout-concrete), the presence of moisture at the existing concrete substrate surface being one of them. In this regard, pre-moistening the concrete substrate surface prior to the application of the grout material is sometimes recommended for bond enhancement. This topic has been the focus of numerous research studies in the past; however, there is still controversy among practitioners on the real benefits that this practice might provide. This paper evaluates the tensile bond performance of two non-shrink cementitious grouts applied to the exposed aggregate surface of a concrete substrate, and how the supply of moisture at the grout-concrete interface affects the bond strength. "Pull-off" bond results show increased tensile bond strength when the concrete surface is pre-moistened. Reasons to explain the observed increased bond strength are given after a careful microstructural analysis of the grout-concrete interface. Interfaces where sufficient moisture is provided to the concrete substrate such that moisture movement from the grout is prevented show reduced porosity and increased hydration on the grout side of the interface, which is thought to directly contribute to the increased tensile bond

  6. Lab scale testing of novel natural analog in situ stabilization agents

    International Nuclear Information System (INIS)

    Shaw, P.

    1997-01-01

    This report summarizes the laboratory-scale test results on several novel in situ treatment and stabilization agents for buried hazardous and radioactive waste. Paraffin, hematite and phosphate materials were examined when combined with soil and other wastes representative of what might be present at buried waste DOE sites. Hematite was made from the reaction of agricultural iron and lime slurries to form gypsum and iron oxide/hydroxide. Common household paraffin was melted, both with and without a zeolitic additive, waste added and then cooled. Magnesium phosphate was made from the reaction of magnesium oxide and phosphoric acid or potassium biphosphate to form, magnesium phosphate. All were tested with soil and some with additional waste sumulants such as ash, machine oil and nitrate salts. The following laboratory-generated data indicate that all waste encapsulation materials tested are appropriate materials, for field in situ testing. Compressive strengths of treated Idaho National Engineering and Environment Laboratory (INEEL) soil and the waste encapsulation material were sufficient to prevent collapse of the void space in waste, i.e., greater than the NRC 60 psi minimum. The mineralogy and microstructure of hematite was amorphous but should progress to an interlocking crystalline solid. Phosphate was crystalline with characteristics of higher temperature ceramics. Paraffin is non crystalline but encapsulates even very fine grained INEEL soils. Each agent appears to be chemically and physically inert to possible waste materials such as, nitrates and machine cutting oil. Two of the agents hematite and phosphate react favorably with ash increasing the metals retention at higher waste loadings than Portland cement. Hematite, phosphate and zeolite decrease leaching of most hazardous metals from waste when compared to untreated waste and soil. Solution pH, time for reaction initiation, and viscosity values are conducive to jet-grouting application

  7. Grout Facilities standby plan

    Energy Technology Data Exchange (ETDEWEB)

    Claghorn, R.D.; Kison, P.F.; Nunamaker, D.R.; Yoakum, A.K.

    1994-09-29

    This plan defines how the Grout Facilities will be deactivated to meet the intent of the recently renegotiated Tri-Party Agreement (TPA). The TPA calls for the use of the grout process as an emergency option only in the event that tank space is not available to resolve tank safety issues. The availability of new tanks is expected by 1997. Since a grout startup effort would take an estimated two years, a complete termination of the Grout Disposal Program is expected in December 1995. The former Tank Waste Remediation (TWRS) Strategy, adopted in 1988, called for the contents of Hanford`s 28 newer double-shell waste tanks to be separated into high-level radioactive material to be vitrified and disposed of in a geologic repository; low-level wastes were to be sent to the Grout Facility to be made into a cement-like-mixture and poured into underground vaults at Hanford for disposal. The waste in the 149 older single-shell tanks (SST) were to undergo further study and analysis before a disposal decision was made.

  8. Grout Facilities standby plan

    International Nuclear Information System (INIS)

    Claghorn, R.D.; Kison, P.F.; Nunamaker, D.R.; Yoakum, A.K.

    1994-01-01

    This plan defines how the Grout Facilities will be deactivated to meet the intent of the recently renegotiated Tri-Party Agreement (TPA). The TPA calls for the use of the grout process as an emergency option only in the event that tank space is not available to resolve tank safety issues. The availability of new tanks is expected by 1997. Since a grout startup effort would take an estimated two years, a complete termination of the Grout Disposal Program is expected in December 1995. The former Tank Waste Remediation (TWRS) Strategy, adopted in 1988, called for the contents of Hanford's 28 newer double-shell waste tanks to be separated into high-level radioactive material to be vitrified and disposed of in a geologic repository; low-level wastes were to be sent to the Grout Facility to be made into a cement-like-mixture and poured into underground vaults at Hanford for disposal. The waste in the 149 older single-shell tanks (SST) were to undergo further study and analysis before a disposal decision was made

  9. Grouting Applications in Cindere Dam

    Directory of Open Access Journals (Sweden)

    Devrim ALKAYA

    2011-01-01

    Full Text Available Grouting is one of the most popular method to control the water leakage in fill dam constructions. With this regard this method is widely used in all the world. Geological and geotechnical properties of rock are important parameters affect the design of grouting. In this study, geotechnical properties of Cindere Dam's base rock and the grouting prosedure have been investigated with grouting pressure.

  10. In situ uranium stabilization by microbial metabolites

    International Nuclear Information System (INIS)

    Turick, Charles E.; Knox, Anna S.; Leverette, Chad L.; Kritzas, Yianne G.

    2008-01-01

    Microbial melanin production by autochthonous bacteria was explored in this study as a means to increase U immobilization in U contaminated soil. This article demonstrates the application of bacterial physiology and soil ecology for enhanced U immobilization in order to develop an in situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE), Savannah River Site (SRS), South Carolina, as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >10 6 cells per g wet soil. Pyomelanin demonstrated U complexing and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in a field test demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments

  11. IN SITU URANIUM STABILIZATION BY MICROBIAL METABOLITES

    Energy Technology Data Exchange (ETDEWEB)

    Turick, C; Anna Knox, A; Chad L Leverette,C; Yianne Kritzas, Y

    2006-11-29

    Soil contaminated with U was the focus of this study in order to develop in-situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE) Savannah River Site (SRS) as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >106 cells/g wet soil. Pyomelanin demonstrated U chelating and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in field tests demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments.

  12. Silica sol as grouting material: a physio-chemical analysis.

    Science.gov (United States)

    Sögaard, Christian; Funehag, Johan; Abbas, Zareen

    2018-01-01

    At present there is a pressing need to find an environmentally friendly grouting material for the construction of tunnels. Silica nanoparticles hold great potential of replacing the organic molecule based grouting materials currently used for this purpose. Chemically, silica nanoparticles are similar to natural silicates which are essential components of rocks and soil. Moreover, suspensions of silica nanoparticles of different sizes and desired reactivity are commercially available. However, the use of silica nanoparticles as grouting material is at an early stage of its technological development. There are some critical parameters such as long term stability and functionality of grouted silica that need to be investigated in detail before silica nanoparticles can be considered as a reliable grouting material. In this review article we present the state of the art regarding the chemical properties of silica nanoparticles commercially available, as well as experience gained from the use of silica as grouting material. We give a detailed description of the mechanisms underlying the gelling of silica by different salt solutions such as NaCl and KCl and how factors such as particle size, pH, and temperature affect the gelling and gel strength development. Our focus in this review is on linking the chemical properties of silica nanoparticles to the mechanical properties to better understand their functionality and stability as grouting material. Along the way we point out areas which need further research.

  13. Relationship Between Flowability And Tank Closure Grout Quality

    International Nuclear Information System (INIS)

    Langton, C. A.; Stefanko, D. B.; Hay, M. S.

    2012-01-01

    After completion of waste removal and chemical cleaning operations, Tanks 5-F and 6-F await final closure. The project will proceed with completing operational closure by stabilizing the tanks with grout. Savannah River Remediation's (SRR) experience with grouting Tanks 18-F and 19-F showed that slump-flow values were correlated with flow/spread inside these tanks. Less mounding was observed when using grouts with higher slump-flow. Therefore, SRNL was requested to evaluate the relationship between flowability and cured properties to determine whether the slump-flow maximum spread of Mix LP no. 8-16 could be increased from 28 inches to 30 inches without impacting the grout quality. A request was also made to evaluate increasing the drop height from 5 feet to 10 feet with the objective of enhancing the flow inside the tank by imparting more kinetic energy to the placement. Based on a review of the grout property data for Mix LP no. 8-16 collected from Tank 18-F and 19-F quality control samples, the upper limit for slump-flow measured per ASTM C 1611 can be increased from 28 to 30 inches without affecting grout quality. However, testing should be performed prior to increasing the drop height from 5 to 10 feet or observations should be made during initial filling operations to determine whether segregation occurs as a function of drop heights between 5 and 10 feet. Segregation will negatively impact grout quality. Additionally, increasing the delivery rate of grout into Tanks 5-F and 6-F by using a higher capacity concrete/grout pump will result in better grout spread/flow inside the tanks

  14. Calorimetric examination of hydrofracture grouts

    International Nuclear Information System (INIS)

    Stinton, D.P.; Berger, R.L.

    1985-01-01

    A hydrofracture grout sample obtained during the SI-10 injection campaign was studied by calorimetry. The calorimetry curve of this grout was compared with laboratory-produced grout containing simulated wastes. Initiation of the cement-water reaction for the actual grout was delayed several days by the presence of a large quantity of boron in the waste. Although the hydration of cement was delayed, eventually the cement reacted with water and the grout hardened. This test indicates the potential need to analyze sludges for compounds known to retard cement hydration. 10 references, 5 figures, 4 tables

  15. Rheological Characteristics of Cement Grout and its Effect on Mechanical Properties of a Rock Fracture

    Science.gov (United States)

    Liu, Quansheng; Lei, Guangfeng; Peng, Xingxin; Lu, Chaobo; Wei, Lai

    2018-02-01

    Grouting reinforcement, which has an obvious strengthening effect on fractured rock mass, has been widely used in various fields in geotechnical engineering. The rheological properties of grout will greatly affect its diffusion radius in rock fractures, and the water-cement ratio is an important factor in determining the grouting flow patterns. The relationship between shear stress and shear rate which could reflect the grout rheological properties, the effects of water-cement ratio, and temperature on the rheological properties of grouting was studied in the laboratory. Besides, a new method for producing fractured rock specimens was proposed and solved the problem of producing natural fractured rock specimens. To investigate the influences of grouting on mechanical properties of a rock fracture, the fractured rock specimens made using the new method were reinforced by grouting on the independent designed grouting platform, and then normal and tangential mechanical tests were carried out on fractured rock specimens. The results showed that the mechanical properties of fractured rock mass are significantly improved by grouting, the peak shear strength and residual strength of rock fractures are greatly improved, and the resistance to deformation is enhanced after grouting. Normal forces affect the tangential behavior of the rock fracture, and the tangential stress strength increases with normal forces. The strength and stability of fractured rock mass are increased by grouting reinforcement.

  16. Field test of ethanol/bentonite slurry grouting into rock fracture

    International Nuclear Information System (INIS)

    Motoyuki Asada; Hitoshi Nakashima; Takashi Ishii; Sumio Horiuchi

    2006-01-01

    Crystalline rocks have fractures which may cause unexpected routes of groundwater seepage. Cement grouting is one of the most effective methods to minimize seepage; however, cement materials may not be suitable for the purpose of extra-long durability, because cement is neutralized or degraded by chemical and physical influence of chemical reaction. Natural clay like bentonite is one of the most promising materials for seepage barrier; however, water/bentonite grout is so viscous that enough amount of bentonite can not be grouted into rock fractures. To increase bentonite content in grout with low viscosity, the utilization of ethanol as a mixing liquid was studied. Ethanol suppresses bentonite swelling, and more bentonite can be injected more than that of water/bentonite slurry. In this paper, grouting into in-situ rock mass fracture from the ground surface was tested to investigate the barrier performance and workability of ethanol/bentonite slurry as a grouting material. (author)

  17. In situ vitrification: application analysis for stabilization of transuranic waste

    International Nuclear Information System (INIS)

    Oma, K.H.; Farnsworth, R.K.; Rusin, J.M.

    1982-09-01

    The in situ vitrification process builds upon the electric melter technology previously developed for high-level waste immobilization. In situ vitrification converts buried wastes and contaminated soil to an extremely durable glass and crystalline waste form by melting the materials, in place, using joule heating. Once the waste materials have been solidified, the high integrity waste form should not cause future ground subsidence. Environmental transport of the waste due to water or wind erosion, and plant or animal intrusion, is minimized. Environmental studies are currently being conducted to determine whether additional stabilization is required for certain in-ground transuranic waste sites. An applications analysis has been performed to identify several in situ vitrification process limitations which may exist at transuranic waste sites. Based on the process limit analysis, in situ vitrification is well suited for solidification of most in-ground transuranic wastes. The process is best suited for liquid disposal sites. A site-specific performance analysis, based on safety, health, environmental, and economic assessments, will be required to determine for which sites in situ vitrification is an acceptable disposal technique. Process economics of in situ vitrification compare favorably with other in-situ solidification processes and are an order of magnitude less than the costs for exhumation and disposal in a repository. Leachability of the vitrified product compares closely with that of Pyrex glass and is significantly better than granite, marble, or bottle glass. Total release to the environment from a vitrified waste site is estimated to be less than 10 -5 parts per year. 32 figures, 30 tables

  18. Cement-based grouts in geological disposal of radioactive waste

    International Nuclear Information System (INIS)

    Onofrei, M.

    1996-01-01

    The behavior and performance of a specially developed high-performance cement-based grout has been studied through a combined laboratory and in situ research program conducted under the auspices of the Canadian Nuclear Fuel Waste Management Program (CNFWMP). A new class of cement-based grouts - high-performance grouts-with the ability to penetrate and seal fine fractures was developed and investigated. These high-performance grouts, which were injected into fractures in the granitic rock at the Underground Research Laboratory (URL) in Canada, are shown to successfully reduce the hydraulic conductivity of the rock mass from -7 m s -1 to 10 -9 m s -1 and to penetrate fissures in the rock with apertures as small as 10 μm. Furthermore, the laboratory studies have shown that this high - performance grout has very low hydraulic conductivity and is highly leach resistant under repository conditions. Microcracks generated in this materials from shrinkage, overstressing or thermal loads are likely to self-seal. The results of these studies suggest that the high-performance grouts can be considered as viable materials in disposal-vault sealing applications. Further work is needed to fully justify extrapolation of the results of the laboratory studies to time scales relevant to performance assessment

  19. Grout for closure of the demonstration vault at the US DOE Hanford Facility. Final report

    International Nuclear Information System (INIS)

    Wakeley, L.D.; Ernzen, J.J.

    1992-08-01

    The Waterways Experiment Station (WES) developed a grout to be used as a cold- (nonradioactive) cap or void-fill grout between the solidified low-level waste and the cover blocks of a demonstration vault for disposal of phosphate-sulfate waste (PSW) at the US Department of Energy (DOE) Hanford Facility. The project consisted of formulation and evaluation of candidate grouts and selection of the best candidate grout, followed by a physical scale-model test to verify grout performance under project-specific conditions. Further, the project provided data to verify numerical models (accomplished elsewhere) of stresses and isotherms inside the Hanford demonstration vault. Evaluation of unhardened grout included obtaining data on segregation, bleeding, flow, and working time. For hardened grout, strength, volume stability, temperature rise, and chemical compatibility with surrogate wasteform grout were examined. The grout was formulated to accommodate unique environmental boundary conditions (vault temperature = 45 C) and exacting regulatory requirements (mandating less than 0.1% shrinkage with no expansion and no bleeding); and to remain pumpable for a minimum of 2 hr. A grout consisting of API Class H oil-well cement, an ASTM C 618 Class F fly ash, sodium bentonite clay, and a natural sand from the Hanford area met performance requirements in laboratory studies. It is recommended for use in the DOE Hanford demonstration PSW vault

  20. Cross-check of ex-situ and in-situ metrology of a bendable temperature stabilized KB mirror

    International Nuclear Information System (INIS)

    Yuan Sheng; Goldberg, Kenneth A.; Yashchuk, Valeriy V.; Celestre, Richard; McKinney, Wayne R.; Morrison, Gregory; Macdougall, James; Mochi, Iacopo; Warwick, Tony

    2011-01-01

    At the Advanced Light Source (ALS), we are developing broadly applicable, high-accuracy, in-situ, at-wavelength wavefront slope measurement techniques for Kirkpatrick-Baez (KB) mirror nano-focusing. In this paper, we report an initial cross-check of ex-situ and in-situ metrology of a bendable temperature stabilized KB mirror. This cross-check provides a validation of the in-situ shearing interferometry, currently under development at the ALS.

  1. Practical Model of Cement Based Grout Mix Design, for Use into Low Level Radiation Waste Management

    Directory of Open Access Journals (Sweden)

    Radu Lidia

    2015-12-01

    Full Text Available The cement based grouts, as functional performance composite materials, are widely used for both immobilisation and encapsulation as well as for stabilization in the field of inorganic waste management. Also, to ensure that low level radioactive waste (LLW are contained for storage and ultimate disposal, they are encapsulated or immobilized in monolithic waste forms, with cement –based grouts.

  2. Stabilization of contaminated soils by in situ vitrification

    International Nuclear Information System (INIS)

    Timmerman, C.L.

    1984-01-01

    In Situ Vitrification is an emerging technology developed by Pacific Northwest Laboratory for potential in-place immobilization of radioactive wastes. The contaminated soil is stabilized and converted to an inert glass form. This conversion is accomplished by inserting electrodes in the soil and establishing an electric current between the electrodes. The electrical energy causes a joule heating effect that melts the soil during processing. Any contaminants released from the melt are collected and routed to an off-gas treatment system. A stable and durable glass block is produced which chemically and physically encapsulates any residual waste components. In situ vitrification has been developed for the potential application to radioactive wastes, specifically, contaminated soil sites; however, it could possibly be applied to hazardous chemical and buried munitions waste sites. The technology has been developed and demonstrated to date through a series of 21 engineering-scale tests [producing 50 to 1000 kg (100 to 2000 lb) blocks] and seven pilot-scale tests [producing 9000 kg (20,000 lb) blocks], the most recent of which illustrated treatment of actual radioactively contaminated soil. Testing with some organic materials has shown relatively complete thermal destruction and incineration. Further experiments have documented the insensitivity of in situ vitrification to soil characteristics such as fusion temperature, specific heat, thermal conductivity, electrical resistivity, and moisture content. Soil inclusions such as metals, cements, ceramics, and combustibles normally present only minor process limitations. Costs for hazardous waste applications are estimated to be less than $175/m 3 ($5.00/ft 3 ) of material vitrified. For many applications, in situ vitrification can provide a cost-effective alternative to other disposal options. 13 references, 4 figures, 1 table

  3. Innovative technology summary report: Innovative grouting and retrieval

    International Nuclear Information System (INIS)

    1998-10-01

    Innovative grouting and retrieval (IGR) technology provides an innovative and cost-effective approach for full-pit and hot-spot retrieval of buried transuranic (TRU) waste sites and in situ disposal of buried waste with improved confinement. Innovative grouting technology: minimizes spreading of contamination by agglomerating the soil particles containing plutonium/americium particulates into nonaerosolizable particles; minimizes worker risks and exposure; is more effective in controlling the spread of contamination than common mining practices such as directed air flow, misting, and fixant sprays; eliminates further treatment because the grouted, rubberized waste is ready for shipment to the Waste Isolation Pilot Project (WIPP); reduces capital expenditures, operating costs, and containment structure requirements; and is an estimated five times faster than the baseline technology of removal, packaging, and storage

  4. Sealing properties of cement-based grout materials used in the rock sealing project

    International Nuclear Information System (INIS)

    Onofrei, M.; Gray, M.N.; Pusch, R.; Boergesson, L.; Karnland, O.; Shenton, B.; Walker, B.

    1993-12-01

    The Task Force on Sealing Materials and Techniques of the Stripa Project recommended that work be undertaken to study the sealing properties of cement-based grout materials. A new class of cement-based grouts (high-performance grouts) with the ability to penetrate and seal fine fractures in granite was investigated. The materials were selected for their small mean particle size and the ability to be made fluid by a superplasticizer at low water/cementitious-materials ratios. The fundamental physical and chemical properties (such as the particle size and chemical composition) of the materials were evaluated. The rheological properties of freshly mixed grouts, which control the workability of the grouts, were determined together with the properties of hardened materials, which largely control the long-term performance (longevity) of the materials in repository settings. The materials selected were shown to remain gel-like during the setting period, and so the grouts may be expected to remain largely homogenous during and after injection into the rock without separating into solid and liquid phases. The hydraulic conductivity and strength of hardened grouts were determined. The microstructure of the bulk grouts was characterized by a high degree of homogeneity with extremely fine porosity. The low hydraulic conductivity and good mechanical properties are consistent with the extremely fine porosity. The ability of the fractured grouts to self-seal was also observed in tests in which the hydraulic conductivity of recompacted granulated grouts was determined. The laboratory tests were carried out in parallel with investigations of the in situ performance of the materials and with the development of geochemical and theoretical models for cement-based grout longevity. (author). 56 refs., 15 tabs., 98 figs

  5. Sealing properties of cement-based grout materials. Final report on the Rock sealing project

    International Nuclear Information System (INIS)

    Onofrei, M.; Gray, Malcolm; Shenton, B.; Walker, Brad; Pusch, R.; Boergesson, L.; Karnland, O.

    1992-10-01

    This report presents the results of laboratory studies of material properties. A number of different high performance grouts were investigated. The laboratory studies focused on mixtures of sulphate resistant portland cement, silica fume, superplasticizer and water. The ability of the thin films to self seal was confirmed. The surface reactions were studied in specimens of hardened grouts. The leach rates were found to vary with grout and water composition and with temperature. The short-term hydraulic and strength or properties of the hardened grout were determined. These properties were determined for the grouts both in-bulk and as thin-films. The hydraulic conductivities of the bulk, hardened material were found to be less than 10 -14 m/s. The hydraulic conductivities of thin films were found to be less than 10 -11 m/s. Broken, the hydraulic conductivity of the thin films could be increased to 10 -7 m/s. Examination of the leached grout specimens revealed a trend for the pore sizes to decrease with time. The propensity for fractured grouts to self seal was also observed in tests in which the hydraulic conductivity of recompacted mechanically disrupted, granulated grouts was determined. These tests showed that the hydraulic conductivity decreased rapidly with time. The decreases were associated with decreases in mean pore size. In view of the very low hydraulic conductivity it is likely that surface leaching at the grout/groundwater interface will be that major process by which bulk high-performance grouts may degrade. With the completion of the laboratory, in situ and modelling studies it appears that high-performance cement based grouts can be considered as viable materials for some repository sealing applications. Some of the uncertainties that remain are identified in this report. (54 refs.)

  6. Sealing properties of cement-based grout materials used in the rock sealing project

    Energy Technology Data Exchange (ETDEWEB)

    Onofrei, M; Gray, M N; Pusch, R; Boergesson, L; Karnland, O; Shenton, B; Walker, B

    1993-12-01

    The Task Force on Sealing Materials and Techniques of the Stripa Project recommended that work be undertaken to study the sealing properties of cement-based grout materials. A new class of cement-based grouts (high-performance grouts) with the ability to penetrate and seal fine fractures in granite was investigated. The materials were selected for their small mean particle size and the ability to be made fluid by a superplasticizer at low water/cementitious-materials ratios. The fundamental physical and chemical properties (such as the particle size and chemical composition) of the materials were evaluated. The rheological properties of freshly mixed grouts, which control the workability of the grouts, were determined together with the properties of hardened materials, which largely control the long-term performance (longevity) of the materials in repository settings. The materials selected were shown to remain gel-like during the setting period, and so the grouts may be expected to remain largely homogenous during and after injection into the rock without separating into solid and liquid phases. The hydraulic conductivity and strength of hardened grouts were determined. The microstructure of the bulk grouts was characterized by a high degree of homogeneity with extremely fine porosity. The low hydraulic conductivity and good mechanical properties are consistent with the extremely fine porosity. The ability of the fractured grouts to self-seal was also observed in tests in which the hydraulic conductivity of recompacted granulated grouts was determined. The laboratory tests were carried out in parallel with investigations of the in situ performance of the materials and with the development of geochemical and theoretical models for cement-based grout longevity. (author). 56 refs., 15 tabs., 98 figs.

  7. Self Cleanable Tile Grout

    Directory of Open Access Journals (Sweden)

    Mehmet CANBAZ

    2016-03-01

    Full Text Available In this study, In this study, self-cleaning tile grout and white cement specimens are produced and the effect of self-cleaning mechanism of TiO2 is tested. Effects of TiO2 amount and TiO2 type are tested and compared. Anatase form and rutile TiO2 additive are used in the study. In addition, effects of silicate additives on the self-cleaning mechanism is determined. Studies are conducted with respect to Italian UNI code. This study presents a method for solving rust between the tiles of ceramic wet floor coverings with photocatalysis method and then removing the dirt with secondary effects such as water, wind etc.

  8. ORNL grouting technologies for immobilizing hazardous wastes

    International Nuclear Information System (INIS)

    Dole, L.R.; Trauger, D.B.

    1983-01-01

    The Cement and Concrete Applications Group at the Oak Ridge National Laboratory (ORNL) has developed versatile and inexpensive processes to solidify large quantities of hazardous liquids, sludges, and solids. By using standard off the shelf processing equipment, these batch or continuous processes are compatible with a wide range of disposal methods, such as above-ground storage, shallow-land burial, deep geological disposal, sea-bed dumping, and bulk in-situ solidification. Because of their economic advantages, these latter bulk in-situ disposal scenarios have received the most development. ORNL's experience has shown that tailored cement-based formulas can be developed which tolerate wide fluctuations in waste feed compositions and still maintain mixing properties that are compatible with standard equipment. In addition to cements, these grouts contain pozzolans, clays and other additives to control the flow properties, set-times, phase separations and impacts of waste stream fluctuation. The cements, fly ashes and other grout components are readily available in bulk quantities and the solids-blends typically cost less than $0.05 to 0.15 per waste gallon. Depending on the disposal scenario, total disposal costs (material, capital, and operating) can be as low as $0.10 to 0.50 per gallon

  9. Heat transfer analyses for grout disposal of radioactive double-shell slurry and customer wastes

    International Nuclear Information System (INIS)

    Robinson, S.M.; Gilliam, T.M.; McDaniel, E.W.

    1987-04-01

    Grout immobilization is being considered by Rockwell Hanford Operations (Rockwell Hanford) as a permanent disposal method for several radioactive waste streams. These include disposal of customer and double-shell slurry wastes in earthen trenches and in single-shell underground waste storage tanks. Heat transfer studies have previously been made to determine the maximum heat loading for grout disposal of various wastes under similar conditions, but a sensitivity analysis of temperature profiles to input parameters was needed. This document presents the results of heat transfer calculations for trenches containing grouted customer and double-shell slurry wastes and for in situ disposal of double-shell wastes in single-shell, domed concrete storage tanks. It discusses the conditions that lead to maximum grout temperatures of 250 0 F during the curing stage and 350 0 F thereafter and shows the dependence of these temperatures on input parameters such as soil and grout thermal conductivity, grout specific heat, waste loading, and disposal geometries. Transient heat transfer calculations were made using the HEATING6 computer code to predict temperature profiles in solidified low-level radioactive waste disposal scenarios at the Rockwell Hanford site. The calculations provide guidance for the development of safe, environmentally acceptable grout formulas for the Transportable Grout Facility. 11 refs

  10. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1992-07-01

    The Grout Treatment Facility (GTF) will provide permanent disposal for approximately 43 Mgal of radioactive liquid waste currently being stored in underground tanks on the Hanford Site. The first step in permanent disposal is accomplished by solidifying the low-level liquid waste with cementitious dry materials. The resulting grout is cast within underground vaults. This report on the GTF contains information on the following: Hanford Site Maps, road evaluation for the grout treatment facility, Department of Ecology certificate of non-designation for centralia fly ash, double-shell tank waste compositional modeling, laboratory analysis reports for double-shell tank waste, stored in tanks 241-AN-103, 241-AN-106, and 241-AW-101, grout vault heat transfer results for M-106 grout formulation, test results for extraction procedure toxicity testing, test results for toxicity testing of double-shell tank grout, pilot-scale grout production test with a simulated low-level waste, characterization of simulated low-level waste grout produced in a pilot-scale test, description of the procedure for sampling nonaging waste storage tanks, description of laboratory procedures, grout campaign waste composition verification, variability in properties of grouted phosphate/sulfate N-reactor waste, engineering drawings, description of operating procedures, equipment list--transportable grout equipment, grout treatment facility--tank integrity assessment plan, long-term effects of waste solutions on concrete and reinforcing steel, vendor information, grout disposal facilities construction quality assurance plan, and flexible membrane liner/waste compatibility test results

  11. Grout and Glass Performance Maximizing the Loading of ORNL Tank Sludges

    International Nuclear Information System (INIS)

    Burgess, M.W.; Mattus, A.J.; Spence, R.D.; Travis, J.R.

    1999-01-01

    Grouting and vitrification are currently two likely stabilization and solidification alternatives for radioactive and hazardous mixed wastes stored at Department of Energy (DOE) facilities. Grouting has been used to stabilize and solidify hazardous and low-level radioactive waste for decades. Vitrification has been developed as a high-level radioactive alternative for decades and has been under development recently as a mixed-waste alternative disposal technology

  12. Characterisation, design and execution of two grouting fans at 450 m level, Aespoe HRL

    Energy Technology Data Exchange (ETDEWEB)

    Emmelin, Ann [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Eriksson, Magnus [Royal Inst. of Technology, Stockholm (Sweden); Fransson, Aasa [Chalmers Univ. of Technology, Goeteborg (Sweden)

    2004-09-01

    During June 2003 a grouting field experiment was carried out at Aespoe HRL, in connection with the construction of a tunnel (TASQ) for the Aespoe Pillar Stability Experiment (APSE). The tunnel is situated in connection to the elevator shaft landing at 450 m depth and runs in direction N/E. The grouting was carried out as part of the ordinary construction work, but was accompanied by extra investigations and analyses during operations and an active adaptation of a basic grouting design to the encountered conditions. The main objectives of this set-up were to Investigate what can be achieved with best available technology, material and knowledge under the current conditions, i.e. a relatively tight crystalline rock mass at great depth; Collect data and evaluate theories resulting from previous research projects on characterisation and predictions on grout spread; Collect data to further develop those above mentioned theories; Contribute to the achievement of good conditions at the experimental site for the pillar stability experiments. The characterization method is based on analyses of stepwise investigations consisting of investigations in an initially drilled core-drill hole followed by probe and grouting boreholes with pressure-build-up tests and measuring of inflow during drilling, all aiming at identifying the singular fractures that are to be sealed. The decision about grouting design is based on the successively up-dated rock description from the characterization and iterative selection and testing of grouting design and grout in a numeric model, resulting in an expected grout spread and sealing effect. Based on investigations and analysis of results from investigations of a core-drilled hole at the site, a basic design was set up, together with conditions for application. Probe boreholes covering the first anticipated fan gave substantially larger inflows than expected, and subsequently the design was changed. A first round was drilled and grouted, sealing

  13. Characterisation, design and execution of two grouting fans at 450 m level, Aespoe HRL

    International Nuclear Information System (INIS)

    Emmelin, Ann; Eriksson, Magnus; Fransson, Aasa

    2004-09-01

    During June 2003 a grouting field experiment was carried out at Aespoe HRL, in connection with the construction of a tunnel (TASQ) for the Aespoe Pillar Stability Experiment (APSE). The tunnel is situated in connection to the elevator shaft landing at 450 m depth and runs in direction N/E. The grouting was carried out as part of the ordinary construction work, but was accompanied by extra investigations and analyses during operations and an active adaptation of a basic grouting design to the encountered conditions. The main objectives of this set-up were to Investigate what can be achieved with best available technology, material and knowledge under the current conditions, i.e. a relatively tight crystalline rock mass at great depth; Collect data and evaluate theories resulting from previous research projects on characterisation and predictions on grout spread; Collect data to further develop those above mentioned theories; Contribute to the achievement of good conditions at the experimental site for the pillar stability experiments. The characterization method is based on analyses of stepwise investigations consisting of investigations in an initially drilled core-drill hole followed by probe and grouting boreholes with pressure-build-up tests and measuring of inflow during drilling, all aiming at identifying the singular fractures that are to be sealed. The decision about grouting design is based on the successively up-dated rock description from the characterization and iterative selection and testing of grouting design and grout in a numeric model, resulting in an expected grout spread and sealing effect. Based on investigations and analysis of results from investigations of a core-drilled hole at the site, a basic design was set up, together with conditions for application. Probe boreholes covering the first anticipated fan gave substantially larger inflows than expected, and subsequently the design was changed. A first round was drilled and grouted, sealing

  14. In-situ thermoelectric stabilization of radioactive wastes

    International Nuclear Information System (INIS)

    Brouns, R.A.; Timmerman, C.L.

    1982-02-01

    A new process for stabilizing buried radioactive wastes without exhumation is being developed by Pacific Northwest Laboratory (PNL). The process, known as in situ vitrification, converts waste and contaminated soil to a durable glass and crystalline material by passing an electric current between electrodes placed in the ground. Joule heating created by the flowing current has generated temperatures over 1700 0 C which cause the soil to melt and dissolve or encapsulate the wastes. Engineering-scale tests conducted in the laboratory have melted approximately 45 kgs (30 liters) of soil at a time by this technique. Encouraging results from these engineering-scale tests led to the design and construction of a pilot-scale field test unit which has solidified approximately 9000 kg of simulated contaminated soil per test. Test results and evaluations to date have been very promising. No detectable migration of hazardous species into uncontaminated soil has been found, and volatilization during melting has been very low. Leach studies have found the vitrified soil to be a highly durable waste form similar to pyrex glass. Electrical power costs to solidify a disposal site have been calculated at less than $70 per cubic meter ($2/ft 3 ) of waste. Future activities include both radioactive and nonradioactive pilot and large-scale tests

  15. In-situ stabilization of radioactively contaminated low-level solid wastes buried in shallow trenches: an assessment

    International Nuclear Information System (INIS)

    Arora, H.S.; Tamura, T.; Boegly, W.J.

    1980-09-01

    The potential effectiveness of materials for in-situ encapsulation of low-level, radioactively contaminated solid waste buried in shallow trenches is enumerated. Cement, clay materials, and miscellaneous sorbents, aqueous and nonaqueous gelling fluids and their combinations are available to solidify contaminated free water in trenches, to fill open voids, and to minimize radionuclide mobility. The success of the grouting technique will depend on the availability of reliable geohydrologic data and laboratory development of a mix with enhanced sorption capacity for dominant radionuclides present in the trenches. A cement-bentonite-based grout mix with low consistency for pumping, several hours controlled rate of hardening, negligible bleeding, and more than 170 kPa (25 psi) compressive strength are a few of the suggested parameters in laboratory mix development. Cost estimates of a cement-bentonite-based grout mix indicate that effective and durable encapsulation can be accomplished at a reasonable cost (about $113 per cubic meter). However, extensive implementation of the method suggests the need for a field demonstration of the method. 53 references

  16. Sludge displacement verification for reducing grout report

    International Nuclear Information System (INIS)

    Caldwell, T.B.; Langton, C.A.

    1997-01-01

    To support the closure of HLW tanks at SRS, a reducing grout was developed that is formulated to reduce the mobility of radionuclides left in each tank. During non-radioactive flow tests of the grout, it was discovered that, in addition to its desired properties, the grout has the ability to move residual waste a considerable distance across the tank floor

  17. Method of producing grouting mortar

    Energy Technology Data Exchange (ETDEWEB)

    Shelomov, I K; Alchina, S I; Dizer, E I; Gruzdeva, G A; Nikitinskii, V I; Sabirzyanov, A K

    1980-10-07

    A method of producing grouting mortar by mixing the cement with an aqueous salt solution is proposed. So as to increase the quality of the mortar through an acceleration of the time for hardening, the mixture is prepared in two stages, in the first of which 20-30% of the entire cement batch hardens, and in the second of which the remainder of the cement hardens; 1-3-% of an aqueous salt solution is used in quantities of 0.5/1 wt.-% of weight of the cement. The use of this method of producing grouting mortar helps to increase the flexural strength of the cement brick up to 50% after two days ageing by comparison with the strength of cement brick produced from grouting mortar by ordinary methods utilizing identical quantities of the initial components (cement, water, chloride).

  18. Engineering feasibility analysis for in-situ stabilization of Canonsburg residues. [UMTRA project

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    The US Department of Energy is considering several methods for carrying out remedial actions in Canonsburg, Pennsylvania, at the site of an inactive uranium-processing mill. The main objective of this study is to determine the feasibility of in-situ stabilization as the remedial action. In-situ stabilization is an alternative to site decontamination and offsite disposal. The problems associated with offsite hauling of large quantities of contaminated material and with the location and development of a new disposal site could be avoided by the implementation of an in-situ stabilization concept. In addition, the in-situ approach would be more cost-effective than offsite disposal. This study will establish that a technically feasible and implementable in-situ stabilization concept can be developed that meets regulatory requirements and is cost effective. This study in no way commits the DOE to implement any specific actions described herein. 11 refs., 30 figs., 24 tabs.

  19. Engineering feasibility analysis for in-situ stabilization of Canonsburg residues

    International Nuclear Information System (INIS)

    1982-01-01

    The US Department of Energy is considering several methods for carrying out remedial actions in Canonsburg, Pennsylvania, at the site of an inactive uranium-processing mill. The main objective of this study is to determine the feasibility of in-situ stabilization as the remedial action. In-situ stabilization is an alternative to site decontamination and offsite disposal. The problems associated with offsite hauling of large quantities of contaminated material and with the location and development of a new disposal site could be avoided by the implementation of an in-situ stabilization concept. In addition, the in-situ approach would be more cost-effective than offsite disposal. This study will establish that a technically feasible and implementable in-situ stabilization concept can be developed that meets regulatory requirements and is cost effective. This study in no way commits the DOE to implement any specific actions described herein. 11 refs., 30 figs., 24 tabs

  20. Rock fracture grouting with microbially induced carbonate precipitation

    Science.gov (United States)

    Minto, James M.; MacLachlan, Erica; El Mountassir, Gráinne; Lunn, Rebecca J.

    2016-11-01

    Microbially induced carbonate precipitation has been proposed for soil stabilization, soil strengthening, and permeability reduction as an alternative to traditional cement and chemical grouts. In this paper, we evaluate the grouting of fine aperture rock fractures with calcium carbonate, precipitated through urea hydrolysis, by the bacteria Sporosarcina pasteurii. Calcium carbonate was precipitated within a small-scale and a near field-scale (3.1 m2) artificial fracture consisting of a rough rock lower surfaces and clear polycarbonate upper surfaces. The spatial distribution of the calcium carbonate precipitation was imaged using time-lapse photography and the influence on flow pathways revealed from tracer transport imaging. In the large-scale experiment, hydraulic aperture was reduced from 276 to 22 μm, corresponding to a transmissivity reduction of 1.71 × 10-5 to 8.75 × 10-9 m2/s, over a period of 12 days under constantly flowing conditions. With a modified injection strategy a similar three orders of magnitude reduction in transmissivity was achieved over a period of 3 days. Calcium carbonate precipitated over the entire artificial fracture with strong adhesion to both upper and lower surfaces and precipitation was controlled to prevent clogging of the injection well by manipulating the injection fluid velocity. These experiments demonstrate that microbially induced carbonate precipitation can successfully be used to grout a fracture under constantly flowing conditions and may be a viable alternative to cement based grouts when a high level of hydraulic sealing is required and chemical grouts when a more durable grout is required.

  1. Grouted Connections with Shear Keys

    DEFF Research Database (Denmark)

    Pedersen, Ronnie; Jørgensen, M. B.; Damkilde, Lars

    2012-01-01

    This paper presents a finite element model in the software package ABAQUS in which a reliable analysis of grouted pile-to-sleeve connections with shear keys is the particular purpose. The model is calibrated to experimental results and a consistent set of input parameters is estimated so that dif...... that different structural problems can be reproduced successfully....

  2. Grouting for Pile Foundation Improvement

    NARCIS (Netherlands)

    Van der Stoel, A.E.C.

    2001-01-01

    The aim of this research was to examine the use of grouting methods for pile foundation improvement, a generic term that is used here to define both foundation renovation (increasing the bearing capacity of a pile foundation that has insufficient bearing capacity) and foundation protection

  3. Design procedure for formulating and assessing the durability of particulate grouts

    International Nuclear Information System (INIS)

    Okonkwo, I.O.; Altschaeff, A.G.

    1989-01-01

    The current disposal plans for low-level wastes call for stabilizing or encapsulating and storing of these wastes in steel drums which in turn are buried in shallow trenches. Complete sealing is accomplished with grout, a liquid injection comprising principally of cement and fly ash, etc. Upon solidification, the grout forms a rigid mass around the drum, thereby eliminating access of groundwater into or out of the waste barrier, or leaching of radionuclides. Since the primary mechanism for the likely introduction of hazardous and/or radioactive elements into the biosphere in this situation, is through physical or chemical deterioration of the waste barrier, it is necessary that the effect of adverse environments on the durability of the grouts be examined and incorporated in barrier design. Currently, procedures for formulating grout mixes to assure a given impermeability or durability of the grout over its service period is lacking, and so are the techniques for monitoring the in-service performance of waste barrier systems. This paper depicts a serious limitation in waste barrier system technology, for it is time that optimization in design be possible. To allow this, a method is needed that creates the grout formulation specification for an optimization of behavior parameters in the resulting product. These considerations suggest a strong need for improvement in the grout formulation specification to allow a focus upon behavior properties desired by the engineer in the creation of optimum performance. This paper addresses these problems

  4. Parameters Optimization of Curtain Grouting Reinforcement Cycle in Yonglian Tunnel and Its Application

    Directory of Open Access Journals (Sweden)

    Qingsong Zhang

    2015-01-01

    Full Text Available For practical purposes, the curtain grouting method is an effective method to treat geological disasters and can be used to improve the strength and permeability resistance of surrounding rock. Selection of the optimal parameters of grouting reinforcement cycle especially reinforcement cycle thickness is one of the most interesting areas of research in curtain grouting designs. Based on the fluid-structure interaction theory and orthogonal analysis method, the influence of reinforcement cycle thickness, elastic modulus, and permeability on water inflow of tunnel after grouting and stability of surrounding rock was analyzed. As to the water inflow of tunnel after grouting used as performance evaluation index of grouting reinforcement cycle, it can be concluded that the permeability was the most important factor followed by reinforcement cycle thickness and elastic modulus. Furthermore, pore water pressure field, stress field, and plastic zone of surrounding rock were calculated by using COMSOL software under different conditions of reinforcement cycle thickness. It also can be concluded that the optimal thickness of reinforcement cycle and permeability can be adopted as 8 m and 1/100 of the surrounding rock permeability in the curtain grouting reinforcement cycle. The engineering case provides a reference for similar engineering.

  5. Long-Term Mechanical Behavior of Nano Silica Sol Grouting

    Directory of Open Access Journals (Sweden)

    Dongjiang Pan

    2018-01-01

    Full Text Available The longevity of grouting has a significant effect on the safe and sustainable operation of many engineering projects. A 500-day experiment was carried out to study the long-term mechanical behavior of nano silica sol grouting. The nano silica sol was activated with different proportions of a NaCl catalyst and cured under fluctuating temperature and humidity conditions. The mechanical parameters of the grout samples were tested using an electrohydraulic uniaxial compression tester and an improved Vicat instrument. Scanning electron microscope, X-ray diffraction, and ultrasonic velocity tests were carried out to analyze the strength change micro-mechanism. Tests showed that as the catalyst dosage in the grout mix is decreased, the curves on the graphs showing changes in the weight and geometric parameters of the samples over time could be divided into three stages, a shrinkage stage, a stable stage, and a second shrinkage stage. The catalyst improved the stability of the samples and reduced moisture loss. Temperature rise was also a driving force for moisture loss. Uniaxial compressive stress-strain curves for all of the samples were elastoplastic. The curves for uniaxial compression strength and secant modulus plotted against time could be divided into three stages. Sample brittleness increased with time and the brittleness index increased with higher catalyst dosages in the latter part of the curing time. Plastic strength-time curves exhibit allometric scaling. Curing conditions mainly affect the compactness, and then affect the strength.

  6. Long-Term Mechanical Behavior of Nano Silica Sol Grouting

    Science.gov (United States)

    Zhang, Nong; Zhang, Chenghao; Qian, Deyu; Han, Changliang; Yang, Sen

    2018-01-01

    The longevity of grouting has a significant effect on the safe and sustainable operation of many engineering projects. A 500-day experiment was carried out to study the long-term mechanical behavior of nano silica sol grouting. The nano silica sol was activated with different proportions of a NaCl catalyst and cured under fluctuating temperature and humidity conditions. The mechanical parameters of the grout samples were tested using an electrohydraulic uniaxial compression tester and an improved Vicat instrument. Scanning electron microscope, X-ray diffraction, and ultrasonic velocity tests were carried out to analyze the strength change micro-mechanism. Tests showed that as the catalyst dosage in the grout mix is decreased, the curves on the graphs showing changes in the weight and geometric parameters of the samples over time could be divided into three stages, a shrinkage stage, a stable stage, and a second shrinkage stage. The catalyst improved the stability of the samples and reduced moisture loss. Temperature rise was also a driving force for moisture loss. Uniaxial compressive stress-strain curves for all of the samples were elastoplastic. The curves for uniaxial compression strength and secant modulus plotted against time could be divided into three stages. Sample brittleness increased with time and the brittleness index increased with higher catalyst dosages in the latter part of the curing time. Plastic strength-time curves exhibit allometric scaling. Curing conditions mainly affect the compactness, and then affect the strength. PMID:29337897

  7. Kaolinitic clay-based grouting demonstration

    International Nuclear Information System (INIS)

    McCloskey, A.L.; Barry, C.J.; Wilmoth, R.

    1997-01-01

    An innovative Kaolinitic Clay-Based Grouting Demonstration was performed under the Mine Waste Technology Program (MWTP), funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by the EPA and the U.S. Department of Energy (DOE). The objective of the technology was to demonstrate the effectiveness of kaolinitic clay-based grouting in reducing/eliminating infiltration of surface and shallow groundwater through fractured bedrock into underground mine workings. In 1993, the Mike Horse Mine was selected as a demonstration site for the field implementation and evaluation of the grouting technology. The mine portal discharge ranged between 114 to 454 liters per minute (30 to 120 gpm) of water containing iron, zinc, manganese, and cadmium at levels exceeding the National Drinking Water Maximum Contaminant Levels. The grout formulation was designed by the developer Morrison Knudsen Corporation/Spetstamponazhgeologia (MK/STG), in May 1994. Grout injection was performed by Hayward Baker, Inc. under the directive of MSE Technology Applications, Inc. (MSE-TA) during fall of 1994. The grout was injected into directionally-drilled grout holes to form a grout curtain at the project site. Post grout observations suggest the grout was successful in reducing the infiltration of the surface and shallow groundwater from entering the underground mine workings. The proceeding paper describes the demonstration and technology used to form the subsurface barrier in the fracture system

  8. Grouting aid for controlling the separation of water for cement grout for grouting vertical tendons in nuclear concrete pressure vessels

    International Nuclear Information System (INIS)

    Schupack, M.

    1976-01-01

    Considerable testing and development work has led to grouting procedures which can successfully grout 60 m and taller tendons in containment structures. The exaggerated water separation phenomena of strand tendons can be controlled by chemical admixtures using proper mixing and pumping procedures. Experience with both vertical six-bar tendons and large capacity strand type tendons are described. History, development work, characteristics of grout using the admixtures, mixing and pumping procedure, full scale tests and practical applications are included. (author)

  9. Design and Control of Chemical Grouting : Volume 3 - Engineering Practice

    Science.gov (United States)

    1983-04-01

    Recent improvements in the engineering practice of chemical grouting have provided increased confidence in this method of ground modification. Designers can significantly improve the success of chemical grouting by defining their grouting program obj...

  10. Rheological measurements on cement grouts

    International Nuclear Information System (INIS)

    Dalton, M.J.

    1986-06-01

    This report describes the techniques which have been developed at Winfrith for assessing the rheological properties of cement grouts. A discussion of the theory of rheology and its application to cement is given and the methodology for calibrating a special paddle measuring system for a commercial viscometer is described. The use of the system for determining flow curves, equilibrium viscosity, viscosity as a function of shearing time and structure changes is also discussed. (author)

  11. In-situ thermeolectric stabilization of radioactive wastes

    International Nuclear Information System (INIS)

    Brouns, R.A.; Timmerman, C.L.

    1982-01-01

    Current analysis indicates that in situ vitrification is applicable to many wastes and soil types at a cost an order of magnitude less than exhumation, processing, and transportation to a deep geological disposal site. Once the waste materials have been solidified, future ground subsidence, wind erosion and plant or animal intrusion are virtually eliminated. Furthermore, the waste form is extremely durable

  12. Grouting as a remedial technique for buried low-level radioactive wastes

    International Nuclear Information System (INIS)

    Spalding, B.P.; Hyder, L.K.; Munro, I.L.

    1985-01-01

    Seven grout formulations were tested in the laboratory for their ability to penetrate and to reduce the hydraulic conductivities of soils used as backfills for shallow land burial trenches. Soils from two sites, in Oak Ridge, TN, and Maxey Flats, KY were used and both are classified as Typic Dystrochrepts. Three soluble grout formulations (sodium silicate, polypropenamide [polyacrylamide], and 1,3-Benzenediol [resorcinol]-formaldehyde) were able to both penetrate soil and sand columns and reduce hydraulic conductivities from initial values of ca. 10 -4 m s -1 to -8 m s -1 . Three particulate grouts (lime [calcium oxide]-fly ash, fly ash-cement-bentonite, and bentonite alone) could not penetrate columns; such formulations would, therefore, be difficult to inject into closed burial trenches. Field demonstrations with both sodium silicate and polyacrylamide showed that grout could be distributed throughout a burial trench and that waste-backfill hydraulic conductivity could be reduced several orders of magnitude. Field grouting with polyacrylamide reduced the mean hydraulic conductivity of nine intratrench monitoring wells from 10 -4 to 10 -8 m s -1 . Grouting of low-level radioactive solid waste in situ, therefore, should be an effective technique to correct situations where leaching of buried wastes has or will result in groundwater contamination

  13. Jet grouting for a groundwater cutoff wall in difficult glacial soil deposits

    International Nuclear Information System (INIS)

    Flanagan, R.F.; Pepe, F. Jr.

    1997-01-01

    Jet grouting is being used as part of a groundwater cutoff wall system in a major New York City subway construction project to limit drawdowns in an adjacent PCB contamination plume. A circular test shaft of jet grout columns was conducted during the design phase to obtain wall installation parameters. The test program also included shaft wall mapping, and measurements of; inflows, piezometric levels, ground heave and temperature, and jet grout hydraulic conductivity. An axisymmetric finite element method groundwater model was established to back calculate the in-situ hydraulic conductivities of both the surrounding glacial soils and the jet grout walls by matching observed inflows and piezometric levels. The model also verified the use of packer permeability test as a tool in the field to evaluate the hydraulic conductivities of jet grout columns. Both the test program and analytic studies indicated that adjustments to the construction procedures would be required to obtain lower hydraulic conductivities of the jet grout walls for construction. A comparison is made with the conductivities estimated from the test program/analytic studies with those from the present construction

  14. Quality assurance plan for placement of cold-cap grout, demonstration vault, Hanford Grout Vault Program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, P.T.; Wakeley, L.D.; Ernzen, J.J.; Walley, D.M.

    1992-08-01

    During FY 91, the U.S. Army Engineer Waterways Experiment Station (WES) developed a grout to be used as a cold cap, a nonradioactive layer, between the solidified waste and the cover blocks of a demonstration waste disposal vault at the U.S. Department of Energy Hanford Facility. This document recommends requirements for a quality assurance (QA) plan for field mixing and placing of the cold-cap grout during final closure of the demonstration vault. Preplacement activities emphasize selection and testing of materials that will match the performance of materials used in the WES grout. Materials sources and applicable American Society of Testing and Materials, American Concrete Institute, and American Petroleum Institute specifications and requirements are provided. Archiving of physical samples of materials is essential, in addition to careful maintenance of test reports and laboratory data. Full-scale field trial mixing and a detailed preconstruction conference are recommended. Placement activities focus on production and placement of a grout that remains sufficiently constant throughout all batches and meets performance requirements. QA activities must be coordinated between the batch plant and delivery site. Recommended sampling during placement includes cylinders cast for subsequent tests of compressive strength and for nondestructive evaluation and prisms cast for monitoring volume stability. A minimum of two lifts is recommended. Postplacement activities include long-term monitoring of the properties of grout specimens cast during placement. Minimum testing of cylinders includes pulse velocity, fundamental frequency, and unconfined compressive strength. Monitoring characteristics of the microstructure also are recommended. The QA plan should designate an organization to have responsibility for maintaining complete records, reports, and archived samples, including details of deviations from plans written before field placement.

  15. Demonstration of In-Situ Stabilization of Buried Waste at Pit G-11 at the Brookhaven National laboratory Glass Pits Disposal Site

    International Nuclear Information System (INIS)

    Dwyer, B.P.; Gilbert, J.; Heiser, J.

    1999-01-01

    In 1989 BNL was added to the EPAs National Priorities List. The site is divided into seven operable units (OU). OU-I includes the former landfill area. The field task site is noted as the AOC 2C Glass Holes location. Beginning in the 1960s and continuing into the 1980s, BNL disposed of laboratory waste (glassware, chemicals and animal carcasses) in numerous shallow pits. The drivers for remediating the pits are; historical records that indicate hazardous materials may have been disposed of in the pits; ground water contamination down gradient of the pits; a test excavation of one of the glass holes that unearthed laboratory glass bottles with unidentified liquids still contained; and the fact that BNL rests atop an EPA designated sole-source aquifer. The specific site chosen for this demonstration was pit G-11. The requirements that lead to choosing this pit were; a well characterized pit and a relatively isolated pit where our construction operations would not impact on adjacent pits. The glass holes area, including pit G-11, was comprehensively surveyed using a suite of geophysical techniques (e.g., EM-31, EM-61, GPR). Prior to stabilizing the waste form a subsurface barrier was constructed to contain the entire waste pit. The pit contents were then stabilized using a cement grout applied via jet grouting. The stabilization was performed to make removal of the waste from the pit easier and safer in terms of worker exposure. The grouting process would mix and masticate the waste and grout and form a single monolithic waste form. This large monolith would then be subdivided into smaller 4 foot by 4 foot by 10-12 foot block using a demolition grout. The smaller blocks would then be easily removed from the site and disposed of in a CERCLA waste site

  16. Grout Placement and Property Evaluation for Closing Hanford High-Level Waste Tanks - Scale-Up Testing

    International Nuclear Information System (INIS)

    LANGTON, CHRISTINE

    2003-01-01

    Hanford has 149 single-shell high level waste (HLW) tanks that were constructed between 1943 and 1964. Many of these tanks have leaked or are suspected of leaking HLW into the soil above the ground water. Consequently, a major effort is ongoing to transfer the liquid portion of the waste to the 28 newer, double-shell tanks. Savannah River National Laboratory (SRNL) was tasked to develop grout formulations for the three-layer closure concept selected by CH2M HILL for closing Tank C-106. These grout formulations were also evaluated for use as fill materials in the next six tanks scheduled to be closed. The overall scope consisted of both bench-scale testing to confirm mix designs and scale-up testing to confirm placement properties. This report provides results of the scale-up testing for the three-phase tank closure strategy. It also contains information on grouts for equipment and riser filling. The three-phase fill strategy is summarized as follows: Phase I fill encapsulates and minimizes dispersion of the residual waste in the tank. This fill is referred to as the Stabilization Layer and consists of the Stabilization Grout. The Phase II fill provides structural stability to the tank system and prevents subsidence. It is referred to as the Structural Layer and consists of the Structural Grout. A final Phase III fill consists of a grout designed to provide protection against intrusion and is referred to as the Capping Layer or Capping Grout

  17. In Situ Study of Thermal Stability of Copper Oxide Nanowires at Anaerobic Environment

    Directory of Open Access Journals (Sweden)

    Lihui Zhang

    2014-01-01

    Full Text Available Many metal oxides with promising electrochemical properties were developed recently. Before those metal oxides realize the use as an anode in lithium ion batteries, their thermal stability at anaerobic environment inside batteries should be clearly understood for safety. In this study, copper oxide nanowires were investigated as an example. Several kinds of in situ experiment methods including in situ optical microscopy, in situ Raman spectrum, and in situ transmission electron microscopy were adopted to fully investigate their thermal stability at anaerobic environment. Copper oxide nanowires begin to transform as copper(I oxide at about 250°C and finish at about 400°C. The phase transformation proceeds with a homogeneous nucleation.

  18. Investigation of a Hardened Cement Paste Grout

    DEFF Research Database (Denmark)

    Esteves, Luis Pedro; Sørensen, Eigil Verner

    This report documents a series of tests performed on a hardened cement paste grout delivered by the client, Det Norske Veritas A/S.......This report documents a series of tests performed on a hardened cement paste grout delivered by the client, Det Norske Veritas A/S....

  19. Jet Grouting. Control of execution and result parameters. Test fields - Experience in Chile

    International Nuclear Information System (INIS)

    Ayarza, P. M.; Vukotic, G.

    2014-01-01

    This article emphasizes the importance of Test Fields in project that includes the Jet Grouting technique. In particular, the Chilean experience is analyzed, where the Jet Grouting was first introduced by Pilots Terratest S. A. in the year 2010, only, only in 2011 the first project using jet columns was constructed. The versatilely of this technique allows its use in a wide variety of projects, for example, soil capacity improvement, settlement control, reduction of soil permeability and other environmental applications. Currently, the most common applications are underpinning existing foundations, ground improvement, lateral support of excavations, hydraulic barriers, slope stabilization, liquefaction control, among others. The Jet Grouting is one of the most demanding soil improvement technique and requires excellence in designing and execution engineers and other involved specialist. It is therefore essential to ensure exhaustive control to the execution and final parameters, in order to check that the product- Jet Grouting element-have the design properties, and implement modifications if necessary. Many authors strongly advises that if there is no comparable experience and even if there is, a Test Field of Jet Grouting elements has to be executed in site. This field consists in a nearby area with similar geotechnical conditions of the project, where Jet Grouting test columns will be constructed. This Test Field will allow selecting the most effective execution parameters and verifying that the final product has he correct design properties. (Author)

  20. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1992-07-01

    The Grout Treatment Facility (GTF) will provide permanent disposal for approximately 43 Mgal of low-level radioactive liquid waste currently being stored in underground tanks on the Hanford Site. The first step in permanent disposal is accomplished by solidifying the liquid waste with cementitious dry materials. The resulting grout is cast within underground vaults. This report on the GTF contains information on the following: Geologic data, hydrologic data, groundwater monitoring program, information, detection monitoring program, groundwater characterization drawings, building emergency plan--grout treatment facility, response action plan for grout treatment facility, Hanford Facility contingency plan, training course descriptions, overview of the Hanford Facility Grout Performance, assessment, bland use and zoning map, waste minimization plan, cover design engineering report, and clay liners (ADMIXTURES) in semiarid environments

  1. Field grouting summary report on the WAG 4 seeps 4 and 6 removal action project, Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 2: Appendixes A--D

    International Nuclear Information System (INIS)

    1997-05-01

    During the summer of 1996, a unique multi-phase, multi-stage, low-pressure permeation grouting pilot program was performed inside portions of four unlined waste disposal trenches at Waste Area Grouping (WAG) 4 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The project was deemed a non-time-critical removal action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); however, due to a history of heavy precipitation in the fall, the schedule was fast-tracked to meet an October 31, 1996 grouting completion data. The technical objective of the removal action was to reduce the off-site transport of Strontium 90 ( 90 Sr) by grouting portions of four waste disposal trenches believed to be responsible for over 70% of the 90 Sr leaving the site. A goal of the grouting operation was to reduce the average in situ hydraulic conductivity of the grouted waste materials to a value equal to or less than 1 X 10 -6 cm/sec. This target hydraulic conductivity value was established to be at least two orders of magnitude lower than that of the surrounding natural ground. The main report describes brief background to the project, describes and analyzes the grouting operations, draws conclusions from the work performed, and presents some of the lessons learned. Appendices contain: (A) pipe driving records; (B) casing grout injection records; (C) in-situ hydraulic conductivity testing records; and (D) grout quality control testing records

  2. Feasibility of permeation grouting for constructing subsurface barriers

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1994-03-01

    The technical feasibility of emplacing a barrier beneath a waste site using directionally drilled boreholes and permeation grouting was investigated. The benefits of this emplacement system are: (1) Directionally drilled boreholes provide access beneath a waste site without disturbing the waste; (2) interim containment of contaminants allows time for the development of remediation options; (3) in the interim, the volume of waste remains fixed; (4) barriers may enhance the effectiveness of in situ remediation actions; and (5) barrier systems may provide permanent waste containment

  3. Design for rock grouting based on analysis of grout penetration. Verification using Aespoe HRL data and parameter analysis

    International Nuclear Information System (INIS)

    Kobayashi, Shinji; Stille, Haakan

    2007-01-01

    Grouting as a method to reduce the inflow of water into underground facilities will be important in both the construction and operation of the deep repository. SKB has been studying grouting design based on characterization of fractured rock and prediction of grout spread. However, as in other Scandinavian tunnels, stop criteria have been empirically set so that grouting is completed when the grout flow is less than a certain value at maximum pressure or the grout take is above a certain value. Since empirically based stop criteria are determined without a theoretical basis and are not related to grout penetration, the grouting result may be inadequate or uneconomical. In order to permit the choice of adequate and cost-effective grouting methods, stop criteria can be designed based on a theoretical analysis of grout penetration. The relationship between grout penetration and grouting time has been studied at the Royal Institute of Technology and Chalmers University of Technology. Based on these studies, the theory has been further developed in order to apply to real grouting work. Another aspect is using the developed method for parameter analysis. The purpose of parameter analysis is to evaluate the influence of different grouting parameters on the result. Since the grouting strategy is composed of many different components, the selection of a grouting method is complex. Even if the theoretically most suitable grouting method is selected, it is difficult to carry out grouting exactly as planned because grouting parameters such as grout properties can easily vary during the grouting operation. In addition, knowing the parameters precisely beforehand is impossible because there are uncertainties inherent in the rock mass. Therefore, it is important to asses the effects of variations in grouting parameters. The parameter analysis can serve as a guide in choosing an effective grouting method. The objectives of this report are to: Further develop the theory concerning

  4. In-situ stabilization of radioactive zirconium swarf

    Science.gov (United States)

    Hess, Clay C.

    1999-01-01

    The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes.

  5. Stabilization of microorganisms for in situ degradation of toxic chemicals

    International Nuclear Information System (INIS)

    Crawford, R.L.; Ralston, D.R.

    1993-01-01

    Methods for large-scale microencapsulation of bacteria and nutrients into microbeads with small enough diameters to travel through aquifers have been developed at the University of Idaho. Both free and immobilized cells of Flavobacterium ATCC 39723, a gram-negative aerobe that degrades various chlorinated phenols, into aquifer microcosms, through which pentachlorophenol (PCP)-contaminated groundwater flowed at in situ flow rates. Aquifer samples were collected with an auger from three wells at the University of Idaho Ground Water Research Site, and packed into 24 columns. Some sterile columns were also prepared, by irradiation at the Washington State University Radiation Center. In some of the columns the free Flavobacterium cells were mixed with the aquifer material before packing the columns. In others, agarose-microimmobilized Flavobacterium were mixed into the aquifer material. The effluent from each column was collected daily for 170 days and analyzed by UV spectroscopy or HPLC for remaining PCP. There were no statistically significant differences between the degradation rates of free or encapsulated Flavobacterium in sterile or native aquifer material as tested in these experiments. This work has shown at the lab scale that encapsulated PCP-degrading Flavobacterium were able to survive under conditions of starvation, predation, and lack of water

  6. Superfund Innovative Technology Evaluation - Demonstration Bulletin: In-Situ Soil Stabilization

    Science.gov (United States)

    In-situ stabilization technology immobilizes organics and inorganic compounds in wet or dry soils by using reagents (additives) to polymerize with the soils and sludges producing a cement-like mass. Two basic components of this technology are the Geo-Con/DSM Deep Soil Mixing Sy...

  7. Innovative grout/retrieval demonstration final report

    International Nuclear Information System (INIS)

    Loomis, G.G.; Thompson, D.N.

    1995-01-01

    This report presents the results of an evaluation of an innovative retrieval technique for buried transuranic waste. Application of this retrieval technique was originally designed for full pit retrieval; however, it applies equally to a hot spot retrieval technology. The technique involves grouting the buried soil waste matrix with a jet grouting procedure, applying an expansive demolition grout to the matrix, and retrieving the debris. The grouted matrix provides an agglomeration of fine soil particles and contaminants resulting in an inherent contamination control during the dusty retrieval process. A full-scale field demonstration of this retrieval technique was performed on a simulated waste pit at the Idaho National Engineering Laboratory. Details are reported on all phases of this proof-of-concept demonstration including pit construction, jet grouting activities, application of the demolition grout, and actual retrieval of the grouted pit. A quantitative evaluation of aerosolized soils and rare earth tracer spread is given for all phases of the demonstration, and these results are compared to a baseline retrieval activity using conventional retrieval means. 8 refs., 47 figs., 10 tabs

  8. Assessment of annual exposure for grout operations

    International Nuclear Information System (INIS)

    Potter, R.E.

    1994-01-01

    An analysis is presented of the direct radiation exposures and dose rates to personnel from assumed quantities of radioactive grout, and Double Shell Tank (DST) waste feed. This analysis was based on filling four disposal vaults per year. Whole body doses were analyzed for occupational workers assigned to the Grout Treatment Facility (GTF). The study makes assumptions that must be met by the facility. Otherwise, the GTF will meet all DOE and WHC direct radiation exposure criteria. This analysis will be published in the Grout Final Safety Analysis Report (FSAR)

  9. Nuclear waste viewed in a new light; a synchrotron study of uranium encapsulated in grout

    Energy Technology Data Exchange (ETDEWEB)

    Stitt, C.A., E-mail: Camilla.stitt@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Hart, M., E-mail: oxford.mike@gmail.com [Diamond Light Source Limited, Harwell Science and Innovation Campus, Fermi Avenue, Didcot, Oxfordshire OX11 0QX (United Kingdom); Harker, N.J., E-mail: nicholas.harker@esrf.fr [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Hallam, K.R., E-mail: k.r.hallam@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); MacFarlane, J., E-mail: james.macfarlane@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Banos, A., E-mail: antonis.banos@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Paraskevoulakos, C., E-mail: cp13846@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Butcher, E., E-mail: ed.j.butcher@nnl.co.uk [National Nuclear Laboratory, Seascale, Cumbria CA20 1 PG (United Kingdom); Padovani, C., E-mail: cristiano.padovani@nda.gov.uk [Radioactive Waste Management Limited (formerly the Radioactive Waste Management Directorate of the UK Nuclear Decommissioning Authority), Curie Avenue, Didcot, Oxfordshire OX11 0RH (United Kingdom); Scott, T.B., E-mail: t.b.scott@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)

    2015-03-21

    Highlights: • Unirradiated Magnox uranium was encapsulated in grout and exposed to hydrogen. • Synchrotron X-ray tomography imaged the uranium corrosion before and after exposure. • Synchrotron X-ray powder diffraction identified the corrosion products; UH{sub 3} and UO{sub 2}. • Uranium encapsulated in grout oxidised via the anoxic U + H{sub 2}O regime. • Successful in-situ, non-invasive examination of pyrophoric and radioactive material - Abstract: How do you characterise the contents of a sealed nuclear waste package without breaking it open? This question is important when the contained corrosion products are potentially reactive with air and radioactive. Synchrotron X-rays have been used to perform micro-scale in-situ observation and characterisation of uranium encapsulated in grout; a simulation for a typical intermediate level waste storage packet. X-ray tomography and X-ray powder diffraction generated both qualitative and quantitative data from a grout-encapsulated uranium sample before, and after, deliberately constrained H{sub 2} corrosion. Tomographic reconstructions provided a means of assessing the extent, rates and character of the corrosion reactions by comparing the relative densities between the materials and the volume of reaction products. The oxidation of uranium in grout was found to follow the anoxic U + H{sub 2}O oxidation regime, and the pore network within the grout was observed to influence the growth of uranium hydride sites across the metal surface. Powder diffraction analysis identified the corrosion products as UO{sub 2} and UH{sub 3}, and permitted measurement of corrosion-induced strain. Together, X-ray tomography and diffraction provide means of accurately determining the types and extent of uranium corrosion occurring, thereby offering a future tool for isolating and studying the reactions occurring in real full-scale waste package systems.

  10. Fatigue Life of High Performance Grout for Wind Turbine Grouted Connection in Wet or Dry Environment

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.; Westhof, Luc; Yde, Elo

    Grouted connections of monopile supported offshore wind turbine structures are subjected to loads leading to very high oscillating service stresses in the grout material. The fatigue capacity of a high performance cement based grout was tested by dynamic compressive loading of cylindrical specimens...... at varying levels of cyclic frequency and load. The fatigue tests were performed in two series: one with the specimens in air and one with the specimens submerged in water during the test. The fatigue life of the grout, in terms of the number of cycles to failure, was found to be significantly shorter when...... tested in water than when tested in air....

  11. Fatigue Life of High Performance Grout in Dry and Wet Environment for Wind Turbine Grouted Connections

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    2011-01-01

    The cementitious material in grouted connections of offshore monopile wind turbine structures is subjected to very high oscillating service stresses. The fatigue capacity of the grout therefore becomes essential to the performance and service life of the grouted connection. In the present work...... the fatigue life of a high performance cement based grout was tested by dynamic compressive loading of cylindrical specimens at varying levels of cyclic frequency and load. The fatigue tests were performed in two series, one with the specimens tested in air and one with the specimens submerged in water during...

  12. Preliminary data on rheological limits for grouts in the Transportable Grout Facility

    International Nuclear Information System (INIS)

    Gilliam, T.M.; McDaniel, E.W.; Dole, L.R.; West, G.A.

    1987-04-01

    This report describes a method for establishing rheological limits for grouts that can be pumped in the Hanford Transportable Grout Facility (TGF). This method is based on two models that require determining two key parameters - gel strength and density. This work also presents rheological data on grouts prepared with simulated customer phosphate wastes (CPW) and double shell slurry (DSS) from the Hanford complex. These data can be used to make preliminary estimates of operating rheological limits of the TFG grouts. The suggested design limits will include safety factors that will increase these limits significantly. 4 refs

  13. Review of results from SKB R and D on grouting technology for sealing the rock, years 1996-2000

    International Nuclear Information System (INIS)

    Boden, A.; Eklund, D.; Eriksson, Magnus; Lagerblad, B.; Lindblom, U.

    2001-05-01

    rock mechanical analyses should be carried through already at the planning stage. The subproject 'Cement based grouting material' is divided into three parts. The part 'Inventory and characterisation of material' has mainly dealt with finely ground cements and different types of super plasticizers. The biggest durability problem regarding cement-based grouts is that they contain water-soluble components. Durability will mainly be a function water penetration through the grouted zone. This will, in turn, depend on the coefficient of fullness in the fracture system and the permeability of the stiffened grout. Therefore, a valuation of leaching and durability has to be based on studies of grout in fractures in the rock and calcium content of the penetrating water. Grout based on granulated blast-furnace slag and/or silica fume contains less calcium hydroxide, which decreases the leaching. These cements are, however, very slow if they aren't accelerated. The part 'Filtration stability' has mainly dealt with the development of a measuring method and model for characterisation and quantification of important material parameters concerning the filtration stability of cement based grouting materials. A three dimensional Bingham model and its connection to the grouting process have been presented. The newly developed rheological measuring method has made it possible to numerically compute the material constants included in the model. The proposal of how to measure and characterise the cement based grouting material is judged as successful

  14. Grout formulations for nuclear-waste isolation

    International Nuclear Information System (INIS)

    Buck, A.D.; Mather, K.

    1982-06-01

    It is imperative that control parameters for a grout mixture such as flow time, setting time, compressive strength, permeability, or combinations of these or of other properties be specified before a grout mixture is formulated and used. Once such parameters have been specified, it is possible to proportion a hydraulic cement-based grout mixture to meet the applicable requirements. This may be from experience or by trial mixtures or by both. While longevity of cemetitious mixtures in nonaggressive environments is known from history, satisfactory data involving specific mixtures in selected environments are still needed. Such testing is underway. While compatibility, especially long-term compatibility, of cemetitious mixtures with various rock types is also known, it is necessary to have such evidence for specific mixtures in contact with specific rocks in a selected environment or environments. Satisfactory grout mixtures may be proportioned using the standard practice set forth in Appendix A

  15. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1992-07-01

    The Grout Treatment Facility (GTF) will provide permanent disposal for approximately 43 Mgal of radioactive liquid waste currently being stored in underground tanks on the Hanford Site. The first step in permanent disposal is accomplished by solidifying the liquid waste with cementitious dry materials. The resulting grout is cast within underground vaults. This report on the GTF contains information on the following: Vault design, run-on/run-off control design, and asphalt compatibility with 90-degree celsius double-shell slurry feed

  16. Strength of Mock-up Trial Grout

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes tests carried out on samples taken and cast during the execution of a mock-up trial placement of the high performance grout MASTERFLOW 9500 on January 21, 2009.......The present report describes tests carried out on samples taken and cast during the execution of a mock-up trial placement of the high performance grout MASTERFLOW 9500 on January 21, 2009....

  17. A study of grout flow pattern analysis

    International Nuclear Information System (INIS)

    Lee, S. Y.; Hyun, S.

    2013-01-01

    A new disposal unit, designated as Salt Disposal Unit no. 6 (SDU6), is being designed for support of site accelerated closure goals and salt nuclear waste projections identified in the new Liquid Waste System plan. The unit is cylindrical disposal vault of 380 ft diameter and 43 ft in height, and it has about 30 million gallons of capacity. Primary objective was to develop the computational model and to perform the evaluations for the flow patterns of grout material in SDU6 as function of elevation of grout discharge port, and slurry rheology. A Bingham plastic model was basically used to represent the grout flow behavior. A two-phase modeling approach was taken to achieve the objective. This approach assumes that the air-grout interface determines the shape of the accumulation mound. The results of this study were used to develop the design guidelines for the discharge ports of the Saltstone feed materials in the SDU6 facility. The focusing areas of the modeling study are to estimate the domain size of the grout materials radially spread on the facility floor under the baseline modeling conditions, to perform the sensitivity analysis with respect to the baseline design and operating conditions such as elevation of discharge port, discharge pipe diameter, and grout properties, and to determine the changes in grout density as it is related to grout drop height. An axi-symmetric two-phase modeling method was used for computational efficiency. Based on the nominal design and operating conditions, a transient computational approach was taken to compute flow fields mainly driven by pumping inertia and natural gravity. Detailed solution methodology and analysis results are discussed here

  18. Description of the grout system dynamic simulation

    International Nuclear Information System (INIS)

    Zimmerman, B.D.

    1993-07-01

    The grout system dynamic computer simulation was created to allow investigation of the ability of the grouting system to meet established milestones, for various assumed system configurations and parameters. The simulation simulates the movement of tank waste through the system versus time, from initial storage tanks, through feed tanks and the grout plant, then finally to a grout vault. The simulation properly accounts for the following (1) time required to perform various actions or processes, (2) delays involved in gaining regulatory approval, (3) random system component failures, (4) limitations on equipment capacities, (5) available parallel components, and (6) different possible strategies for vault filling. The user is allowed to set a variety of system parameters for each simulation run. Currently, the output of a run primarily consists of a plot of projected grouting campaigns completed versus time, for comparison with milestones. Other outputs involving any model component can also be quickly created or deleted as desired. In particular, sensitivity runs where the effect of varying a model parameter (flow rates, delay times, number of feed tanks available, etc.) on the ability of the system to meet milestones can be made easily. The grout system simulation was implemented using the ITHINK* simulation language for Macintosh** computers

  19. Gas generation from Hanford grout samples

    International Nuclear Information System (INIS)

    Jonah, C.D.; Kapoor, S.; Matheson, M.S.; Mulac, W.A.; Meisel, D.

    1996-01-01

    In an extension of our work on the radiolytic processes that occur in the waste tanks at the Hanford site, we studied the gas generation from grout samples that contained nuclear waste simulants. Grout is one option for the long-term storage of low-level nuclear waste solutions but the radiolytic effects on grout have not been thoroughly defined. In particular, the generation of potentially flammable and hazardous gases required quantification. A research team at Argonne examined this issue and found that the total amount of gases generated radiolytically from the WHC samples was an order of magnitude higher than predicted. This implies that novel pathways fro charge migration from the solid grout to the associated water are responsible for gas evolution. The grout samples produced hydrogen, nitrous oxide, and carbon monoxide as well as nitrogen and oxygen. Yields of each of these substances were determined for doses that are equivalent to about 80 years storage of the grout. Carbon monoxide, which was produced in 2% yield, is of particular importance because even small amounts may adversely affect catalytic conversion instrumentation that has been planned for installation in the storage vaults

  20. Acoustic tomography and 3-D resistivity imaging of grout filled waste cells

    International Nuclear Information System (INIS)

    Morgan, F.D.; Chauvelier, C.; Shi, Weiqun; Lesmes, D.

    1997-01-01

    The Scientific Ecology Group, Inc., (SEG) was contracted by Martin Marietta Energy Systems, Inc., to demonstrate and evaluate four grout compounds for use in stabilizing radioactive waste trenches at the Oak Ridge National Laboratory (ORNL). The demonstration site was constructed at SEG's Gallaher Road test facility in Kingston, Tennessee. SEG's objectives in this project were to compare the effectiveness of the candidate grouts and grouting procedures to hydrologically isolate the waste contained within the trenches and to stabilize the trenches against subsequent subsidence. In a separate agreement with Martin Marietta Energy Systems, MIT was contracted to demonstrate the feasibility of using high-frequency acoustic tomographic imaging to evaluate the performance of the various grouts and grouting procedures, and to monitor the stability of the grouted test cells over time. The test trench consisted of four contiguous cells, each 14 feet long x 12 feet wide x 12 feet deep. The native soil in which the test cells were constructed consisted of fine red clay which is typical of the Oak Ridge area. A plan view of the test cells is shown in Figure 1 , and a cross-sectional view of one of the cells within the trench. Each cell within the trench was filled with approximately 75 cubic yards of simulated waste. The simulated waste, which included 55 gallon drums and HEPA filters, consisted of approximately 35% metal, 15% wood, and 50% paper/plastic. After the cells were loaded with the simulated waste, the trench was covered by three feet of soil to grade, to duplicate the trench configuration commonly found at ORNL

  1. CEMENTITIOUS GROUT FOR CLOSING SRS HIGH LEVEL WASTE TANKS - #12315

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Burns, H.; Stefanko, D.

    2012-01-10

    In 1997, the first two United States Department of Energy (US DOE) high level waste tanks (Tanks 17-F and 20-F: Type IV, single shell tanks) were taken out of service (permanently closed) at the Savannah River Site (SRS). In 2012, the DOE plans to remove from service two additional Savannah River Site (SRS) Type IV high-level waste tanks, Tanks 18-F and 19-F. These tanks were constructed in the late 1950's and received low-heat waste and do not contain cooling coils. Operational closure of Tanks 18-F and 19-F is intended to be consistent with the applicable requirements of the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and will be performed in accordance with South Carolina Department of Health and Environmental Control (SCDHEC). The closure will physically stabilize two 4.92E+04 cubic meter (1.3 E+06 gallon) carbon steel tanks and isolate and stabilize any residual contaminants left in the tanks. The closure will also fill, physically stabilize and isolate ancillary equipment abandoned in the tanks. A Performance Assessment (PA) has been developed to assess the long-term fate and transport of residual contamination in the environment resulting from the operational closure of the F-Area Tank Farm (FTF) waste tanks. Next generation flowable, zero-bleed cementitious grouts were designed, tested, and specified for closing Tanks 18-F and 19-F and for filling the abandoned equipment. Fill requirements were developed for both the tank and equipment grouts. All grout formulations were required to be alkaline with a pH of 12.4 and chemically reduction potential (Eh) of -200 to -400 to stabilize selected potential contaminants of concern. This was achieved by including Portland cement and Grade 100 slag in the mixes, respectively. Ingredients and proportions of cementitious reagents were selected and adjusted, respectively, to support the mass placement strategy developed by

  2. PENGARUH PENAMBAHAN SIKA GROUT PADA MORTAR SEBAGAI BAHAN GROUTING TERHADAP LEKATAN TULANGAN DALAM BETON DENGAN COPPER SLAG SEBAGAI CEMENTITIOUS

    Directory of Open Access Journals (Sweden)

    Mohammad Sulton

    2012-09-01

    Full Text Available Abstract: The Impact of Sika Grout Addition on Grouting Mortar Toward Concrete Reinforcement Stickness with Copper Slag as Cementitious. The aim of this research is to identify the impact of Sika Grout addition on grouting mortar toward concrete reinforcement stickness with copper slag as cementitious. The experiment result of this research shows that (1 the addition of Sika Grout 215 in grouting mortar can improve the reinforcement stickness; (2 the use of 100% Sika Grout 215 in grouting mortar produces maximum stickness; (3 the stickness of 100% Sika Grout 215 has 12.800 kg stronger (2,8% of improvement than those of using copper slag reinforcement (without grouting as 12.450 kg; (4 the use of less than 100% Sika Grout produces less stickness of no-grouting reinforcement; and (5 there is similar slip characteristic between  concrete reinforcement added with grouting and without grouting as 2,5 mm on outer part of the mortar.

  3. Autogenous healing properties of cement-based grouts

    International Nuclear Information System (INIS)

    Onofrei, M.; Roe, L.; Shenton, B.

    1997-05-01

    This report presents the results of a study conducted to provide information on the ability of cement-based grouts to self-seal. Autogenous sealing was investigated both on bulk grouts and in thin films of grouts. In both cases, the self-sealing capabilities of the cement-based grouts were investigated with water flowing through the grout. Autogenous sealing was studied through changes in pore structure (decrease in pore radius and volume of pores) and changes in the rate of water flow through the cement-based grouts. (author)

  4. Test plan for formulation and evaluation of grouted waste forms with shine process wastes

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, W. L. [Argonne National Lab. (ANL), Argonne, IL (United States); Jerden, J. L. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    The objective of this experimental project is to demonstrate that waste streams generated during the production of Mo99 by the SHINE Medical Technologies (SHINE) process can be immobilized in cement-based grouted waste forms having physical, chemical, and radiological stabilities that meet regulatory requirements for handling, storage, transport, and disposal.

  5. A new design concept of fully grouted rock bolts in underground construction

    Science.gov (United States)

    Phich Nguyen, Quang; Nguyen, Van Manh; Tuong Nguyen, Ke

    2018-04-01

    The main problem after excavating an underground excavation is to maintain the stability of the excavation for a certain period of time. Failure in meeting this demand is a threat to safety of men and equipment. Support and reinforcement are different instruments with different mechanisms. Among the common support systems in tunnelling and mining, rock bolts have been widely used to reinforce rock mass and also to reduce geological hazards. Furthermore rock bolts can be applied under varying different geological conditions with cost-effectiveness. Although different methods are developed for grouted rock bolts design until now, the interaction mechanism of the rock bolts and rock mass is still very complicated issue. The paper addresses an analytical model for the analysis and design of fully grouted rock bolts based on the reinforcement principle. According to this concept the jointed rock mass reinforced by grouted rock bolts is considered as composite material which includes rock mass, the grout material and the bolt shank. The mechanical properties of this composite material depend on the ratio of the components. The closed-form solution was developed based on the assumption that the rock mass arround a circular tunnel remained elastic after installing fully grouted rock bolts. The main parameters of the rock-bolt system (the diameter and length of bolt shank, the space between the bolts) are then easily estimated from the obtained solution.

  6. Grouting of fly ash in sanitary landfills; Injektering av flygaska i hushaallsavfallsdeponi

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Karin; Berg, Magnus [AaF-Energi och Miljoe AB, Stockhom (Sweden); Andreas, Lale; Lagerkvist, Anders [Luleaa Univ. of Technology (Sweden); Jannes, Sara; Tham, Gustav [Telge Aatervinning AB, Soedertaelje (Sweden); Sjoeblom, Rolf [Tekedo AB, Nykoeping (Sweden)

    2003-10-01

    The purpose of the study was to investigate the potential for stabilization of sanitary landfills by injecting fly ash. The method is supposed to prevent differential settlements in landfills and by that to counteract damages in the final cover. Injecting fly ash may also affect the chemical development in a positive way and prevent metal leaching. Pilot experiments at the Tveta waste recycling center (Tveta Aatervinningsanlaeggning) have been performed in order to estimate if the grouting technology is a suitable method for sanitary landfills. Fly ashes from the combustion of bio fuels were used in these tests. A literature study and laboratory experiments in order to prepare the field experiments were also part of the project. About 100 tons of ash slurry were injected during the pilot experiments. This corresponds to a filling degree of approximately 12-16 % of the available pores in the landfill body. As a result of the pilot test, the following conclusions can be drawn: Ash can be mixed with water to a pumpable slurry which can be injected without hardening inside the equipment. Neither the waste nor the grouting material caused a backpressure during the injection and nothing indicates that the injected ash deforms the landfilled waste. The ash-water-slurry flows through the voids in the waste easily. Thus, the ash may dispread quite far from the injection holes. Using a more powerful equipment backpressure and movements in the waste might occur. It was not possible to estimate the flow required for backpressure in this study. Large variations are possible but for safety reasons the maximal pressure should be limited with regard to the expected stability in the actual area. The grouted ash will harden within the landfill body within a couple of days. It accumulates in hard but brittle lumps, which may result in an increased stability of the landfill. Further studies are necessary in order to evaluate how the stability is affected and what amounts of ash are

  7. Rheology of sludge-slurry grouts

    International Nuclear Information System (INIS)

    McDaniel, E.W.

    1980-10-01

    A series of rheograms was developed that relates the critical velocity (velocity where flow changes from laminar to turbulent) of a cementitious grout that incorporates a suspended sludge-slurry to the critical velocity of a reference grout made with a simulated waste solution. The sludge that is now in the Gunite waste tanks at the Oak Ridge National Laboratory (ORNL) will be suspended and pumped to the new waste storage tanks in Melton Valley. The sludge will then be blended with a cement mix base to form a grout which will be injected underground by the shale fracturing process. This report describes the materials, equipment, and techniques used in the laboratory studies to suspend sludges and mix sludge-slurry grouts that have flow properties similar to those of current shale fracturing grouts. Bentonite clay is an effective suspender in dilute NaNO 3 solutions; 15 wt % solids can be suspended with 2.0 wt % bentonite in a 0.1 M NaNO 3 solution. Other suspending materials were evaluated, but bentonite gave the best results. If a slurry grout becomes too viscous to pump, methods must be available to thin the mixture. A number of thinners, friction reducers, and plasticizers were examined. Q-Broxin, a thinner supplied by Baroid, reduced the velocity of a grout required for turbulent flow in a 5.0-cm (2-in.)-diam tube from 1.76 to 1.20 m/s (5.79 to 3.95 ft/s); FX-32C, a plasticizer supplied by Fox Industries, Inc., reduced the velocity from 1.76 to 0.75 m/s

  8. Agar agar-stabilized milled zerovalent iron particles for in situ groundwater remediation

    Energy Technology Data Exchange (ETDEWEB)

    Velimirovic, Milica; Schmid, Doris; Wagner, Stephan; Micić, Vesna; Kammer, Frank von der; Hofmann, Thilo, E-mail: thilo.hofmann@univie.ac.at

    2016-09-01

    Submicron-scale milled zerovalent iron (milled ZVI) particles produced by grinding macroscopic raw materials could provide a cost-effective alternative to nanoscale zerovalent iron (nZVI) particles for in situ degradation of chlorinated aliphatic hydrocarbons in groundwater. However, the aggregation and settling of bare milled ZVI particles from suspension presents a significant obstacle to their in situ application for groundwater remediation. In our investigations we reduced the rapid aggregation and settling rate of bare milled ZVI particles from suspension by stabilization with a “green” agar agar polymer. The transport potential of stabilized milled ZVI particle suspensions in a diverse array of natural heterogeneous porous media was evaluated in a series of well-controlled laboratory column experiments. The impact of agar agar on trichloroethene (TCE) removal by milled ZVI particles was assessed in laboratory-scale batch reactors. The use of agar agar significantly enhanced the transport of milled ZVI particles in all of the investigated porous media. Reactivity tests showed that the agar agar-stabilized milled ZVI particles were reactive towards TCE, but that their reactivity was an order of magnitude less than that of bare, non-stabilized milled ZVI particles. Our results suggest that milled ZVI particles could be used as an alternative to nZVI particles as their potential for emplacement into contaminated zone, their reactivity, and expected longevity are beneficial for in situ groundwater remediation. - Highlights: • Rapid aggregation and sedimentation were observed in bare milled ZVI particles. • Agar agar improved the stability of milled ZVI particle suspensions. • Agar agar enhanced the transport of milled ZVI particles in heterogeneous sands. • Agar agar reduced the reactivity of milled ZVI particles towards TCE.

  9. Agar agar-stabilized milled zerovalent iron particles for in situ groundwater remediation

    International Nuclear Information System (INIS)

    Velimirovic, Milica; Schmid, Doris; Wagner, Stephan; Micić, Vesna; Kammer, Frank von der; Hofmann, Thilo

    2016-01-01

    Submicron-scale milled zerovalent iron (milled ZVI) particles produced by grinding macroscopic raw materials could provide a cost-effective alternative to nanoscale zerovalent iron (nZVI) particles for in situ degradation of chlorinated aliphatic hydrocarbons in groundwater. However, the aggregation and settling of bare milled ZVI particles from suspension presents a significant obstacle to their in situ application for groundwater remediation. In our investigations we reduced the rapid aggregation and settling rate of bare milled ZVI particles from suspension by stabilization with a “green” agar agar polymer. The transport potential of stabilized milled ZVI particle suspensions in a diverse array of natural heterogeneous porous media was evaluated in a series of well-controlled laboratory column experiments. The impact of agar agar on trichloroethene (TCE) removal by milled ZVI particles was assessed in laboratory-scale batch reactors. The use of agar agar significantly enhanced the transport of milled ZVI particles in all of the investigated porous media. Reactivity tests showed that the agar agar-stabilized milled ZVI particles were reactive towards TCE, but that their reactivity was an order of magnitude less than that of bare, non-stabilized milled ZVI particles. Our results suggest that milled ZVI particles could be used as an alternative to nZVI particles as their potential for emplacement into contaminated zone, their reactivity, and expected longevity are beneficial for in situ groundwater remediation. - Highlights: • Rapid aggregation and sedimentation were observed in bare milled ZVI particles. • Agar agar improved the stability of milled ZVI particle suspensions. • Agar agar enhanced the transport of milled ZVI particles in heterogeneous sands. • Agar agar reduced the reactivity of milled ZVI particles towards TCE.

  10. Mechanical Properties of High Cementitious Grout (I)

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

     The present report describes tests carried out on the high performance grout MASTERFLOW 9500, marked WMG 7145 FP, developed by BASF Construction Materials and designed for use in grouted connections of offshore windmill foundations....

  11. Grout Treatment Facility Land Disposal Restriction Management Plan

    International Nuclear Information System (INIS)

    Hendrickson, D.W.

    1991-01-01

    This document establishes management plans directed to result in the land disposal of grouted wastes at the Hanford Grout Facilities in compliance with Federal, State of Washington, and Department of Energy land disposal restrictions. 9 refs., 1 fig

  12. Corrosion performance of prestressing strands in contact with dissimilar grouts.

    Science.gov (United States)

    2013-01-01

    To improve the corrosion protection provided to prestressing strands, anti-bleed grouts are used to fill voids in post-tensioning : ducts that result from bleeding and shrinkage of older Portland Cement grouts. Environmental differences caused by exp...

  13. Mechanical Properties of High Performance Cementitious Grout Masterflow 9200

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes tests carried out on the high performance grout Masterflow 9200, developed by BASF Construction Chemicals A/S and designed for use in grouted connections of windmill foundations....

  14. Pressure grouting of fractured basalt flows

    International Nuclear Information System (INIS)

    Shaw, P.; Weidner, J.; Phillips, S.; Alexander, J.

    1996-04-01

    This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material

  15. Microbial analyses of cement and grouting additives

    International Nuclear Information System (INIS)

    Hallbeck, L.; Jaegevall, S.; Paeaejaervi, A.; Rabe, L.; Edlund, J.; Eriksson, S.

    2012-01-01

    During sampling in the ONKALO tunnel in 2006, heavy growth of a slimy material was observed in connection with grouting. It was suggested to be microbial growth on organic additives leaching from the grout. Two sampling campaigns resulted in the isolation of several aerobic bacterial strains. Some of these strains were used in biodegradation studies of three solid cement powders, eight liquid grout additives, and six plastic drainage materials. Degradation was also studied using ONKALO groundwaters as inoculums. The isolated strains were most closely related to hydrocarbon-degrading microorganisms. The biodegradation of seven of the products was tested using microorganisms isolated from the ONKALO slime in 2006; none of these strains could degrade the tested products. When ONKALO drillhole groundwaters were used as inoculums in the degradation studies, it was demonstrated that Structuro 111X, Mighty 150, and Super-Parmix supported growth of the groundwater microorganisms. Structuro 111X is a polycarboxylate condensate while Mighty 150 and Super-Parmix are condensates with formaldehyde and naphthalene. Some of the isolated microorganisms belonged to the genus Pseudomonas, many strains of which can degrade organic molecules. None of the plastic drainage materials supported growth during the degradation studies. Microorganisms were present in two of the liquid products when delivered, GroutAid and Super-Parmix. The potential of the organic compounds in grout additives to be degraded by microorganisms, increasing the risk of biofilm formation and complexing compound production, must be considered. Microbial growth will also increase the possibility of hydrogen sulphide formation. (orig.)

  16. Non-destructive examination of grouted waste

    International Nuclear Information System (INIS)

    Benny, H.L.

    1994-01-01

    This data report contains the results of ultrasonic pulse velocity (UPV) and unconfined compressive strength (USC) measurements on a grouted simulant of 106AN tank waste. This testing program was conducted according to the requirements detailed in WHC-1993a. If successful, these methods could lead to a system for the remote verification of waste form quality. The objectives of this testing program were: to determine if a relationship exists between the velocity of ultrasonic compression waves and the unconfined compressive strength of simulated grouted waste, and if so, determine if the relationship is a valid method for grout quality assessment; and to determine if a relationship exists between the attenuation of wave amplitude and the age of test specimens. The first objective was met, in that a relationship between the UPV waves and USC was determined. This method appears to provide a valid measure of the quality of the grouted waste, as discussed in Sections 3.0 and 4.0. The second objective, to determine if the attenuation of UPV waves was related to the age of test specimens was partially met. A relationship does exist between wave amplitude and age, but it is doubtful that this method alone can be used to verify the overall quality of grouted waste. Section 2.0 describes the test methods, with the results detailed in Section 3.0. A discussion of the results are provided in Section 4.0

  17. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1988-01-01

    The long-term performance of the grout disposal system for Phosphate/Sulfate Waste (PSW) was analyzed. PSW is a low-level liquid generated by activities associated with N Reactor operations. The waste will be mixed with dry solids and permanently disposed of as a cementitious grout in sub-surface concrete vaults at Hanford's 200-East Area. Two categories of scenarios were analyzed that could cause humans to be exposed to radionuclides and chemicals from the grouted waste: contaminated groundwater and direct intrusion. In the groundwater scenario, contaminants are released from the buried grout monoliths, then eventually transported via the groundwater to the Columbia River. As modeled, the contaminants are assumed to leach out of the monoliths at a constant rate over a 10,000-year period. The other category of exposure involves intruders who inadvertently contact the waste directly, either by drilling, excavating, or gardening. Long-term impacts that could result from disposal of PSW grout were expressed in terms of incremental increases of (1) chemical concentrations in the groundwater and surface waters, and (2) radiation doses. None of the calculated impacts exceeded the corresponding regulatory limits set by Washington State, Department of Energy, or the Nuclear Regulatory Commission

  18. Pressure grouting of fractured basalt flows

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, P.; Weidner, J.; Phillips, S.; Alexander, J.

    1996-04-01

    This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material.

  19. Jet Grouting. Control of execution and result parameters. Test fields - Experience in Chile; Jet Grouting. Control de parametros de ejecucion y de resultados. Campos de prueba-Experiencia en Chile

    Energy Technology Data Exchange (ETDEWEB)

    Ayarza, P. M.; Vukotic, G.

    2014-07-01

    This article emphasizes the importance of Test Fields in project that includes the Jet Grouting technique. In particular, the Chilean experience is analyzed, where the Jet Grouting was first introduced by Pilots Terratest S. A. in the year 2010, only, only in 2011 the first project using jet columns was constructed. The versatilely of this technique allows its use in a wide variety of projects, for example, soil capacity improvement, settlement control, reduction of soil permeability and other environmental applications. Currently, the most common applications are underpinning existing foundations, ground improvement, lateral support of excavations, hydraulic barriers, slope stabilization, liquefaction control, among others. The Jet Grouting is one of the most demanding soil improvement technique and requires excellence in designing and execution engineers and other involved specialist. It is therefore essential to ensure exhaustive control to the execution and final parameters, in order to check that the product- Jet Grouting element-have the design properties, and implement modifications if necessary. Many authors strongly advises that if there is no comparable experience and even if there is, a Test Field of Jet Grouting elements has to be executed in site. This field consists in a nearby area with similar geotechnical conditions of the project, where Jet Grouting test columns will be constructed. This Test Field will allow selecting the most effective execution parameters and verifying that the final product has he correct design properties. (Author)

  20. In situ stabilization of mixed radioactive waste storage tanks and contaminated soil areas

    International Nuclear Information System (INIS)

    Matthern, G.E.; Meservey, R.H.

    1997-01-01

    Within the Department of Energy (DOE) Complex, there are a number of small (<50,000 gallons) underground Storage tanks containing mixed waste materials. The radioactive content of wastes eliminates the feasibility for hazardous waste treatment in accordance with previously prescribed Resource Conservation and Recovery Act (RCRA) technologies. As a result, DOE is funding in situ stabilization technology development for these tanks, Some of this development work has been done at the Idaho National Engineering and Environmental Laboratory (INEEL) and the initial efforts there were concentrated on the stabilization of the contents of the Test Area North (TAN) V-9 Tank. This is a 400 gallon underground tank filled with about 320 gallons of liquids and silty sediments. Sampling data indicates that approximately 50 wt% of the tank contents is aqueous-phase liquids. The vertically oriented cylindrical tank has a conical bottom and a chordal baffle that separates the tank inlet from its outlet. Access to the tank is through a six inch diameter access pipe on top of the tank. Because of the high volume, and the high concentration of aqueous-phase materials, Tank V-9 stabilization efforts have focussed on applying in situ agitation with dry feed addition to stabilize its contents. Materials selected for dry feed addition to this tank include a mixture of Aquaset IIH, and Type I/II Portland cement. This paper describes the results of proof-of-concept tests performed on full scale mockups of the Tank V-9. This proof-of-concept test were used to set operating parameters for in situ mixing, as well as evaluate how variations in Aquaset IIH/Portland cement ratio and sediment to liquid volume affected mixing of the tank

  1. Assessment of the availability of As and Pb in soils after in situ stabilization.

    Science.gov (United States)

    Zhang, Wanying; Yang, Jie; Li, Zhongyuan; Zhou, Dongmei; Dang, Fei

    2017-10-01

    The in situ stabilization has been widely used to remediate metal-contaminated soil. However, the long-term retaining performance of heavy metals and the associated risk after in situ stabilization remains unclear and has evoked amounting concerns. Here, Pb- or As-contaminated soil was stabilized by a commercial amendment. The availability of Pb and As after in situ stabilization were estimated by ten different in vitro chemical extractions and DGT technique. After amendment application, a significant decline in extractable Pb or As was observed in treatments of Milli-Q water, 0.01 M CaCl 2 , 0.1 M NaNO 3 , 0.05 M (NH 4 ) 2 SO 4 , and 0.43 M HOAc. Potential available metal(loid)s determined by DGT also showed remarkable reduction. Meanwhile, the results of in vivo uptake assays demonstrated that Pb concentrations in shoots of ryegrass Lolium perenne L. declined to 12% of the control samples, comparable to the extraction ratio of 0.1 M NaNO 3 (15.8%) and 0.05 M (NH 4 ) 2 SO 4 (17.3%). For As-contaminated soil, 0.43 M HOAC provided a better estimation of relative phytoavailability (64.6 vs. 65.4% in ryegrass) compared to other extraction methods. We propose that 0.1 M NaNO 3 or 0.05 M (NH 4 ) 2 SO 4 for Pb and 0.43 M HOAc for As may serve as surrogate measures to estimate the lability of metal(loid)s after soil remediation of the tested contaminated soils. Further studies over a wider range of soil types and amendments are necessary to validate extraction methods.

  2. Mechanical Properties of High Performance Cementitious Grout (II)

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report is an update of the report “Mechanical Properties of High Performance Cementitious Grout (I)” [1] and describes tests carried out on the high performance grout MASTERFLOW 9500, marked “WMG 7145 FP”, developed by BASF Construction Chemicals A/S and designed for use in grouted...

  3. Hanford grout: predicting long-term performance

    International Nuclear Information System (INIS)

    Sewart, G.H.; Mitchell, D.H.; Treat, R.L.; McMakin, A.H.

    1987-01-01

    Grouted disposal is being planned for the low-level portion of liquid radioactive wastes at the Hanford site in Washington state. The performance of the disposal system must be such that it will protect people and the environment for thousands of years after disposal. To predict whether a specific grout disposal system will comply with existing and foreseen regulations, a performance assessment (PA) is performed. Long-term PAs are conducted for a range of performance conditions. Performance assessment is an inexact science. Quantifying projected impacts is especially difficult when only scant data exist on the behavior of certain components of the disposal system over thousands of years. To develop defensible results, we are honing the models and obtaining experimental data. The combination of engineered features and PA refinements is being used to ensure that Hanford grout will meet its principal goal: to protect people and the environment in the future

  4. Nuclear waste viewed in a new light; a synchrotron study of uranium encapsulated in grout.

    Science.gov (United States)

    Stitt, C A; Hart, M; Harker, N J; Hallam, K R; MacFarlane, J; Banos, A; Paraskevoulakos, C; Butcher, E; Padovani, C; Scott, T B

    2015-03-21

    How do you characterise the contents of a sealed nuclear waste package without breaking it open? This question is important when the contained corrosion products are potentially reactive with air and radioactive. Synchrotron X-rays have been used to perform micro-scale in-situ observation and characterisation of uranium encapsulated in grout; a simulation for a typical intermediate level waste storage packet. X-ray tomography and X-ray powder diffraction generated both qualitative and quantitative data from a grout-encapsulated uranium sample before, and after, deliberately constrained H2 corrosion. Tomographic reconstructions provided a means of assessing the extent, rates and character of the corrosion reactions by comparing the relative densities between the materials and the volume of reaction products. The oxidation of uranium in grout was found to follow the anoxic U+H2O oxidation regime, and the pore network within the grout was observed to influence the growth of uranium hydride sites across the metal surface. Powder diffraction analysis identified the corrosion products as UO2 and UH3, and permitted measurement of corrosion-induced strain. Together, X-ray tomography and diffraction provide means of accurately determining the types and extent of uranium corrosion occurring, thereby offering a future tool for isolating and studying the reactions occurring in real full-scale waste package systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Phase I - Laboratory Study Effects of Cement Grout Structures on Colloid Formation from SRS Soils

    International Nuclear Information System (INIS)

    Serkiz, S.M.

    2001-01-01

    Studies were conducted to better understand the influence of grout structures and fills on colloid formation. Low-Level Waste is disposed in concrete vaults and trenches at the E-Area Low-Level Waste Facility (LLWF). Two types of enhanced trench disposal are approved for use including; Intimately-Mixed Cement-Stabilized waste forms, such as Ashcrete and Blowcrete resulting from operation of the Consolidated Incinerator Facility, and Cement-Stabilized Encapsulated waste, where waste forms (e.g., contaminated equipment) will be surrounded by a grout or other cementitious material. The presence of concrete structures and process of grouting in trenches are expected to generate colloids, both from the grout itself and as a result of the interactions of these cementitious materials and their degradation products with the surrounding soils. The extent of occurrence, mobility, and influence on contaminant transport of colloidal materials in aquifer systems is the subject of this study. The intent of this study is not to modify the PA but to aid in our understanding of the significance of this phenomenon. Information generated in this study will help in considering whether colloid-enhanced contaminant migration should be considered in establishing waste acceptance criteria and in the design and development of waste disposal systems

  6. In situ evidence of mineral physical protection and carbon stabilization revealed by nanoscale 3-D tomography

    Science.gov (United States)

    Weng, Yi-Tse; Wang, Chun-Chieh; Chiang, Cheng-Cheng; Tsai, Heng; Song, Yen-Fang; Huang, Shiuh-Tsuen; Liang, Biqing

    2018-05-01

    An approach for nanoscale 3-D tomography of organic carbon (OC) and associated mineral nanoparticles was developed to illustrate their spatial distribution and boundary interplay, using synchrotron-based transmission X-ray microscopy (TXM). The proposed 3-D tomography technique was first applied to in situ observation of a laboratory-made consortium of black carbon (BC) and nanomineral (TiO2, 15 nm), and its performance was evaluated using dual-scan (absorption contrast and phase contrast) modes. This novel tool was then successfully applied to a natural OC-mineral consortium from mountain soil at a spatial resolution of 60 nm, showing the fine structure and boundary of OC, the distribution of abundant nano-sized minerals, and the 3-D organo-mineral association in situ. The stabilization of 3500-year-old natural OC was mainly attributed to the physical protection of nano-sized iron (Fe)-containing minerals (Fe oxyhydroxides including ferrihydrite, goethite, and lepidocrocite), and the strong organo-mineral complexation. In situ evidence revealed an abundance of mineral nanoparticles, in dense thin layers or nano-aggregates/clusters, instead of crystalline clay-sized minerals on or near OC surfaces. The key working minerals for C stabilization were reactive short-range-order (SRO) mineral nanoparticles and poorly crystalline submicron-sized clay minerals. Spectroscopic analyses demonstrated that the studied OC was not merely in crisscross co-localization with reactive SRO minerals; there could be a significant degree of binding between OC and the minerals. The ubiquity and abundance of mineral nanoparticles on the OC surface, and their heterogeneity in the natural environment may have been severely underestimated by traditional research approaches. Our in situ description of organo-mineral interplay at the nanoscale provides direct evidence to substantiate the importance of mineral physical protection for the long-term stabilization of OC. This high-resolution 3-D

  7. In situ optoacoustic measurement of the pointing stability of femtosecond laser beams

    Science.gov (United States)

    Pushkarev, D.; Mitina, E.; Uryupina, D.; Volkov, R.; Karabytov, A.; Savel'ev, A.

    2018-02-01

    A new method for the in situ acoustic measurement of the beam pointing stability (BPS) of powerful pulsed lasers is tested. A broadband (~6 MHz) piezoelectric transducer placed a few millimeters from the laser spark produces an electric pulse. We show that variation in time of the position of this pulse can be used to assess the BPS down to 1 µrad in a few hundred laser shots. The estimated value coincides well with the BPS estimated using standard measurement in the far field.

  8. Grouting guidelines for Hanford Tanks Initiative cone penetrometer borings

    International Nuclear Information System (INIS)

    Iwatate, D.F.

    1998-01-01

    Grouting of an open cone penetrometer (CP) borehole is done to construct a barrier that prevents the vertical migration of fluids and contaminants between geologic units and aquifers intersected by the boring. Whether to grout, the types of grout, and the method of deployment are functions of the site-specific conditions. This report recommends the strategy that should be followed both before and during HTI [Hanford Tanks Initiative] CP deployment to decide specific borehole grouting needs at Hanford SST farms. Topics discussed in this report that bear on this strategy include: Regulatory guidance, hydrogeologic conditions, operational factors, specific CP grouting deployment recommendations

  9. Evaluation of the tear film stability after laser in situ keratomileusis using the tear film stability analysis system.

    Science.gov (United States)

    Goto, Tomoko; Zheng, Xiaodong; Klyce, Stephen D; Kataoka, Hisashi; Uno, Toshihiko; Yamaguchi, Masahiko; Karon, Mike; Hirano, Sumie; Okamoto, Shigeki; Ohashi, Yuichi

    2004-01-01

    To evaluate the tear film stability of patients before and after laser in situ keratomileusis (LASIK) using the tear film stability analysis system (TSAS). Prospective observational case series. New videokeratography software for a topographic modeling system (TMS-2N) was developed that can automatically capture consecutive corneal surface images every second for 10 seconds. Thirty-four subjects (64 eyes) who underwent myopia LASIK were enrolled in this study. All subjects were examined with the new system before LASIK and at 1 week, 1 month, 3 months, and 6 months after the surgery. Corneal topographs were analyzed for tear breakup time (TMS breakup time) and breakup area (TMS breakup area). Based on pre-LASIK TSAS analysis, subjects were separated into normal and abnormal TSAS value groups. The criteria for the normal group were either TMS breakup time more than 5 seconds or TMS breakup area less than 0.2. The percentage of the occurrence of superficial punctuate keratitis was compared between the two groups with regard to subject's dry eye signs and symptoms. Tear film stability decreased significantly during the early period after LASIK, as indexed by decreased TMS breakup time and increased TMS breakup area. Tear film instability resolved at 6 months after surgery. Before LASIK, 22 subjects (43 eyes) had normal TSAS evaluation and 12 subjects (21 eyes) were abnormal. After LASIK, among normal TSAS value eyes, 8 of 43 (18.6%) eyes developed superficial punctuate keratitis. In sharp contrast, 14 of 21 (66.7%) eyes in the abnormal group displayed superficial punctuate keratitis, correlating well with the patients' dry eye symptoms. The difference in the presence of superficial punctuate keratitis after LASIK between normal and abnormal TSAS value groups was statistically significant (P <.001). Subjects with abnormal TSAS evaluation also displayed resistance to dry eye treatment and had extended period of recovery. Tear film stability analysis can be a useful

  10. Disposal of radioactive grouts into hydraulically fractured shale

    International Nuclear Information System (INIS)

    1983-01-01

    A process for permanent waste disposal has been in operation for nearly 20 years at Oak Ridge National Laboratory (ORNL). In this method, intermediate-level radioactive waste effluents in the form of a slurry containing hydraulic binders (grouts) are injected by means of fracturing into a deep underground formation (a nearly impervious shale formation) considered to be isolated from the surface. The composition of the grout is carefully chosen so that the slurry thus injected solidifies in situ, ensuring fixation of the waste and rendering this type of disposal final in character. This process - ''hydrofracture'' or ''shale fracturing'' - immobilizes the wastes directly in situ, in such a condition that is well removed from the biosphere. It is an inexpensive process that is particularly suited for the permanent disposal of large batches of certain types of wastes under specific conditions. Some sections of this report are concerned with the general aspects of the hydrofracture process. Other sections are site specific and discuss the development of the process at ORNL and the operating experience with the ORNL facility. Sections 2 and 3 are concerned with the general aspects of site selection and are not site specific. Sections 4, 5, 6 and 8 are concerned with operating experience at ORNL and are site specific. Section 7 (safety assessment) is based on ORNL experience, but the considerations that are discussed in this section have general application. Details of the operating experience with the process at ORNL and West Valley are given in Appendix 1. Appendix 2 is a brief treatment of the theory of fracture mechanics

  11. Grout Treatment Facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1992-07-01

    The Grout Treatment Facility (GTF) is an existing treatment, storage, and/or disposal (TSD) unit located in the 200 East Area and the adjacent 600 Area of the Hanford Site. The GTF mixes dry cementitious solids with liquid mixed waste (containing both dangerous and radioactive constituents) produced by Hanford Site operations. The GTF consists of the following: The 241-AP-02D and 241-AP-04D waste pump pits and transfer piping; Dry Materials Facility (DMF); Grout Disposal Facility (GDF), consisting of the disposal vault and support and monitoring equipment; and Grout Processing Facility (GPF) and Westinghouse Hanford Company on the draft Hanford Facility Dangerous Waste Permit and may not be read to conflict with those comments. The Grout Treatment Facility Dangerous Waste Permit Application consists of both a Part A and a Part B permit application. An explanation of the Part A revisions associated with this TSD unit, including the current revision, is provided at the beginning of the Part A section. The Part B consists of 15 chapters addressing the organization and content of the Part B checklist prepared by the Washington State Department of Ecology (Ecology 1987). For ease of reference, the checklist section numbers, in brackets, follow chapter headings and subheadings

  12. Grouting of karstic arch dam foundation

    Energy Technology Data Exchange (ETDEWEB)

    Young, J.; Rigbey, S. [Acres International, Niagara Falls, ON (Canada)

    2002-07-01

    A 200 m high arch dam and a 2000 MW underground power house complex is under development in the Middle East. The project is located in a highly seismic area in rugged, mountainous terrain. The arch dam is constructed on good quality limestone and dolomitic limestone rock mass, but it contains several zones of disturbed or sheared rock. The basement rock is slightly karstic with hydraulic conductivities in the order of 100 Lugeons. In order to get a satisfactory foundation surface for the dam, it will be necessary to excavate extensively and backfill with concrete. Because of the presence of many clay infilled cavities and fractures, geotechnicians are considering the installation of a multiple row grout curtain to a depth of 150 m below the dam foundation to ensure adequate seepage and uplift parameters when the reservoir is impounded. Initial grouting water pressure test results suggested that the grouting and drainage curtain should be extended to the left abutment beyond the current design. However, when horizontal slide models of the dam abutment were developed using the finite element program SEEPW, it was shown that there is no benefit to extending the length of grout curtains unless they are tied to an area of much lower hydraulic conductivity much deeper in the abutment. 1 tab., 5 figs.

  13. Crack Formation in Grouted Annular Composite

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The objective of the present analysis is to identify the reason for extensive crack formation which occurred during an annulus grouting performance test, to evaluate possible consequences of the cracking, and to recommend measures to be taken in order to avoid similar problems in the future....

  14. Stability investigations of zinc and cobalt precipitates immobilized by in situ bioprecipitation (ISBP) process

    KAUST Repository

    Satyawali, Yamini; Schols, Edo; Van Roy, Sandra; Dejonghe, Winnie; Diels, Ludo; Vanbroekhoven, Karolien

    2010-01-01

    In situ bioprecipitation (ISBP), which involves immobilizing the metals as precipitates (mainly sulphides) in the solid phase, is an effective method of metal removal from contaminated groundwater. This study investigated the stability of metal precipitates formed after ISBP in two different solid-liquid matrices (artificial and natural). The artificial matrix consisted of sand, Zn (200mgL-1), artificial groundwater and a carbon source (electron donor). Here the stability of the Zn precipitates was evaluated by manipulation of redox and pH. The natural system matrices included aquifer material and groundwater samples collected from three different metal (Zn and Co) contaminated sites and different carbon sources were provided as electron donors. In the natural matrices, metal precipitates stability was assessed by changing aquifer redox conditions, sequential extraction, and BIOMET® assay. The results indicated that, in the artificial matrix, redox manipulation did not impact the Zn precipitates. However the sequential pH change proved detrimental, releasing 58% of the precipitated Zn back into liquid phase. In natural matrices, the applied carbon source largely affected the stability of metal precipitates. Elemental analysis performed on the precipitates formed in natural matrix showed that the main elements of the precipitates were sulphur with Zn and Co. © 2010 Elsevier B.V.

  15. Ultra-Small Fatty Acid-Stabilized Magnetite Nanocolloids Synthesized by In Situ Hydrolytic Precipitation

    Directory of Open Access Journals (Sweden)

    Kheireddine El-Boubbou

    2015-01-01

    Full Text Available Simple, fast, large-scale, and cost-effective preparation of uniform controlled magnetic nanoparticles remains a major hurdle on the way towards magnetically targeted applications at realistic technical conditions. Herein, we present a unique one-pot approach that relies on simple basic hydrolytic in situ coprecipitation of inexpensive metal salts (Fe2+ and Fe3+ compartmentalized by stabilizing fatty acids and aided by the presence of alkylamines. The synthesis was performed at relatively low temperatures (~80°C without the use of high-boiling point solvents and elevated temperatures. This method allowed for the production of ultra-small, colloidal, and hydrophobically stabilized magnetite metal oxide nanoparticles readily dispersed in organic solvents. The results reveal that the obtained magnetite nanoparticles exhibit narrow size distributions, good monodispersities, high saturation magnetizations, and excellent colloidal stabilities. When the [fatty acid] : [Fe] ratio was varied, control over nanoparticle diameters within the range of 2–10 nm was achieved. The amount of fatty acid and alkylamine used during the reaction proved critical in governing morphology, dispersity, uniformity, and colloidal stability. Upon exchange with water-soluble polymers, the ultra-small sized particles become biologically relevant, with great promise for theranostic applications as imaging and magnetically targeted delivery vehicles.

  16. Stability investigations of zinc and cobalt precipitates immobilized by in situ bioprecipitation (ISBP) process

    KAUST Repository

    Satyawali, Yamini

    2010-09-01

    In situ bioprecipitation (ISBP), which involves immobilizing the metals as precipitates (mainly sulphides) in the solid phase, is an effective method of metal removal from contaminated groundwater. This study investigated the stability of metal precipitates formed after ISBP in two different solid-liquid matrices (artificial and natural). The artificial matrix consisted of sand, Zn (200mgL-1), artificial groundwater and a carbon source (electron donor). Here the stability of the Zn precipitates was evaluated by manipulation of redox and pH. The natural system matrices included aquifer material and groundwater samples collected from three different metal (Zn and Co) contaminated sites and different carbon sources were provided as electron donors. In the natural matrices, metal precipitates stability was assessed by changing aquifer redox conditions, sequential extraction, and BIOMET® assay. The results indicated that, in the artificial matrix, redox manipulation did not impact the Zn precipitates. However the sequential pH change proved detrimental, releasing 58% of the precipitated Zn back into liquid phase. In natural matrices, the applied carbon source largely affected the stability of metal precipitates. Elemental analysis performed on the precipitates formed in natural matrix showed that the main elements of the precipitates were sulphur with Zn and Co. © 2010 Elsevier B.V.

  17. Durability 2007. Injection grout investigations. Background description

    International Nuclear Information System (INIS)

    Orantie, K.; Kuosa, H.

    2008-12-01

    The aim of this project was to evaluate the durability risks of injection grouts. The investigations were done with respect to the application conditions, materials and service life requirements at the ONKALO underground research facility. The study encompassed injection grout mixtures made of ultrafine cement with and without silica fume. Some of the mixtures hade a low pH and thus a high silica fume content. The project includes a background description on durability literature, laboratory testing programme, detailed analysis of results and recommendations for selecting of ideal grout mixtures. The background description was made for the experimental study of low-pH and reference rock injection grouts as regards pore- and microstructure, strength, shrinkage/swelling and thus versatile durability properties. A summary of test methods is presented as well as examples, i.e. literature information or former test results, of expected range of results from the tests. Also background information about how the test results correlate to other material properties and mix designs is presented. Besides the report provides basic information on the pore structure of cement based materials. Also the correlation between the pore structure of cement based materials and permeability is shortly discussed. The test methods included in the background description are compressive strength, measurement of bulk drying, autogenous and chemical shrinkage and swelling, hydraulic conductivity / permeability, capillary water uptake test, mercury intrusion porosimetry (MIP) and thin section analysis. Three main mixtures with water-binder ratio of 0.8, 1.0 and 1.4 and silica fume content of 0, 15 and 40% were studied in the laboratory. Besides two extra mixtures were studied to provide additional information about the effect of varying water-dry-material ratio and silica fume content on durability. The evaluation of water tightness based on water permeability coefficient and micro cracking was

  18. Quantitative modelling of the degradation processes of cement grout. Project CEMMOD

    Energy Technology Data Exchange (ETDEWEB)

    Grandia, Fidel; Galindez, Juan-Manuel; Arcos, David; Molinero, Jorge (Amphos21 Consulting S.L., Barcelona (Spain))

    2010-05-15

    Grout cement is planned to be used in the sealing of water-conducting fractures in the deep geological storage of spent nuclear fuel waste. The integrity of such cementitious materials should be ensured in a time framework of decades to a hundred of years as mimum. However, their durability must be quantified since grout degradation may jeopardize the stability of other components in the repository due to the potential release of hyperalkaline plumes. The model prediction of the cement alteration has been challenging in the last years mainly due to the difficulty to reproduce the progressive change in composition of the Calcium-Silicate-Hydrate (CSH) compounds as the alteration proceeds. In general, the data obtained from laboratory experiments show a rather similar dependence between the pH of pore water and the Ca-Si ratio of the CSH phases. The Ca-Si ratio decreases as the CSH is progressively replaced by Si-enriched phases. An elegant and reasonable approach is the use of solid solution models even keeping in mind that CSH phases are not crystalline solids but gels. An additional obstacle is the uncertainty in the initial composition of the grout to be considered in the calculations because only the recipe of low-pH clinker is commonly provided by the manufacturer. The hydration process leads to the formation of new phases and, importantly, creates porosity. A number of solid solution models have been reported in literature. Most of them assumed a strong non-ideal binary solid solution series to account for the observed changes in the Ca-Si ratios in CSH. However, it results very difficult to reproduce the degradation of the CSH in the whole Ca-Si range of compositions (commonly Ca/Si=0.5-2.5) by considering only two end-members and fixed nonideality parameters. Models with multiple non-ideal end-members with interaction parameters as a function of the solid composition can solve the problem but these can not be managed in the existing codes of reactive

  19. Degree of saturation effect on the grout-soil interface shear strength of soil nailing

    Directory of Open Access Journals (Sweden)

    Wang Qiong

    2016-01-01

    Full Text Available In the grouted soil nailing system, the bonding strength of cement grout-soil interface offers the required resistance to maintain the stability of whole structure. In practice, soil nailing applications are often placed at unsaturated conditions, such as soil slopes, shallow foundations, retaining walls and pavement structures. In these cases, the water content in the soil nail zone may increase or decrease due to rain water or dry weather, and even cannot become saturated during their design service life. In this study, the effect of water content (degree of saturation on the shear strength of interface between cement grout and sand are experimentally investigated by means of direct shear test. Meanwhile the water retention curve was determined and interface microstructure was observed. Experimental results show that the shear strength of interface changes non-monotonously with degree of saturation when the interface was prepared, due to the non-monotonousness of the cohesiveness between soil particles. The less the cohesiveness between sand particles, the more grout was observed been penetrated into the voids, and thus the larger the interface shear stress.

  20. Theoretical investigations of grout seal longevity - Final report

    International Nuclear Information System (INIS)

    Alcorn, S.; Coons, W.; Christian-Frear, T.; Wallace, M.

    1992-04-01

    Theoretical investigations into the longevity of repository seals have dealt primarily with the development of a methodology to evaluate interactions between portland cement-based grout and groundwater. Evaluation of chemical thermodynamic equilibria between grout and groundwater, and among grout, groundwater, and granitic host rock phases using the geochemical codes EQ3NR/EQ6 suggests that a fracture filled with grout and saturated with groundwater will tend to fill and 'tighten' with time. Results of these investigations suggest that cement grout seals will maintain an acceptable level of performance for tens of thousands to millions of years, provided the repository is sited where groundwater chemistry is compatible with the seals and hydrologic gradients are low. The results of the grout: groundwater: rock calculations suggest that buffering of the fracture seals chemical systems by the granite rock may be important in determining the long-term fate of grout seals and the resulting phase assemblage in the fracture. The similarity of the modelled reaction products to those observed in naturally filled fractures suggests that with time equilibrium will be approached and grouted fractures subject to low hydrologic gradients will continue to seal. If grout injected into fractures materially reduces groundwater flux, the approach to chemical equilibrium will likely be accelerated. In light of this, even very thin or imperfectly grouted fractures would tighten in suitable hydrogeologic environments. (29 refs.) (au)

  1. Feasibility of permeation grouting for constructing subsurface barriers

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1994-04-01

    Efforts are being made to devise technologies that provide interim containment of waste sites while final remediation alternatives are developed. Permeation grouting, a technique used extensively in the civil and mining engineering industry has been investigated as a method for emplacing a subsurface containment barrier beneath existing waste sites. Conceptually an underlying barrier is placed by injecting grout into the formation at less than fracturing pressure from a series of directionally drilled boreholes beneath the waste site. This study evaluated the penetration and performance characteristics in varying soil conditions of four different grout materials (two microfine cements, mineral wax, and sodium silicate) at a field scale. Field testing consisted of grout injection via sleeve (tube-a'-manchette) pipe into both vertical and horizontal borehole configurations at the Mixed Waste Landfill Integrated Demonstration site at Sandia National Laboratories. Prior to, during, and after grout injection non-intrusive geophysical techniques were used to map grout flow. Following the tests, the site was excavated to reveal details of the grout permeation, and grouted soil samples were cored for laboratory characterization. The non-intrusive and intrusive grout mapping showed preferential flow patterns, i.e., the grout tended to follow the path of least resistance. Preliminary testing indicates that permeation grouting is a feasible method for emplacing a low permeability subsurface barrier in the semi-arid unconsolidated alluvial soils common to the Southwest. Despite the success of this project, difficulties in predicting grout flow in heterogeneous soils and non-intrusive methods for imaging grout location and continuity are issues that need more attention

  2. Casestudy of stabilization of structural-unstable soilsusing grouting ОПЫТ ЗАКРЕПЛЕНИЯ СТРУКТУРНО-НЕУСТОЙЧИВЫХ ГРУНТОВ ЦЕМЕНТАЦИЕЙ

    Directory of Open Access Journals (Sweden)

    Golovanov Aleksandr Mikhailovich

    2013-08-01

    Full Text Available More than 20 years ago, Rostov-based Promstroyniiproekt Institute (Research and Development Institute for Industrial Engineering, backed by Geotechnika group of companies and other organizations, commenced using cement grouting to stabilize soil as part of foundation soils of buildings. It has turned out that consolidation of water saturated by clay accelerates grouting and assures higher strength than the silicification method. The article describes a new method of grouting and a case study of grouting stabilization of the foundation soil of a five-storey residential house, made by subsiding soils and subjacent fluid-plastic clay loams.The work was complicated by the fact that clay was displaced by the cement-sand mortar injected at the pressure insufficient for formation of discontinuous cavities. In these circumstances, the team of researchers developed and implemented an integrated solution to avoid clay clustering under the influence of the injected grout.The authors consider problems arising in the course of operation of buildings in the above geotechnical environment and describe the sequence of grouting operations. The article includes the work performance pattern and patterns of building control.Описан новый комплексный способ цементации грунтов и опыт его применения для усиления основания существующего пятиэтажного жилого дома, сложенного просадочными грунтами, подстилаемыми текучепластичными суглинками. Рассмотрены некоторые проблемы, возникающие при эксплуатации зданий в данных инженерно-геологических условиях, и описана последовательность работ при цементации.

  3. Grouts and concretes for the Waste Isolation Pilot Project (WIPP)

    International Nuclear Information System (INIS)

    Wakeley, L.D.

    1990-01-01

    The Structures Laboratory of the U.S. Army Engineer Waterways Experiment Station has conducted research on cement-based composites for the Waste Isolation Pilot Project (WIPP) since 1977, in cooperation with Sandia National Laboratories. Field testing requirements guided initial development of grouts. Concurrent and later laboratory studies explored the chemical stability and probable durability of these mixtures. Beginning in 1985, a series of small-scale seal performance tests at the WIPP prompted development of an expansive salt-saturated concrete. Important lessons learned from this ongoing work include: (1) carefully tailored mixtures can tolerate phase changes involving Ca, Al, and SO 4 , without loss of structural integrity; (2) handling and placement properties are probably more crucial to the mixtures than is exact phase composition; and (3) for the environment of a geologic repository, demonstrated chemical durability will be the best indicator of long-term performance

  4. Stability of silver nanoparticle monolayers determined by in situ streaming potential measurements

    International Nuclear Information System (INIS)

    Morga, Maria; Adamczyk, Zbigniew; Oćwieja, Magdalena

    2013-01-01

    A silver particle suspension obtained by a chemical reduction was used in this work. Monolayers of these particles (average size 28 nm) on mica modified by poly(allylamine hydrochloride) were produced under diffusion-controlled transport. Monolayer coverages, quantitatively determined by atomic force microscopy (AFM) and SEM, was regulated by adjusting the nanoparticle deposition time and the suspension concentration. The zeta potential of the monolayers was determined by streaming potential measurements carried out under in situ (wet) conditions. These measurements performed for various ionic strengths and pH were interpreted in terms of the three-dimensional (3D) electrokinetic model. The stability of silver monolayers was also investigated using streaming potential and the AFM methods. The decrease in the surface coverage of particles as a function of time and ionic strength varied between 10 −1 and 10 −4  M was investigated. This allowed one to determine the equilibrium adsorption constant K a and the binding energy of silver particles (energy minima depth). Energy minima depth were calculated that varied between −18 kT for I = 10 −1  M and −19 kT for I = 10 −4 for pH 5.5 and T = 298 K. Our investigations suggest that the interactions between surface and nanoparticles are controlled by the electrostatic interactions among ion pairs. It was also shown that the in situ electrokinetic measurements are in accordance with those obtained by more tedious ex situ AFM measurements. This confirmed the utility of the streaming potential method for direct kinetic studies of nanoparticle deposition/release processes.Graphical Abstract

  5. Soil surface stabilization using an in situ plutonium coating techniuqe at the Nevada Test Site

    International Nuclear Information System (INIS)

    Lew, J.; Snipes, R.; Tamura, T.

    1996-01-01

    The Hazardous Waste Remedial Actions Program (HAZWRAP), in collaboration with the University of Nevada at Reno (UNR), has developed and is investigating an in situ plutonium treatment for soils at the Nevada Test Site (NTS). The concept, conceived by Dr. T. Tamura and refined at HAZWRAP, was developed during the Nevada Applied Ecology Program investigation. In analyzing for plutonium in soils, it was noted that the alpha emanation of plutonium was greatly attenuated if traces of iron or manganese oxides were present in the final electroplating stage. The technique would reduce resuspension of alpha particles into the air by coating the contaminants in soils in situ with an environmentally compatible, durable, and nontoxic material. The coating materials (calcium hydroxide, ferrous sulfate) reduce resuspension by providing a cementitious barrier against radiation penetration while retaining soil porosity. This technique not only stabilizes plutonium-contaminated soils, but also provides an additional protection from worker exposure to radiation during remediation activities. Additionally, the coating would decrease the water solubility of the contaminant and, thus, reduce its migration through soil and uptake by plants

  6. Stability of added and in situ-produced vitamin B12 in breadmaking.

    Science.gov (United States)

    Edelmann, Minnamari; Chamlagain, Bhawani; Santin, Marco; Kariluoto, Susanna; Piironen, Vieno

    2016-08-01

    Vitamin B12 exists naturally in foods of animal origin and is synthesised only by certain bacteria. New food sources are needed to ensure vitamin B12 intake in risk groups. This study aimed to investigate the stability of added cyanocobalamin (CNCbl, chemically modified form) and hydroxocobalamin (OHCbl, natural form) and in situ-synthesised vitamin B12 in breadmaking. Samples were analysed both with a microbiological (MBA) and a liquid chromatographic (UHPLC) method to test applicability of these two methods. Proofing did not affect CNCbl and OHCbl levels. By contrast, 21% and 31% of OHCbl was lost in oven-baking steps in straight- and sponge-dough processes, respectively, whereas CNCbl remained almost stable. In sourdough baking, 23% of CNCbl and 44% of OHCbl were lost. In situ-produced vitamin B12 was almost as stable as added CNCbl and more stable than OHCbl. The UHPLC method showed its superiority to the MBA in determining the active vitamin B12. Copyright © 2016. Published by Elsevier Ltd.

  7. Colloidal silica-grouting in demonstration tunnel 2 in ONKALO

    International Nuclear Information System (INIS)

    Hollmen, K.; Sievaenen, U.; Funehag, J.; Granberg, N.; Lyytinen, T.; Syrjaenen, P.

    2013-12-01

    Posiva carried out grouting using colloidal silica as the grouting material and with the time stop method as the design approach.Three fans were pre-grouted at Posiva Oy's research space ONKALO demonstration tunnel 2 in autumn 2011 and early winter 2012. Colloidal silica is a mix of one-component colloidal silica and accelerator. Before gelling, colloidal silica behaves like a Newtonian liquid. Colloidal silica's efficiency of penetrating hydraulic apertures in small fractures in rock is significantly better than that of cement-based grout. The grouting design was based on an analytical calculation model. A new technique was used in the grouting implementation, which primarily differed from the previous technique in regard to vacuum pumping and packers. The goal of the first grouting fan in the demonstration tunnel was to check the functionality of the equipment and the method; therefore, the fan was drilled into rock mass with no hydraulic conducting fractures. The second grouting fan was drilled into rock mass with an observed fairly low hydraulic conductivity that was lower than the start criterion established in Posiva Oy's requirements to manage groundwater inflows. Nevertheless, the grouting was carried out. The sealing effect was estimated from the control holes, and a slight improvement in sealing was noted. The holes of the third grouting fan clearly penetrated a water conductive rock mass. The grouting was carried out in two phases, in which the new holes in the second phase were drilled between the existing ones that were drilled in the first phase. In the third fan, the grouting holes of the first phase were noted to be significantly crooked and the second phase grouting holes were drilled in locations that differed from the original design. The quantity of grouting holes was increased in the second phase. The sealing effect was estimated by monitoring the second phase holes and control holes. Based on observations from the control holes

  8. Shape-and size-controlled Ag nanoparticles stabilized by in situ generated secondary amines

    Energy Technology Data Exchange (ETDEWEB)

    Ramírez-Meneses, E., E-mail: esther.ramirez@ibero.mx [Departamento de Ingeniería y Ciencias Químicas, Universidad Iberoamericana, Prolongación Paseo de la Reforma 880, Lomas de Santa Fe, Distrito Federal C.P. 01219 (Mexico); Montiel-Palma, V. [Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001 Col. Chamilpa, Cuernavaca, Morelos C.P. 62209 (Mexico); Domínguez-Crespo, M.A.; Izaguirre-López, M.G. [Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada-IPN, Unidad Altamira. Km 14.5 Carretera Tampico-Puerto Industrial, 89600 Altamira, Tamaulipas (Mexico); Palacios-Gonzalez, E. [Laboratorio de Microscopia de Ultra alta Resolución, Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas No. 152, C.P. 07730 México D.F. (Mexico); Dorantes-Rosales, H. [Departamento de Metalurgia, E.S.I.Q.I.E.-I.P.N., Unidad Profesional Adolfo López Mateos, Zacatenco, Delegación. Gustavo A. Madero, C.P. 07738 México D.F. (Mexico)

    2015-09-15

    Highlights: • Ag nanoparticles were generated from Ag amido complexes AgN{sup i}Pr{sub 2} and AgN(SiMe{sub 3}){sub 2}. • Ag nanoparticles were stabilized by in situ generated HN{sup i}Pr{sub 2} or HN(SiMe{sub 3}){sub 2}. • 1 or 5 equiv. of ethylenediamine as additional capping agent decreases the average size of the particles. • Ethylenediamine favor the formation of spherical particles. - Abstract: Silver amides such as AgN{sup i}Pr{sub 2} and AgN(SiMe{sub 3}){sub 2} have been employed successfully as precursors for the yield synthesis of silver nanoparticles under mild conditions of dihydrogen gas reduction (2 atm) in organic media. Transmission electron microscopy (TEM) showed the formation of silver nanoparticles with FCC structure, variously sized from 26 to 35 nm for AgN{sup i}Pr{sub 2} and from 14 to 86 nm for AgN(SiMe{sub 3}){sub 2}, the synthesis could take place in absence of added stabilizers due to the in situ formation of secondary amines from the reaction of dihydrogen gas with the amide ligands of the silver precursor. Indeed, the presence of HNR{sub 2} (R = iPr{sub 2}, N(SiMe{sub 3}){sub 2}) on the surface of the nanoparticle was confirmed by spectroscopic means. Finally, the addition of ethylenediamine as additional capping agent allowed not only the control of the structural characteristics of the resulting Ag nanoparticles (well-dispersed with spherical shape), but that regarding the nanoparticle size as it inhibited overgrowth, limiting it to ca. 25 nm.

  9. In situ crosslinking of surface-initiated ring opening metathesis polymerization of polynorbornene for improved stability.

    Science.gov (United States)

    Fursule, Ishan A; Abtahi, Ashkan; Watkins, Charles B; Graham, Kenneth R; Berron, Brad J

    2018-01-15

    In situ crosslinking is expected to increase the solvent stability of coatings formed by surface-initiated ring opening metathesis polymerization (SI ROMP). Solvent-associated degradation limits the utility of SI ROMP coatings. SI ROMP coatings have a unique capacity for post-functionalization through reaction of the unsaturated site on the polymer backbone. Any post-reaction scheme which requires a liquid solvent has the potential to degrade the coating and lower the thickness of the resulting film. We designed a macromolecular crosslinking group based on PEG dinorbornene. The PEG length is tailored to the expected mean chain to chain distance during surface-initiated polymerization. This crosslinking macromer is randomly copolymerized with norbornene through SI ROMP on a gold coated substrate. The solvent stability of polynorbornene coatings with and without PEG dinorbornene is quantitatively determined, and the mechanism of degradation is further supported through XPS and AFM analyses. The addition of the 0.25mol% PEG dinorbornene significantly increases the solvent stability of the SI ROMP coatings. The crosslinker presence in the more stable films is supported with observable PEG absorbances by FTIR and an increase in contact angle hysteresis when compared to non-crosslinked coatings. The oxidation of the SI ROMP coatings is supported by the observation of carbonyl oxygen in the polynorbornene coatings. The rapid loss of the non-crosslinked SI ROMP coating corresponds to nanoscale pitting across the surface and micron-scale regions of widespread film loss. The crosslinked coatings have uniform nanoscale pitting, but the crosslinked films show no evidence of micron-scale film damage. In all, the incorporation of minimal crosslinking content is a simple strategy for improving the solvent stability of SI ROMP coatings. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. 77 FR 69508 - Inservice Inspection of Prestressed Concrete Containment Structures With Grouted Tendons

    Science.gov (United States)

    2012-11-19

    ... Containment Structures With Grouted Tendons AGENCY: Nuclear Regulatory Commission. ACTION: Regulatory guide... (RG) 1.90, ``Inservice Inspection of Prestressed Concrete Containment Structures with Grouted Tendons... appropriate surveillance program for prestressed concrete containment structures with grouted tendons...

  11. Modeling Analysis For Grout Hopper Waste Tank

    International Nuclear Information System (INIS)

    Lee, S.

    2012-01-01

    The Saltstone facility at Savannah River Site (SRS) has a grout hopper tank to provide agitator stirring of the Saltstone feed materials. The tank has about 300 gallon capacity to provide a larger working volume for the grout nuclear waste slurry to be held in case of a process upset, and it is equipped with a mechanical agitator, which is intended to keep the grout in motion and agitated so that it won't start to set up. The primary objective of the work was to evaluate the flow performance for mechanical agitators to prevent vortex pull-through for an adequate stirring of the feed materials and to estimate an agitator speed which provides acceptable flow performance with a 45 o pitched four-blade agitator. In addition, the power consumption required for the agitator operation was estimated. The modeling calculations were performed by taking two steps of the Computational Fluid Dynamics (CFD) modeling approach. As a first step, a simple single-stage agitator model with 45 o pitched propeller blades was developed for the initial scoping analysis of the flow pattern behaviors for a range of different operating conditions. Based on the initial phase-1 results, the phase-2 model with a two-stage agitator was developed for the final performance evaluations. A series of sensitivity calculations for different designs of agitators and operating conditions have been performed to investigate the impact of key parameters on the grout hydraulic performance in a 300-gallon hopper tank. For the analysis, viscous shear was modeled by using the Bingham plastic approximation. Steady state analyses with a two-equation turbulence model were performed. All analyses were based on three-dimensional results. Recommended operational guidance was developed by using the basic concept that local shear rate profiles and flow patterns can be used as a measure of hydraulic performance and spatial stirring. Flow patterns were estimated by a Lagrangian integration technique along the flow paths

  12. Cement-latex grouting mortar for cementing boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Kateev, I S; Golyshkina, L A; Gorbunova, I V; Kurochkin, B M; Vakula, Ya V

    1980-01-01

    The need for the development of cement-latex grouting mortar for the purpose of separating strata when reinforcing boreholes at deposits in the Tatar Associated SSR is evaluated. Results of studies of the physical and mechanical properties of cement-latex grouting mortar systems (mortar plus brick) are presented. Formulas for preparing cement-latex grouting mortor are evaluated and results of industrial tests of such mortars shown.

  13. Tensile capacity of loop connections grouted with concrete or mortar

    DEFF Research Database (Denmark)

    Sørensen, Jesper Harrild; Hoang, Linh Cao; Olesen, John Forbes

    2017-01-01

    This paper presents a study of grout failure in symmetric U-bar loop connections loaded in tension, with focus on the performance of two grouting materials – concrete and mortar. The study contains an experimental investigation as well as a rigid-plastic modelling of the tensile capacity. The test...... to allow yielding of the U-bars. The experimental work showed that connections grouted with concrete performed better than the connections grouted with mortar. In the theoretical models, the difference in tested capacity is explained by the difference in the internal angle of friction and in the softening...... behaviour of concrete as compared with mortar....

  14. Powder metallurgical nanostructured medium carbon bainitic steel: Kinetics, structure, and in situ thermal stability studies

    Energy Technology Data Exchange (ETDEWEB)

    Lonardelli, I., E-mail: il244@cam.ac.uk [University of Cambridge, Materials Science and Metallurgy, Pembroke Street, Cambridge CB2 3QZ (United Kingdom); University of Trento, Materials Engineering and Industrial Technologies, via Mesiano 77, 38123 Trento (Italy); Bortolotti, M. [Fondazione Bruno Kessler, via Sommarive 18, 38123 Trento (Italy); Beek, W. van [Swiss-Norwegian Beamlines, ESRF, BP 220, 38043 Grenoble Cedex (France); Girardini, L.; Zadra, M. [K4-Sint, via Dante 300, 38057 Pergine Valsugana (Italy); Bhadeshia, H.K.D.H. [University of Cambridge, Materials Science and Metallurgy, Pembroke Street, Cambridge CB2 3QZ (United Kingdom)

    2012-10-15

    It has been possible to produce incredibly fine plates of bainitic ferrite separated by a percolating network of retained austenite in a medium carbon steel produced by mechanical alloying followed by spark plasma sintering and isothermal heat treatment. This is because the sintering process limits the growth of the austenite grains to such an extent that the martensite-start temperature is suppressed in spite of the medium carbon concentration. Furthermore, the fine austenite grain size accelerates the bainite transformation, which can therefore be suppressed to low temperatures to obtain a nanostructure. Microscopy and in situ synchrotron X-ray diffraction were used to investigate the morphology and the thermal stability of the retained austenite during continuous heating. These latter experiments revealed a gradient of carbon concentration in the retained austenite and a reduced thermal stability in high carbon film-austenite. It was also possible to correlate the evolution of defect density and carbon depletion in both retained austenite and bainitic ferrite during tempering.

  15. In-situ stabilization of the Geiger (C and M Oil) Superfund Site

    International Nuclear Information System (INIS)

    Andromalos, K.B.; Ameel, M.E.

    1994-01-01

    The Geiger (C and M Oil) Superfund Site is the first US Army Corps of Engineers managed soil remediation project which utilized the in-situ stabilization/solidification technique to remediate the soil. This project involved the remediation of approximately 23,000 cubic yards of contaminated soil. Contaminants of concern included chromium, lead, PCB'S, toluene, benzene, and other organic compounds. Clean-up criteria for the stabilized material was equal to the National Primary Drinking Water Regulations, when tested using the TCLP leachate extraction method. Chromium, lead, and toluene were the main contaminants of concern, with TCLP clean-up goals of 150, 15 and 1,000 parts per billion (ppb), respectively. This National Priorities List (NPL) site is located near Charleston, SC and was an abandoned old waste oil facility that utilized unlined shallow trenches for the storage of waste oil. This paper summarizes the initial testing programs and the final production work at the site. Extensive testing was performed throughout all phases of the project. This testing was performed for the purpose of mix optimization, quality assurance, and verification testing. Specific parameters tested included: TCLP testing of organics, metals and PCBs, permeability testing, and unconfirmed compression strength

  16. Cost estimate of grouting the proposed test pits at Idaho National Engineering Laboratory using the ORNL-recommended grouts

    International Nuclear Information System (INIS)

    Spence, R.D.

    1987-08-01

    EG and G Idaho will construct three experimental pits to simulate the TRU waste trenches at Idaho National Engineering Laboratory (INEL). Two of these pits will be grouted and then one will be destructively examined as soon as the grout cures and the other will be monitored for 10 years. Oak Ridge National Laboratory (ORNL) is evaluating grouts and will recommend a grout to EG and G Idaho to reduce the permeability of the pit, fill the large voids, and encapsulate the waste. A previous ORNL report (ORNL/TM-9881) discusses the grouts evaluated and the grout recommended based on those evaluations. This report evaluates the economics of grouting the experimental pits. The cost of double grouting two of the EG and G Idaho design pits at the Idaho National Engineering Laboratory using lance injection was estimated to be $100,000. Jet grouting the same two pits was estimated to cost $85,000. Both should be tried as part of the test EG and G Idaho is conducting

  17. Field-scale permeation testing of jet-grouted buried waste sites

    International Nuclear Information System (INIS)

    Loomis, G.G.; Zdinak, A.P.

    1996-01-01

    The Idaho National Engineering Laboratory (INEL) conducted field-scale hydraulic conductivity testing of simulated buried waste sites with improved confinement. The improved confinement was achieved by jet grouting the buried waste, thus creating solid monoliths. The hydraulic conductivity of the monoliths was determined using both the packer technique and the falling head method. The testing was performed on simulated buried waste sites utilizing a variety of encapsulating grouts, including high-sulfate-resistant Portland cement, TECT, (a proprietary iron oxide cement) and molten paraffin. By creating monoliths using in-situ jet grouting of encapsulating materials, the waste is simultaneously protected from subsidence and contained against further migration of contaminants. At the INEL alone there is 56,000 m 3 of buried transuranic waste commingled with 170,000--224,000 m 3 of soil in shallow land burial. One of the options for this buried waste is to improve the confinement and leave it in place for final disposal. Knowledge of the hydraulic conductivity for these monoliths is important for decision-makers. The packer tests involved coring the monolith, sealing off positions within the core with inflatable packers, applying pressurized water to the matrix behind the seal, and observing the water flow rate. The falling head tests were performed in full-scale 3-m-diameter, 3-m-high field-scale permeameters. In these permeameters, both water inflow and outflow were measured and equated to a hydraulic conductivity

  18. PHYSICAL PROPERTY MEASUREMENTS OF LABORATORY PREPARED SALTSTONE GROUT

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E.; Cozzi, A.; Edwards, T.

    2014-05-05

    The Saltstone Production Facility (SPF) built two new Saltstone Disposal Units (SDU), SDU 3 and SDU 5, in 2013. The variable frequency drive (VFD) for the grout transfer hose pump tripped due to high current demand by the motor during the initial radioactive saltstone transfer to SDU 5B on 12/5/2013. This was not observed during clean cap processing on July 5, 2013 to SDU 3A, which is a slightly longer distance from the SPF than is SDU 5B. Saltstone Design Authority (SDA) is evaluating the grout pump performance and capabilities to transfer the grout processed in SPF to SDU 3/5. To assist in this evaluation, grout physical properties are required. At this time, there are no rheological data from the actual SPF so the properties of laboratory prepared samples using simulated salt solution or Tank 50 salt solution will be measured. The physical properties of grout prepared in the laboratory with de-ionized water (DI) and salt solutions were obtained at 0.60 and 0.59 water to premix (W/P) ratios, respectively. The yield stress of the DI grout was greater than any salt grout. The plastic viscosity of the DI grout was lower than all of the salt grouts (including salt grout with admixture). When these physical data were used to determine the pressure drop and fluid horsepower for steady state conditions, the salt grouts without admixture addition required a higher pressure drop and higher fluid horsepower to transport. When 0.00076 g Daratard 17/g premix was added, both the pressure drop and fluid horsepower were below that of the DI grout. Higher concentrations of Daratard 17 further reduced the pressure drop and fluid horsepower. The uncertainty in the single point Bingham Plastic parameters is + 4% of the reported values and is the bounding uncertainty. Two different mechanical agitator mixing protocols were followed for the simulant salt grout, one having a total mixing time of three minutes and the other having a time of 10 minutes. The Bingham Plastic parameters

  19. Quantitative modelling of the degradation processes of cement grout. Project CEMMOD

    International Nuclear Information System (INIS)

    Grandia, Fidel; Galindez, Juan-Manuel; Arcos, David; Molinero, Jorge

    2010-05-01

    Grout cement is planned to be used in the sealing of water-conducting fractures in the deep geological storage of spent nuclear fuel waste. The integrity of such cementitious materials should be ensured in a time framework of decades to a hundred of years as mimum. However, their durability must be quantified since grout degradation may jeopardize the stability of other components in the repository due to the potential release of hyperalkaline plumes. The model prediction of the cement alteration has been challenging in the last years mainly due to the difficulty to reproduce the progressive change in composition of the Calcium-Silicate-Hydrate (CSH) compounds as the alteration proceeds. In general, the data obtained from laboratory experiments show a rather similar dependence between the pH of pore water and the Ca-Si ratio of the CSH phases. The Ca-Si ratio decreases as the CSH is progressively replaced by Si-enriched phases. An elegant and reasonable approach is the use of solid solution models even keeping in mind that CSH phases are not crystalline solids but gels. An additional obstacle is the uncertainty in the initial composition of the grout to be considered in the calculations because only the recipe of low-pH clinker is commonly provided by the manufacturer. The hydration process leads to the formation of new phases and, importantly, creates porosity. A number of solid solution models have been reported in literature. Most of them assumed a strong non-ideal binary solid solution series to account for the observed changes in the Ca-Si ratios in CSH. However, it results very difficult to reproduce the degradation of the CSH in the whole Ca-Si range of compositions (commonly Ca/Si=0.5-2.5) by considering only two end-members and fixed nonideality parameters. Models with multiple non-ideal end-members with interaction parameters as a function of the solid composition can solve the problem but these can not be managed in the existing codes of reactive

  20. Laboratory Testing of Silica Sol Grout in Coal Measure Mudstones

    Directory of Open Access Journals (Sweden)

    Dongjiang Pan

    2016-11-01

    Full Text Available The effectiveness of silica sol grout on mudstones is reported in this paper. Using X-ray diffraction (XRD, the study investigates how the silica sol grout modifies mudstone mineralogy. Micropore sizes and mechanical properties of the mudstone before and after grouting with four different materials were determined with a surface area/porosity analyser and by uniaxial compression. Tests show that, after grouting, up to 50% of the mesopore volumes can be filled with grout, the dominant pore diameter decreases from 100 nm to 10 nm, and the sealing capacity is increased. Uniaxial compression tests of silica sol grouted samples shows that their elastic modulus is 21%–38% and their uniaxial compressive strength is 16%–54% of the non-grouted samples. Peak strain, however, is greater by 150%–270%. After grouting, the sample failure mode changes from brittle to ductile. This paper provides an experimental test of anti-seepage and strengthening properties of silica sol.

  1. Efficiency of Micro-fine Cement Grouting in Liquefiable Sand

    International Nuclear Information System (INIS)

    Mirjalili, Mojtaba; Mirdamadi, Alireza; Ahmadi, Alireza

    2008-01-01

    In the presence of strong ground motion, liquefaction hazards are likely to occur in saturated cohesion-less soils. The risk of liquefaction and subsequent deformation can be reduced by various ground improvement methods including the cement grouting technique. The grouting method was proposed for non-disruptive mitigation of liquefaction risk at developed sites susceptible to liquefaction. In this research, a large-scale experiment was developed for assessment of micro-fine cement grouting effect on strength behavior and liquefaction potential of loose sand. Loose sand samples treated with micro-fine grout in multidirectional experimental model, were tested under cyclic and monotonic triaxial loading to investigate the influence of micro-fine grout on the deformation properties and pore pressure response. The behavior of pure sand was compared with the behavior of sand grouted with a micro-fine cement grout. The test results were shown that cement grouting with low concentrations significantly decreased the liquefaction potential of loose sand and related ground deformation

  2. Mechanical response of shock conditioned HPNS-5 (R-1) grout

    International Nuclear Information System (INIS)

    Plannerer, H.N.

    1997-01-01

    HPNS-5 (R-1) grout is a portland cement formulated mix designed for use as a rigid containment plug in vertical boreholes at the Nevada Test Site. Coincident with field testing of this grout in 1991 and 1992 , two arums of the grout mix were collected and positioned in the by pass drift of the DISTANT ZENITH event to expose the grout to passage of a nuclear driven stress wave. The drums were later retrieved to determine the mechanical behavior of the shock conditioned grout. Sealed hollow tubes positioned within the grout-filled drums to detect ductile flow on passage of the stress wave were found partially to completely filled with HPNS-5 grout following the experiment. Static mechanical tests support the evidence for ductile flow and place the transition from brittle fracture failure to ductile behavior in the shock conditioned grout at a confining stress between ambient and 5 MPa (725 psi). Uniaxial and triaxial tests delineated a stress-strain field for interstice collapse that interposes between the mechanics of linear elastic deformation and dilatancy. Hydrostatic stress loading between 25 MPa (3.6 ksi) and 60 MPa (8.7 ksi) results in a significant change of permanent set from 1% to greater than 15% volume strain

  3. Evolution of technetium speciation in reducing grout

    Energy Technology Data Exchange (ETDEWEB)

    Lukens, Wayne W.; Bucher, Jerome J.; Shuh, David K.; Edelstein,Norman M.

    2003-11-24

    Cementitious waste forms (CWFs) are an important component of the strategy to immobilize high-level nuclear waste resulting from plutonium production by the U.S. Department of Energy (DOE). Technetium (99Tc) is an abundant fission product of particular concern in CWFs due to the high solubility and mobility of pertechnetate, TcO4-, the stable form of technetium in aerobic environments. CWFs can more effectively immobilize 99Tc if they contain additives that reduce mobile TcO4- to immobile Tc(IV) species. Leaching of 99Tc from reducing CWFs that contain Tc(IV) is much slower than for CWFs containing TcO4-. Previous X-ray absorption fine structure (XAFS) studies showed that the Tc(IV) species were oxidized to TcO4- in reducing grout samples prepared on a laboratory scale. Whether the oxidizer was atmospheric O2 or NO3- in the waste simulant was not determined. In actual CWFs, rapid oxidation of Tc(IV) by NO3- would be a concern, whereas oxidation by atmospheric O2 would be of less concern due to the slow diffusion and reaction of O2 with the reducing CWF. To address this uncertainty, two series of reducing grouts were prepared using TcO4- containing waste simulants with and without NO3-. In the first series of samples, the TcO4- was completely reduced using Na2S, and the samples were placed in containers that permitted O2 diffusion. In these samples, all of the technetium was initially present as aTc(IV) sulfide compound, TcSx, which was characterized using extended X-ray absorption fine structure (EXAFS) spectroscopy, and is likely Tc2S7. The TcSx initially present in the grout samples was steadily oxidized over 4 years. In the second series of samples, all of the TcO4- was not initially reduced, and the grout samples were placed in airtight containers. In these samples, the remaining TcO4- continued to be reduced as the samples aged, presumably due to the presence of reducing blast furnace slag. When samples in the second series were exposed to atmosphere, the

  4. Estimating emissions from grout pouring operations

    International Nuclear Information System (INIS)

    Ballinger, M.Y.; Hendrickson, D.W.

    1993-08-01

    Grouting is a method for disposal of low-level radioactive waste in which a contaminated solution is mixed into a slurry, poured into a large storage vault, then dried, fixing the contaminants within a stable solid matrix. A model (RELEASE) has been developed to estimate the quantity of aeorsol created during the pouring process. Information and equations derived from spill experiments were used in the model to determine release fractions. This paper discusses the derivation of the release fraction equation used in the code and the model used to account for gravity settling of particles in the vault. The input and results for a base case application are shown

  5. In situ stabilization of cadmium-, lead-, and zinc-contaminated soil using various amendments.

    Science.gov (United States)

    Lee, Sang-Hwan; Lee, Jin-Soo; Choi, Youn Jeong; Kim, Jeong-Gyu

    2009-11-01

    Chemical stabilization is an in situ remediation method that uses inexpensive amendments to reduce contaminant availability in polluted soil. We tested the effects of several amendments (limestone, red-mud, and furnace slag) on the extractability of heavy metals, microbial activities, phytoavailability of soil metals (assessed using lettuce, Lactuca sativa L.), and availability of heavy metals in ingested soil to the human gastrointestinal system (assessed using the physiologically based extraction test). The application of soil amendments significantly decreased the amount of soluble and extractable heavy metals in the soil (p<0.05). The decreased extractable metal content of soil was accompanied by increased microbial activity and decreased plant uptake of heavy metals. Soil microbial activities (soil respiration, urease, and dehydrogenase activity) significantly increased in limestone and red-mud-amended soils. Red-mud was the most effective treatment in decreasing heavy-metal concentrations in lettuce. Compared to non-amended control soil, lettuce uptake of Cd, Pb, and Zn was reduced 86%, 58%, and 73%, respectively, by the addition of red-mud.

  6. Nanocapsule of cationic liposomes obtained using "in situ" acrylic acid polymerization: stability, surface charge and biocompatibility.

    Science.gov (United States)

    Scarioti, Giovana Danieli; Lubambo, Adriana; Feitosa, Judith P A; Sierakowski, Maria Rita; Bresolin, Tania M B; de Freitas, Rilton Alves

    2011-10-15

    In this work, didecyldimethylammonium bromide (DDAB) and 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) (2.5:1) were used to prepare liposomes coated with polyacrylic acid (PAA) using "in situ" polymerization with 2.5, 5 and 25 mM of acrylic acid (AA). The PAA concentrations were chosen to achieve partially to fully covered capsules, and the polymerization reaction was observed with real-time monitoring using dynamic light scattering (NanoDLS). The DDAB:DOPE liposomes showed stability in the tested temperature range (25-70°C), whereas the results confirmed the success of the polymerization according to superficial charge (zeta potential of +66.7±1.2 mV) results and AFM images. For the liposomes that were fully coated with PAA (zeta potential of +0.3±3.9 mV), cytotoxicity was independent of the concentration of albumin. Cationic liposomes and nanocapsules of the stable liposomes coated with PAA were obtained by controlling the surface charge, which was the most important factor related to cytotoxicity. Thus, a potential, safe drug nanocarrier was successfully developed in this work. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Localized in situ polymerization on graphene surfaces for stabilized graphene dispersions.

    Science.gov (United States)

    Das, Sriya; Wajid, Ahmed S; Shelburne, John L; Liao, Yen-Chih; Green, Micah J

    2011-06-01

    We demonstrate a novel in situ polymerization technique to develop localized polymer coatings on the surface of dispersed pristine graphene sheets. Graphene sheets show great promise as strong, conductive fillers in polymer nanocomposites; however, difficulties in dispersion quality and interfacial strength between filler and matrix have been a persistent problem for graphene-based nanocomposites, particularly for pristine graphene. With this in mind, a physisorbed polymer layer is used to stabilize graphene sheets in solution. To create this protective layer, we formed an organic microenvironment around dispersed graphene sheets in surfactant solutions, and created a nylon 6, 10 or nylon 6, 6 coating via interfacial polymerization. Technique lies at the intersection of emulsion and admicellar polymerization; a similar technique was originally developed to protect luminescent properties of carbon nanotubes in solution. These coated graphene dispersions are aggregation-resistant and may be reversibly redispersed in water even after freeze-drying. The coated graphene holds promise for a number of applications, including multifunctional graphene-polymer nanocomposites. © 2011 American Chemical Society

  8. In situ vitrification demonstration for the stabilization of buried wastes at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Jacobs, G.K.; Spalding, B.P.; Carter, J.G.; Koegler, S.S.

    1987-01-01

    A demonstration of In Situ Vitrification (ISV) technology for the stabilization of radioactively contaminated soil sites at the Oak Ridge National Laboratory (ORNL) was successfully completed during July 1987. This demonstration is the first application of the ISV process not performed at the Hanford Site, where the technology was developed and patented by Pacific Northwest Laboratory (PNL). The joint ORNL-PNL pilot-scale demonstration was performed on a 3/8-scale trench (2 m deep x 1 m wide x 10 m long) that was constructed to simulate a typical seepage trench used for liquid low-level radioactive waste disposal at ORNL from 1951 to 1966. In the ISV process, electrodes are inserted around a volume of contaminated soil, power is applied to the electrodes, and the entire mass is melted from the surface of the soil down through the contaminated zone, thus making a glassy-to-microcrystalline waste form that incorporates the contaminants. Gases produced during the melting are collected, treated, monitored, and released through an off-gas process trailer. In the ORNL demonstration, a 25-t mass of melted rock approximately 1.2 m thick x 2.1 m wide x 4.9 m long was formed during 110 h of operation that consumed approximately 29 MWh of power. Data obtained on the operational performance of the test and waste-form durability will be used to assess the feasibility of applying the ISV technology to an actual waste trench

  9. Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

    International Nuclear Information System (INIS)

    Langton, C. A.; Stefanko, D. B.

    2013-01-01

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: 1) physically stabilize the final landfill by filling the empty volume in the tanks with a non-compressible material; 2) provide a barrier for inadvertent intrusion into the tank; 3) reduce contaminant mobility by a) limiting the hydraulic conductivity of the closed tank and b) reducing contact between the residual waste and infiltrating water; and 4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: 1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). 2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. 3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix design. 4

  10. Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C. A.; Stefanko, D. B.

    2013-04-23

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: 1) physically stabilize the final landfill by filling the empty volume in the tanks with a non-compressible material; 2) provide a barrier for inadvertent intrusion into the tank; 3) reduce contaminant mobility by a) limiting the hydraulic conductivity of the closed tank and b) reducing contact between the residual waste and infiltrating water; and 4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: 1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). 2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. 3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix design. 4

  11. In-situ anatase phase stabilization of titania photocatalyst by sintering in presence of Zr{sup 4+} organic salts

    Energy Technology Data Exchange (ETDEWEB)

    Strini, Alberto, E-mail: alberto.strini@itc.cnr.it [Istituto per le Tecnologie della Costruzione (ITC-CNR), via Lombardia, 49, I-20098 San Giuliano Milanese (MI) (Italy); Sanson, Alessandra; Mercadelli, Elisa [Istituto di Scienza e Tecnologia dei Materiali Ceramici (ISTEC-CNR), via Granarolo, 64, I-48018 Faenza (RA) (Italy); Bendoni, Riccardo [Istituto di Scienza e Tecnologia dei Materiali Ceramici (ISTEC-CNR), via Granarolo, 64, I-48018 Faenza (RA) (Italy); Dipartimento di Scienze e Tecnologie Chimiche e Centro NAST - Università di Roma Tor Vergata, via della Ricerca Scientifica, I-00133 Roma (Italy); Marelli, Marcello; Dal Santo, Vladimiro [CNR–Istituto di Scienze e Tecnologie Molecolari, via Golgi, 19, I-20133 Milano (Italy); Schiavi, Luca [Istituto per le Tecnologie della Costruzione (ITC-CNR), via Lombardia, 49, I-20098 San Giuliano Milanese (MI) (Italy)

    2015-08-30

    Graphical abstract: - Highlights: • Existing commercial (P25) anatase was stabilized in-situ with Zr(IV) doping. • Highly active catalytic layers were obtained by screen-printing. • Increased thermal stability was demonstrated up to 200 °C without activity loss. • Enhanced activity was obtained because of the Zr(IV) doping. • Zirconium diffusion was assessed by STEM-EDS analysis. - Abstract: The direct in-situ stabilization of an anatase-based nanocrystalline photocatalyst (Degussa P25) was obtained by sintering the catalyst powder in presence of Zr{sup 4+} organic salts. This approach allows the doping of an already-formed nanocrystalline photocatalyst instead of introducing the dopant in the crystal lattice during the catalyst synthesis. The procedure was demonstrated by the production of thick ceramic layers using the screen printing technique. This new method allows to easily stabilize the anatase phase 200 °C higher than the undoped P25 maintaining the same photocatalytic activity. The process was studied using specifically formulated screen-printing inks added with Zr{sup 4+} organic salt at 1% and 2% Zr/Ti molar ratio. The anatase phase stability was investigated in the 500–900 °C temperature range analysing the resulting catalysts with XRD, TEM and (S)TEM-EDS. The catalytic activity of the screen-printed layers was assessed by measuring the degradation of toluene in air at ambient concentration (500 nmol m{sup −3}) and low UV-A irradiance (180 μW cm{sup −2}). The described in-situ stabilization method could be potentially applied to any deposition process involving already formed anatase photocatalyst, allowing higher sintering temperature and then an improved mechanical stability of the active layers without photocatalytic activity degradation.

  12. In-situ anatase phase stabilization of titania photocatalyst by sintering in presence of Zr4+ organic salts

    International Nuclear Information System (INIS)

    Strini, Alberto; Sanson, Alessandra; Mercadelli, Elisa; Bendoni, Riccardo; Marelli, Marcello; Dal Santo, Vladimiro; Schiavi, Luca

    2015-01-01

    Graphical abstract: - Highlights: • Existing commercial (P25) anatase was stabilized in-situ with Zr(IV) doping. • Highly active catalytic layers were obtained by screen-printing. • Increased thermal stability was demonstrated up to 200 °C without activity loss. • Enhanced activity was obtained because of the Zr(IV) doping. • Zirconium diffusion was assessed by STEM-EDS analysis. - Abstract: The direct in-situ stabilization of an anatase-based nanocrystalline photocatalyst (Degussa P25) was obtained by sintering the catalyst powder in presence of Zr 4+ organic salts. This approach allows the doping of an already-formed nanocrystalline photocatalyst instead of introducing the dopant in the crystal lattice during the catalyst synthesis. The procedure was demonstrated by the production of thick ceramic layers using the screen printing technique. This new method allows to easily stabilize the anatase phase 200 °C higher than the undoped P25 maintaining the same photocatalytic activity. The process was studied using specifically formulated screen-printing inks added with Zr 4+ organic salt at 1% and 2% Zr/Ti molar ratio. The anatase phase stability was investigated in the 500–900 °C temperature range analysing the resulting catalysts with XRD, TEM and (S)TEM-EDS. The catalytic activity of the screen-printed layers was assessed by measuring the degradation of toluene in air at ambient concentration (500 nmol m −3 ) and low UV-A irradiance (180 μW cm −2 ). The described in-situ stabilization method could be potentially applied to any deposition process involving already formed anatase photocatalyst, allowing higher sintering temperature and then an improved mechanical stability of the active layers without photocatalytic activity degradation

  13. R20 Programme: The development of grouting technique. Stop criteria and field tests

    International Nuclear Information System (INIS)

    Hollmen, K.

    2008-01-01

    This work is a part of the project 'Grouting Technique' by Posiva Oy, which is responsible for the final disposal of spent nuclear fuel in Finland. This study attempts to collect disperse information about the design parameters of the grouting and about a field-test stop criterion, which differs from the prevailing practice. The literature study describes salient processes of grouting design in sufficient extent. Different methods for grouting stop criterion are described in more detail. Grouting design based on selected grouting theory, grouting and evaluating of the grouting results are presented in the experiential part of this study. This study focuses on rock tunnel grouting using cement-based grout. The requirements for water tightness, which are set down by customer, direct the grouting design. Information about fractures in rock mass, which surrounds the rock facility, is the prime initial data for grouting design. In grouting work, fracturing is generally studied by water loss measurements performed in investigation, probe and grouting holes. Besides the water loss measurement, the Posiva Flow Log -tool, which measures location and transmissivity for every single fracture, is used in ONKALO. Grouting pressure and grout must be chosen together and case-specifically. Both pressure and yield strength of grout are influencing the penetration length of grout in a fracture. Grouting pressure must be high enough to ensure sufficient penetration length, but pressure must be under the level where rock mass breaks to avoid hydraulic fracturing. Raising the water to dry material ratio reduces the yield strength of grout, in which case the grouting pressure can be lowered. Stop criterion for grouting aims to define the point, when the result of the grouting is adequate, and the grouting after that point is uneconomical. Properly specified stop criterion minimizes extra grout volume and reduces the running time of grouting work. From the references, three different

  14. Experimental Characterization of Stress- and Strain-Dependent Stiffness in Grouted Rock Masses.

    Science.gov (United States)

    Kim, Ji-Won; Chong, Song-Hun; Cho, Gye-Chun

    2018-03-29

    Grouting of fractured rock mass prior to excavation results in grout-filled discontinuities that govern the deformation characteristics of a site. The influence of joint characteristics on the properties of grouted rocks is important in assessing the effects of grouting on jointed rock mass. However, grouting remains a predominantly empirical practice and the effects of grouting on rock joint behavior and material properties have yet to be accurately assessed. Granular materials, including jointed rocks, typically display nonlinear strain-dependent responses that can be characterized by the shear modulus degradation curve. In this study, the effects of grouting on the strain-dependent shear stiffness of jointed rock mass were investigated at the small-strain (below 10 -5 ) and mid-strain (10 -5 to 10 -3 ) ranges using the quasi-static resonant column test and rock mass dynamic test devices. The effects of curing time, axial stress, initial joint roughness, and grouted joint thickness were examined. The results show that (1) grouting of rock joints leads to decreased stress sensitivity and increased small-strain shear stiffness for all tested samples; (2) the grouted rock samples display similar modulus degradation characteristics as the applied grout material; (3) the initial joint roughness determines the stress-dependent behaviors and general stiffness range of the jointed and grouted rocks, but the strain-dependent behaviors are dependent on the properties of the grout material; (4) increased grouted joint thickness results in larger contribution of the grout properties in the overall grouted rock mass.

  15. CsIX/TRU Grout Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    S. J. Losinski; C. M. Barnes; B. K. Grover

    1998-11-01

    A settlement agreement between the Department of Energy (DOE) and the State of Idaho mandates that liquid waste now stored at the Idaho Nuclear Technology Engineering Center (INTEC - formerly the Idaho Chemical Processing Plant, ICPP) will be calcined by the end of year 2012. This study investigates an alternative treatment of the liquid waste that removes undissolved solids (UDS) by filtration and removes cesium by ion exchange followed by cement-based grouting of the remaining liquid into 55-gal drums. Operations are assumed to be from January 2008 through December 2012. The grouted waste will be contact-handled and will be shipped to the Waste Isolation Pilot Plant (WIPP) in New Mexico for disposal. The small volume of secondary wastes such as the filtered solids and cesium sorbent (resin) would remain in storage at the Idaho National Engineering and Environmental Laboratory for treatment and disposal under another project, with an option to dispose of the filtered solids as a r emote-handled waste at WIPP.

  16. CsIX/TRU Grout Feasibility Study

    International Nuclear Information System (INIS)

    Losinski, S. J.; Barnes, C. M.; Grover, B. K.

    1998-01-01

    A settlement agreement between the Department of Energy (DOE) and the State of Idaho mandates that liquid waste now stored at the Idaho Nuclear Technology Engineering Center (INTEC - formerly the Idaho Chemical Processing Plant, ICPP) will be calcined by the end of year 2012. This study investigates an alternative treatment of the liquid waste that removes undissolved solids (UDS) by filtration and removes cesium by ion exchange followed by cement-based grouting of the remaining liquid into 55-gal drums. Operations are assumed to be FR-om January 2008 through December 2012. The grouted waste will be contact-handled and will be shipped to the Waste Isolation Pilot Plant (WIPP) in New Mexico for disposal. The small volume of secondary wastes such as the filtered solids and cesium sorbent (resin) would remain in storage at the Idaho National Engineering and Environmental Laboratory for treatment and disposal under another project, with an option to dispose of the filtered solids as a r emote-handled waste at WIPP

  17. Grout and vitrification formula development for immobilization of hazardous radioactive tank sludges at ORNL

    International Nuclear Information System (INIS)

    Gilliam, T.M.; Spence, R.D.

    1997-01-01

    Stabilization/solidification (S/S) has been identified as the preferred treatment option for hazardous radioactive sludges, and currently grouting and vitrification are considered the leading candidate S/S technologies. Consequently, a project was initiated at Oak Ridge National Laboratory (ORNL) to define composition envelopes, or operating windows, for acceptable grout and glass formulations containing Melton Valley Storage Tank (MVST) sludges. The resulting data are intended to be used as guidance for the eventual treatment of the MVST sludges by the government and/or private sector. Wastewater at ORNL is collected, evaporated, and stored in the MVSTs pending treatment for disposal. The waste separates into two phases: sludge and supernate. The sludges in the tank bottoms have been accumulating for several years and contain a high amount of radioactivity, with some classified as transuranic (TRU) sludges. The available total constituent analysis for the MVST sludge indicates that the Resource and Conservation Recovery Act (RCRA) metal concentrations are high enough to be potentially RCRA hazardous; therefore, these sludges have the potential to be designated as mixed TRU waste. S/S treatment must be performed to remove free liquids and reduce the leach rate of RCRA metals. This paper focuses on initial results for the development of the operating window for vitrification. However, sufficient data on grouting are presented to allow a comparison of the two options

  18. Grout and vitrification formula development for immobilization of hazardous radioactive tank sludges at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Gilliam, T.M.; Spence, R.D.

    1997-12-31

    Stabilization/solidification (S/S) has been identified as the preferred treatment option for hazardous radioactive sludges, and currently grouting and vitrification are considered the leading candidate S/S technologies. Consequently, a project was initiated at Oak Ridge National Laboratory (ORNL) to define composition envelopes, or operating windows, for acceptable grout and glass formulations containing Melton Valley Storage Tank (MVST) sludges. The resulting data are intended to be used as guidance for the eventual treatment of the MVST sludges by the government and/or private sector. Wastewater at ORNL is collected, evaporated, and stored in the MVSTs pending treatment for disposal. The waste separates into two phases: sludge and supernate. The sludges in the tank bottoms have been accumulating for several years and contain a high amount of radioactivity, with some classified as transuranic (TRU) sludges. The available total constituent analysis for the MVST sludge indicates that the Resource and Conservation Recovery Act (RCRA) metal concentrations are high enough to be potentially RCRA hazardous; therefore, these sludges have the potential to be designated as mixed TRU waste. S/S treatment must be performed to remove free liquids and reduce the leach rate of RCRA metals. This paper focuses on initial results for the development of the operating window for vitrification. However, sufficient data on grouting are presented to allow a comparison of the two options.

  19. In-situ anatase phase stabilization of titania photocatalyst by sintering in presence of Zr4+ organic salts

    Science.gov (United States)

    Strini, Alberto; Sanson, Alessandra; Mercadelli, Elisa; Bendoni, Riccardo; Marelli, Marcello; Dal Santo, Vladimiro; Schiavi, Luca

    2015-08-01

    The direct in-situ stabilization of an anatase-based nanocrystalline photocatalyst (Degussa P25) was obtained by sintering the catalyst powder in presence of Zr4+ organic salts. This approach allows the doping of an already-formed nanocrystalline photocatalyst instead of introducing the dopant in the crystal lattice during the catalyst synthesis. The procedure was demonstrated by the production of thick ceramic layers using the screen printing technique. This new method allows to easily stabilize the anatase phase 200 °C higher than the undoped P25 maintaining the same photocatalytic activity. The process was studied using specifically formulated screen-printing inks added with Zr4+ organic salt at 1% and 2% Zr/Ti molar ratio. The anatase phase stability was investigated in the 500-900 °C temperature range analysing the resulting catalysts with XRD, TEM and (S)TEM-EDS. The catalytic activity of the screen-printed layers was assessed by measuring the degradation of toluene in air at ambient concentration (500 nmol m-3) and low UV-A irradiance (180 μW cm-2). The described in-situ stabilization method could be potentially applied to any deposition process involving already formed anatase photocatalyst, allowing higher sintering temperature and then an improved mechanical stability of the active layers without photocatalytic activity degradation.

  20. Experimental assessment of the sealing effectiveness of rock fracture grouting

    International Nuclear Information System (INIS)

    Schaffer, A.; Daemen, J.J.K.

    1987-03-01

    The objective of this investigation is to determine the effectiveness of cement grouts as sealants of fractures in rock. Laboratory experiments have been conducted on seven 15-cm granite cubes containing saw cuts, three 23-cm diameter andesite cores containing induced tension cracks, and one 15-cm diameter marble core containing a natural fracture. Prior to grouting, the hydraulic conductivity of the fractures is determined under a range of normal stresses, applied in loading and unloading cycles, from 0 to 14 MPa (2000 psi). Grout is injected through an axial borehole, at a pressure of 1.2 to 8.3 MPa (180 to 1200 psi), pressure selected to provide a likely groutable fracture aperture, while the fracture is stressed at a constant normal stress. The fracture permeability is measured after grouting. Flow tests on the ungrouted samples confirm the inverse relation between normal stress and fracture permeability. The equivalent aperture determined by these tests is a reliable indicator of groutability. Postgrouting permeability measurements as performed here, and frequently in practice, can be misleading, since incomplete grouting of fractures can result in major apparent reductions in permeability. The apparent permeability reduction is caused by grouting of a small area of a highly preferential flowpath directly adjacent to the hole used for grouting and for permeability testing. Experimental results confirm claims in the literature that ordinary portland cement inadequately penetrates fine fractures

  1. Effects of Coal Gangue on Cement Grouting Material Properties

    Science.gov (United States)

    Liu, J. Y.; Chen, H. X.

    2018-05-01

    The coal gangue is one of the most abundant industrial solid wastes and pollute source of air and water. The use of coal gangue in the production of cement grouting material comforms to the basic state policy of environment protection and the circular using of natural resources. Through coal gangue processing experiment, coal gangue cement grouting materials making test, properties detection of properties and theoretical analysis, the paper studied the effects of coal gangue on the properties of cement grouting materials. It is found that at the range of 600 to 700 °C, the fluidity and the compressive and flexural strengths of the cement grouting materials increase with the rising up of the calcination temperatures of coal gangue. The optimum calcination temperature is around 700 °C. The part substitution of cement by the calcined coal gangue in the cement grouting material will improve the mechanical properties of the cement grouting material, even thought it will decrease its fluidity. The best substitution amount of cement by coal gangue is about 30%. The fluidity and the long term strength of the ordinary silicate cement grouting material is obviously higher than that of the sulphoaluminate cement one as well as that of the silicate-sulphoaluminate complex cement one.

  2. R20 Programme: Field testing of grouting materials

    International Nuclear Information System (INIS)

    Ranta-Korpi, R.; Karttunen, P.; Sievaenen, U.

    2008-02-01

    In the year 2004 Finnish nuclear waste management organisation Posiva Oy started to construct an underground rock characterisation facility in Olkiluoto, Eurajoki, Western Finland. The ONKALO was planned to be a final disposal of spent nuclear fuel in Finland. This facility is going to be finished in the end of the year 2010. In ONKALO it is important to grout the water conductive structures to minimize the leakage of the inflowing groundwater in order to keep the geohydrogical environment unchanged and the repository conditions safe. Before the construction began the development of the grouts suitable for this demanding environment was started. Especially pH, the penetration ability and rheology have been the matter of interest. One target for the grout has been that the pH is relatively low. These grouts have different properties than the normal grouts. Several laboratory and field tests have been done for low pH grouts. The suitable recipies are studied in laboratory and the properties are verified in field. This work concerns the field testing of several low pH grout recipies. The different W/DM -ratios and SPL contents were studied. Besides the customary test methods, two new measurement methods were taken into use: the sand column test for measuring the penetration ability and the stick test for determining the plastic viscosity and yield value. The relationships between different properties, the properties as a function of the time and the effect of the (orig.)

  3. The differences between soil grouting with cement slurry and cement-water glass slurry

    Science.gov (United States)

    Zhu, Mingting; Sui, Haitong; Yang, Honglu

    2018-01-01

    Cement slurry and cement-water glass slurry are the most widely applied for soil grouting reinforcement project. The viscosity change of cement slurry is negligible during grouting period and presumed to be time-independent while the viscosity of cement-water glass slurry increases with time quickly and is presumed to be time-dependent. Due to the significantly rheology differences between them, the grouting quality and the increasing characteristics of grouting parameters may be different, such as grouting pressure, grouting surrounding rock pressure, i.e., the change of surrounding rock pressure deduced by grouting pressure. Those are main factors for grouting design. In this paper, a large-scale 3D grouting simulation device was developed to simulate the surrounding curtain grouting for a tunnel. Two series of surrounding curtain grouting experiments under different geo-stress of 100 kPa, 150 kPa and 200 kPa were performed. The overload test on tunnel was performed to evaluate grouting effect of all surrounding curtain grouting experiments. In the present results, before 240 seconds, the grouting pressure increases slowly for both slurries; after 240 seconds the increase rate of grouting pressure for cement-water glass slurry increases quickly while that for cement slurry remains roughly constant. The increasing trend of grouting pressure for cement-water glass is similar to its viscosity. The setting time of cement-water glass slurry obtained from laboratory test is less than that in practical grouting where grout slurry solidifies in soil. The grouting effect of cement-water glass slurry is better than that of cement slurry and the grouting quality decreases with initial pressure.

  4. Superplasticizer function and sorption in high performance cement based grouts

    International Nuclear Information System (INIS)

    Onofrei, M.; Gray, M.N.; Roe, L.H.

    1991-08-01

    This report describes laboratory studies undertaken to determine interactions between the main components of high-performance cement-based grout. These interactions were studied with the grouts in both their unset and hardened states with the specific intention of determining the following: the mechanistic function of superplasticizer; the phase of residence of the superplasticizer in hardened materials; and the permanence of the superplasticizer in hardened grouts. In unset pastes attempts were made to extract superplasticizer by mechanical processes. In hardened grout the superplasticizer was leached from the grouts. A microautoradiographic method was developed to investigate the phases of residence of superplasticizer in hardened grouts and confirm the inferences from the leaching studies. In hardened grout the superplasticizer was located on the hydrated phases formed during the early stages of cement hydration. These include tricalcium aluminate hydrates and tricalcium silicate phases. There is some tendency for the superplasticizer to sorb on ettringite. The presence of superplasticizer did not coincide with the locations of unreacted silica fume and high silica content phases such as C 2 S-H. The observations explain the findings of the studies of unset pastes which also showed that the sorption of superplasticizer is likely to be enhanced with increased mixing water content and, hence, distribution in and exposure to the hydration reaction surfaces in the grout. Superplasticizer can be leached in very small quantities from the hardened grouts. Rapid release takes place from the unsorbed superplasticizer contained in the accessible pore space. Subsequent release likely occurs with dissolution of the cement phases and the exposure of isolated pores to groundwater. (au) (37 refs.)

  5. Probabilistic structural assessment of conical grouted joint using numerical modelling

    DEFF Research Database (Denmark)

    Njomo-Wandji, Wilfried; Natarajan, Anand; Dimitrov, Nikolay

    2018-01-01

    Conical grouted joints have been proposed as a solution for the relative settlement observed between the sleeve and the pile on monopiles for wind turbines. In this paper, the influence of the design parameters such as steel wall thicknesses and conical angle on the failure modes associated...... to continual loadings are assessed based on finite element analysis. It is found that both the sleeve's and pile's wall thicknesses have a significant impact on the grouted joint health. Namely, the larger are the wall thicknesses, the more vulnerable the grout is with respect to fatigue and material...

  6. Injection grout for deep repositories - Low-pH cementitious grout for larger fractures. Field testing in Finland, Pilot tests

    International Nuclear Information System (INIS)

    Sievaeen, U.; Syrjaenen, P.; Ranta-aho, S.

    2005-10-01

    Posiva, SKB and NUMO have cooperated for developing a low pH injection grout for sealing of the deep repositories for spent nuclear fuel. A project 'Injection grout for deep repositories' was divided into four subprojects. The development of low pH cementitious grout for > 100 μm fractures was carried out in Finland. The development of non-cementitious low pH grout for < 100 μm fractures was carried out in Sweden. This report concerns the cementitious grout. Requirements for pH and penetration ability were set for the grouts to be developed. Besides these, the grouts were desired to fulfil certain targets set for viscosity, bleeding, shear strength, yield value, compressive strength and open time. Also durability, availability of the components and known history in practical engineering were given as requirements. The object of the work presented here was to test if the grout properties developed in laboratory can be met in field conditions. Only the most promising binder material combinations, which have fulfilled the main requirements in laboratory, were tested in field. Evaluations of environmental aspects are included in this report. In the pilot test 1, carried out in a multi-purpose tunnel in Helsinki, Portland cement-cilicasystem and blast furnace slag-based system were chosen to be tested. In field conditions, mixed with ordinary mixer, all grout properties achieved in laboratory, were not verified. Penetration ability was typically good, but fluidity and strength development were not satisfying. The main conclusion was that water to dry material ratio should be diminished. In order to get better rheological properties at the same time, superplastizicer was needed in further development of the mixes. Also accurate dosing and mixing seemed to be very important. Blast furnace slag - system was after this pilot test ruled out due to high leaching of sulphide from the product, not due to the bad technical properties. The development work continued with

  7. Field grouting summary report on the WAG seeps 4 and 6 removal action project, Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 1: Text

    International Nuclear Information System (INIS)

    1997-05-01

    During the summer of 1996, a unique multi-phase, multi-stage, low-pressure permeation grouting pilot program was performed inside portions of four unlined waste disposal trenches at Waste Area Grouping (WAG) 4 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The project was deemed a non-time-critical removal action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); however, due to a history of heavy precipitation in the fall, the schedule was fast-tracked to meet an October 31, 1996 grouting completion date. The technical objective of the removal action was to reduce the off-site transport of Strontium 90 ( 90 Sr) by grouting portions of four waste disposal trenches believed to be responsible for over 70% of the 90 Sr leaving the site. A goal of the grouting operation was to reduce the average in situ hydraulic conductivity of the grouted waste materials to a value equal to or less than 1 x 10 -6 cm/sec. This target hydraulic conductivity value was established to be at least two orders of magnitude lower than that of the surrounding natural ground

  8. Field grouting summary report on the WAG 4 seeps 4 and 6 removal action project, Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 3. Appendixes E and F

    International Nuclear Information System (INIS)

    1997-05-01

    During the summer of 1996, a unique multi-phase, multi-stage, low-pressure permeation grouting pilot program was performed inside portions of four unlined waste disposal trenches at Waste Area Grouping (WAG) 4 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The project was deemed a non-time-critical removal action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); however, due to a history of heavy precipitation in the fall, the schedule was fast-tracked to meet an October 31, 1996 grouting completion date. The technical objective of the removal action was to reduce the off-site transport of j Strontium 90 ( 90 Sr) by grouting portions of four waste disposal trenches believed to be responsible for over 70 percent of the 90 Sr leaving the site. A goal of the grouting operation was to reduce the average in situ hydraulic conductivity of the grouted waste materials to a value equal to or less than 1 x 10 -6 cm/sec. This target hydraulic conductivity value was established to be at least two orders of magnitude lower than that of the surrounding natural ground

  9. Field grouting summary report on the WAG 4 seeps 4 and 6 removal action project, Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 3. Appendixes E and F

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    During the summer of 1996, a unique multi-phase, multi-stage, low-pressure permeation grouting pilot program was performed inside portions of four unlined waste disposal trenches at Waste Area Grouping (WAG) 4 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The project was deemed a non-time-critical removal action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); however, due to a history of heavy precipitation in the fall, the schedule was fast-tracked to meet an October 31, 1996 grouting completion date. The technical objective of the removal action was to reduce the off-site transport of j Strontium 90 ({sup 90}Sr) by grouting portions of four waste disposal trenches believed to be responsible for over 70 percent of the {sup 90}Sr leaving the site. A goal of the grouting operation was to reduce the average in situ hydraulic conductivity of the grouted waste materials to a value equal to or less than 1 x 10{sup -6} cm/sec. This target hydraulic conductivity value was established to be at least two orders of magnitude lower than that of the surrounding natural ground.

  10. Evaluation of dry-solids-blend material source for grouts containing 106-AN waste: September 1990 progress report

    International Nuclear Information System (INIS)

    Gilliam, T.M.; Osborne, S.C.; Francis, C.L.; Scott, T.C.

    1993-09-01

    Stabilization/solidification (S/S) is the most widely used technology for the treatment and ultimate disposal of both radioactive and chemically hazardous wastes. Such technology is being utilized in a Grout Treatment Facility (GTF) by the Westinghouse Hanford Company (WHC) for the disposal of various wastes, including 106-AN wastes, located on the Hanford Reservation. The WHC personnel have developed a grout formula for 106-AN disposal that is designed to meet stringent performance requirements. This formula consists of a dry-solids blend containing 40 wt % limestone, 28 wt % granulated blast furnace slag (BFS), 28 wt % ASTM Class F fly ash, and 4 wt % Type I-II-LA Portland cement. The blend is mixed with 106-AN waste at a ratio of 9 lb of dry-solids blend per gallon of waste. This report documents progress made to date on efforts at Oak Ridge National Laboratory (ORNL) in support of WHC's Grout Technology Program to assess the effects of the source of the dry-solids-blend materials on the resulting grout formula

  11. Tanks 18 And 19-F Structural Flowable Grout Fill Material Evaluation And Recommendations

    International Nuclear Information System (INIS)

    Stefanko, D.; Langton, C.

    2011-01-01

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: (1) physically stabilize the final landfill by filling the empty volume in the tanks with a non compressible material; (2) provide a barrier for inadvertent intrusion into the tank; (3) reduce contaminant mobility by (a) limiting the hydraulic conductivity of the closed tank and (b) reducing contact between the residual waste and infiltrating water; and (4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: (1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). (2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. (3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix

  12. TANKS 18 AND 19-F STRUCTURAL FLOWABLE GROUT FILL MATERIAL EVALUATION AND RECOMMENDATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Stefanko, D.; Langton, C.

    2011-11-01

    Cementitious grout will be used to close Tanks 18-F and 19-F. The functions of the grout are to: (1) physically stabilize the final landfill by filling the empty volume in the tanks with a non compressible material; (2) provide a barrier for inadvertent intrusion into the tank; (3) reduce contaminant mobility by (a) limiting the hydraulic conductivity of the closed tank and (b) reducing contact between the residual waste and infiltrating water; and (4) providing an alkaline, chemically reducing environment in the closed tank to control speciation and solubility of selected radionuclides. The objective of this work was to identify a single (all-in-one) grout to stabilize and isolate the residual radionuclides in the tank, provide structural stability of the closed tank and serve as an inadvertent intruder barrier. This work was requested by V. A. Chander, High Level Waste (HLW) Tank Engineering, in HLW-TTR-2011-008. The complete task scope is provided in the Task Technical and QA Plan, SRNL-RP-2011-00587 Revision 0. The specific objectives of this task were to: (1) Identify new admixtures and dosages for formulating a zero bleed flowable tank fill material selected by HLW Tank Closure Project personnel based on earlier tank fill studies performed in 2007. The chemical admixtures used for adjusting the flow properties needed to be updated because the original admixture products are no longer available. Also, the sources of cement and fly ash have changed, and Portland cements currently available contain up to 5 wt. % limestone (calcium carbonate). (2) Prepare and evaluate the placement, compressive strength, and thermal properties of the selected formulation with new admixture dosages. (3) Identify opportunities for improving the mix selected by HLW Closure Project personnel and prepare and evaluate two potentially improved zero bleed flowable fill design concepts; one based on the reactor fill grout and the other based on a shrinkage compensating flowable fill mix

  13. SAVANNAH RIVER SITE R REACTOR DISASSEMBLY BASIN IN SITU DECOMMISSIONING

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Blankenship, J.; Griffin, W.; Serrato, M.

    2009-12-03

    The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate if from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,424 cubic meters or 31,945 cubic yards. Portland cement-based structural fill materials were design and tested for the reactor ISD project and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and work flow considerations, the recommended maximum lift height is 5 feet with 24 hours between lifts. Pertinent data and information related to the SRS 105-R-Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material designs

  14. R20 programme: Development of rock grouting design, techniques and procedures for ONKALO

    International Nuclear Information System (INIS)

    Sievaenen, U.

    2009-02-01

    Posiva Oy constructs an underground research facility ONKALO at Olkiluoto in Eurajoki. ONKALO is planned to be a part of the deep repository for the high level nuclear waste. Posiva Oy set up R20-programme for the years 2006-2008, with the target of having an acceptable grouting methodology in ONKALO. The programme was divided into three projects and the work and results of Technique-project is presented in this report. The implementation of the results (grouting design and execution) was outlined from the project. That work is under the responsibility of construction of the ONKALO-project. The Grouting Technique -project (INKE) studied the grouting experiences obtained from the first 2 km of the ONKALO access tunnel, searched for suitable grouting design approaches, carried out two grouting tests and one pilot grouting test with colloidal silica in ONKALO, analysed the expected grouting conditions in deep rock from the grouting point of view, studied the feasibility of so called optimal design solution in the expected grouting conditions. Based on these studies recommendations concerning the grouting design, design solutions for different rock conditions, grouting procedures, grouting stop criteria, the characterisation methods for grouting purposes, grouting materials and grouting work performance are presented. Swedish Time Stop Grouting, also named Grouting Time-Method was selected to be studied and used in this project and it was further developed. This work compiles the outcome of the project subtasks and presents the recommendations for developing the grouting in ONKALO. The key conclusion of this work are: (1) Grouting Time-method (time stop grouting) alone is not enough to be used as a grouting stop criterion due to the uncertainties related to the source parameters (fracture characteristics, rheological properties of grouts); these cause too high uncertainties when proving the sealing result via the grouting time, (2) due to the uncertainties related to

  15. Leaching of radioactive nuclides from cement grouts. Part II

    International Nuclear Information System (INIS)

    Stanley, W.T.; Avgerinos, G.F.; Gonzalez, B.; Hemley, P.J.

    1974-01-01

    The determination of the leaching rate of radioactive 137 Cs from a cement grout should the grout be contacted by water is necessary for environmental protection. The effect of the leachant turnover rate on 137 Cs leaching rates was evaluated with batch and continuous (modified Soxhlet extractor) modes of experimentation. Three additives (Grundite, potter's clay, and Conasauga shale) were compared in terms of capability of radioactive isotope retention, while two leachants (tap and distilled water) were investigated. The Soxhlet extractor experiment resulted in the highest rate of leaching, and Conasauga shale was found the best additive for 137 Cs immobilization. Tap water used as leachant was more effective than distilled water. Data were analyzed using models involving isotopic diffusion in the grout and involving diffusion plus a time dependent boundary condition at the interface of grout specimen and leachant

  16. The role of capital realignment versus in situ stabilization for the treatment of slipped capital femoral epiphysis.

    Science.gov (United States)

    Souder, Christopher D; Bomar, James D; Wenger, Dennis R

    2014-12-01

    Slipped capital femoral epiphysis (SCFE) can be treated by a variety of methods with the traditional method of in situ pin fixation being most commonly used. More recently, the Modified Dunn (Mod. Dunn) procedure consisting of capital realignment has been popularized as a treatment method for SCFE, particularly for more severe cases. Over the last 5 years, our institution has selectively used this method for more complex cases. The purpose of this article is to evaluate the differences between these 2 treatment methods in terms of avascular necrosis (AVN) rate, reoperation rate, and complication rate. Eighty-eight hips that were surgically treated for SCFE between July 2004 and June 2012 met our inclusion criteria. The in situ fixation group included 71 hips, whereas 17 hips were anatomically reduced with the Mod. Dunn procedure. Loder classification, severity, acuity, complication rate, and reoperation rate were determined for the 2 cohorts. The χ analysis was performed to evaluate the relationship between the treatment method and outcome. As expected, stable slips did well with in situ pinning with no cases of AVN, even in more severe slips. Ten stable slips were treated with the Mod. Dunn approach and 2 (20%) developed AVN. Unstable slips were more difficult to treat with 3 of the 7 hips stabilized in situ developing AVN (43%). Two of the 7 unstable slips treated by the Mod. Dunn procedure developed AVN (29%). The other outcomes studied (reoperation rate and complication rate) were not significantly related to the surgical treatment method (P = 0.732 and 0.261, respectively). In situ pinning remains a safe and predictable method for treatment of stable SCFE with no AVN noted, even in severe slips. Attempts to anatomically reduce stable slips led to severe AVN in 20% of cases, thus this treatment approach should be considered with caution. Treatment of unstable slips remains problematic with high AVN rates noted whether treated by in situ fixation or capital

  17. experimental study of cement grout: rheological behavior and sedimentation

    OpenAIRE

    Rosquoët , Frédéric; Alexis , Alain ,; Khelidj , Abdelhafid; Phelipot-Mardelé , Annabelle

    2002-01-01

    International audience; Three basic elements (cement, water and admixture) usually make up injectable cement grouts used for prestressed cable coating, repair and consolidation of masonry, soil grouting, etc... The present study was divided into two parts. First, in order to characterize rheologically fresh cement paste with W/C ratios (water/cement ratio) varying between 0.35 and 1, an experimental study was carried out and has revealed that the cement past behaves like a shear-thinning mate...

  18. Liquid Secondary Waste Grout Formulation and Waste Form Qualification

    Energy Technology Data Exchange (ETDEWEB)

    Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, B. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-05-23

    This report describes the results from liquid secondary waste (LSW) grout formulation and waste form qualification tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate new formulations for preparing a grout waste form with high-sulfate secondary waste simulants and the release of key constituents from these grout monoliths. Specific objectives of the LSW grout formulation and waste form qualification tests described in this report focused on five activities: 1.preparing new formulations for the LSW grout waste form with high-sulfate LSW simulants and solid characterization of the cured LSW grout waste form; 2.conducting the U.S. Environmental Protection Agency (EPA) Method 1313 leach test (EPA 2012) on the grout prepared with the new formulations, which solidify sulfate-rich Hanford Tank Waste Treatment and Immobilization Plant (WTP) off-gas condensate secondary waste simulant, using deionized water (DIW); 3.conducting the EPA Method 1315 leach tests (EPA 2013) on the grout monoliths made with the new dry blend formulations and three LSW simulants (242-A evaporator condensate, Environmental Restoration Disposal Facility (ERDF) leachate, and WTP off-gas condensate) using two leachants, DIW and simulated Hanford Integrated Disposal Facility (IDF) Site vadose zone pore water (VZPW); 4.estimating the 99Tc desorption Kd (distribution coefficient) values for 99Tc transport in oxidizing conditions to support the IDF performance assessment (PA); 5.estimating the solubility of 99Tc(IV)-bearing solid phases for 99Tc transport in reducing conditions to support the IDF PA.

  19. Evaluating the Long-Term Stability of Metals Precipitated In-Situ

    Science.gov (United States)

    Because metals (including metals and metalloids) cannot be destroyed, unlike organic contaminants, in-situ approaches for their removal from groundwater necessarily involves fixation/immobilization in the solid aquifer matrix. Consequently, the success of precipitation based in...

  20. Real Time Grouting Control Method. Development and application using Aespoe HRL data

    International Nuclear Information System (INIS)

    Kobayashi, Shinji; Stille, Haakan; Gustafson, Gunnar; Stille, Bjoern

    2008-10-01

    The spread of grout is governed by a number of complex relations. The desired results, such as grout penetration and sealing of fractures, cannot be directly measured during the grouting process. This means that the issue of how or when the injection of grout should be stopped cannot be answered by simple rules of thumb. This is also the background to the great variety of empirical rules used in the grouting sector worldwide. The research during recent years has given a better understanding of the water-bearing structures of the rock mass as well as analytical solutions. In this report the methodology has been further studied and a method for design and control of rock grouting has been proposed. The concept of what we call the 'Real Time Grouting Control Method' is to calculate the grout penetration and control grouting in real time by applying the development of the theories for grout spread. Our intention is to combine our method with a computerized logging tool to acquire an active tool in order to be able to govern the grout spread in real time during the grouting operation. The objectives of this report are: to further develop the theory concerning the relationship between grout penetration and grouting time to describe the real course of grouting, to establish the concept of 'Real Time Grouting Control Method' for design and control for rock grouting based on the developed theory, and to verify the concept by using the field data from the grouting experiment at the 450 m level in the Aespoe HRL. In this report, the approximations and analysis of dimensionality have been checked and further developments of the theory with respect to varying grouting pressure, time-dependent grout properties, changing grout mixes, and changing the flow dimension of the fracture have been carried out. The concept of 'Real Time Grouting Control Method' has been described in order to calculate the grout penetration and to control grouting in real time by applying developed

  1. Biological toxicity evaluation of Hanford Site waste grouts

    International Nuclear Information System (INIS)

    Rebagay, T.V. Dodd, D.A.; Voogd, J.A.

    1992-10-01

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 50 years of operation of the Hanford Site of the US Department of Energy near Richland, Washington. These wastes are currently stored onsite in single- and double-shell carbon steel tanks. To effectively handle and treat these wastes, their degree of toxicity must be determined. The disposal of the low-level radioactive liquid portion of the wastes involves mixing the wastes with pozzolanic blends to form grout. Potential environmental hazards posed by grouts are largely unknown. Biological evaluation of grout toxicity is needed to provide information on the potential risks of animal and plant exposure to the grouts. The fish, rat, and Microtox toxicity tests described herein indicate that the grouts formed from Formulations I and 2 are nonhazardous and nondangerous. Using the Microtox solid-phase protocol, both soluble and insoluble organic and inorganic toxicants in the grouts can be detected. This protocol may be used for rapid screening of environmental pollutants and toxicants

  2. Pilot-scale grout production test with a simulated low-level waste

    International Nuclear Information System (INIS)

    Fow, C.L.; Mitchell, D.H.; Treat, R.L.; Hymas, C.R.

    1987-05-01

    Plans are underway at the Hanford Site near Richland, Washington, to convert the low-level fraction of radioactive liquid wastes to a grout form for permanent disposal. Grout is a mixture of liquid waste and grout formers, including portland cement, fly ash, and clays. In the plan, the grout slurry is pumped to subsurface concrete vaults on the Hanford Site, where the grout will solidify into large monoliths, thereby immobilizing the waste. A similar disposal concept is being planned at the Savannah River Laboratory site. The underground disposal of grout was conducted at Oak Ridge National Laboratory between 1966 and 1984. Design and construction of grout processing and disposal facilities are underway. The Transportable Grout Facility (TGF), operated by Rockwell Hanford Operations (Rockwell) for the Department of Energy (DOE), is scheduled to grout Phosphate/Sulfate N Reactor Operations Waste (PSW) in FY 1988. Phosphate/Sulfate Waste is a blend of two low-level waste streams generated at Hanford's N Reactor. Other wastes are scheduled to be grouted in subsequent years. Pacific Northwest Laboratory (PNL) is verifying that Hanford grouts can be safely and efficiently processed. To meet this objective, pilot-scale grout process equipment was installed. On July 29 and 30, 1986, PNL conducted a pilot-scale grout production test for Rockwell. During the test, 16,000 gallons of simulated nonradioactive PSW were mixed with grout formers to produce 22,000 gallons of PSW grout. The grout was pumped at a nominal rate of 15 gpm (about 25% of the nominal production rate planned for the TGF) to a lined and covered trench with a capacity of 30,000 gallons. Emplacement of grout in the trench will permit subsequent evaluation of homogeneity of grout in a large monolith. 12 refs., 34 figs., 5 tabs

  3. Pressurized grout remote backfilling at AML sites near Beulah and Zap, North Dakota

    International Nuclear Information System (INIS)

    Weiner, E.J.; Dodd, W.E.

    1999-01-01

    The Abandoned Mine Lands (AML) Division of the North Dakota Public Service Commission (PSC) is charged with the reclamation of hazardous abandoned mine sites in North Dakota. Several underground lignite coalmines were operated near the cities of Beulah and Zap, North Dakota, from the early 1900's until about 1955. Coal seams in this area were relatively thick and the overburden generally shallow. As these mines have deteriorated with time, deep collapse features, or sinkholes, have surfaced in many areas. These features are very dangerous, especially when they occur at or near residential and commercial areas and public roads. In the past five years, sinkholes have surfaced beneath a commercial building (boat dealership, lounge, and gas station) and beneath a nearby occupied mobile home north of Beulah. sinkholes have also surfaced near KHOL Radio Station in Beulah and in the right of way of a public road south of Zap. The AML Division has conducted several emergency sinkhole-filling projects in these areas. In 1995--97, the AML Division conducted exploratory drilling which confirmed the presence of collapsing underground mines at these sites. The remediation of these sites around Beulah/Zap will take place over several years and involve three or more separate contracts due to budget considerations. In 1997, the AML Division began reclamation at these sties utilizing pressurized grout remote backfilling. In this technique, a cementitious grout is pumped through cased drill holes directly into the mine cavities to fill them and thereby stabilize the surface from collapse. The successful contractor for Phase One of the project was The Concrete Doctor, Inc. (TCDI). This paper will concentrate on Phase One of this work performed from June through September 1997. This project is especially interesting because grout was pumped through holes drilled inside the occupied commercial building. Grout was also pumped through angled holes that intercepted mined workings directly

  4. Pressurized grout remote backfilling at AML sites near Beulah and Zap, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    Weiner, E.J.; Dodd, W.E.

    1999-07-01

    The Abandoned Mine Lands (AML) Division of the North Dakota Public Service Commission (PSC) is charged with the reclamation of hazardous abandoned mine sites in North Dakota. Several underground lignite coalmines were operated near the cities of Beulah and Zap, North Dakota, from the early 1900's until about 1955. Coal seams in this area were relatively thick and the overburden generally shallow. As these mines have deteriorated with time, deep collapse features, or sinkholes, have surfaced in many areas. These features are very dangerous, especially when they occur at or near residential and commercial areas and public roads. In the past five years, sinkholes have surfaced beneath a commercial building (boat dealership, lounge, and gas station) and beneath a nearby occupied mobile home north of Beulah. sinkholes have also surfaced near KHOL Radio Station in Beulah and in the right of way of a public road south of Zap. The AML Division has conducted several emergency sinkhole-filling projects in these areas. In 1995--97, the AML Division conducted exploratory drilling which confirmed the presence of collapsing underground mines at these sites. The remediation of these sites around Beulah/Zap will take place over several years and involve three or more separate contracts due to budget considerations. In 1997, the AML Division began reclamation at these sties utilizing pressurized grout remote backfilling. In this technique, a cementitious grout is pumped through cased drill holes directly into the mine cavities to fill them and thereby stabilize the surface from collapse. The successful contractor for Phase One of the project was The Concrete Doctor, Inc. (TCDI). This paper will concentrate on Phase One of this work performed from June through September 1997. This project is especially interesting because grout was pumped through holes drilled inside the occupied commercial building. Grout was also pumped through angled holes that intercepted mined workings

  5. Predicting the Occurrence of Hydraulic Fracture in Grouting Operations Based on the Pressure in the Penetrated Cement Grout

    Directory of Open Access Journals (Sweden)

    Hassan Bakhshandeh Amnieh

    2017-12-01

    Full Text Available Cement grouting is an operation often carried out to consolidate and seal the rock mass in dam sites and tunnels. The quality and efficiency of a grouting operation depends on various factors such as water take, grout properties and grouting pressure. One of the parameters which have the highest effect is pressure since the application of excessive pressure causes the hydraulic fracture phenomenon to occur in the rock mass and too little pressure leads to incomplete grouting and failure to seal the site in a perfect manner. Mathematical modeling is used for the first time in this study to predict and determine the optimum pressure. Thus, the joints that exist in the rock mass are simulated using cylindrical shell model. The joint surroundings are also modeled through Pasternak environment. To obtain equations governing the joints and the surroundings, energy method is used accompanied by Hamilton principle. In the end, an analytical solution method is used to obtain the maximum grouting pressure. In order to validate the modeling, the grouting pressure values obtained by the model were used in the sites of Seymareh and Aghbolagh dams and the relative error rates were measured considering the differences between calculated and actual pressures. Modeling in the examined sections of Seymareh dam showed 29.61, 5.57, 21.98, 32.50 and 9.09 percent error rates and in the sections of Aghbolagh dam it rendered the values of 4.32, 5.40 and 2.96 percent. The results indicate that this modeling can be used to estimate the amount of pressure for hydraulic fracture in grouting, to predict it and to prevent it.

  6. Data report on the Waste Isolation Pilot Plant Small-Scale Seal Performance Test, Series F grouting experiment

    International Nuclear Information System (INIS)

    Ahrens, E.H.; Dale, T.F.; Van Pelt, R.S.

    1996-03-01

    SSSPT-F was designed to evaluate sealing materials at WIPP. It demonstrated: (1) the ability to practically and consistently produce ultrafine cementitious grout at the grouting site, (2) successful, consistent, and efficient injection and permeation of the grout into fractured rock at the repository horizon, (3) ability of the grout to penetrate and seal microfractures, (4) procedures and equipment used to inject the grout. Also techniques to assess the effectiveness of the grout in reducing the gas transmissivity of the fractured rock were evaluated. These included gas-flow/tracer testing, post-grout coring, pre- and post-grout downhole televiewer logging, slab displacement measurements, and increased loading on jacks during grout injection. Pre- and post-grout diamond drill core was obtained for use in ongoing evaluations of grouting effectiveness, degradation, and compatibility. Diamond drill equipment invented for this test successfully prevented drill cuttings from plugging fractures in grout injection holes

  7. Data report on the Waste Isolation Pilot Plant Small-Scale Seal Performance Test, Series F grouting experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ahrens, E.H. [Sandia National Labs., Albuquerque, NM (United States); Dale, T.F.; Van Pelt, R.S. [INTERA, Inc., Austin, TX (United States)

    1996-03-01

    SSSPT-F was designed to evaluate sealing materials at WIPP. It demonstrated: (1) the ability to practically and consistently produce ultrafine cementitious grout at the grouting site, (2) successful, consistent, and efficient injection and permeation of the grout into fractured rock at the repository horizon, (3) ability of the grout to penetrate and seal microfractures, (4) procedures and equipment used to inject the grout. Also techniques to assess the effectiveness of the grout in reducing the gas transmissivity of the fractured rock were evaluated. These included gas-flow/tracer testing, post-grout coring, pre- and post-grout downhole televiewer logging, slab displacement measurements, and increased loading on jacks during grout injection. Pre- and post-grout diamond drill core was obtained for use in ongoing evaluations of grouting effectiveness, degradation, and compatibility. Diamond drill equipment invented for this test successfully prevented drill cuttings from plugging fractures in grout injection holes.

  8. Engineering grouts - materials and applications with specific examples from Ra asthan Atomic Power Pro ect

    International Nuclear Information System (INIS)

    Singha Roy, P.K.; Sachchidanand; Sukhthankar, K.D.

    1978-01-01

    Grouting, though not very significant costwise, is an important aspect6 of construction in most of the major projects. According to modern construction technology, grouts have very stringent and diverse uses. The materials and practices generally found in India for grouting, mainly for structural grouts upto the middle of this decade are outlined along with details of specific grouts used in the construction of the twin reactor (440 MWe) of Rajasthan Atomic Power Station, one reactor of which is already operational. Some guidance and tables for selection of grout for a specific use have also been given. (auth.)

  9. Rock grouting. Current competence and development for the final repository

    International Nuclear Information System (INIS)

    Emmelin, Ann; Brantberger, Martin; Eriksson, Magnus; Gustafson, Gunnar; St ille, Haakan

    2007-06-01

    The report aims at presenting the overall state of grouting competence and development relating to the final repository and at motivating and giving detail to the grouting sections presented in the 2007 version of the overall SKB report 'Programme for research, development and demonstration of methods for the management and disposal of nuclear waste' that is presented to the government every three years. The report offers suggestions for principles for planning, design and execution of grouting and describes the further work thought to be necessary in order to meet the requirements of the final repository, that are currently given as working premises. This report does not aim to, and cannot, describe the grouting processes in detail. For details of current concepts, experience and development work, a list of references is provided. In Chapter 2, the task of sealing the underground repository is examined and an overall approach presented. Although the requirements related to this task are preliminary, it is made evident that they concern both the actual grouting results and the process leading to the achievement of these results. Chapter 3 is a conceptual description of grouting and the factors that govern the spreading of grout in the rock mass. It is intended as an introduction to Chapters 4-6, which describe the state of grouting competence and the tools available for the sealing of the final repository facility. Both common practice and cutting-edge research are dealt with in these chapters, mainly relying on references where available. Chapters 4 and 5 focus on the system consisting of the fundamental components the rock mass, the grout materials and the grouting technology, and how these system components interact whilst, in Chapter 6, the rock/grout technical system is viewed in a brief organizational context. Based on the requirements on results and the overall grouting process on the one hand and the current competence in grouting theory and practice on the

  10. Rock grouting. Current competence and development for the final repository

    Energy Technology Data Exchange (ETDEWEB)

    Emmelin, Ann (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Brantberger, Martin (Ramboell (SE)); Eriksson, Magnus (Vattenfall Power Consultant (SE)); Gustafson, Gunnar (Chalmers Univ. of Technology, Goeteborg (SE)); Stille, Haakan (Royal Inst. of Technology, Stockholm (SE))

    2007-06-15

    The report aims at presenting the overall state of grouting competence and development relating to the final repository and at motivating and giving detail to the grouting sections presented in the 2007 version of the overall SKB report 'Programme for research, development and demonstration of methods for the management and disposal of nuclear waste' that is presented to the government every three years. The report offers suggestions for principles for planning, design and execution of grouting and describes the further work thought to be necessary in order to meet the requirements of the final repository, that are currently given as working premises. This report does not aim to, and cannot, describe the grouting processes in detail. For details of current concepts, experience and development work, a list of references is provided. In Chapter 2, the task of sealing the underground repository is examined and an overall approach presented. Although the requirements related to this task are preliminary, it is made evident that they concern both the actual grouting results and the process leading to the achievement of these results. Chapter 3 is a conceptual description of grouting and the factors that govern the spreading of grout in the rock mass. It is intended as an introduction to Chapters 4-6, which describe the state of grouting competence and the tools available for the sealing of the final repository facility. Both common practice and cutting-edge research are dealt with in these chapters, mainly relying on references where available. Chapters 4 and 5 focus on the system consisting of the fundamental components the rock mass, the grout materials and the grouting technology, and how these system components interact whilst, in Chapter 6, the rock/grout technical system is viewed in a brief organizational context. Based on the requirements on results and the overall grouting process on the one hand and the current competence in grouting theory and

  11. Characterization of a low-level radioactive waste grout: Sampling and test results

    International Nuclear Information System (INIS)

    Martin, P.F.C.; Lokken, R.O.

    1992-12-01

    WHC manages and operates the grout treatment facility at Hanford as part of a DOE program to clean up wastes stored at federal nuclear production sites. PNL provides support to the grout disposal program through pilot-scale tests, performance assessments, and formulation verification activities. in 1988 and 1989, over one million gallons of a low-level radioactive liquid waste was processed through the facility to produce a grout waste that was then deposited in an underground vault. The liquid waste was phosphate/sulfate waste (PSW) generated in decontamination of the N Reactor. PNL sampled and tested the grout produced during the second half of the PSW campaign to support quality verification activities prior to grout vault closure. Samples of grout were obtained by inserting nested-tube samplers into the grout slurry in the vault. After the grout had cured, the inner tube of the sampler was removed and the grout samples extracted. Tests for compressive strength, sonic velocity, and leach testing were used to assess grout quality; results were compared to those from pilot-scale test grouts made with a simulated PSW. The grout produced during the second half of the PSW campaign exceeded compressive strength and leachability formulation criteria. The nested tube samplers were effective in collecting samples of grout although their use introduced greater variability into the compressive strength data

  12. Leach behavior of hydrofracture grout incorporating radioactive wastes

    International Nuclear Information System (INIS)

    Moore, J.G.; Godbee, H.W.; Kibbey, A.H.

    1976-01-01

    Rates at which Sr, Cs, Pu, and Cm are leached from hydrofracture grout were measured. The fraction of an isotope leached varied with the square root of time if the leachant was replaced more frequently than once per day, but was inhibited or depressed if replacement was made less often. The amount of Sr or Cs leached from the grout varied directly with the degree of drying during curing and inversely with the time of curing. Of the clay additives studied for enhancing cesium retention, Grundite, while satisfactory, was the least effective. In general, the isotope leach rate followed the order: Cs greater than Sr greater than Cm greater than Pu. The amount leached as a function of the leachant varied in the order: distilled water greater than tap water greater than grout water. Concentrating the waste by a factor of up to 4 before grouting had little effect on the leach rate. Comparison with results for other products indicates that the grout can provide leach rates comparable to those for wastes incorporated into borosilicate glass. Theoretical relationships that consider diffusion and instantaneous reaction (an equilibrium or time-dependent relationship between mobile and immobile forms of a species) were in good agreement with the data for the 28-day-cured grout when the leachant was initially replaced twice per day. The credibility of laboratory results with simulated waste was substantiated by a short-term continuous leach test made on a fragment of a core sample of actual hydrofracture grout. The modified effective diffusivities (10 -11 to 10 -10 cm 2 /s, equivalent to a leach rate of the order of 10 -7 g cm -2 day -1 ) for Sr and Cs calculated from these data are comparable to laboratory values. 17 figures, 5 tables

  13. Cement based grouts - longevity laboratory studies: leaching behaviour

    International Nuclear Information System (INIS)

    Onofrei, M.; Gray, M.; Roe, L.

    1991-12-01

    This report describes a series of laboratory tests carried out to determine the possible leaching behaviour of cement-based grouts in repository environments. A reference high-performance cement-based grout, comprised of Canadian Type 50 (U.S. Type V) Sulphate Resisting Portland Cement, silica fume, potable water and superplasticizer, and a commercially available cement grout were subjected to leaching in distilled water and three simulated groundwaters of different ionic strength. Hardened, monolithic specimens of the grout were leached in static, pulsed-flow and continuous flow conditions at temperatures from 10 degrees C to 150 degrees C for periods of up to 56 days. The changes in concentration of ions in the leachants with time were determined and the changes in the morphology of the surfaces of the grout specimens were examined using electron microscopy. After a review of possible mechanisms of degradation of cement-based materials, the data from these experiments are presented. The data show that the grouts will leach when in contact with water through dissolution of more soluble phases. Comparison of the leaching performance of the two grouts indicates that, while there are some minor differences, they behaved quite similarly. The rate of the leaching processes were found to tend to decrease with time and to be accompanied by precipitation and/or growth of an assemblage of secondary alteration phases (i.e., CaCO 3 , Mg(OH) 2 ). The mechanisms of leaching depended on the environmental conditions of temperature, groundwater composition and water flow rate. Matrix dissolution occurred. However, in many of the tests leaching was shown to be limited by the precipitated/reaction layers which acted as protective surface coatings. (37 refs.) (au)

  14. Preliminary assessment of a 'surface fusible grout' concept

    International Nuclear Information System (INIS)

    Sellars, B.G.

    1992-03-01

    The Canadian Fusion Fuels Technology Project is evaluating the uptake and release of tritium (DT, T 2 ), tritiated hydrogen (HT) and tritiated water (HTO) by building materials to be used in fusion reactor enclosures. Concrete will be an important building material and poses a special problem because of its porous microstructure and the chemical makeup of the material. One approach to reducing the uptake of HT and HTO into concrete is to apply a permeation barrier directly onto the concrete. Glazed ceramic tiles are one barrier with low HT and HTO uptake; however, the grouting between tiles is a major concern. It would be desirable to seal the grout with a glassy permeation barrier. The concept investigated in this program is based on plasma spraying: injecting a powder into a high velocity flame to melt the powder particles and project them towards a target substrate. Glass on the substrate is then to be fused by the plasma flame while a molten glass is deposited on top. Ceramic bonded grouts were developed based on fused silica or borosilicate powders and ethyl silicate or sodium silicate air-set binders. Sodium silicate grouts exhibit lower porosity after drying than ethyl silicate-based grouts, although both are porous. Careful control of the ratio of coarse to fine powder fractions is necessary to minimize or eliminate drying shrinkage. The surface of grouts based on borosilicate glass could not be fused without cracking of neighbouring tiles. When a porcelain enamel glass was plasma spray deposited and fused onto the surface of a grout line and adjacent tiles crazing was observed upon dye penetrant testing

  15. In situ preparation of CuS cathode with unique stability and high rate performance for lithium ion batteries

    International Nuclear Information System (INIS)

    Wang Yourong; Zhang Xianwang; Chen Peng; Liao Hantao; Cheng Siqing

    2012-01-01

    A simple approach, for the first time, was presented for in situ preparation of the CuS cathode. The obtained CuS cathodes were investigated by the measurements of X-ray diffraction pattern, scanning electronic microscopy, and electrochemical performance. The results indicate the CuS cathodes are composed of plenty of nano flakes, which construct a large 3-D net structure. Moreover, the CuS cathodes exhibit reversible capacity of 447.4, 414.1, 389.9 and 376.0 mAh g −1 at 0.2 C, 0.5 C, 1 C and 2 C respectively and excellent cycle stability for more than 100 cycles. The possible mechanism of the unique stability of the CuS cathode was discussed.

  16. Thermal stability and in situ SiN passivation of InAlN/GaN high electron mobility heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Lugani, L.; Carlin, J.-F.; Py, M. A.; Grandjean, N. [ICMP, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2014-09-15

    We investigate the thermal stability of nearly lattice-matched InAlN layers under metal organic vapor phase epitaxy conditions for temperatures >800 °C and show that they are not fully stable. In particular, InAlN top layers undergo degradation during high temperature annealing due to a surface related process, which causes the loss of crystal quality. This strongly impacts the transport properties of InAlN/GaN HEMT heterostructures; in particular, the mobility is significantly reduced. However, we demonstrate that high thermal stability can be achieved by capping with a GaN layer as thin as 0.5 nm. Those findings enabled us to realize in situ passivated HEMT heterostructures with state of the art transport properties.

  17. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1988-01-01

    This section briefly describes the Hanford Site, provides a general description of the site operations and administration, provides an overview of the contents of this Grout Treatment Facility (GTF) Permit Application, and gives a list of acronyms and abbreviations used in the document. The decision was made to use the checklist as a locator reference instead of using the checklist section numbers as paragraph section numbers because several different types of waste management units, some of which are not addressed in the checklists, are part of the GTF. The GTF is a waste management unit within the Hanford Site facility. In May 1988, permit application was filed that identified the GTF as an existing facility. The GTF mixes dry cementitious solids with liquid mixed wastes (containing both dangerous and radioactive constituents) produced by Hanford Site operations. In addition to the design and operating features of the GTF that are intended to meet the requirements of dangerous waste regulations, many additional design and operating features are necessary to comply with radioactive waste management practices. The GTF design features and practices are intended to keep operational exposure to radionuclides and dangerous substances ''as low as reasonably achievable'' (ALARA) and to provide a disposal system that protects the environment for at least 10,000 yr. In some instances, ALARA practices present difficulties when complying with requirements of dangerous waste regulations

  18. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1988-01-01

    This section briefly describes the Hanford Site, provides a general description of the site operations and administration, provides an overview of the contents of this Grout Treatment Facility (GTF) Permit Application, and gives a list of acronyms and abbreviations used in the document. The decision was made to use the checklist as a locator reference instead of using the checklist section numbers as paragraph section numbers because several different types of waste management units, some of which are not addressed in the checklists, are part of the GTF. The GTF is a waste management unit within the Hanford Site facility. In May 1988, a permit application was filed that identified the GTF as an existing facility. The GTF mixes dry cementitious solids with liquid mixed wastes (containing both dangerous and radioactive constituents) produced by Hanford Site operations. In addition to the design and operating features of the GTF that are intended to meet the requirements of dangerous waste regulations, many additional design and operating features are necessary to comply with radioactive waste management practices. The GTF design features and practices are intended to keep operational exposure to radionuclides and dangerous substances ''as low as reasonably achievable'' (ALARA) and to provide a disposal system that protects the environment for at least 10,000 yr. In some instances, ALARA practices present difficulties when complying with requirements of dangerous waste regulations. This volume contains 2 appendices covering engineering drawings and operating procedures

  19. Mechanisms of contaminant migration from grouted waste

    International Nuclear Information System (INIS)

    Magnuson, S.O.; Yu, A.D.

    1992-01-01

    Low-level radioactive decontaminated salt solution is generated at the Savannah River Site (SRS) from the In-Tank Precipitation process. The solution is mixed with cement, slag, and fly ash, to form a grout, termed ''Saltstone'', that will be disposed in concrete vaults at the Saltstone Disposal Facility (SDF) [1]. Of the contaminants in the Saltstone, the greatest concern to SRS is the potential release of nitrate to the groundwater because of the high initial nitrate concentration (0.25 g/cm 3 ) in the Saltstone and the low Safe Drinking Water Act (SDWA) maximum contaminant level (MCL) of 44 mg/L. The SDF is designed to allow a slow, controlled release over thousands of years. This paper addresses a modeling study of nitrate migration from intact non-degraded concrete vaults in the unsaturated zone for the Radiological Performance Assessment (PA) of the SRS Saltstone Disposal Facility [3]. The PA addresses the performance requirements mandated by DOE Order 5820.2A [4

  20. Grout treatment facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1988-01-01

    This section briefly describes the Hanford Site, provides a general description of the site operations and administration, provides an overview of the contents of this Grout Treatment Facility (GTF) Permit Application, and gives a list of acronyms and abbreviations used in the document. The decision was made to use the checklist as a locator reference instead of using the checklist section numbers as paragraph section numbers because several different types of waste management units, some of which are not addressed in the checklists, are part of the GTF. The GTF is a waste management unit within the Hanford Site facility. In May 1988, a permit application was filed that identified the GTF as an existing facility. The GTF mixes dry cementitious solids with liquid mixed wastes (containing both dangerous and radioactive constitutents) produced by Hanford Site operations. In addition to the design and operating features of the GTF that are intended to meet the requirements of dangerous waste regulations, many additional design and operating features are necessary to comply with radioactive waste management practices. The GTF design features and practices are intended to keep operational exposure to radionuclides and dangerous substances ''as low as reasonably achievable'' (ALARA) and to provide a disposal system that protects the environment for at least 10,000 yr. In some instances, ALARA practices present difficulties when complying with requirements of dangerous waste regulations. This volume contains 2 Appendices covering engineering drawings and operating procedures

  1. Grout Treatment Facility dangerous waste permit application

    International Nuclear Information System (INIS)

    1988-01-01

    This section briefly describes the Hanford Site, provides a general description of the site operations and administration, provides an overview of the contents of this Grout Treatment Facility (GTF) Permit Application, and gives a list of acronyms and abbreviations used in the document. The decision was made to use the checklist as a locator reference instead of using the checklist section numbers as paragraph section numbers because several different types of waste management units, some of which are not addressed in the checklists, are part of the GTF. The GTF is a waste management unit within the Hanford Site facility. In May 1988, a permit application was filed that identified the GTF as an existing facility. The GTF mixes dry cementitious solids with liquid wastes (containing both dangerous and radioactive constituents) produced by Hanford Site operations. In addition to the design and operating features of the GTF that are intended to meet the requirements of dangerous waste regulations, many additional design and operating features are necessary to comply with radioactive waste management practices. The GTF design features and practices are intended to keep operational exposure to radionuclides and dangerous substances ''as low as reasonably achievable'' (ALARA) and to provide a disposal system that protects the environment for at least 10,000 yr. In some instances, ALARA practices present difficulties when complying with requirements of dangerous waste regulations. This volume contains 14 Appendices. Topics include Engineering Drawings, Maps, Roads, Toxicity Testing, and Pilot-Scale Testing

  2. Theoretical stability assessment of uranyl phosphates and apatites: Selection of amendments for in situ remediation of uranium

    International Nuclear Information System (INIS)

    Raicevic, S.; Wright, J.V.; Veljkovic, V.; Conca, J.L.

    2006-01-01

    Addition of an amendment or reagent to soil/sediment is a technique that can decrease mobility and reduce bioavailability of uranium (U) and other heavy metals in the contaminated site. According to data from literature and results obtained in field studies, the general mineral class of apatites was selected as a most promising amendment for in situ immobilization/remediation of U. In this work we presented theoretical assessment of stability of U(VI) in four apatite systems (hydroxyapatite (HAP), North Carolina Apatite (NCA), Lisina Apatite (LA), and Apatite II) in order to determine an optimal apatite soil amendment which could be used for in situ remediation of uranium. In this analysis we used a theoretical criterion which is based on calculation of the ion-ion interaction potential, representing the main term of the cohesive energy of the matrix/pollutant system. The presented results of this analysis indicate (i) that the mechanism of immobilization of U by natural apatites depends on their chemical composition and (ii) that all analyzed apatites represent, from the point of view of stability, promising materials which could be used in field remediation of U-contaminated sites

  3. Solubility of krypton in hydrofracture grout at elevated pressures

    International Nuclear Information System (INIS)

    Fitzgerald, C.L.; Mailen, J.C.

    1982-01-01

    The solubilities of krypton in water, simulated waste solution, and simulated grout at about 25 0 C and to pressures of 150 atm have been determined. The results of these studies show that preliminary calculations of krypton solubility based on the aqueous component of the hydrofracture grout were overly pessimistic. The volume of noble gas generated annually by the reference reprocessing plant would be soluble in the annual hydrofracture grout injection at ORNL at about 10 atm. The amount of krypton in the gas phase would depend on the amount of air in the hydrofracture grout mixture. At 34 atm, and with a small air volume relative to the injected krypton, the krypton would constitute about 30% of the gas bubbles. The disposal of krypton via injection with hydrofracture grout seems to be a viable process. The next logical steps would be to determine the krypton diffusion rate at injection conditions, and possibly to perform a test injection. At present, the schedule for future work is uncertain since funds for this project have been reduced significantly

  4. The use of cement grouts for the immobilisation of solid radioactive waste

    International Nuclear Information System (INIS)

    Brown, D.J.; Smith, D.L.

    1982-06-01

    The use of cement grouts is being considered for the immobilisation of solid items of radioactive waste. In this report the factors which influence the selection of a grout for use in an active plant are identified. The properties and limitations of standard cement grouts are summarised. Inactive grouting trials carried out in the period September 1981 to June 1982 on the 220 dm 3 scale are described. (author)

  5. Development of an in-line grout meter for improved quality control

    International Nuclear Information System (INIS)

    Del Cul, G.D.; Gilliam, T.M.

    1991-05-01

    This report documents progress to date on the development of an in-line grout meter and demonstration of its applicability at operating temperature of 50 degree C. The grout meter, which is based on measurement of grout electrical resistance/capacitance, is intended to provide real-time measurements of grout mix ratio (ratio of dry-solids-blend materials to waste). 4 refs., 6 figs., 5 tabs

  6. Protection against water or mud inrush in tunnels by grouting: A review

    Directory of Open Access Journals (Sweden)

    Shucai Li

    2016-10-01

    Full Text Available Grouting is a major method used to prevent water and mud inrush in tunnels and underground engineering. In this paper, the current situation of control and prevention of water and mud inrush is summarized and recent advances in relevant theories, grout/equipment, and critical techniques are introduced. The time-variant equations of grout viscosity at different volumetric ratios were obtained based on the constitutive relation of typical fast curing grouts. A large-scale dynamic grouting model testing system (4000 mm × 2000 mm × 5 mm was developed, and the diffusions of cement and fast curing grouts in dynamic water grouting were investigated. The results reveal that the diffusions of cement grouts and fast curing grouts are U-shaped and asymmetric elliptical, respectively. A multi-parameter real-time monitoring system (ϕ = 1.5 m, h = 1.2 m was developed for the grouting process to study the diffusion and reinforcement mechanism of grouting in water-rich faulted zone. A high early strength cream-type reinforcing/plugging grout, a high permeability nano-scale silica gel grout, and a high-expansion filling grout were proposed for the control of water hazards in weak water-rich faulted zone rocks, water inrush in karst passages, and micro-crack water inrush, respectively. Complement technologies and equipment for industrial applications were also proposed. Additionally, a novel full-life periodic dynamic water grouting with the critical grouting borehole as the core was proposed. The key techniques for the control of water inrush in water-rich faulted zone, jointed fissures and karst passages, and micro-crack water inrush were developed.

  7. Experimental Characterization of Stress- and Strain-Dependent Stiffness in Grouted Rock Masses

    Directory of Open Access Journals (Sweden)

    Ji-Won Kim

    2018-03-01

    Full Text Available Grouting of fractured rock mass prior to excavation results in grout-filled discontinuities that govern the deformation characteristics of a site. The influence of joint characteristics on the properties of grouted rocks is important in assessing the effects of grouting on jointed rock mass. However, grouting remains a predominantly empirical practice and the effects of grouting on rock joint behavior and material properties have yet to be accurately assessed. Granular materials, including jointed rocks, typically display nonlinear strain-dependent responses that can be characterized by the shear modulus degradation curve. In this study, the effects of grouting on the strain-dependent shear stiffness of jointed rock mass were investigated at the small-strain (below 10−5 and mid-strain (10−5 to 10−3 ranges using the quasi-static resonant column test and rock mass dynamic test devices. The effects of curing time, axial stress, initial joint roughness, and grouted joint thickness were examined. The results show that (1 grouting of rock joints leads to decreased stress sensitivity and increased small-strain shear stiffness for all tested samples; (2 the grouted rock samples display similar modulus degradation characteristics as the applied grout material; (3 the initial joint roughness determines the stress-dependent behaviors and general stiffness range of the jointed and grouted rocks, but the strain-dependent behaviors are dependent on the properties of the grout material; (4 increased grouted joint thickness results in larger contribution of the grout properties in the overall grouted rock mass.

  8. Systematic approach for the design of pumpable cement-based grouts for immobilization of hazardous wastes

    International Nuclear Information System (INIS)

    Sams, T.L.; Gilliam, T.M.

    1987-01-01

    Cement-based grouts have been proven to be an economical and environmentally acceptable means of waste disposal. Costs can be reduced if the grout is pumped to the disposal site. This paper presents a systematic approach to guide the development of pumpable grouts. 20 refs., 2 figs

  9. Liquid return from gas pressurization of grouted waste

    International Nuclear Information System (INIS)

    Powell, W.J.; Benny, H.L.

    1994-05-01

    The ability to force pore liquids out of a simulated waste grout matrix using air pressure was measured. Specimens cured under various conditions were placed in a permeameter and subjected to increasing air pressure. The pressure was held constant for 24 hours and then stepped up until either liquid was released or 150 psi was reached. One specimen was taken to 190 psi with no liquid release. Permeability to simulated tank waste was then measured. Compressive strength was measured following these tests. This data is to assess the amount of fluid that might be released from grouted waste resulting from the buildup of radiolytically generated hydrogen and other gasses within the waste form matrix. A plot of the unconfined compressive strength versus breakthrough pressures identifies a region of ''good'' grout, which will resist liquid release

  10. Performance of Grouted Splice Sleeve Connector under Tensile Load

    Directory of Open Access Journals (Sweden)

    A. Alias

    2016-05-01

    Full Text Available The grouted splice sleeve connector system takes advantage of the bond-slip resistance of the grout and the mechanical gripping of reinforcement bars to provide resistance to tensile force. In this system, grout acts as a load-transferring medium and bonding material between the bars and sleeve. This study adopted the end-to-end rebars connection method to investigate the effect of development length and sleeve diameter on the bonding performance of the sleeve connector. The end-to-end method refers to the condition where reinforcement bars are inserted into the sleeve from both ends and meet at the centre before grout is filled. Eight specimens of grouted splice sleeve connector were tested under tensile load to determine their performance. The sleeve connector was designed using 5 mm thick circular hollow section (CHS steel pipe and consisted of one external and two internal sleeves. The tensile test results show that connectors with a smaller external and internal sleeve diameter appear to provide better bonding performance. Three types of failure were observed in this research, which are bar fracture (outside the sleeve, bar pullout, and internal sleeve pullout. With reference to these failure types, the development length of 200 mm is the optimum value due to its bar fracture type, which indicates that the tensile capacity of the connector is higher than the reinforcement bar. It is found that the performance of the grouted splice sleeve connector is influenced by the development length of the reinforcement bar and the diameter of the sleeve.

  11. Pullout Performances of Grouted Rockbolt Systems with Bond Defects

    Science.gov (United States)

    Xu, Chang; Li, Zihan; Wang, Shanyong; Wang, Shuren; Fu, Lei; Tang, Chunan

    2018-03-01

    This paper presents a numerical study on the pullout behaviour of fully grouted rockbolts with bond defects. The cohesive zone model (CZM) is adopted to model the bond-slip behaviour between the rockbolt and grout material. Tensile tests were also conducted to validate the numerical model. The results indicate that the defect length can obviously influence the load and stress distributions along the rockbolt as well as the load-displacement response of the grouted system. Moreover, a plateau in the stress distribution forms due to the bond defect. The linear limit and peak load of the load-displacement response decrease as the defect length increases. A bond defect located closer to the loaded end leads to a longer nonlinear stage in the load-displacement response. However, the peak loads measured from the specimens made with various defect locations are almost approximately the same. The peak load for a specimen with the defects equally spaced along the bolt is higher than that for a specimen with defects concentrated in a certain zone, even with the same total defect length. Therefore, the dispersed pattern of bond defects would be much safer than the concentrated pattern. For the specimen with dispersed defects, the peak load increases with an increase in the defect spacing, even if the total defect length is the same. The peak load for a grouted rockbolt system with defects increases with an increases in the bolt diameter. This work leads to a better understanding of the load transfer mechanism for grouted rockbolt systems with bond defects, and paves the way towards developing a general evaluation method for damaged rockbolt grouted systems.

  12. Stability of gas atomized reactive powders through multiple step in-situ passivation

    Science.gov (United States)

    Anderson, Iver E.; Steinmetz, Andrew D.; Byrd, David J.

    2017-05-16

    A method for gas atomization of oxygen-reactive reactive metals and alloys wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a protective reaction film on the atomized particles. The present invention is especially useful for making highly pyrophoric reactive metal or alloy atomized powders, such as atomized magnesium and magnesium alloy powders. The gaseous reactive species (agents) are introduced into the atomization spray chamber at locations downstream of a gas atomizing nozzle as determined by the desired powder or particle temperature for the reactions and the desired thickness of the reaction film.

  13. Stability of Porous Platinum Nanoparticles: Combined In Situ TEM and Theoretical Study

    DEFF Research Database (Denmark)

    Chang, Shery L. Y.; Barnard, Amanda S.; Dwyer, Christian

    2012-01-01

    Porous platinum nanoparticles provide a route for the development of catalysts that use less platinum without sacrificing catalytic performance. Here, we examine porous platinum nanoparticles using a combination of in situ transmission electron microscopy and calculations based on a first-principles......-parametrized thermodynamic model. Our experimental observations show that the initially irregular morphologies of the as-sythesized porous nanoparticles undergo changes at high temperatures to morphologies having faceted external surfaces with voids present in the interior of the particles. The increasing size of stable...

  14. Injection grout for deep repositories. Subproject 1: LowpH cementitious grout for larger fractures, leach testing of grout mixes and evaluation of the long-term safety

    International Nuclear Information System (INIS)

    Vuorinen, U.; Lehikoinen, J.; Imoto, Harutake; Yamamoto, Takeshi; Cruz Alonso, M.

    2005-10-01

    Constructing an underground disposal facility for spent nuclear fuel deep in bedrock requires lowpH cement-based injection grout, because assured data of the extent of a possible high-pH plume in saturated bedrock conditions is lacking. In this work low-pH grout mixes of new design were subjected to leach testing. Before chosen to leach testing the grout mixes had to fulfil certain technical requirements. Leach testing was performed in order to establish that the pH requirement (≤11) set for the leachates was met. For comparison reasons also one conventionally used cement based grout material was included in the tests. Two kinds of lowpH grout cement mixes were tested; mixes with added blast furnace slag (4 mixes) or added silica (6 mixes). All the mixes were not completely tested according to the test plan, because for some mixes during leach testing factors detrimental to the long-term safety of a repository were observed, e.g. too high pH or leached sulphide, which is harmful for copper. Leach testing of the grout mixes was performed in a glove-box (N 2 atmosphere) in order to avoid the interference of atmospheric CO 2 on the alkaline leachates. Two simulated groundwater solutions, saline OL-SO and fresh ALL-MR, were used as leachates. Two leach tests were applied; equilibrium and diffusion tests. In the equilibrium test at each measuring point only a part of the leachate was exchanged, whereas in the diffusion test the entire leachate was exchanged. The pH value of each leachate sample was measured, but total alkalinity was determined only for some leachates. Na, K, Ca, Mg, Al, Fe, Si, SO 4 2- , S TOT , and Cl were analysed in the leach solutions collected in the diffusion test of four grout mixes chosen. Also the corresponding solid specimens were analysed (SEM, XRD, EPMA, MIP, TG) in Japan. A few grout pore fluid pH values were measured in Spain, as well. The simplified thermodynamic model calculations were successful in qualitatively reproducing the

  15. Clinical application for the preservation of phospho-proteins through in-situ tissue stabilization

    Directory of Open Access Journals (Sweden)

    Ding Wei

    2010-11-01

    Full Text Available Abstract Background Protein biomarkers will play a pivotal role in the future of personalized medicine for both diagnosis and treatment decision-making. While the results of several pre-clinical and small-scale clinical studies have demonstrated the value of protein biomarkers, there have been significant challenges to translating these findings into routine clinical care. Challenges to the use of protein biomarkers include inter-sample variability introduced by differences in post-collection handling and ex vivo degradation of proteins and protein modifications. Results In this report, we re-create laboratory and clinical scenarios for sample collection and test the utility of a new tissue stabilization technique in preserving proteins and protein modifications. In the laboratory setting, tissue stabilization with the Denator Stabilizor T1 resulted in a significantly higher yield of phospho-protein when compared to standard snap freeze preservation. Furthermore, in a clinical scenario, tissue stabilization at collection resulted in a higher yield of total phospho-protein, total phospho-tyrosine, pErkT202/Y204 and pAktS473 when compared to standard methods. Tissue stabilization did not have a significant effect on other post-translational modifications such as acetylation and glycosylation, which are more stable ex-vivo. Tissue stabilization did decrease total RNA quantity and quality. Conclusion Stabilization at the time of collection offers the potential to better preserve tissue protein and protein modification levels, as well as reduce the variability related to tissue processing delays that are often associated with clinical samples.

  16. Polluted soils with heavy metals. Stabilization by magnesium oxide. Ex-situ and in-situ testings; Suelos contaminados con metales pesados. Estabilizacion con oxido de magnesio. Ensayos ex situ-in situ

    Energy Technology Data Exchange (ETDEWEB)

    Cenoz, S.; Hernandez, J.; Gangutia, N.

    2004-07-01

    This work describes the use of Low-Grade MgO as a stabiliser agent for polluted soil reclaim. Low-Grade MgO may be an economically feasible alternative in the stabilisation of heavy metals from heavily contaminated soils. The effectiveness of Low-Grade MgO has been studied in three ex-situ stabilisation of heavily polluted soils contaminated by the flue-dust of pyrite roasting. LG-MgO provides an alkali reservoir guaranteeing long-term stabilisation without varying the pH conditions. The success of the ex-situ stabilisation was corroborated with the analysis of heavy metals in the leachates collected from the landfill o ver a long period of time. The study also includes the results obtained in an in-situ pilot scale stabilisation of contaminated soil. (Author) 17 refs.

  17. Contemporary drilling and grouting practices for dam remediation

    International Nuclear Information System (INIS)

    Bruce, D.A.; Naudts, A.

    1998-01-01

    A generic classification for the different methods used in rock drilling and overburden drilling is described, along with a classification of the range of grouting materials available and the different grouting methods that can be used. Examples are presented from two recent major dam remediation projects to demonstrate the basis for selection and use of the different methods and materials. It was shown that a high level of performance can be obtained when a project is properly designed, executed and monitored. 29 refs., 5 tabs., 5 figs

  18. A dynamic simulation of the Hanford site grout facility

    International Nuclear Information System (INIS)

    Zimmerman, B.D.; Klimper, S.C.; Williamson, G.F.

    1992-01-01

    Computer-based dynamic simulation can be a powerful, low-cost tool for investigating questions concerning timing, throughput capability, and ability of engineering facilities and systems to meet established milestones. The simulation project described herein was undertaken to develop a dynamic simulation model of the Hanford site grout facility and its associated systems at the US Department of Energy's (DOE's) Hanford site in Washington State. The model allows assessment of the effects of engineering design and operation trade-offs and of variable programmatic constraints, such as regulatory review, on the ability of the grout system to meet milestones established by DOE for low-level waste disposal

  19. Experimental study of cement grout : Rheological behavior and sedimentation

    OpenAIRE

    ROSQUOET, F; ALEXIS, A; KHELIDJ, A; PHELIPOT, A

    2003-01-01

    Three basic elements (cement, water and admixture) usually make up injectable cement grouts used for prestressed cable coating, repair and consolidation of masonry, soil grouting, etc. The present study was divided into two parts. First, in order to characterize rheologically fresh cement paste with water/cement ratios (W/C) varying between 0,35 and 1, an expeirmental study was carried out and has revealed that the cement past behaves like a shear-thinning material, whatever is the W/C ratio....

  20. In situ formation of magnetite reactive barriers in soil for waste stabilization

    Science.gov (United States)

    Moore, Robert C.

    2003-01-01

    Reactive barriers containing magnetite and methods for making magnetite reactive barriers in situ in soil for sequestering soil contaminants including actinides and heavy metals, organic materials, iodine and technetium are disclosed. According to one embodiment, a two-step reagent introduction into soil takes place. In the first step, free oxygen is removed from the soil by separately injecting into the soil aqueous solutions of iron (II) salt, for example FeCl.sub.2, and base, for example NaOH or NH.sub.3 in about a 1:1 volume ratio. Then, in the second step, similar reagents are injected a second time (however, according to about a 1:2 volume ratio, iron to salt) to form magnetite. The magnetite formation is facilitated, in part, due to slow intrusion of oxygen into the soil from the surface. The invention techniques are suited to injection of reagents into soil in proximity to a contamination plume or source allowing in situ formation of the reactive barrier at the location of waste or hazardous material. Mixing of reagents to form. precipitate is mediated and enhanced through movement of reagents in soil as a result of phenomena including capillary action, movement of groundwater, soil washing and reagent injection pressure.

  1. Stabilization and in situ management of radioactive contaminated sediments of Port Hope harbor

    International Nuclear Information System (INIS)

    Dolinar, G.M.; Killey, R.W.D.; Philipase, K.E.

    1991-01-01

    This paper presents the findings of laboratory and field studies undertaken to assess the feasibility of in situ management of contaminated sediments in Port Hope harbor. The contaminated sediments stem from historic releases from an adjacent radium and uranium refinery, and uranium, arsenic, and radium are the most abundant contaminants. With improved emission controls, currently accumulating sediments have much lower levels of contamination, and the harbor waters currently meet water quality limits for the contaminants of concern. Within a few years, however, the continuing sedimentation will render the harbor unusable. Field tests have confirmed the dredging will result in incomplete removal of the contaminated sediments and that sediment suspension and the release of pores waters during dredging will produce harbor water contaminant concentrations that would require the treatment of large volumes of water. In addition, no remedial work can start until a site for the dredged material can be found. The local community inquired whether in situ burial of the sediments and abandonment of the harbor would provide safe disposal

  2. In Situ Stability of Substrate-Associated Cellulases Studied by DSC

    DEFF Research Database (Denmark)

    Borch, Kim; Cruys-Bagger, Nicolaj; Badino, Silke Flindt

    2014-01-01

    This work shows that differential scanning calorimetry (DSC) can be used to monitor the stability of substrate-adsorbed cellulases during long-term hydrolysis of insoluble cellulose. Thermal transitions of adsorbed enzyme were measured regularly in subsets of a progressing hydrolysis, and the size...

  3. In situ stabilizer formation from methacrylic acid macromonomers in emulsion polymerization

    NARCIS (Netherlands)

    Schreur-Piet, Ingeborg; Heuts, Johan P.A.

    2017-01-01

    Oligomers of methacrylic acid containing a propenyl ω-endgroup (i.e. MAA-macromonomers) were synthesized by cobalt-mediated catalytic chain transfer polymerization and used as precursors to stabilizers in emulsion polymerization. It was found that only in those polymerizations in which these

  4. Study on the mechanism of seepage flow in the grouting for multiple fractured model

    International Nuclear Information System (INIS)

    Nishigaki, Makoto; Mikake, Shin-ichiro

    2002-01-01

    The purpose of study is to improve the grouting method for fractured rock masses. In this paper, the results on the fundamental phenomenon for grasping the properties of grouting injection and seepage flow are discussed. The case of grouting stage is studied about the multiple hydraulic fractured apertures in the injected borehole. So the theory on the mechanism is constructed, and experiment is executed in order to verify the availability of the theory. From the results, it is shown that Bernoulli's law is able to prove the behavior of the grouting. And the theoretical evaluation is executed on the experiential procedure of the grouting. (author)

  5. Kinetically controlled fabrication of gold nanorods and investigation of their thermal stability via in-situ TEM heating

    Science.gov (United States)

    Chankhunthod, N.; Aslam, Z.; Critchley, K.; Evans, S. D.; Brydson, R.

    2017-09-01

    Size controlled CTAB-capped AuNRs with various aspect ratios (ARs) ranging from 1.63±0.13 to 4.12±0.25 were synthesized following a modified seed-mediated method. Their thermal stability was examined by in-situ TEM heating. The results revealed a structural change from rods to spheres with increasing temperature. At lower temperatures 600ºC, particles became increasingly spherical. This behaviour occurred at temperatures lower than the melting point of bulk gold supporting a surface diffusion mechanism with material diffusing from the tips and redepositing at the middle of the rods. The rate of change in AR appeared to increase for thinner AuNRs.

  6. In Situ Local Measurement of Austenite Mechanical Stability and Transformation Behavior in Third-Generation Advanced High-Strength Steels

    Science.gov (United States)

    Abu-Farha, Fadi; Hu, Xiaohua; Sun, Xin; Ren, Yang; Hector, Louis G.; Thomas, Grant; Brown, Tyson W.

    2018-05-01

    Austenite mechanical stability, i.e., retained austenite volume fraction (RAVF) variation with strain, and transformation behavior were investigated for two third-generation advanced high-strength steels (3GAHSS) under quasi-static uniaxial tension: a 1200 grade, two-phase medium Mn (10 wt pct) TRIP steel, and a 980 grade, three-phase TRIP steel produced with a quenching and partitioning heat treatment. The medium Mn (10 wt pct) TRIP steel deforms inhomogeneously via propagative instabilities (Lüders and Portevin Le Châtelier-like bands), while the 980 grade TRIP steel deforms homogenously up to necking. The dramatically different deformation behaviors of these steels required the development of a new in situ experimental technique that couples volumetric synchrotron X-ray diffraction measurement of RAVF with surface strain measurement using stereo digital image correlation over the beam impingement area. Measurement results with the new technique are compared to those from a more conventional approach wherein strains are measured over the entire gage region, while RAVF measurement is the same as that in the new technique. A determination is made as to the appropriateness of the different measurement techniques in measuring the transformation behaviors for steels with homogeneous and inhomogeneous deformation behaviors. Extension of the new in situ technique to the measurement of austenite transformation under different deformation modes and to higher strain rates is discussed.

  7. Assessing phase stability and element distribution in Co-base superalloys at elevated temperatures by in situ TEM heating experiments

    Energy Technology Data Exchange (ETDEWEB)

    Eggeler, Yolita; Mueller, Julian; Spiecker, Erdmann [Lehrstuhl fuer Mikro- und Nanostrukturforschung and Center for Nanoanalysis and Electron Microscopy (CENEM), Department Werkstoffwissenschaften, Universitaet Erlangen-Nuernberg, Erlangen (Germany)

    2016-07-01

    Co-based alloys, of a composition of Co-12Al-9W, form a stable two phase γ/γ{sup '} microstructure at 900 C. γ{sup '} cubes, consisting of the L12 crystal structure are coherently embedded in a solid solution fcc (A1) γ matrix. To ensure precipitate hardening at temperatures, which are relevant to practical applications, 700-1100 C, as experienced in gas turbine applications, the stability of the γ/γ{sup '} phases is of fundamental importance. In this analysis in situ TEM studies with chip-based heating systems (by DENS solution) are applied on new Co-based superalloys. After in situ heating at apr. 900 C and controlled quenching with different quenching rates the elemental distribution at the γ/γ{sup '} interface is measured using ChemiSTEM EDX. Exploiting the driving force for interface movement resulting from temperature-dependent volume fraction of γ and γ{sup '} insight into the diffusion of individual alloying elements and the relationship between local chemistry and ordering can be gained from transient phenomena. The experimental results will be compared with theoretical calculations. This work has been carried out within the framework of the SFB-TR 103 ''Single Crystal Superalloys''.

  8. In-Situ Measurements of the Radiation Stability of Amino Acids at 15-140 K

    Science.gov (United States)

    Gerakines, Perry A.; Hudson, Reggie L.; Moore, Marla H.; Bell, Jan-Luca

    2012-01-01

    We present new kinetics data on the radiolytic destruction of amino acids measured in situ with infrared spectroscopy. Samples were irradiated at 15, 100, and 140 K with D.8-MeV protons, and amino-acid decay was followed at each temperature with and without H2O present. Observed radiation products included CO2 and amines, consistent with amino-acid decarboxylation. The half-lives of glycine, alanine, and phenylalanine were estimated for various extraterrestrial environments. Infrared spectral changes demonstrated the conversion from the non-zwitterion structure NH2-CH2(R)-COOH at 15 K to the zwitterion structure +NH3-CH2(R)-COO- at 140 K for each amino acid studied.

  9. Engineering feasibility analysis for in-situ stabilization of Burrell Township site residues

    International Nuclear Information System (INIS)

    1982-11-01

    The Burrell Township site, located in western Pennsylvania, received approximately 11,600 tons of radioactively-contaminated material in late 1956 and early 1957 from the Vitro Manufacturing Company's operations in Canonsburg, Pennsylvania. WESTON was requested to conduct an engineering study to determine the feasibility of stabilizing the site in accordance with the US Environmental Protection Agency's (EPA) interim and proposed standards (45 FR 27366--27368, April 22, 1980, and 46 FR 2556--2563, January 9, 1981). The scope of this study is limited to those alternatives that can be implemented on the site and will not require removal and offsite disposal of radioactively-contaminated material. Four alternatives for control of the radioactive material at the Burrell site were considered and evaluated, as follows: 1. Site stabilization and closure. 2. Site control and containment. 3. Waste excavation and encapsulation. 4. Waste excavation, incineration, and encapsulation. 2 refs., 32 figs., 12 tabs

  10. Properties of cement-fly ash grout admixed with bentonite, silica fume, or organic fiber

    International Nuclear Information System (INIS)

    Huang, W.H.

    1997-01-01

    A detailed laboratory study was conducted to investigate the properties of cement-fly ash grout mixtures as barriers for isolation of hazardous and low-level radioactive wastes. In the grout studied, fly ash was used to replace 30 percent by mass of cement. Three additives including bentonite, silica fume, and polypropylene fiber were used individually in the grout mixes to improve the properties of the grouts in different aspects. The flowability, bleeding, and setting time of freshly mixed grouts were determined; and the unconfined compressive strength, pore size distribution, and water permeability were determined for hardened grouts at various curing durations up to 120 days. Finally, the durability of cement-fly ash grouts was carefully examined in terms of the changes in their physical properties after different levels of exposure to sulfate attack and wet-dry cycles

  11. Tank 18-F And 19-F Tank Fill Grout Scale Up Test Summary

    International Nuclear Information System (INIS)

    Stefanko, D.; Langton, C.

    2012-01-01

    High-level waste (HLW) tanks 18-F and 19-F have been isolated from FTF facilities. To complete operational closure the tanks will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) entombing waste removal equipment, (4) discouraging future intrusion, and (5) providing an alkaline, chemical reducing environment within the closure boundary to control speciation and solubility of select radionuclides. This report documents the results of a four cubic yard bulk fill scale up test on the grout formulation recommended for filling Tanks 18-F and 19-F. Details of the scale up test are provided in a Test Plan. The work was authorized under a Technical Task Request (TTR), HLE-TTR-2011-008, and was performed according to Task Technical and Quality Assurance Plan (TTQAP), SRNL-RP-2011-00587. The bulk fill scale up test described in this report was intended to demonstrate proportioning, mixing, and transportation, of material produced in a full scale ready mix concrete batch plant. In addition, the material produced for the scale up test was characterized with respect to fresh properties, thermal properties, and compressive strength as a function of curing time.

  12. TANK 18-F AND 19-F TANK FILL GROUT SCALE UP TEST SUMMARY

    Energy Technology Data Exchange (ETDEWEB)

    Stefanko, D.; Langton, C.

    2012-01-03

    High-level waste (HLW) tanks 18-F and 19-F have been isolated from FTF facilities. To complete operational closure the tanks will be filled with grout for the purpose of: (1) physically stabilizing the tanks, (2) limiting/eliminating vertical pathways to residual waste, (3) entombing waste removal equipment, (4) discouraging future intrusion, and (5) providing an alkaline, chemical reducing environment within the closure boundary to control speciation and solubility of select radionuclides. This report documents the results of a four cubic yard bulk fill scale up test on the grout formulation recommended for filling Tanks 18-F and 19-F. Details of the scale up test are provided in a Test Plan. The work was authorized under a Technical Task Request (TTR), HLE-TTR-2011-008, and was performed according to Task Technical and Quality Assurance Plan (TTQAP), SRNL-RP-2011-00587. The bulk fill scale up test described in this report was intended to demonstrate proportioning, mixing, and transportation, of material produced in a full scale ready mix concrete batch plant. In addition, the material produced for the scale up test was characterized with respect to fresh properties, thermal properties, and compressive strength as a function of curing time.

  13. Demonstration of in situ-constructed horizontal soil containment barrier at Fernald

    International Nuclear Information System (INIS)

    Pettit, P.J.; Ridenour, D.; Walker, J.; Saugier, K.

    1994-01-01

    A new design of jet grouting tool that can be guided by horizontal well casings and that operates in the horizontal plane has been used for the in situ placement of grout and construction of a prototype horizontal barrier that is free of windows. Jet grouting techniques have been advanced to permit construction of horizontal barriers underneath contaminated soil without having to excavate or disturb the waste. The paper describes progress on the Fernald Environmental Restoration Management Corporation (FERMCO) In Situ Land Containment Project which is sponsored by the US Department of Energy's (DOE) Office of Technology Development (OTD) for DOE's Fernald Environmental Management Project (FEMP). The Fernald project is to demonstrate a novel, enabling technology for the controlled underground placement of horizontal panels of grout, and the joining of adjacent panels to construct practical, extensive barriers. Construction strategy, equipment mechanics and operating details of this new method are described

  14. Field application of activated carbon amendment for in-situ stabilization of polychlorinated biphenyls in marine sediment.

    Science.gov (United States)

    Cho, Yeo-Myoung; Ghosh, Upal; Kennedy, Alan J; Grossman, Adam; Ray, Gary; Tomaszewski, Jeanne E; Smithenry, Dennis W; Bridges, Todd S; Luthy, Richard G

    2009-05-15

    We report results on the first field-scale application of activated carbon (AC) amendment to contaminated sediment for in-situ stabilization of polychlorinated biphenyls (PCBs). The test was performed on a tidal mud flat at South Basin, adjacent to the former Hunters Point Naval Shipyard, San Francisco Bay, CA. The major goals of the field study were to (1) assess scale up of the AC mixing technology using two available, large-scale devices, (2) validate the effectiveness of the AC amendment at the field scale, and (3) identify possible adverse effects of the remediation technology. Also, the test allowed comparison among monitoring tools, evaluation of longer-term effectiveness of AC amendment, and identification of field-related factors that confound the performance of in-situ biological assessments. Following background pretreatment measurements, we successfully incorporated AC into sediment to a nominal 30 cm depth during a single mixing event, as confirmed by total organic carbon and black carbon contents in the designated test plots. The measured AC dose averaged 2.0-3.2 wt% and varied depending on sampling locations and mixing equipment. AC amendment did not impact sediment resuspension or PCB release into the water column over the treatment plots, nor adversely impactthe existing macro benthic community composition, richness, or diversity. The PCB bioaccumulation in marine clams was reduced when exposed to sediment treated with 2% AC in comparison to the control plot Field-deployed semi permeable membrane devices and polyethylene devices showed about 50% reduction in PCB uptake in AC-treated sediment and similar reduction in estimated pore-water PCB concentration. This reduction was evident even after 13-month post-treatment with then 7 months of continuous exposure, indicating AC treatment efficacy was retained for an extended period. Aqueous equilibrium PCB concentrations and PCB desorption showed an AC-dose response. Field-exposed AC after 18 months

  15. Simulation of prepackaged grout bleed under field conditions.

    Science.gov (United States)

    2014-04-01

    This report contains a summary of the research performed in the area of reproducing and determining the cause of soft : grout, which has been found in several PT (Post-Tensioned) tubes around the state of Florida. A modified version of the : Euronorm...

  16. Fatigue Behaviour of High Performance Cementitious Grout Masterflow 9500

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes the fatigue behaviour of the high performance grout MASTERFLOW 9500 subjected to cyclic loading, in air as well as submerged in water, at various frequencies and levels of maximum stress. Part of the results were also reported in [1] together with other mechanical...

  17. Grouting applications in civil engineering. Volume I and II

    International Nuclear Information System (INIS)

    Einstein, H.H.; Barvenik, M.J.

    1975-01-01

    A comprehensive description of grouting applications in civil engineering is presented that can serve as a basis for the selection of grouting methods in the borehole sealing problem. The breadth and depth of the study was assured by conducting the main part of the review, the collection and evaluation of information, without specifically considering the borehole sealing problem (but naturally incorporating any aspect of civil engineering applications that could be of potential use). Grouting is very much an art and not a science. In most cases, it is a trial and error procedure where an inexpensive method is initially tried and then a more expensive one is used until the desired results are obtained. Once a desired effect is obtained, it is difficult to credit any one procedure with the success because the results are due to the summation of all the methods used. In many cases, the method that proves successful reflects a small abnormality in the ground or structure rather than its overall characteristics. Hence, successful grouting relies heavily on good engineering judgement and experience, and not on a basic set of standard correlations or equations. 800 references

  18. Coupled Viscous Fluid Flow and Joint Deformation Analysis for Grout Injection in a Rock Joint

    Science.gov (United States)

    Kim, Hyung-Mok; Lee, Jong-Won; Yazdani, Mahmoud; Tohidi, Elham; Nejati, Hamid Reza; Park, Eui-Seob

    2018-02-01

    Fluid flow modeling is a major area of interest within the field of rock mechanics. The main objective of this study is to gain insight into the performance of grout injection inside jointed rock masses by numerical modeling of grout flow through a single rock joint. Grout flow has been widely simulated using non-Newtonian Bingham fluid characterized by two main parameters of dynamic viscosity and shear yield strength both of which are time dependent. The increasing value of these properties with injection time will apparently affect the parameters representing the grouting performance including grout penetration length and volumetric injection rate. In addition, through hydromechanical coupling a mutual influence between the injection pressure from the one side and the joint opening/closing behavior and the aperture profile variation on the other side is anticipated. This is capable of producing a considerable impact on grout spread within the rock joints. In this study based on the Bingham fluid model, a series of numerical analysis has been conducted using UDEC to simulate the flow of viscous grout in a single rock joint with smooth parallel surfaces. In these analyses, the time-dependent evolution of the grout fluid properties and the hydromechanical coupling have been considered to investigate their impact on grouting performance. In order to verify the validity of these simulations, the results of analyses including the grout penetration length and the injection flow rate were compared with a well-known analytical solution which is available for the simple case of constant grout properties and non-coupled hydraulic analysis. The comparison demonstrated that the grout penetration length can be overestimated when the time-dependent hardening of grout material is not considered. Moreover, due to the HM coupling, it was shown that the joint opening induced by injection pressure may have a considerable increasing impression on the values of penetration length and

  19. Field Deployment for In-situ Metal and Radionuclide Stabilization by Microbial Metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Turick, C. E.; Knox, A. S.; Dixon, K. L.; Roseberry, R. J.; Kritzas, Y. G

    2005-09-26

    A novel biotechnology is reported here that was demonstrated at SRS that facilitates metal and actinide immobilization by incorporating the physiology and ecology of indigenous bacteria. This technology is based on our previous work with pyomelanin-producing bacteria isolated from SRS soils. Through tyrosine supplementation, overproduction of pyomelanin was achieved, which lead ultimately to metal and actinide immobilization, both in-vitro and in-situ. Pyomelanin is a recalcitrant microbial pigment and a humic type compound in the class of melanin pigments. Pyomelanin has electron shuttling and metal chelation capabilities and thus accelerates the bacterial reduction and/or immobilization of metals. Pyomelanin is produced outside the cell and either diffuses away or attaches to the cell surface. In either case, the reduced pyomelanin is capable of transferring electrons to metals as well as chelating metals. Because of its recalcitrance and redox cycling properties, pyomelanin molecules can be used over and over again for metal transformation. When produced in excess, pyomelanin produced by one bacterial species can be used by other species for metal reduction, thereby extending the utility of pyomelanin and further accelerating metal immobilization rates. Soils contaminated with Ni and U were the focus of this study in order to develop in-situ, metal bioimmobilization technologies. We have demonstrated pyomelanin production in soil from the Tims Branch area of SRS as a result of tyrosine amendments. These results were documented in laboratory soil column studies and field deployment studies. The amended soils demonstrated increased redox behavior and sequestration capacity of U and transition metals following pyomelanin production. Treatments incorporating tyrosine and lactate demonstrated the highest levels of pyomelanin production. In order to determine the potential use of this technology at other areas of SRS, pyomelanin producing bacteria were also quantified

  20. A novel strategy for high-stability lithium sulfur batteries by in situ formation of polysulfide adsorptive-blocking layer

    Science.gov (United States)

    Jin, Liming; Li, Gaoran; Liu, Binhong; Li, Zhoupeng; Zheng, Junsheng; Zheng, Jim P.

    2017-07-01

    Lithium sulfur (Lisbnd S) batteries are one of the most promising energy storage devices owing to their high energy and power density. However, the shuttle effect as a key barrier hinders its practical application by resulting in low coulombic efficiency and poor cycling performance. Herein, a novel design of in situ formed polysulfide adsorptive-blocking layer (PAL) on the cathode surface was developed to tame the polysulfide shuttling and promote the cycling stability for Lisbnd S batteries. The PAL is consisted of La2S3, which is capable to chemically adsorb polysulfide via the strong interaction of Lasbnd S bond and Ssbnd S bond, and build an effective barrier against sulfur escaping. Moreover, the La2S3 is capable to suppress the crystallization of Li2S and promote the ion transfer, which contributes to the reduced internal resistance of batteries. Furthermore, the by-product LiNO3 simultaneously forms a stable anode solid and electrolyte interface to further inhibit the polysulfide shuttle. By this simple and convenient method, the resultant Lisbnd S batteries achieved exceptional cycling stability with an ultralow decay rate of 0.055% since the 10th cycle.

  1. Development of cellulase-nanoconjugates with enhanced ionic liquid and thermal stability for in situ lignocellulose saccharification.

    Science.gov (United States)

    Grewal, Jasneet; Ahmad, Razi; Khare, S K

    2017-10-01

    The present work aimed to improve catalytic efficiency of Trichoderma reesei cellulase for enhanced saccharification. The cellulase was immobilized on two nanomatrices i.e. magnetic and silica nanoparticles with immobilization efficiency of 85% and 76% respectively. The nanobioconjugates exhibited increase in V max , temperature optimum, pH and thermal stability as compared with free enzyme. These could be efficiently reused for five repeated cycles and were stable in 1-ethyl-3-methylimidazoliumacetate [EMIM][Ac], an ionic liquid. Ionic liquids (IL) are used as green solvents to dissolve lignocellulosic biomass and facilitate better saccharification. The cellulase immobilized on magnetic nanoparticles was used for in situ saccharification of [EMIM][Ac] pretreated sugarcane bagasse and wheat straw for two cycles. The structural deconstruction and decrease in biomass crystallinity was confirmed by SEM, XRD and FTIR. The high hydrolysis yields (∼89%) obtained in this one-pot process coupled with IL stability and recycled use of immobilized cellulase, potentiates its usefulness in biorefineries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Non-Aqueous Sol-Gel Synthesis of FePt Nanoparticles in the Absence of In Situ Stabilizers

    Directory of Open Access Journals (Sweden)

    Tobias Preller

    2018-05-01

    Full Text Available The synthesis of FePt nanocrystals is typically performed in an organic solvent at rather high temperatures, demanding the addition of the in situ stabilizers oleic acid and oleylamine to produce monomodal particles with well-defined morphologies. Replacing frequently-used solvents with organic media bearing functional moieties, the use of the stabilizers can be completely circumvented. In addition, various morphologies and sizes of the nanocrystals can be achieved by the choice of organic solvent. The kinetics of particle growth and the change in the magnetic behavior of the superparamagnetic FePt nanocrystals during the synthesis with a set of different solvents, as well as the resulting morphologies and stoichiometries of the nanoparticles were determined by powder X-ray diffraction (PXRD, small-angle X-ray scattering (SAXS, transmission electron microscopy (TEM, inductively coupled plasma optical emission spectroscopy (ICP-OES/mass spectrometry (ICP-MS, and superconducting quantum interference device (SQUID measurements. Furthermore, annealing of the as-prepared FePt nanoparticles led to the ordered L10 phase and, thus, to hard magnetic materials with varying saturation magnetizations and magnetic coercivities.

  3. SAVANNAH RIVER SITE R-REACTOR DISASSEMBLY BASIN IN-SITU DECOMMISSIONING -10499

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Serrato, M.; Blankenship, J.; Griffin, W.

    2010-01-04

    The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate intact, structurally sound facilities that are no longer needed for their original purpose, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the 105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate it from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,384 cubic meters or 31,894 cubic yards. Portland cement-based structural fill materials were designed and tested for the reactor ISD project, and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and material flow considerations, maximum lift heights and differential height requirements were determined. Pertinent data and information related to the SRS 105-R Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material

  4. Optical and structural properties of radiolytically in situ synthesized silver nanoparticles stabilized by chitosan/poly(vinyl alcohol) blends

    International Nuclear Information System (INIS)

    Krstić, Jelena; Spasojević, Jelena; Radosavljević, Aleksandra; Šiljegovć, Milorad; Kačarević-Popović, Zorica

    2014-01-01

    In this study, the potential of chitosan/poly(vinyl alcohol) (CS/PVA) blends as capping agent for stabilization of Ag-nanoparticles (Ag NPs) during their in situ gamma irradiation induced synthesis was investigated. The UV–vis absorption spectra show the surface plasmon absorption band around 410 nm, which confirms the formation of Ag-nanoparticles. It was found that the composition of CS/PVA blend affected the size of the obtained Ag-nanoparticles, as well as the parameters such as density, molar concentration and effective surface area, calculated from the experimentally obtained UV–vis absorption spectra and spectra obtained by simulation according to the Mie theory. SEM micrograph and XRD measurement indicated a spherical morphology and face centered cubic crystal structure of Ag-nanoparticles, with diameter around 12 nm. The values of optical band gap energy between valence and conduction bands (E g ), calculated from the UV–vis absorption spectra, also show dependence on the blend composition for Ag–CS/PVA colloids as well as for Ag–CS/PVA nanocomposites. - Highlights: • Ag NPs were synthesized by γ-irradiation and stabilized by CS/PVA blends. • Composition of CS/PVA blends has influence on the size of spherical Ag NPs. • simulation based on Mie theory was used to calculate the parameters of Ag NPs. • Ag NPs are stabilized through interactions with -OH and -NH 2 groups of polymers. • Optical band gap energy was calculated from UV–vis spectra by Tauc's expression

  5. In Situ Microbial Community Control of the Stability of Bio-reduced Uranium

    International Nuclear Information System (INIS)

    Baldwin, Brett R.; Peacock, Aaron D.; Resch, Charles T.; Arntzen, Evan; Smithgall, Amanda N.; Pfiffner, Susan; Gan, M.; McKinley, James P.; Long, Philip E.; White, David C.

    2008-01-01

    In aerobic aquifers typical of many Department of Energy (DOE) legacy waste sites, uranium is present in the oxidized U(VI) form which is more soluble and thus more mobile. Field experiments at the Old Rifle UMTRA site have demonstrated that biostimulation by electron donor addition (acetate) promotes biological U(VI) reduction (2). However, U(VI) reduction is reversible and oxidative dissolution of precipitated U(IV) after the cessation of electron donor addition remains a critical issue for the application of biostimulation as a treatment technology. Despite the potential for oxidative dissolution, field experiments at the Old Rifle site have shown that rapid reoxidation of bio-reduced uranium does not occur and U(VI) concentrations can remain at approximately 20% of background levels for more than one year. The extent of post-amendment U(VI) removal and the maintenance of bioreduced uranium may result from many factors including U(VI) sorption to iron-containing mineral phases, generation of H2S or FeS0.9, or the preferential sorption of U(VI) by microbial cells or biopolymers, but the processes controlling the reduction and in situ reoxidation rates are not known. To investigate the role of microbial community composition in the maintenance of bioreduced uranium, in-well sediment incubators (ISIs) were developed allowing field deployment of amended and native sediments during on-going experiments at the site. Field deployment of the ISIs allows expedient interrogation of microbial community response to field environmental perturbations and varying geochemical conditions.

  6. In Situ Microbial Community Control of the Stability of Bio-reduced Uranium

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, Brett, R.; Peacock, Aaron, D.; Resch, Charles, T.; Arntzen, Evan; Smithgall, Amanda, N.; Pfiffner, Susan; Gan, M.; McKinley, James, P.; Long, Philip, E.; White, David, C.

    2008-03-28

    In aerobic aquifers typical of many Department of Energy (DOE) legacy waste sites, uranium is present in the oxidized U(VI) form which is more soluble and thus more mobile. Field experiments at the Old Rifle UMTRA site have demonstrated that biostimulation by electron donor addition (acetate) promotes biological U(VI) reduction (2). However, U(VI) reduction is reversible and oxidative dissolution of precipitated U(IV) after the cessation of electron donor addition remains a critical issue for the application of biostimulation as a treatment technology. Despite the potential for oxidative dissolution, field experiments at the Old Rifle site have shown that rapid reoxidation of bio-reduced uranium does not occur and U(VI) concentrations can remain at approximately 20% of background levels for more than one year. The extent of post-amendment U(VI) removal and the maintenance of bioreduced uranium may result from many factors including U(VI) sorption to iron-containing mineral phases, generation of H2S or FeS0.9, or the preferential sorption of U(VI) by microbial cells or biopolymers, but the processes controlling the reduction and in situ reoxidation rates are not known. To investigate the role of microbial community composition in the maintenance of bioreduced uranium, in-well sediment incubators (ISIs) were developed allowing field deployment of amended and native sediments during on-going experiments at the site. Field deployment of the ISIs allows expedient interrogation of microbial community response to field environmental perturbations and varying geochemical conditions.

  7. Stabilized Sulfonated Aromatic Polymers by in situ Solvothermal Cross-Linking

    Energy Technology Data Exchange (ETDEWEB)

    Di Vona, Maria Luisa, E-mail: divona@uniroma2.it; Sgreccia, Emanuela [Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Rome (Italy); Narducci, Riccardo; Pasquini, Luca [Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Rome (Italy); MAtériaux Divisés, Interfaces, Réactivité, ELectrochimie (MADIREL – UMR 7246), Aix Marseille Université, Marseille (France); Hou, Hongying [Faculty of Material and Engineering, Kunming University of Science and Technology, Kunming (China); Knauth, Philippe [MAtériaux Divisés, Interfaces, Réactivité, ELectrochimie (MADIREL – UMR 7246), Aix Marseille Université, Marseille (France)

    2014-10-10

    The cross-link reaction via sulfone bridges of sulfonated polyether ether ketone (SPEEK) by thermal treatment at 180°C in presence of dimethylsulfoxide is discussed. The modifications of properties subsequent to the cross-linking are presented. The mechanical strength as well as the hydrolytic stability increased with the thermal treatment time, i.e., with the degree of cross-linking. The proton conductivity was determined as function of temperature, IEC, degree of cross-linking, and hydration number. The memory effect, which is the membrane ability to “remember” the water uptake reached at high temperature also at lower temperature, is exploited in order to achieve high values of conductivity. Membranes swelled at 110°C can reach a conductivity of 0.14 S/cm at 80°C with a hydration number (λ) of 73.

  8. Stabilized sulfonated aromatic polymers by in situ solvothermal cross-linking

    Directory of Open Access Journals (Sweden)

    Maria Luisa eDi Vona

    2014-10-01

    Full Text Available The cross-link reaction via sulfone bridges of sulfonated polyetheretherketone (SPEEK by thermal treatment at 180 °C in presence of dimethylsulfoxide (DMSO is discussed. The modifications of properties subsequent to the cross-linking are presented. The mechanical strength as well as the hydrolytic stability increased with the thermal treatment time, i.e., with the degree of cross-linking. The proton conductivity was determined as function of temperature, IEC, degree of cross-linking and hydration number. The memory effect, which is the membrane ability to remember the water uptake reached at high temperature also at lower temperature, is exploited in order to achieve high values of conductivity. Membranes swelled at 110 °C can reach a conductivity of 0.14 S/cm at 80°C with a hydration number ( of 73.

  9. Grouting design based on characterization of the fractured rock. Presentation and demonstration of a methodology

    Energy Technology Data Exchange (ETDEWEB)

    Fransson, Aasa (SWECO Environment, Stockholm (Sweden); Chalmers Univ. of Technology, Goeteborg (Sweden))

    2008-12-15

    The design methodology presented in this document is based on an approach that considers the individual fractures. The observations and analyses made during production enable the design to adapt to the encountered conditions. The document is based on previously published material and overview flow charts are used to show the different steps. Parts of or the full methodology has been applied for a number of tunneling experiments and projects. SKB projects in the Aespoe tunnel include a pillar experiment and pre-grouting of a 70 meter long tunnel (TASQ). Further, for Hallandsas railway tunnel (Skaane south Sweden), a field pre-grouting experiment and design and post-grouting of a section of 133 meters have been made. For the Nygard railway tunnel (north of Goeteborg, Sweden), design and grouting of a section of 86 meters (pre-grouting) and 60 meters (post-grouting) have been performed. Finally, grouting work at the Tornskog tunnel (Stockholm, Sweden) included design and grouting along a 100 meter long section of one of the two tunnel tubes. Of importance to consider when doing a design and evaluating the result are: - The identification of the extent of the grouting needed based on inflow requirements and estimates of tunnel inflow before grouting. - The selection of grout and performance of grouting materials including penetration ability and length. The penetration length is important for the fan geometry design. - The ungrouted compared to the grouted and excavated rock mass conditions: estimates of tunnel inflow and (if available) measured inflows after grouting and excavation. Identify if possible explanations for deviations. For the Hallandsas, Nygard and Tornskog tunnel sections, the use of a Pareto distribution and the estimate of tunnel inflow identified a need for sealing small aperture fractures (< 50 - 100 mum) to meet the inflow requirements. The tunneling projects show that using the hydraulic aperture as a basis for selection of grout is a good

  10. Grouting design based on characterization of the fractured rock. Presentation and demonstration of a methodology

    International Nuclear Information System (INIS)

    Fransson, Aasa

    2008-12-01

    The design methodology presented in this document is based on an approach that considers the individual fractures. The observations and analyses made during production enable the design to adapt to the encountered conditions. The document is based on previously published material and overview flow charts are used to show the different steps. Parts of or the full methodology has been applied for a number of tunneling experiments and projects. SKB projects in the Aespoe tunnel include a pillar experiment and pre-grouting of a 70 meter long tunnel (TASQ). Further, for Hallandsas railway tunnel (Skaane south Sweden), a field pre-grouting experiment and design and post-grouting of a section of 133 meters have been made. For the Nygard railway tunnel (north of Goeteborg, Sweden), design and grouting of a section of 86 meters (pre-grouting) and 60 meters (post-grouting) have been performed. Finally, grouting work at the Tornskog tunnel (Stockholm, Sweden) included design and grouting along a 100 meter long section of one of the two tunnel tubes. Of importance to consider when doing a design and evaluating the result are: - The identification of the extent of the grouting needed based on inflow requirements and estimates of tunnel inflow before grouting. - The selection of grout and performance of grouting materials including penetration ability and length. The penetration length is important for the fan geometry design. - The ungrouted compared to the grouted and excavated rock mass conditions: estimates of tunnel inflow and (if available) measured inflows after grouting and excavation. Identify if possible explanations for deviations. For the Hallandsas, Nygard and Tornskog tunnel sections, the use of a Pareto distribution and the estimate of tunnel inflow identified a need for sealing small aperture fractures (< 50 - 100 μm) to meet the inflow requirements. The tunneling projects show that using the hydraulic aperture as a basis for selection of grout is a good

  11. In situ high-frequency UV-Vis spectrometer probes for investigating runoff processes and end member stability.

    Science.gov (United States)

    Schwab, Michael; Weiler, Markus; Pfister, Laurent; Klaus, Julian

    2014-05-01

    In recent years, several limitations as to the application of end member mixing analysis with isotope and geochemical tracers have been revealed: unstable end member solutions, inputs varying in space and time, and unrealistic mixing assumptions. In addition, the necessary high-frequency sampling using conventional methods is time and resources consuming, and hence most sampling rates are not suitable for capturing the response times of the majority of observed headwater catchments. However, high-frequency observations are considered fundamental for gaining new insights into hydrological systems. In our study, we have used two portable, in situ, high-frequency UV-Vis spectrometers (spectro::lyser; scan Messtechnik GmbH) to investigate the variability of several signatures in streamflow and end member stability. The spectro::lyser measures TOC, DOC, nitrate and the light absorption spectrum from 220 to 720 nm with 2.5 nm increment. The Weierbach catchment (0.45 km2) in the Attert basin (297 km2) in Luxemburg is a small headwater research catchment (operated by the CRP Gabriel Lippmann), which is completely forested and underlain by schist bedrock. The catchment is equipped with a dense network of hydrological instruments and for this study, the outlet of the Weierbach catchment was equipped with one spectro::lyser, permanently sensing stream water at a 15 minutes time step over several months. Hydrometric and meteorologic data was compared with the high-frequency spectro::lyser time series of TOC, DOC, nitrate and the light absorption spectrum, to get a first insight into the behaviour of the catchment under different environmental conditions. As a preliminary step for a successful end member mixing analysis, the stability of rainfall, soil water, and groundwater was tested with one spectro::lyser, both temporally and spatially. Thereby, we focused on the investigation of changes and patterns of the light absorption spectrum of the different end members and the

  12. [Research on the application of in-situ biological stabilization solidification technology in chromium contaminated site management].

    Science.gov (United States)

    Zhang, Jian-rong; Li, Juan; Xu, Wei

    2013-09-01

    In-situ biological stabilization solidification (SS) technology is an effective ground water risk control method for chromium contaminated sites. Through on-site engineering test, this paper has preliminarily validated the remediation effect of in-situ SS method on a southern chromium contaminated site. The engineering test site has an area of approximately 600 m2, and is located at the upstream of the contaminated area. Due to the severe contamination of chromium, the total chromium concentration reached up to 11,850 mg x kg(-1), while the hexavalent chromium concentration reached up to 349 mg x kg(-1), and the most severely contaminated soil had a depth of -0.5 - -2 m. Variations in hexavalent chromium and total chromium concentration in groundwater were observed through the injection of reducing agents and microbial regulators into the injection wells in the test site, and through the monitoring analysis at different time and different depth under the action of the injection agents. Results of the engineering test showed that the on-site SS technology significantly changed the chromium speciation in soil and then reduced the migration of chromium, thus the groundwater risk was reduced. The injected agents had a good effect of hexavalent chromium remediation in groundwater within the effective range of the injection wells, and the SS rate of hexavalent chromium into trivalent chromium reached 94%-99.9%, the SS rate of total chromium fixation reached 83.9%-99.8%. The test results are of significant reference value for the remediation of contaminated sites with features of shallow groundwater depth and soil mainly consisting of silty clay and sandy clay.

  13. Design of top covers supporting aerobic in situ stabilization of old landfills - An experimental simulation in lysimeters

    Energy Technology Data Exchange (ETDEWEB)

    Hrad, Marlies [Institute of Waste Management, Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna (Austria); Huber-Humer, Marion, E-mail: marion.huber-humer@boku.ac.at [Institute of Waste Management, Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna (Austria); Wimmer, Bernhard; Reichenauer, Thomas G. [Health and Environment Department, Environmental Resources and Technologies, AIT Austrian Institute of Technology GmbH, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Tested engineered covers as surrogate to gas extraction during and after in situ aeration. Black-Right-Pointing-Pointer Examined how covers influence gas emissions, water balance and leachate generation. Black-Right-Pointing-Pointer Investigated effect of top covers on air-distribution in waste mass during aeration. Black-Right-Pointing-Pointer We suggest criteria and cover design to meet the demands during and after aeration. Black-Right-Pointing-Pointer Such cover systems may offer greenhouse gas emission reduction also after active aeration. - Abstract: Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 Multiplication-Sign 2 Multiplication-Sign 3 m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH{sub 4} loadings up to 300 l CH{sub 4}/m{sup 2} d. In addition, the compost material provided high air permeability

  14. IN-SITU CHEMICAL STABILIZATION OF METALS AND RADIONUCLIDES THROUGH ENHANCED ANAEROBIC REDUCTIVE PRECIPITATION

    Energy Technology Data Exchange (ETDEWEB)

    Christopher C. Lutes; Angela Frizzell, PG; Todd A. Thornton; James M. Harrington

    2003-08-01

    The objective of this NETL sponsored bench-scale study was to demonstrate the efficacy of enhanced anaerobic reductive precipitation (EARP) technology for precipitating uranium using samples from contaminated groundwater at the Fernald Closure Project (FCP) in Cincinnati, Ohio. EARP enhances the natural biological reactions in the groundwater through addition of food grade substrates (typically molasses) to drive the oxidative-reductive potential of the groundwater to a lower, more reduced state, thereby precipitating uranium from solution. In order for this in-situ technology to be successful in the long term, the precipitated uranium must not be re-dissolved at an unacceptable rate once groundwater geochemical conditions return to their pretreatment, aerobic state. The approach for this study is based on the premise that redissolution of precipitated uranium will be slowed by several mechanisms including the presence of iron sulfide precipitates and coatings, and sorption onto fresh iron oxides. A bench-scale study of the technology was performed using columns packed with site soil and subjected to a continuous flow of uranium-contaminated site groundwater (476 {micro}g/L). The ''treated'' column received a steady stream of dilute food grade molasses injected into the contaminated influent. Upon attainment of a consistently reducing environment and demonstrated removal of uranium, an iron sulfate amendment was added along with the molasses in the influent solution. After a month long period of iron addition, the treatments were halted, and uncontaminated, aerobic, unamended water was introduced to the treated column to assess rebound of uranium concentrations. In the first two months of treatment, the uranium concentration in the treated column decreased to the clean-up level (30 {micro}g/L) or below, and remained there for the remainder of the treatment period. A brief period of resolubilization of uranium was observed as the treated column

  15. On the thermal stability of ultrafine-grained Al stabilized by in-situ amorphous Al{sub 2}O{sub 3} network

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Martin, E-mail: martin.balog@savba.sk [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States); Hu, Tao [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States); Krizik, Peter [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Castro Riglos, Maria Victoria [Centro Atómico Bariloche, Av. Bustillo 9.500 (8400) Bariloche, Río Negro (Argentina); Saller, Brandon D.; Yang, Hanry; Schoenung, Julie M.; Lavernia, Enrique J. [Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616 (United States)

    2015-11-11

    Bulk Al materials with average grain sizes of 0.47 and 2.4 µm, were fabricated by quasi-isostatic forging consolidation of two types of Al powders with average particle sizes of 1.3 and 8.9 μm, respectively. By utilizing the native amorphous Al{sub 2}O{sub 3} (am-Al{sub 2}O{sub 3}) film on the Al powders surfaces, a continuous, ∼7 nm thick, am-Al{sub 2}O{sub 3} network was formed in situ in the Al specimens. Systematic investigation of the changes to the am-Al{sub 2}O{sub 3} network embedded in the Al matrix upon heating and annealing up to 600 °C was performed by transmission electron microscopy (TEM). At the same time, the stability of the Al grain structure was studied by transmission Kikuchi diffraction (TKD), electron back-scatter diffraction (EBSD), and TEM. The am-Al{sub 2}O{sub 3} network remained stable after annealing at 400 °C for 24 h. In-situ TEM studies revealed that at temperatures ≥450 °C, phase transformation of the am-Al{sub 2}O{sub 3} network to crystalline γ-Al{sub 2}O{sub 3} particles occurred. After annealing at 600 °C for 24 h the transformation was completed, whereby only nanometric γ-Al{sub 2}O{sub 3} particles with an average size of 28 nm resided on the high angle grain boundaries of Al. Due to the pinning effect of γ-Al{sub 2}O{sub 3}, the Al grain and subgrain structures remained unchanged during annealing up to 600 °C for 24 h. The effect of the am-Al{sub 2}O{sub 3}→γ-Al{sub 2}O{sub 3} transformation on the mechanical properties of ultrafine- and fine-grained Al is discussed from the standpoint of the underlying mechanisms.

  16. Stabilization and isolation of low-level liquid waste disposal sites

    International Nuclear Information System (INIS)

    Phillips, S.J.; Gilbert, T.W.

    1987-01-01

    Rockwell Hanford Operations is developing and testing equipment for stabilization and isolation of low-level radioactive liquid waste disposal sites. Stabilization and isolation are accomplished by a dynamic consolidation and particulate grout injection system. System equipment components include: a mobile grout plant for transport, mixing, and pumping of particulate grout; a vibratory hammer/extractor for consolidation of waste, backfill, and for emplacement of the injector; dynamic consolidation/injector probe for introducing grout into fill material; and an open-void surface injector that uses surface or subsurface mechanical or pneumatic packers and displacement gas filtration for introducing grout into disposal structure access piping. Treatment of a liquid-waste disposal site yields a physically stable, cementitious monolith. Additional testing and modification of this equipment for other applications to liquid waste disposal sites is in progress

  17. Integrity assessment of grouted posttensioning cables and reinforced concrete of a nuclear containment building

    Science.gov (United States)

    Philipose, K.; Shenton, B.

    2011-04-01

    The Containment Buildings of CANDU Nuclear Generating Stations were designed to house nuclear reactors and process equipment and also to provide confinement of releases from a potential nuclear accident such as a Loss Of Coolant Accident (LOCA). To meet this design requirement, a post-tensioning system was designed to induce compressive stresses in the structure to counteract the internal design pressure. The CANDU reactor building at Gentilly-1 (G-1), Quebec, Canada (250 MWe) was built in the early 1970s and is currently in a decommissioned state. The structure at present is under surveillance and monitoring. In the year 2000, a field investigation was conducted as part of a condition assessment and corrosion was detected in some of the grouted post-tension cable strands. However, no further work was done at that time to determine the cause, nature, impact and extent of the corrosion. An investigation of the Gentilly-1 containment building is currently underway to assess the condition of grouted post-tensioning cables and reinforced concrete. At two selected locations, concrete and steel reinforcements were removed from the containment building wall to expose horizontal cables. Individual cable strands and reinforcement bars were instrumented and measurements were taken in-situ before removing them for forensic examination and destructive testing to determine the impact of ageing and corrosion. Concrete samples were also removed and tested in a laboratory. The purpose of the field investigation and laboratory testing, using this structure as a test bed, was also to collect material ageing data and to develop potential Nondestructive Examination (NDE) methods to monitor Containment Building Integrity. The paper describes the field work conducted and the test results obtained for concrete, reinforcement and post-tensioning cables.

  18. Literature Review of the Effects of Tetraphenylborate on Saltstone Grout: Benzene Evolution and TCLP Performance

    International Nuclear Information System (INIS)

    HAY, MICHAEL

    2004-01-01

    As part of the program to disposition the tetraphenylborate (TPB) in Tank 48H and return the tank to service, Salt Processing Development requested a review of the literature to assess the state of knowledge pertaining to incorporation of tetraphenylborate slurries in saltstone grout with respect to benzene generation rates and leaching performance. Examination of past studies conducted at Savannah River Site (SRS) on the incorporation of TPB slurries in saltstone provides a basis for developing a more focused scope of experimental studies. Tank 48H currently contains potassium and cesium tetraphenylborate salts as a result of a demonstration of the In Tank Precipitation (ITP) process in 1983 and subsequent ITPradioactive start-up operations in 1995. The tank currently contains approximately 240,000 gallons of salt solution with approximately 19,000 kg of potassium and cesium tetraphenylborate salts. The presence of the TPB salts makes the waste incompatible with existing High Level Waste treatment facilities. The TPB salts in Tank 48H must be treated or removed to meet the scheduled return to service date of 2007. The two preferred options for disposition of the TBP slurries in Tank 48H include: (1) Aggregation of the material with the Defense Waste Processing Facility (DWPF) recycle stream and disposal in the Saltstone Processing Facility (SPF), and (2) In-Situ Thermal Decomposition using heat in combination with pH reduction and catalyst addition. The current literature review along with the current experimental studies provide a basis for determining the feasibility of the option to incorporate the TPB slurries into saltstone grout

  19. Integrity assessment of grouted posttensioning cables and reinforced concrete of a nuclear containment building

    Directory of Open Access Journals (Sweden)

    Shenton B.

    2011-04-01

    Full Text Available The Containment Buildings of CANDU Nuclear Generating Stations were designed to house nuclear reactors and process equipment and also to provide confinement of releases from a potential nuclear accident such as a Loss Of Coolant Accident (LOCA. To meet this design requirement, a post-tensioning system was designed to induce compressive stresses in the structure to counteract the internal design pressure. The CANDU reactor building at Gentilly-1 (G-1, Quebec, Canada (250 MWe was built in the early 1970s and is currently in a decommissioned state. The structure at present is under surveillance and monitoring. In the year 2000, a field investigation was conducted as part of a condition assessment and corrosion was detected in some of the grouted post-tension cable strands. However, no further work was done at that time to determine the cause, nature, impact and extent of the corrosion. An investigation of the Gentilly-1 containment building is currently underway to assess the condition of grouted post-tensioning cables and reinforced concrete. At two selected locations, concrete and steel reinforcements were removed from the containment building wall to expose horizontal cables. Individual cable strands and reinforcement bars were instrumented and measurements were taken in-situ before removing them for forensic examination and destructive testing to determine the impact of ageing and corrosion. Concrete samples were also removed and tested in a laboratory. The purpose of the field investigation and laboratory testing, using this structure as a test bed, was also to collect material ageing data and to develop potential Nondestructive Examination (NDE methods to monitor Containment Building Integrity. The paper describes the field work conducted and the test results obtained for concrete, reinforcement and post-tensioning cables.

  20. Road Maintenance Experience Using Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization as Ground Rehabilitation

    Science.gov (United States)

    Fakhar, A. M. M.; Asmaniza, A.

    2016-07-01

    There are many types of ground rehabilation and improvement that can be consider and implement in engineering construction works for soil improvement in order to prevent road profile deformation in later stage. However, when comes to road maintenance especially on operated expressways, not all method can be apply directly as it must comply to opreation's working window and lane closure basis. Key factors that considering ideal proposal for ground rehabilitation are time, cost, quality and most importantly practicality. It should provide long lifespan structure in order to reduce continuous cycle of maintenance. Thus, this paper will present two approaches for ground rehabilitation, namely Polyurethane (PU) Foam Injection System and Geocrete Soil Stabilization. The first approach is an injection system which consists two-parts chemical grout of Isocynate and Polyol when mixed together within soil structure through injection will polymerized with volume expansion. The strong expansion of grouting causes significant compression and compacting of the surrounding soil and subsequently improve ground properties and uplift sunken structure. The later is a cold in-place recyclying whereby mixture process that combines in-situ soil materials, cement, white powder (alkaline) additive and water to produce hard yet flexible and durable ground layer that act as solid foundation with improved bearing capacity. The improvement of the mechanical behaviour of soil through these two systems is investigated by an extensive testing programme which includes in-situ and laboratory test in determining properties such as strength, stiffness, compressibility, bearing capacity, differential settlement and etc.

  1. Experimental Study on Post Grouting Bearing Capacity of Large Diameter Bored Piles

    Directory of Open Access Journals (Sweden)

    Wang Duanduan

    2015-01-01

    Full Text Available Post grouting can improve the inherent defects such as the formation of the mud cake at pile side and the sediment at pile end in the process of bored pile construction. Thus post grouting has been widely used in Engineering. The purpose of this paper is to research the influences of post grouting to pile bearing capacity more systematically and intuitively. Combined with the static load test of four test piles in Weihe River Bridge test area of new airport highway in Xi’an, the bearing capacity and settlement of routine piles and post grouting piles are comparatively analyzed. The test results show that under the same geological condition, post grouting can improve the properties of pile tip and pile shaft soil of bored piles significantly, enhance the ultimate resistance, improve the ultimate bearing capacity and reduce the pile tip settlement. Then post grouting can aim to optimize pile foundation.

  2. Thermo-stabilized, porous polyimide microspheres prepared from nanosized SiO2 templating via in situ polymerization

    Directory of Open Access Journals (Sweden)

    M. Q. Liu

    2015-01-01

    Full Text Available In this article, we addressed a feasible and versatile method of the fabrication of porous polyimide microspheres presenting excellent heat resistance. The preparation process consisted of two steps. Firstly, a novel polyimide/nano-silica composite microsphere was prepared via the self-assembly structures of poly(amic acid (PAA, precursor of PI/nanosized SiO2 blends after in situ polymerization, following the two-steps imidization. Subsequently, the encapsulated nanoparticles were etched away by hydrofluoric acid treatment, giving rise to the pores. It is found the composite structure of PI/SiO2 is a precondition of the formation of nanoporous structures, furthermore, the morphology of the resultant pore could be relatively tuned by changing the content and initial morphology of silica nano-particles trapped into PI matrix. The thermal properties of the synthesized PI porous spheres were studied, indicating that the introduction of nanopores could not effectively influence the thermal stabilities of PI microspheres. Moreover, the fabrication technique described here may be extended to other porous polymer systems.

  3. Uranium Metal Reaction Behavior in Water, Sludge, and Grout Matrices

    Energy Technology Data Exchange (ETDEWEB)

    Delegard, Calvin H.; Schmidt, Andrew J.

    2009-05-27

    This report summarizes information and data on the reaction behavior of uranium metal in water, in water-saturated simulated and genuine K Basin sludge, and in grout matrices. This information and data are used to establish the technical basis for metallic uranium reaction behavior for the K Basin Sludge Treatment Project (STP). The specific objective of this report is to consolidate the various sources of information into a concise document to serve as a high-level reference and road map for customers, regulators, and interested parties outside the STP (e.g., external reviewers, other DOE sites) to clearly understand the current basis for the corrosion of uranium metal in water, sludge, and grout.

  4. Uranium Metal Reaction Behavior in Water, Sludge, and Grout Matrices

    Energy Technology Data Exchange (ETDEWEB)

    Delegard, Calvin H.; Schmidt, Andrew J.

    2008-09-25

    This report summarizes information and data on the reaction behavior of uranium metal in water, in water-saturated simulated and genuine K Basin sludge, and in grout matrices. This information and data are used to establish the technical basis for metallic uranium reaction behavior for the K Basin Sludge Treatment Project (STP). The specific objective of this report is to consolidate the various sources of information into a concise document to serve as a high-level reference and road map for customers, regulators, and interested parties outside the STP (e.g., external reviewers, other DOE sites) to clearly understand the current basis for the corrosion of uranium metal in water, sludge, and grout.

  5. Implementation of an ex situ stabilization technique at the Sand Springs superfund site to solidify and stabilize acid tar sludges involving a quick-lime based stabilization process and innovative equipment design

    International Nuclear Information System (INIS)

    McManus, R.W.; Grajczak, P.; Wilcoxson, J.C.; Webster, S.D.

    1997-01-01

    An old refinery site was safely remediated a year before schedule and for 25% less than final engineering estimates for the stabilization remedy thanks to energetic project management and innovative design involving ex situ stabilization/solidification of acid tar sludges. A quicklime based process, Dispersion by Chemical Reaction (DCR trademark), was employed to solidify and stabilize (SS) over 103,000 cubic meters (135,000 cubic yards) of petroleum waste, mostly acidic tarry sludge. The SS process was selected over competing methods because it afforded minimal volume increase, could readily achieve Record of Decision (ROD) specified physical and chemical treatment goals, could be implemented with treatment equipment that minimized emissions, and could be performed with low reagent usage and at low cost. To ensure treatment goals were achieved and an accelerated schedule met, a custom designed and fabricated transportable treatment unit (TTU) was employed to implement the process. The treated material was visually soil-like in character, it was left in stockpiles for periods of time, and it was placed and compacted in the on site landfill using standard earth-moving equipment

  6. Radiolytic and thermal generation of gases from Hanford grout samples

    Energy Technology Data Exchange (ETDEWEB)

    Meisel, D.; Jonah, C.D.; Kapoor, S.; Matheson, M.S.; Mulac, W.A.

    1993-10-01

    Gamma irradiation of WHC-supplied samples of grouted Tank 102-AP simulated nonradioactive waste has been carried out at three dose rates, 0.25, 0.63, and 130 krad/hr. The low dose rate corresponds to that in the actual grout vaults; with the high dose rate, doses equivalent to more than 40 years in the grout vault were achieved. An average G(H{sub 2}) = 0.047 molecules/100 eV was found, independent of dose rate. The rate of H2 production decreases above 80 Mrad. For other gases, G(N{sub 2}) = 0.12, G(O{sub 2}) = 0.026, G(N{sub 2}O) = 0.011 and G(CO) = 0.0042 at 130 krad/hr were determined. At lower dose rates, N{sub 2} and O{sub 2} could not be measured because of interference by trapped air. The value of G(H{sub 2}) is higher than expected, suggesting segregation of water from nitrate and nitrite salts in the grout. The total pressure generated by the radiolysis at 130 krad/h has been independently measured, and total amounts of gases generated were calculated from this measurement. Good agreement between this measurement and the sum of all the gases that were independently determined was obtained. Therefore, the individual gas measurements account for most of the major components that are generated by the radiolysis. At 90 {degree}C, H{sub 2}, N{sub 2}, and N{sub 2}O were generated at a rate that could be described by exponential formation of each of the gases. Gases measured at the lower temperatures were probably residual trapped gases. An as yet unknown product interfered with oxygen determinations at temperatures above ambient. The thermal results do not affect the radiolytic findings.

  7. Numerical Simulations of Settlement of Jet Grouting Columns

    Directory of Open Access Journals (Sweden)

    Juzwa Anna

    2016-03-01

    Full Text Available The paper presents the comparison of results of numerical analyses of interaction between group of jet grouting columns and subsoil. The analyses were conducted for single column and groups of three, seven and nine columns. The simulations are based on experimental research in real scale which were carried out by authors. The final goal for the research is an estimation of an influence of interaction between columns working in a group.

  8. The influence of clay drilling grout on the quality of well cementation

    Energy Technology Data Exchange (ETDEWEB)

    Romic, L; Martinko, B

    1979-01-01

    The influence of clay drilling grout on the behavior of the cement mixture during the cementing of casings is described. Experimental results are given which demonstrate that clay drill grout slows down the setting of the cement mixture, lowers the durability of cement stone and its adherence to the well's walls, and changes the rheological properties and viscosity of the cement mixture. Separating devices, which prevent the mixing of the clay drilling grout and the cement solutions during the cementation process, are recommended.

  9. Laboratory Evaluation of Underwater Grouting of CPP-603 Basins

    International Nuclear Information System (INIS)

    Johnson, V.J.; Pao, J.H.; Demmer, R.L.; Tripp, J.L.

    2002-01-01

    A project is underway to deactivate a Fuel Storage Basin. The project specifies the requirements and identifies the tasks that will be performed for deactivation of the CPP- 603 building at the Idaho Nuclear Technology and Engineering Center of the Idaho National Engineering and Environmental Laboratory. The Fuel Receiving and Storage Building (CPP- 603) was originally used to receive and store spent nuclear fuel from various facilities. The area to undergo deactivation includes the three spent nuclear fuel storage basins and a transfer canal (1.5 million gallons of water storage). Deactivation operations at the task site include management of the hot storage boxes and generic fuel objects, removal of the fuel storage racks, basin sludge, water evaporation and basin grouting, and interior equipment, tanks, and associated components. This includes a study to develop a grout formulation and placement process for this deactivation project. Water will be allowed to passively evaporate to r educe the spread of contamination from the walls of the basin. The basins will be filled with grout, underwater, as the water evaporates to maintain the basin water at a safe level. The objective of the deactivation project is to eliminate potential exposure to hazardous and radioactive materials and eliminate potential safety hazards associated with the CPP-603 building

  10. Improvement of Shear Strength of Sandy Soil by Cement Grout with Fly Ash

    Directory of Open Access Journals (Sweden)

    Haifaa Abdulrasool Ali

    2018-12-01

    Full Text Available The effects of the permeation cement grout with fly ash on the sandy soil skeleton were studied in the present work in two phase; first phase the shear strength parameters, and the second phase effect of these grouted materials on volume grouted zone by injection (51 cm³ of slurry in sandy soil placed in steel cylinder model with dimension 15 cm in diameter and 30 cm in height. The soil sample was obtained from Karbala city and it is classified as poorly graded sand (SP according to USCS. The soil samples were improved by cement grout with three percentages weight of water cement ratio (w:c; (0.1w:0.9c, 0.8w:0.2c, and 0.7w:0.3c, while the soil samples were dehydrated for one day curing time. Fly ash class (F was used with cement grout as filler material; it was added to the mixture as a replacement material for cement in weight percentages; 10%, 25% and 40%. According to the results of tests, both shear strength and approximate volume of the effective grouted zone for treated samples soil with cement grout was increased when the water cement ratio decreased. Fly ash with cement grout needs to increase the water demand for the grout mixing to give best results in both shear strength and filling the soil voids.

  11. Monitoring of Grouting Compactness in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

    Directory of Open Access Journals (Sweden)

    Tianyong Jiang

    2016-08-01

    Full Text Available A post-tensioning tendon duct filled with grout can effectively prevent corrosion of the reinforcement, maintain bonding behavior between the reinforcement and concrete, and enhance the load bearing capacity of concrete structures. In practice, grouting of the post-tensioning tendon ducts always causes quality problems, which may reduce structural integrity and service life, and even cause accidents. However, monitoring of the grouting compactness is still a challenge due to the invisibility of the grout in the duct during the grouting process. This paper presents a stress wave-based active sensing approach using piezoceramic transducers to monitor the grouting compactness in real time. A segment of a commercial tendon duct was used as research object in this study. One lead zirconate titanate (PZT piezoceramic transducer with marble protection, called a smart aggregate (SA, was bonded on the tendon and installed in the tendon duct. Two PZT patch sensors were mounted on the top outside surface of the duct, and one PZT patch sensor was bonded on the bottom outside surface of the tendon duct. In the active sensing approach, the SA was used as an actuator to generate a stress wave and the PZT sensors were utilized to detect the wave response. Cement or grout in the duct functions as a wave conduit, which can propagate the stress wave. If the cement or grout is not fully filled in the tendon duct, the top PZT sensors cannot receive much stress wave energy. The experimental procedures simulated four stages during the grout pouring process, which includes empty status, half grouting, 90% grouting, and full grouting of the duct. Experimental results show that the bottom PZT sensor can detect the signal when the grout level increases towards 50%, when a conduit between the SA and PZT sensor is formed. The top PZT sensors cannot receive any signal until the grout process is completely finished. The wavelet packet-based energy analysis was adopted in this

  12. Variability in properties of grouted Phosphate/Sulfate N-Reactor Waste

    International Nuclear Information System (INIS)

    Lokken, R.O.; Martin, P.F.C.; Bowen, W.M.; Harty, H.; Treat, R.L.

    1987-02-01

    A Transportable Grout Facility (TGF) is being constructed at the Hanford site in Washington State to convert various low-level liquid wastes to a grout waste form for onsite disposal. The TGF Project is managed by Rockwell Hanford Operations (Rockwell). Oak Ridge National Laboratory (ORNL) has provided a grout formulation for Phosphate/Sulfate N-Reactor Waste, the first waste stream scheduled for grouting beginning in late 1987. The formulation includes a blend of portland cement, fly ash, attapulgite clay, and an illitic clay. Grout will be produced by mixing the blend with Phosphate/Sulfate N-Reactor Waste. These wastes result from decontamination and ion-exchange regeneration activities at Hanford's N-Reactor. Pacific Northwest Laboratory (PNL) is conducting studies on grouted Phosphate/Sulfate N-Reactor Waste to verify that the grout can be successfully processed and, when hardened, that it will meet all performance and regulatory requirements. As part of these studies, PNL is assessing the variability that may be encountered when processing Phosphate/Sulfate N-Reactor Waste grout. Sources of variability that may affect grout properties include the composition and concentrations of the waste and dry solids, temperature, efficiency of dry solids blending, and dry blend storage time. 13 refs., 20 figs., 9 tabs

  13. Fixation of waste materials in grouts. Part II. An empirical equation for estimating compressive strength for grouts from different wastes

    International Nuclear Information System (INIS)

    Tallent, O.K.; McDaniel, E.W.; Godsey, T.T.

    1986-04-01

    Compressive strength data for grouts prepared from three different nuclear waste materials have been correlated. The wastes include ORNL low-level waste (LLW) solution, Hanford Facility Waste (HFW) solution, and Hanford cladding removal waste (CRW) slurry. Data for the three wastes can be represented with a 0.96 coefficient of correlation by the following equation: S = -9.56 + 9.27 D/I + 18.11/C + 0.010 R, where S denotess 28-d compressive strength, in mPa; D designates Waste concentration, fraction of the original; I is ionic strength; C denotes Attapulgite-150 clay content of dry blend, in wt %; and R is the mix ratio, kg/m 3 . The equation may be used to estimate 28-d compressive strengths of grouts prepared within the compositional range of this investigation

  14. Study on grout-filled coupling steel sleeve; Kokan sleeve wo mochiita grout jutenshiki tekkin tsugite ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y. [Osaka University, Osaka (Japan)

    1997-06-01

    Newly designed grout-filled coupling sleeve is discussed, which uses as the sleeve an electric resistance welded tube with protrusions formed in a checker pattern on its inner wall and is capable of using various premixed grouting materials available on the market. Specimens are subjected to uniaxial tensile loading and positive/negative cyclic loading, and the impact of various factors on the basic performance of the specimens and their stress/distortion characteristics at local spots in the reinforcing bar are disclosed. In the positive/negative cyclic loading in the plastic region, however, such findings are not obtained. In view of the stress/distortion characteristics at local spots in the reinforcing bar, a method is proposed for estimating the coupling strength and fracture type. A method for estimating the deformation behavior of the coupling, however, is not proposed. Investigations are conducted into the manufacture and installation of the grout holding framework, coupling fixing jigs, plugs, etc., and it is found that precasting should be studied in the future. 38 refs., 156 figs., 30 tabs.

  15. Phase stability and oxygen non-stoichiometry of SrCo0.8Fe0.2O3-d measured by in-situ neutron diffraction

    NARCIS (Netherlands)

    McIntosh, Steven; McIntosh, S.; Vente, Jaap F.; Haije, Wim G.; Blank, David H.A.; Bouwmeester, Henricus J.M.

    2006-01-01

    The phase stability, oxygen stoichiometry and expansion properties of SrCo0.8Fe0.2O3−δ (SCF) were determined by in situ neutron diffraction between 873 and 1173 K and oxygen partial pressures of 5×10−4 to 1 atm. At a pO2 of 1 atm, SCF adopts a cubic perovskite structure, space group Pm3¯m, across

  16. On the stability of a variety of organic photovoltaic devices by IPCE and in situ IPCE analyses - the ISOS-3 inter-laboratory collaboration

    OpenAIRE

    Terán-Escobar, Gerardo; Krebs, Frederik C.; Lira-Cantú, Mónica

    2012-01-01

    This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPV) devices prepared by leading research laboratories. All devices have been shipped to and degraded at RISempty set-DTU up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work, we apply the Incident Photon-to-Electron Conversion Efficiency (IPCE) and the in situ IPCE techniques to determin...

  17. Shining a light on Jarosite: formation, alteration and stability studies using in situ experimental synchrotron and neutron techniques.

    Science.gov (United States)

    Brand, H. E. A.; Scarlett, N. V. Y.; Wilson, S. A.; Frierdich, A. J.; Grey, I. E.

    2016-12-01

    Jarosites and related minerals are critical to a range of mineral processing and research applications. They are used in the removal of iron species from smelting processes; they occur in metal bioleaching systems, and they are present in acid mine drainage environments. There has been a recent resurgence in interest in jarosites since their detection on Mars. In this context, the presence of jarosite has been recognised as a likely indicator of liquid water at the surface of Mars in the past & it is thought that their study will provide insight into the environmental history of Mars. Acid sulfate soils cover large areas of the Australian coastline and are likely to be a major constituent of the Martian environment. The oxidation of acid sulfate soils, coupled with potential release of heavy metals and acidic groundwaters, can have serious consequences for fragile ecosystems. Understanding these sediments will provide insight into the biogeochemical processes that affect the lifetimes of transient mineral species on Earth, and may be used to better understand soil acidification, contaminant mobility at sites affected by acid and metalliferous drainage, and even constrain past weathering and putative biosignatures on Mars. Knowledge of the behaviour of jarosite minerals under the actual conditions that they are found in is crucial to understanding their potential environmental impacts on both Earth and Mars. To this end, we are engaged in a program to study the formation, stability and alteration of natural and synthetic jarosite minerals using a complementary suite of in situ synchrotron and neutron techniques. There are 3 sections to this work that will introduce the experimental techniques and sample environments that make these measurements possible: Studying the nucleation and growth of jarosites under laboratory conditions. The experimentation consisted of time-resolved synchrotron small angle X-ray scattering and X-ray diffraction. Studying the stability of

  18. Safety, efficacy, predictability and stability of laser in situ keratomileusis (LASIK) with a 1000-Hz scanning spot excimer laser.

    Science.gov (United States)

    Khoramnia, Ramin; Salgado, Josefina P; Wuellner, Christian; Donitzky, Christof; Lohmann, Chris P; Winkler von Mohrenfels, Christoph

    2012-09-01

    To evaluate the safety, efficacy, predictability and stability of laser in situ keratomileusis (LASIK) with a 1000-Hz scanning spot excimer laser (Concept System 1000; WaveLight GmbH, Erlangen, Germany). LASIK was performed on twenty eyes with myopia or myopic astigmatism (mean spherical equivalent refraction: -3.97±1.72 dioptres (D); mean cylinder: -0.84±0.77 D) using a microkeratome for flap creation and the Concept System 1000 for photoablation. Patients were examined preoperatively as well as 1, 3 and 6 months after the treatment. Manifest sphere and cylinder, uncorrected (UCDVA) and best corrected (BCDVA) distance visual acuity, corneal topography and pachymetry were analysed. We observed no adverse events that might have been associated with the use of a repetition rate of 1000 Hz. All eyes maintained or had improved BCDVA at 6 months after treatment when compared to preoperative values. Six months after LASIK, UCDVA was 20/20 or better in 85% and 20/25 or better in 100% of the eyes. The spherical equivalent refraction was within ±0.50 D in 95% of the eyes at 6 months after surgery. The refraction stayed stable over time; 95% of the eyes changedLASIK with the prototype 1000-Hz excimer laser was safe, efficient and predictable. The postoperative refraction was stable over time. There were no specific clinical side-effects that might be associated with the use of such a high repetition rate. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  19. Enhanced permanganate in situ chemical oxidation through MnO2 particle stabilization: evaluation in 1-D transport systems.

    Science.gov (United States)

    Crimi, Michelle; Quickel, Mark; Ko, Saebom

    2009-02-27

    In situ chemical oxidation using permanganate is an increasingly employed approach to organic contaminant remediation at hazardous waste sites. Manganese dioxide (MnO2) particles form as a by-product of the reaction of permanganate with contaminants and naturally-reduced subsurface materials. These particles are of interest because they have the potential to deposit in the subsurface and impact the flow regime in/around permanganate injection, including the well screen, filter pack, and the surrounding subsurface formation. Control of these particles can allow for improved oxidant injection and transport, and contact between the oxidant and contaminants of concern. Sodium hexametaphosphate (HMP) has previously been identified as a promising aid to stabilize MnO2 in solution when included in the oxidizing solution, increasing the potential to inhibit particle deposition and impact subsurface flow. The goal of the experimental studies described herein was to investigate the ability of HMP to prevent particle deposition in transport studies using four different types of porous media. Permanganate was delivered to a contaminant source zone (trichloroethylene) located within four different media types with variations in sand, clay, organic carbon, and iron oxides (as goethite) content. Deposition of MnO2 within the columns was quantified with distance from the source zone. Experiments were repeated in replicate columns with the inclusion of HMP directly with the oxidant delivery solution, and MnO2 deposition was again quantified. While total MnO2 deposition within the 60 cm columns did not change significantly with the addition of HMP, deposition within the contaminant source zone decreased by 25-85%, depending on the specific media type. The greatest differences in deposition were observed in the goethite-containing and clay-containing columns. Columns containing these two media types experienced completely plugged flow in the oxidant-only delivery systems; however

  20. In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag.

    Science.gov (United States)

    Negim, Osama; Mench, Michel; Bes, Clémence; Motelica-Heino, Mikael; Amin, Fouad; Huneau, Frédéric; Le Coustumer, Philippe

    2012-03-01

    A former wood exploitation revealing high Cu and As concentration of the soils served as a case study for assisted phytoextraction. P-spiked Linz-Donawitz (LD) slag was used as a soil additive to improve physico-chemical soil properties and in situ stabilize Cu and other trace metals in a sandy Cu-contaminated soil (630 mg kg⁻¹ soil). The LD slag was incorporated into the contaminated soil to consist four treatments: 0% (T1), 1% (T2), 2% (T3), and 4% (T4). A similar uncontaminated soil was used as a control (CTRL). After a 1-month reaction period, potted soils were used for a 2-week growth experiment with dwarf beans. Soil pH increased with the incorporation rate of LD slag. Similarly the soil electrical conductivity (EC, in millisiemens per centimetre) is ameliorated. Bean plants grown on the untreated soil (T1) showed a high phytotoxicity. All incorporation rates of LD slag increased the root and shoot dry weight yields compared to the T1. The foliar Ca concentration of beans was enhanced for all LD slag-amended soil, while the foliar Mg, K, and P concentrations were not increased. Foliar Cu, Zn, and Cr concentrations of beans decreased with the LD slag incorporation rate. P-spiked LD slag incorporation into polluted soil allow the bean growth and foliar Ca concentration, but also to reduce foliar Cu concentration below its upper critical value avoiding an excessive soil EC and Zn deficiency. This dual effect can be of interest for soil remediation at larger scale.

  1. R20 Programme: Grout setting and strength development in ONKALO. Literature review, observations and experiments

    International Nuclear Information System (INIS)

    Karttunen, P.; Raivio, P.

    2008-12-01

    ONKALO is an underground rock characterisation facility planned to be a part of nuclear waste repository in future. ONKALO is located in Olkiluoto Finland. Posiva Oy owned by Teollisuuden Voima Oy and Fortum Power and Heat Oy is responsible for the repository, research, construction and use of the ONKALO and closing of the underground facility after use. During construction of ONKALO it has been observed that the setting and strength of grouting materials have not sporadically developed as expected (in ONKALO). The phenomenon has been observed for the first time in the year 2005. The observations examined in this report are made in the grouting field tests and in ordinary grouting during the year 2007. The phenomenon has been observed with low pH and standard grouts and bolt grouting mortars. The reasons for this phenomenon are studied based on literature review, observations and tests in the field and laboratory. The effect of reactions between groundwater and grout, the effect of the raw materials as well as curing conditions, temperature and pressure are studied. There are several potential factors that can cause observed phenomenon. Some factors are more probable than others. Laboratory experiments for the samples of poor strength development were done. These samples were taken from the grouting holes or packers in which the strength of the grout was not developed as expected. The results of these experiments were compared to the results gained from the samples cast from the same grout batches and cured in the tunnel conditions. The purpose was to find out the factor causing slow strength development of the grouted mixes. One single reason, which can slow the setting of the grouts in ONKALO is the low temperature in the rock, but the temperature cannot cause the phenomenon alone. Locally groundwater contains compounds that can create chemically aggressive environment for (the Portland) cement based grouts. The groundwater chemistry in ONKALO has not been proved

  2. Evaluation of final waste forms and recommendations for baseline alternatives to grout and glass

    International Nuclear Information System (INIS)

    Bleier, A.

    1997-09-01

    An assessment of final waste forms was made as part of the Federal Facilities Compliance Agreement/Development, Demonstration, Testing, and Evaluation (FFCA/DDT ampersand E) Program because supplemental waste-form technologies are needed for the hazardous, radioactive, and mixed wastes of concern to the Department of Energy and the problematic wastes on the Oak Ridge Reservation. The principal objective was to identify a primary waste-form candidate as an alternative to grout (cement) and glass. The effort principally comprised a literature search, the goal of which was to establish a knowledge base regarding four areas: (1) the waste-form technologies based on grout and glass, (2) candidate alternatives, (3) the wastes that need to be immobilized, and (4) the technical and regulatory constraints on the waste-from technologies. This report serves, in part, to meet this goal. Six families of materials emerged as relevant; inorganic, organic, vitrified, devitrified, ceramic, and metallic matrices. Multiple members of each family were assessed, emphasizing the materials-oriented factors and accounting for the fact that the two most prevalent types of wastes for the FFCA/DDT ampersand E Program are aqueous liquids and inorganic sludges and solids. Presently, no individual matrix is sufficiently developed to permit its immediate implementation as a baseline alternative. Three thermoplastic materials, sulfur-polymer cement (inorganic), bitumen (organic), and polyethylene (organic), are the most technologically developed candidates. Each warrants further study, emphasizing the engineering and economic factors, but each also has limitations that regulate it to a status of short-term alternative. The crystallinity and flexible processing of sulfur provide sulfur-polymer cement with the highest potential for short-term success via encapsulation. Long-term immobilization demands chemical stabilization, which the thermoplastic matrices do not offer. Among the properties of the

  3. Use Of Cementitious Materials For SRS Reactor Facility In-Situ Decommissioning - 11620

    International Nuclear Information System (INIS)

    Langton, C.; Stefanko, D.; Serrato, M.; Blankenship, J.; Griffin, W.; Waymer, J.; Matheny, D.; Singh, D.

    2010-01-01

    The United States Department of Energy (US DOE) concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., producing (reactor facilities), processing (isotope separation facilities) or storing radioactive materials. The Savannah River Site 105-P and 105-R Reactor Facility ISD requires about 250,000 cubic yards of grout to fill the below grade structure. The fills are designed to prevent subsidence, reduce water infiltration, and isolate contaminated materials. This work is being performed as a Comprehensive Environmental Response, Compensations and Liability Act (CERCLA) action and is part of the overall soil and groundwater completion projects for P- and R-Areas. Cementitious materials were designed for the following applications: (1) Below grade massive voids/rooms: Portland cement-based structural flowable fills for - Bulk filling, Restricted placement and Underwater placement. (2) Special below grade applications for reduced load bearing capacity needs: Cellular portland cement lightweight fill (3) Reactor vessel fills that are compatible with reactive metal (aluminum metal) components in the reactor vessels: Calcium sulfoaluminate flowable fill, and Magnesium potassium phosphate flowable fill. (4) Caps to prevent water infiltration and intrusion into areas with the highest levels of radionuclides: Portland cement based shrinkage compensating concrete. A system engineering approach was used to identify functions and requirements of the fill and capping materials. Laboratory testing was performed to identify candidate formulations and develop final design mixes. Scale-up testing was performed to verify material production and placement as well as fresh and cured properties. The 105-P and 105-R ISD projects are currently in progress and are expected to be complete in 2012. The focus of this paper is to describe the (1) grout mixes

  4. USE OF CEMENTITIOUS MATERIALS FOR SRS REACTOR FACILITY IN-SITU DECOMMISSIONING - 11620

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Stefanko, D.; Serrato, M.; Blankenship, J.; Griffin, W.; Waymer, J.; Matheny, D.; Singh, D.

    2010-12-07

    The United States Department of Energy (US DOE) concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., producing (reactor facilities), processing (isotope separation facilities) or storing radioactive materials. The Savannah River Site 105-P and 105-R Reactor Facility ISD requires about 250,000 cubic yards of grout to fill the below grade structure. The fills are designed to prevent subsidence, reduce water infiltration, and isolate contaminated materials. This work is being performed as a Comprehensive Environmental Response, Compensations and Liability Act (CERCLA) action and is part of the overall soil and groundwater completion projects for P- and R-Areas. Cementitious materials were designed for the following applications: (1) Below grade massive voids/rooms: Portland cement-based structural flowable fills for - Bulk filling, Restricted placement and Underwater placement. (2) Special below grade applications for reduced load bearing capacity needs: Cellular portland cement lightweight fill (3) Reactor vessel fills that are compatible with reactive metal (aluminum metal) components in the reactor vessels: Calcium sulfoaluminate flowable fill, and Magnesium potassium phosphate flowable fill. (4) Caps to prevent water infiltration and intrusion into areas with the highest levels of radionuclides: Portland cement based shrinkage compensating concrete. A system engineering approach was used to identify functions and requirements of the fill and capping materials. Laboratory testing was performed to identify candidate formulations and develop final design mixes. Scale-up testing was performed to verify material production and placement as well as fresh and cured properties. The 105-P and 105-R ISD projects are currently in progress and are expected to be complete in 2012. The focus of this paper is to describe the (1) grout mixes

  5. In situ enhanced soil mixing. Innovative technology summary report

    International Nuclear Information System (INIS)

    1996-02-01

    In Situ Enhanced Soil Mixing (ISESM) is a treatment technology that has been demonstrated and deployed to remediate soils contaminated with volatile organic compounds (VOCs). The technology has been developed by industry and has been demonstrated with the assistance of the U.S. Department of Energy's Office of Science and Technology and the Office of Environmental Restoration. The technology is particularly suited to shallow applications, above the water table, but can be used at greater depths. ISESM technologies demonstrated for this project include: (1) Soil mixing with vapor extraction combined with ambient air injection. [Contaminated soil is mixed with ambient air to vaporize volatile organic compounds (VOCs). The mixing auger is moved up and down to assist in removal of contaminated vapors. The vapors are collected in a shroud covering the treatment area and run through a treatment unit containing a carbon filter or a catalytic oxidation unit with a wet scrubber system and a high efficiency particulate air (HEPA) filter.] (2) soil mixing with vapor extraction combined with hot air injection [This process is the same as the ambient air injection except that hot air or steam is injected.] (3) soil mixing with hydrogen peroxide injection [Contaminated soil is mixed with ambient air that contains a mist of diluted hydrogen peroxide (H 2 O 2 ) solution. The H 2 O 2 solution chemically oxidizes the VOCs to carbon dioxide (CO 2 ) and water.] (4) soil mixing with grout injection for solidification/stabilization [Contaminated soil is mixed as a cement grout is injected under pressure to solidify and immobilize the contaminated soil in a concrete-like form.] The soils are mixed with a single-blade auger or with a combination of augers ranging in diameter from 3 to 12 feet

  6. An Experimental Study of Portland Cement and Superfine Cement Slurry Grouting in Loose Sand and Sandy Soil

    OpenAIRE

    Weijing Yao; Jianyong Pang; Yushan Liu

    2018-01-01

    Grouting technology is widely applied in the fields of geotechnical engineering in infrastructure. Loose sand and sandy soil are common poor soils in tunnel and foundation treatments. It is necessary to use superfine cement slurry grouting in the micro-cracks of soil. The different effectiveness of Portland cement slurry and superfine cement slurry in sandy soil by the laboratory grouting experiment method were presented in this paper. The grouting situations of superfine cement slurry inject...

  7. THERMALLY CONDUCTIVE CEMENTITIOUS GROUTS FOR GEOTHERMAL HEAT PUMPS. PROGRESS REPORT BY 1998

    Energy Technology Data Exchange (ETDEWEB)

    ALLAN,M.L.; PHILIPPACOPOULOS,A.J.

    1998-11-01

    Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98.

  8. Rock mass joint treated by jet grouting at Diavik A418 dike south abutment

    Energy Technology Data Exchange (ETDEWEB)

    Baisre, C.A. [SNC-Lavalin, Montreal, PQ (Canada); Hatch Energy, Montreal, PQ (Canada)

    2009-07-01

    In order to exploit the diamond pipes at the Diavik mines, located in the Northwest Territories, two dikes were built into the Lac de Gras, dikes A154 and A418. However, during the construction of the curtain grouting of the A418 Dike, the pressure grouting technique did not achieve the desired closure of a subhorizontal joint located at variable depth beneath the dike foundation into the granite rock mass at the south abutment. The joint was filled mainly with silt, sand and gravel. This paper reviewed the problems with the pressure grouting treatment methodology, and the final decision of the designers and construction manager to treat the joint by jet grouting. The paper outlined pressure grouting, with particular reference to technical specifications; curtain grouting analysis; and joint grouting investigation. The joint treatment by jet grouting was described and the most important features of the core drilling after jetting were outlined. The permeability of the joint was reduced significantly in the treated area, according to observations made during jetting and in the recovered cores and the permeability tests. 1 tab., 7 figs.

  9. Durability of double-shell slurry feed grouts: FY-90 results

    International Nuclear Information System (INIS)

    Lokken, R.O.; Martin, P.F.C.

    1992-12-01

    Plans for disposal of the low-level fraction of selected double-shell tank wastes at Hanford include grouting. Grout disposal is the process of mixing low-level liquid waste with cementitious powders and pumping the slurry to near-surface, underground concrete vaults; hydration results in the formation of a solid product that binds/encapsulates the radioactive/hazardous constituents. In this durability program, previous studies have indicated a strong impact from curing temperature/time on strength and leach resistance of DSSF grouts. The current studies were expanded to determine whether these impacts could be attributed to other factors, such as dry blend composition and waste concentration. Major conclusions: grouts from dry blends with 40 wt% limestone had lower strengths; compressive strengths and leach resistance decreased with increased curing temperature/time; leach resistance increased for grouts prepared with dilute DSSF; nitrate leach resistance increased with high slag/cement ratios, dilute DSSF, and low curing temperatures; amount of drainable liquids for grouts using diluted DSSF was lowest when slag content was high; the 2 most significant factors affecting grout properties were the slag/cement ratio and waste dilution (slag-waste reactions appear to dominate the properties of DSSF grouts)

  10. Geochemical modelling of grout-groundwater-rock interactions at the seal-rock interface

    International Nuclear Information System (INIS)

    Alcorn, S.; Christian-Frear, T.

    1992-02-01

    Theoretical investigations into the longevity of repository seals have dealt primarily with the development of a methodology to evaluate interactions between portland cement-based grout and groundwater. Evaluation of chemical thermodynamic equilibria among grout, groundwater, and granitic host rock phases using the geochemical codes EQ3NR/EQ6 suggests that a fracture filled with grout and saturated with groundwater will tend to fill and 'tighten' with time. These calculations predict that some grout and rock phases will dissolve, and that there will be precipitation of secondary phases which collectively have a larger overall volume than that of the material dissolved. Model assumptions include sealing of the fracture in a sluggish hydrologic regime (low gradient) characterized by a saline groundwater environment. The results of the calculations suggest that buffering of the fracture seals chemical system by the granitic rock may be important in determining the long-term fate of grout seals and the resulting phase assemblage in the fracture. The similarity of the predicted reaction product phases to those observed in naturally filled fractures suggests that with time equilibrium will be approached and grouted fractures subject to low hydrologic gradients will continue to seal. If grout injected into fractures materially reduces groundwater flux, the approach to chemical equilibrium will likely be accelerated. In light of this, even very thin or imperfectly grouted fractures would tighten in suitable hydrogeologic environments. In order to determine the period of time necessary to approach equilibrium, data on reaction rates are required. (au)

  11. Mixing conditions in application of bentonite grouting to radioactive waste disposal

    International Nuclear Information System (INIS)

    Kobayakawa, Hiroaki; Ito, Hiroshi

    2007-01-01

    The purpose of this study was to understand the flow properties and permeability of bentonite grout with NaCl added, using laboratory tests, and to clarify the mixing conditions of bentonite as a material. Given that the required permeability of clay grout is 10 -9 (m/s), the combination of grout (W/B) becomes 6 or less. The viscosity of the grout was measured, and because the viscosity was higher than the thickest cement milk on dam grouting, it was found that grout with a W/B of less than 10 was difficult to inject into rock joints. We then added NaCl to grout with a W/B is 6, and its viscosity decreased as the amount of NaCl increased. A grout of viscosity able to be injected into rock joints was achieved by adding NaCl in a density higher than 'W:NaCl=40:1'. Next, the permeability of a bentonite suspension with NaCl was examined using the falling head permeability test. Testing the sample 'B:W:NaCl=20:20:1' for 10 days revealed that the initial permeability 10 -8 (m/s) decreased to 10 -10 - 10 -11 (m/s). These results showed that a suspension to inject into rock joints could be made by adding NaCl, and clarified that permeation of groundwater into the suspension causes a decline in permeability. (author)

  12. Examination of sample of grout after 63 years exposure underground. Technical report

    International Nuclear Information System (INIS)

    Rhoderick, J.E.

    1981-05-01

    During an investigation of the Troy Lock and Dam, New York, a core was recovered that contained part of a metal anchor that had been grouted into foundation rock. Since this grout was about 63 years old and had presumably been continuously below the water table, it provided an opportunity to study the effect of this environment for this period of time on the phase composition and microstructure of this grout. The phase composition of the grout was studied by x-ray diffraction; its microstructure was studied by scanning electron microscopy. It was found that the grout had a normal composition and microstructure; the environmental conditions had not had a significant effect on either composition or microstructure. The original water content had been fairly high as would be expected

  13. Development testing of grouting and liner technology for humid sites

    International Nuclear Information System (INIS)

    Vaughan, N.D.

    1981-01-01

    Shallow land burial, although practiced for many years, has not always secured radionuclides from the biosphere in humid environments. To develop and demonstrate improved burial technology the Engineered Test Facility was implemented. An integral part of this experiment was site characterization, with geologic and hydrologic factors as major the components. Improved techniques for burial of low-level waste were developed and tested in the laboratory before being applied in the field. The two techniques studied were membrane trench liner and grouting void spaces

  14. Analysis of Anchoring Mechanism of Fully Grouted Prestressed Anchor

    Directory of Open Access Journals (Sweden)

    WEN Zhi-jie

    2014-01-01

    Full Text Available Some researchers have been carried out on analysis of the influence of the full grouted prestressed anchor shape of borehole wall on its carrying capacity. Based on the self-affine fractal feature of anchor borehole wall structural plane, the relation equation among structural plane shear strength, liquid injection pressure, tensile load and structural plane fractal dimension D was built, the instability judgment criterion of anchoring bearing strata and rock structural plane was determined, the solving equations of disintegrated rock support density were derived. Based on the experimental results, the theoretical basis of support design under the disintegrated rock condition was offered.

  15. Gamma irradiation test report of simulated grout specimens for gas generation/liquid advection

    International Nuclear Information System (INIS)

    Hinman, C.A.

    1994-01-01

    This report presents the results from an irradiation test performed on four specimens of grout that were fabricated from synthetic Double Shell Slurry Feed (DSSF) liquid waste. The objective was to investigate the radiolytic generation of gases and the potential for advective rejection of waste liquids from the grout matrix and to provide experimental information for the validation of the C-Cubed calculated model. It has been demonstrated that a number of gases can be formed within the grout due to radiolytic decomposition of various chemical components that make up the grout. This observation leads to the conjecture that the potential exists for the rejection of a portion of the 60 vol% free liquid from the grout matrix driven by pressurization by these gases. It was found that, for the specimen geometries used in this test series, and for peak radiation dose accumulation rates on the order of 4 to 60 times of the initial rate expected in the grout vaults (300 Rads/hr), no liquid rejection was observed from 2% to 35% of the target exposure expected in the grout vaults (1E+08 Rads). When the irradiation rate exceeded the projected grout vault dose rate by a factor of 200 a small amount of liquid rejection was observed from one of two specimens that had received 20% more than the goal exposure. Because of the differences in the magnitudes of the relative radiation field strengths between this study and an actual grout vault, it is concluded that the potential for liquid rejection by internal gas pressurization from presently configured grout waste forms is very low for the expected conditions

  16. Impact of In Situ Stress Distribution Characteristics on Jointed Surrounding Rock Mass Stability of an Underground Cavern near a Hillslope Surface

    Directory of Open Access Journals (Sweden)

    Bangxiang Li

    2017-01-01

    Full Text Available In this paper, a series of numerical simulations are performed to analyze the in situ stress distribution characteristics of the rock mass near different slope angles hillslope surfaces, which are subjected to the vertical gravity stress and different horizontal lateral stresses and the influence which the in situ stress distribution characteristics of 45° hillslope to the integral stability of surrounding rock mass when an underground cavern is excavated considering three different horizontal distances from the underground cavern to the slope surface. It can be concluded from the numerical results that different slope angles and horizontal lateral stresses have a strong impact on the in situ stress distribution and the integral surrounding rock mass stability of the underground cavern when the horizontal distance from the underground cavern to the slope surface is approximately 100 m to 200 m. The relevant results would provide some important constructive suggestions to the engineering site selection and optimization of large-scale underground caverns in hydropower stations.

  17. Combining in situ chemical oxidation, stabilization, and anaerobic bioremediation in a single application to reduce contaminant mass and leachability in soil.

    Science.gov (United States)

    Cassidy, Daniel P; Srivastava, Vipul J; Dombrowski, Frank J; Lingle, James W

    2015-10-30

    Laboratory batch reactors were maintained for 32 weeks to test the potential for an in situ remedy that combines chemical oxidation, stabilization, and anaerobic bioremediation in a single application to treat soil from a manufactured gas plant, contaminated with polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Portland cement and slaked lime were used to activate the persulfate and to stabilize/encapsulate the contaminants that were not chemically oxidized. Native sulfate-reducing bacteria degraded residual contaminants using the sulfate left after persulfate activation. The ability of the combined remedy to reduce contaminant mass and leachability was compared with NaOH-activated persulfate, stabilization, and sulfate-reducing bioremediation as stand-alone technologies. The stabilization amendments increased pH and temperature sufficiently to activate the persulfate within 1 week. Activation with both stabilization amendments and NaOH removed between 55% and 70% of PAH and BTEX. However, combined persulfate and stabilization significantly reduced the leachability of residual BTEX and PAH compared with NaOH activation. Sulfide, 2-naphthoic acid, and the abundance of subunit A of the dissimilatory sulfite reductase gene (dsrA) were used to monitor native sulfate-reducing bacteria, which were negatively impacted by activated persulfate, but recovered completely within weeks. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Hanford grout disposal program - an environmentally sound alternative

    International Nuclear Information System (INIS)

    Bergman, T.B.; Allison, J.M.

    1987-01-01

    The Hanford Grout Disposal Program (HGDP) is a comprehensive, integrated program to develop technology and facilities for the disposal of ∼ 3.0 x 10 5 m 3 (80 million gal) of the low-level fraction of liquid radioactive tank wastes at the Hanford site in southeastern Washington state. Environmentally sound disposal via long-term protection of the public and the environment is the principal goal of the HGDP. To accomplish this goal, several criteria have been established that guide technology and facility development activities. The key criteria are discussed. To meet the challenges posed by disposal of these wastes, the HGDP is developing a waste form using grout-forming materials, such as blast furnace slag, fly ash, clays, and Portland cement for solidification and immobilization of both the radioactive and hazardous chemical constituents. In addition to development of a final waste form, the HGDP is also developing a unique disposal system to assure long-term protection of the public and the environment. Disposal of a low-level nonhazardous waste will be initiated, as a demonstration of the disposal system concept, in June 1988. Disposal of higher activity hazardous wastes is scheduled to begin in October 1989

  19. Influence of in situ synthesized TiC on thermal stability and corrosion behavior of Zr60Cu10Al15Ni15 amorphous composites

    International Nuclear Information System (INIS)

    Geng, Jiwei; Teng, Xinying; Zhou, Guorong; Leng, Jinfeng; Zhao, Degang

    2014-01-01

    In situ synthesized TiC particles were prepared by a thermal explosion method. Adding “in situ synthesized” TiC into Zr 60 Cu 10 Al 15 Ni 15 glass matrix to obtain amorphous matrix composites was achieved. The corrosion behavior of Zr 60 Cu 10 Al 15 Ni 15 amorphous composites was evaluated using potentiodynamic polarization measurements in 3.5 wt% NaCl solution at room temperature. The results show that the microhardness and thermal stability are improved apparently, while the TiC (≤0.6 wt%) does not significantly affect the supercooled liquid behavior. Moreover, the corrosion resistance is improved apparently because the nanocrystals accelerate the diffusion of passive elements for faster formation of the protective passive film at nanocrystals/amorphous interfaces. However, when the TiC content is more than 0.6 wt%, both glass forming ability and corrosion resistance are reduced significantly

  20. On the stability of a variety of organic photovoltaic devices by IPCE and in situ IPCE analyses--the ISOS-3 inter-laboratory collaboration.

    Science.gov (United States)

    Teran-Escobar, Gerardo; Tanenbaum, David M; Voroshazi, Eszter; Hermenau, Martin; Norrman, Kion; Lloyd, Matthew T; Galagan, Yulia; Zimmermann, Birger; Hösel, Markus; Dam, Henrik F; Jørgensen, Mikkel; Gevorgyan, Suren; Kudret, Suleyman; Maes, Wouter; Lutsen, Laurence; Vanderzande, Dirk; Würfel, Uli; Andriessen, Ronn; Rösch, Roland; Hoppe, Harald; Rivaton, Agnès; Uzunoğlu, Gülşah Y; Germack, David; Andreasen, Birgitta; Madsen, Morten V; Bundgaard, Eva; Krebs, Frederik C; Lira-Cantu, Monica

    2012-09-07

    This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPV) devices prepared by leading research laboratories. All devices have been shipped to and degraded at RISØ-DTU up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work, we apply the Incident Photon-to-Electron Conversion Efficiency (IPCE) and the in situ IPCE techniques to determine the relation between solar cell performance and solar cell stability. Different ageing conditions were considered: accelerated full sun simulation, low level indoor fluorescent lighting and dark storage. The devices were also monitored under conditions of ambient and inert (N(2)) atmospheres, which allows for the identification of the solar cell materials more susceptible to degradation by ambient air (oxygen and moisture). The different OPVs configurations permitted the study of the intrinsic stability of the devices depending on: two different ITO-replacement alternatives, two different hole extraction layers (PEDOT:PSS and MoO(3)), and two different P3HT-based polymers. The response of un-encapsulated devices to ambient atmosphere offered insight into the importance of moisture in solar cell performance. Our results demonstrate that the IPCE and the in situ IPCE techniques are valuable analytical methods to understand device degradation and solar cell lifetime.

  1. Trace Metals in Groundwater and the Vadose Zone Calcite: In Situ Containment and Stabilization of Strontium-90 and Other Divalent Metals and Radionuclides at Arid West DOE

    International Nuclear Information System (INIS)

    Smith, Robert W.

    2004-01-01

    Radionuclide and metal contaminants such as strontium-90 are present beneath U.S. Department of Energy (DOE) lands in both the groundwater (e.g., 100-N area at Hanford, WA) and vadose zone (e.g., Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory). In situ containment and stabilization of these contaminants is a cost-effective treatment strategy. However, implementing in situ containment and stabilization approaches requires definition of the mechanisms that control contaminant sequestration. We are investigating the in situ immobilization of radionuclides or contaminant metals (e.g., strontium-90) by their facilitated co-precipitation with calcium carbonate in groundwater and vadose zone systems. Our facilitated approach, shown schematically in Figure 1, relies upon the hydrolysis of introduced urea to cause the acceleration of calcium carbonate precipitation (and trace metal co-precipitation) by increasing pH and alkalinity. Subsurface urea hydrolysis is catalyzed by the urease enzyme, which may be either introduced with the urea or produced in situ by ubiquitous subsurface urea hydrolyzing microorganisms. Because the precipitation process tends to be irreversible and many western aquifers are saturated with respect to calcite, the co-precipitated metals and radionuclides will be effectively removed from the aqueous phase over the long-term. Another advantage of the ureolysis approach is that the ammonium ions produced by the reaction can exchange with radionuclides sorbed to subsurface minerals, thereby enhancing the availability of the radionuclides for re-capture in a more stable solid phase (co-precipitation rather than adsorption)

  2. Long-term degradation (or improvement?) of cementitious grout/concrete for waste disposal at Hanford

    International Nuclear Information System (INIS)

    Piepho, M.G.

    1997-01-01

    If grout and/or concrete barriers and containments are considered for long-term (500 yrs to 100,000 ) waste disposal, then long-term degradation of grout/cement materials (and others) need to be studied. Long-term degradations of a cementitious grout monolith (15.4mW x 10.4mH x 37.6mL) and its containment concrete shell and asphalt shell (each 1-m thick) were analyzed. The main degradation process of the concrete shell was believed to be fractures due to construction joints, shrinkage, thermal stress, settlement, and seismic events. A scenario with fractures was modeled (flow and transport model) for long-term risk performance (out to a million yrs). Even though the concrete/grout is expected to fracture, the concrete/grout chemistry, which has high Ph value, is very beneficial in causing calcite deposits from calcium in the water precipitating in the fractures. These calcite deposits will tend to plug the fracture and keep water from entering. The effectiveness of such plugging needs to be studied more. It's possible that the plugged fractures are more impermeable than the original concrete/grout. The long-term performance of concrete/grout barriers will be determined by its chemistry, not its mechanical properties

  3. Acute toxicity screening of Hanford Site waste grouts using aquatic invertebrates

    International Nuclear Information System (INIS)

    Rebagay, T.V.; Dodd, D.A.; Lockrem, L.L.; Voogd, J.A.

    1993-01-01

    Liquid wastes containing radioactive, hazardous, and regulated chemicals have been generated throughout the 50 years operation of the Hanford Site of the US Department of Energy near Richland, Washington. The current strategy for the disposal of the low-level radioactive portion of these wastes involves immobilization of the waste in the form of grout. Because the potential risk of animal and plant exposure to grouts is unknown, acute toxicity screening of grouts is needed. Grouts were prepared by mixing a surrogate nonradioactive liquid waste with a blend consisting of cement, fly ash, and clay. Aqueous extracts of the grout were then screened for acute toxicity using aquatic invertebrates as test organisms and a fluorogenic substrate as the toxic stress indicator. After a 1-hour exposure of juvenile daphnids (D, magna, D. pulex, and C. dubia) to the grout extracts followed by a 15-minute reaction with the fluorogenic substrate, the degree of in vivo enzymatic inhibition was measured by the number of resulting fluorescent daphnids. The EC50 values calculated by probit analysis were 2,877 mg/L, 2,983 mg/L, and 3,174 mg/L for D. pulex, D. magna, and C. dubia, respectively. The slight difference in the responses may be attributed to the subjective pass-fail scoring of the fluorescence criterion. The results indicated that the grout studied is nonhazardous and nondangerous

  4. Thermally conductive cementitious grouts for geothermal heat pumps. Progress report FY 1998

    Energy Technology Data Exchange (ETDEWEB)

    Allan, M.L.; Philippacopoulos, A.J.

    1998-11-01

    Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98. The developed thermally conductive grout consists of cement, water, a particular grade of silica sand, superplasticizer and a small amount of bentonite. While the primary function of the grout is to facilitate heat transfer between the U-loop and surrounding formation, it is also essential that the grout act as an effective borehole sealant. Two types of permeability (hydraulic conductivity) tests was conducted to evaluate the sealing performance of the cement-sand grout. Additional properties of the proposed grout that were investigated include bleeding, shrinkage, bond strength, freeze-thaw durability, compressive, flexural and tensile strengths, elastic modulus, Poisson`s ratio and ultrasonic pulse velocity.

  5. A new method for real-time monitoring of grout spread through fractured rocks

    International Nuclear Information System (INIS)

    Henderson, A. E.; Robertson, I. A.; Whitfield, J. M.; Garrard, G. F. G.; Swannell, N. G.; Fisch, H.

    2008-01-01

    Reducing water ingress into the Shaft at Dounreay is essential for the success of future intermediate level waste (ILW) recovery using the dry retrieval method. The reduction is being realised by forming an engineered barrier of ultrafine cementitious grout injected into the fractured rock surrounding the Shaft. Grout penetration of 6 m in <50μm fractures is being reliably achieved, with a pattern of repeated injections ultimately reducing rock mass permeability by up to three orders of magnitude. An extensive field trials period, involving over 200 grout mix designs and the construction of a full scale demonstration barrier, has yielded several new field techniques that improve the quality and reliability of cementitious grout injection for engineered barriers. In particular, a new method has been developed for tracking in real-time the spread of ultrafine cementitious grout through fractured rock and relating the injection characteristics to barrier design. Fieldwork by the multi-disciplinary international team included developing the injection and real-time monitoring techniques, pre- and post injection hydro-geological testing to quantify the magnitude and extent of changes in rock mass permeability, and correlation of grout spread with injection parameters to inform the main works grouting programme. (authors)

  6. Laboratory leach tests of phosphate/sulfate waste grout and leachate adsorption tests using Hanford sediment

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R.J.; Martin, W.J.; McLaurine, S.B.; Airhart, S.P.; LeGore, V.L.; Treat, R.L.

    1987-12-01

    An assessment of the long-term risks posed by grout disposal at Hanford requires data on the ability of grout to resist leaching of waste species contained in the grout via contact with water that percolates through the ground. Additionally, data are needed on the ability of Hanford sediment (soil) surrounding the grout and concrete vault to retard migration of any wastes released from the grout. This report describes specific laboratory experiments that are producing empirical leach rate data and leachate-sediment adsorption data for Phosphate-Sulfate Waste (PSW) grout. The leach rate and adsorption values serve as inputs to computer codes used to forecast potential risk resulting from the use of ground water containing leached species. In addition, the report discusses other chemical analyses and geochemical computer code calculations that were used to identify mechanisms that control leach rates and adsorption potential. Knowledge of the controlling chemical and physical processes provides technical defensibility for using the empirical laboratory data to extrapolate the performance of the actual grout disposal system to the long time periods of interest. 59 refs., 83 figs., 18 tabs.

  7. Laboratory leach tests of phosphate/sulfate waste grout and leachate adsorption tests using Hanford sediment

    International Nuclear Information System (INIS)

    Serne, R.J.; Martin, W.J.; McLaurine, S.B.; Airhart, S.P.; LeGore, V.L.; Treat, R.L.

    1987-12-01

    An assessment of the long-term risks posed by grout disposal at Hanford requires data on the ability of grout to resist leaching of waste species contained in the grout via contact with water that percolates through the ground. Additionally, data are needed on the ability of Hanford sediment (soil) surrounding the grout and concrete vault to retard migration of any wastes released from the grout. This report describes specific laboratory experiments that are producing empirical leach rate data and leachate-sediment adsorption data for Phosphate-Sulfate Waste (PSW) grout. The leach rate and adsorption values serve as inputs to computer codes used to forecast potential risk resulting from the use of ground water containing leached species. In addition, the report discusses other chemical analyses and geochemical computer code calculations that were used to identify mechanisms that control leach rates and adsorption potential. Knowledge of the controlling chemical and physical processes provides technical defensibility for using the empirical laboratory data to extrapolate the performance of the actual grout disposal system to the long time periods of interest. 59 refs., 83 figs., 18 tabs

  8. Design, construction and performance of the Oldman River Dam grout curtain

    Energy Technology Data Exchange (ETDEWEB)

    Hartmaier, H.; Davachi, M. [Acres International Ltd., Calgary, AB (Canada); Dharmawardene, W. [Alberta Environment, Edmonton, AB (Canada); Sinclair, B. [Acres International Ltd., Niagara Falls, ON (Canada)

    2002-07-01

    The 76 m high Oldman River Dam was constructed between 1986 and 1991 near Pincher Creek, Alberta to provide flow regulation and on-stream storage of water for multi-purpose use and irrigation services as well as hydroelectric development. The dam's main structure includes an earth- and rockfill dam, a low earthfill dyke 1500 m long, twin diversion/low level outlet tunnels, a gated spillways structure, and 2 drainage tunnels. A 1.3 km long, three-line grout curtain up to 100 m deep extends below the foundation of the dam and spillway. The grout curtain was built in undeformed Paleocene sedimentary rocks affected by stress relief due to river valley erosion. 80 per cent of the grout consumption was from bedrock structural features. Piezometers, slope indicators and flow measurement weirs were installed in the dam and abutment areas both during and after construction to monitor the performance of the grout curtain. Instrument readings indicate that the grout curtain is successfully preventing the transmission of reservoir pressures to the foundation beneath the downstream shell of the dam. The piezometric pressures downstream of the grout curtain are the same as they were in the foundation before impounding. A small amount of seepage has appeared at the end of the grout curtain at the eastern end of the abutment of the spillway but it is not considered to be significant. 3 refs., 4 figs.

  9. Durability of low-pH injection grout. A literature survey

    International Nuclear Information System (INIS)

    Holt, E.

    2008-01-01

    This publication provides an overview of the durability of injection grouts. It is intended for use during planning and construction at the ONKALO underground research facility. The review has been done with respect to the application conditions, materials and service life requirements expressed by Posiva Oy. The publication describes all types of cement-based material durability, with an emphasis on the key issues of shrinkage cracking, leaching and sulphate attack. The second part of the report provides information on how durability expectations have changed with the history of injection grout development. The report gives information specific to low-pH injection grouts containing high amounts of silica fume performance and how their durability is expected to differ from traditional normal cement-based mixtures. The final part of the report provides suggestions for future research needs for ensuring the service life of injection grouts. The key finding from this study is that the low-pH grout material is not expected to have worse durability performance compared to the standard injection grout. Combining high amounts of silica fume with the cement to produce low-pH grout should result in a material having lower permeability and thus greater resistance to leaching and chemical attack. Further laboratory testing is needed to quantitatively verify these findings and to provide inputs for future service life modeling. (orig.)

  10. Hybrid life cycle assessment comparison of colloidal silica and cement grouted soil barrier remediation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, Patricia M., E-mail: pmg24@drexel.edu [Civil, Architectural and Environmental Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19038 (United States); Spatari, Sabrina; Cucura, Jeffrey [Civil, Architectural and Environmental Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19038 (United States)

    2013-04-15

    Highlights: ► We use LCA to study environmental impacts of grouting techniques for site remediation. ► We consider colloidal silica permeation grouting and cement jet grouting. ► Manufacturing and transportation contribute significantly in all impact categories. ► Activity outside of direct site activity is important in assessing impacts. ► LCA can be used to consider sustainability criteria for remediation decisions. -- Abstract: Site remediation involves balancing numerous costs and benefits but often neglects the environmental impacts over the entire project life cycle. Life cycle assessment (LCA) offers a framework for inclusion of global environmental “systems-level” decision metrics in combination with technological and cost analysis. We compare colloidal silica (CS) and cement grouted soil barrier remediation technologies for soils affected by low level radionuclides at a U.S. Superfund site using hybrid LCA methods. CS is a new, high performance grouting material installed using permeation grouting techniques. Cement, a more traditional grouting material, is typically installed using jet grouting techniques. Life cycle impacts were evaluated using the US EPA TRACI 2 model. Results show the highest life cycle environmental impacts for the CS barrier occur during materials production and transportation to the site. In general, the life cycle impacts for the cement barrier were dominated by materials production; however, in the extreme scenario the life cycle impacts were dominated by truck transportation of spoils to a distant, off-site radioactive waste facility. It is only in the extreme scenario tested in which soils are transported by truck (Option 2) that spoils waste transport dominates LCIA results. Life cycle environmental impacts for both grout barriers were most sensitive to resource input requirements for manufacturing volumes and transportation. Uncertainty associated with the efficacy of new technology such as CS over its required

  11. Hybrid life cycle assessment comparison of colloidal silica and cement grouted soil barrier remediation technologies

    International Nuclear Information System (INIS)

    Gallagher, Patricia M.; Spatari, Sabrina; Cucura, Jeffrey

    2013-01-01

    Highlights: ► We use LCA to study environmental impacts of grouting techniques for site remediation. ► We consider colloidal silica permeation grouting and cement jet grouting. ► Manufacturing and transportation contribute significantly in all impact categories. ► Activity outside of direct site activity is important in assessing impacts. ► LCA can be used to consider sustainability criteria for remediation decisions. -- Abstract: Site remediation involves balancing numerous costs and benefits but often neglects the environmental impacts over the entire project life cycle. Life cycle assessment (LCA) offers a framework for inclusion of global environmental “systems-level” decision metrics in combination with technological and cost analysis. We compare colloidal silica (CS) and cement grouted soil barrier remediation technologies for soils affected by low level radionuclides at a U.S. Superfund site using hybrid LCA methods. CS is a new, high performance grouting material installed using permeation grouting techniques. Cement, a more traditional grouting material, is typically installed using jet grouting techniques. Life cycle impacts were evaluated using the US EPA TRACI 2 model. Results show the highest life cycle environmental impacts for the CS barrier occur during materials production and transportation to the site. In general, the life cycle impacts for the cement barrier were dominated by materials production; however, in the extreme scenario the life cycle impacts were dominated by truck transportation of spoils to a distant, off-site radioactive waste facility. It is only in the extreme scenario tested in which soils are transported by truck (Option 2) that spoils waste transport dominates LCIA results. Life cycle environmental impacts for both grout barriers were most sensitive to resource input requirements for manufacturing volumes and transportation. Uncertainty associated with the efficacy of new technology such as CS over its required

  12. Approaches to control the quality of cementitious PFA grouts for nuclear waste encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Rice, G.; Miles, N.; Farris, S. [University of Nottingham, Nottingham (United Kingdom). Nottingham Mining & Minerals Centre

    2007-05-15

    Pulverised Fuel Ash (PFA) is combined with Ordinary Portland Cement (OPC) powder and water to form cementitious grouts for use in various aspects of nuclear waste encapsulation. Whilst specific PFA supplies in the United Kingdom currently deliver adequate grout performance it is also clear that some alternative supplies result in inferior performance, leading to concern over the long term availability of suitable raw material. This paper presents the results of an investigation into the characteristics of PFA that affect critical aspects of grout performance and identifies strategies that could be used to ensure high quality PFA supplies in the future.

  13. The effect of using different sources of dry materials on waste-form grout properties

    International Nuclear Information System (INIS)

    Spence, R.D.; Gilliam, T.M.; McDaniel, E.W.

    1992-01-01

    A reference grout formulation had been developed for a liquid low-level radioactive waste using the following dry materials: ground limestone, ground granulated blast furnace slag, fly ash, and cement. The effect of varying the sources of these dry materials are tested. Two limestones, two fly ashes, two cements, and eight slags were tested. Varying the source of dry materials significantly affected the grout properties, but only the 28-d free-standing liquid varied outside of the preferred range. A statistical technique, Tukey's paired comparison, can be used to ascertain whether a given combination of dry materials resulted in grout properties significantly different from those of other combinations of dry materials

  14. Grout formulation for disposal of low-level and hazardous waste streams containing fluoride

    Science.gov (United States)

    McDaniel, E.W.; Sams, T.L.; Tallent, O.K.

    1987-06-02

    A composition and related process for disposal of hazardous waste streams containing fluoride in cement-based materials is disclosed. the presence of fluoride in cement-based materials is disclosed. The presence of fluoride in waste materials acts as a set retarder and as a result, prevents cement-based grouts from setting. This problem is overcome by the present invention wherein calcium hydroxide is incorporated into the dry-solid portion of the grout mix. The calcium hydroxide renders the fluoride insoluble, allowing the grout to set up and immobilize all hazardous constituents of concern. 4 tabs.

  15. Discussion on the Influence of Various Technological Parameters on Jet Grouting Columns Geometry

    Directory of Open Access Journals (Sweden)

    Bzówka Joanna

    2015-06-01

    Full Text Available One of the most popular elements created by using jet grouting technology are columns. During designing such columns, it is a problem of estimating their shape and dimensions. The main factors that influence on columns geometry are soil characteristic and technological parameters. At the frame of Authors scientific research, following technological factors were taken into account: system of jet grouting, injection pressure, dimension of nozzles and rotation speed during injection. In the paper some results of the field tests of jet grouting columns are presented

  16. Effects of grouting, shotcreting and concrete leachates on backfill geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Luna, Miguel; Arcos, David; Duro, Lara [Enviros Consulting, Valldoreix, Barc elona (Spain)

    2007-11-15

    The use of concrete to seal open fractures (grouting) and to impermeabilise the deposition tunnels (shotcreting) has been envisaged in the construction of a high level nuclear waste (HLNW) repository according to SKB designs. Nevertheless, the geochemical effect of using concrete in the repository is not fully understood. Concrete degradation due to the interaction with groundwater can affect the performance of other repository barriers, such as the backfill material used for sealing the deposition tunnels. One of the main effects of concrete degradation is the generation of alkaline plumes. For this reason, SKB is currently planning to use a type of concrete whose degradation result in lower pH values than those developed with Ordinary Portland Cement (OPC). In order to assess the long-term geochemical effect of including low-pH concrete elements in a HLNW repository, we performed a 2D reactive-transport model of a backfilled deposition tunnel that intersects a hydraulic conductive fracture which has been partially grouted. An additional case has been modelled where part of the deposition tunnel walls were covered with a shotcrete layer. The modelling results predict the development of a high-alkalinity plume, larger in the case of considering a grouted fracture, accompanied by the precipitation of CSH-phases in the fracture. However, the effect on the backfill material is only significant if concrete is in contact with the backfill (shotcrete case). In order to conduct these models, and considering that at the beginning of the present work there was not a specific composition for such a low-pH concrete, its composition has been assumed in order to meet the expected geochemical evolution of concrete degradation according to SKB expectations. This is a pH of pore water of around 11 and the degradation of CSH phases resulting in a source for Ca and Si into the system. For this reason, jennite and tobermorite have been selected, although it is known that jennite is

  17. Effects of grouting, shotcreting and concrete leachates on backfill geochemistry

    International Nuclear Information System (INIS)

    Luna, Miguel; Arcos, David; Duro, Lara

    2007-11-01

    The use of concrete to seal open fractures (grouting) and to impermeabilise the deposition tunnels (shotcreting) has been envisaged in the construction of a high level nuclear waste (HLNW) repository according to SKB designs. Nevertheless, the geochemical effect of using concrete in the repository is not fully understood. Concrete degradation due to the interaction with groundwater can affect the performance of other repository barriers, such as the backfill material used for sealing the deposition tunnels. One of the main effects of concrete degradation is the generation of alkaline plumes. For this reason, SKB is currently planning to use a type of concrete whose degradation result in lower pH values than those developed with Ordinary Portland Cement (OPC). In order to assess the long-term geochemical effect of including low-pH concrete elements in a HLNW repository, we performed a 2D reactive-transport model of a backfilled deposition tunnel that intersects a hydraulic conductive fracture which has been partially grouted. An additional case has been modelled where part of the deposition tunnel walls were covered with a shotcrete layer. The modelling results predict the development of a high-alkalinity plume, larger in the case of considering a grouted fracture, accompanied by the precipitation of CSH-phases in the fracture. However, the effect on the backfill material is only significant if concrete is in contact with the backfill (shotcrete case). In order to conduct these models, and considering that at the beginning of the present work there was not a specific composition for such a low-pH concrete, its composition has been assumed in order to meet the expected geochemical evolution of concrete degradation according to SKB expectations. This is a pH of pore water of around 11 and the degradation of CSH phases resulting in a source for Ca and Si into the system. For this reason, jennite and tobermorite have been selected, although it is known that jennite is

  18. In situ measurement of the effect of LiOH on the stability of zircaloy-2 surface film in PWR water

    International Nuclear Information System (INIS)

    Saario, T.; Taehtinen, S.

    1997-01-01

    Surface films on the metals play a major role in corrosion assisted cracking. A new method called Contact Electric Resistance (CER) method has been recently developed for in situ measurement of the electric resistance of surface films in high temperature and high pressure environments. The technique has been used to determine in situ the electric resistance of films on metals when in contact with water and dissolved anions, during formation and destruction of oxides and hydrides and during electroplating of metals. Electric resistance data can be measured with a frequency of the order of one hertz, which makes it possible to investigate in situ the kinetics of surface film related processes which are dependent on the environment, temperature, pH and electrochemical potential. This paper presents the results of the CER investigation on the effects of LiOH on the stability of Zircaloy-2 surface film in water with 2000 ppm H 3 BO 3 . At 300 deg. C the LiOH concentrations higher than 10 -2 M (roughly 70 ppm of Li + ) were found to markedly reduce the electric resistance of the Zircaloy-2 surface film during a test period of less than two hours. The decrease of the film resistance is very abrupt, possibly indicating a phase transformation. Moreover, the advantages of the CER technique over the other competing techniques which rely on the measurement of current are discussed. (author)

  19. In situ measurement of the effect of LiOH on the stability of zircaloy-2 surface film in PWR water

    Energy Technology Data Exchange (ETDEWEB)

    Saario, T; Taehtinen, S [Technical Research Centre of Finland, Espoo (Finland)

    1997-02-01

    Surface films on the metals play a major role in corrosion assisted cracking. A new method called Contact Electric Resistance (CER) method has been recently developed for in situ measurement of the electric resistance of surface films in high temperature and high pressure environments. The technique has been used to determine in situ the electric resistance of films on metals when in contact with water and dissolved anions, during formation and destruction of oxides and hydrides and during electroplating of metals. Electric resistance data can be measured with a frequency of the order of one hertz, which makes it possible to investigate in situ the kinetics of surface film related processes which are dependent on the environment, temperature, pH and electrochemical potential. This paper presents the results of the CER investigation on the effects of LiOH on the stability of Zircaloy-2 surface film in water with 2000 ppm H{sub 3}BO{sub 3}. At 300 deg. C the LiOH concentrations higher than 10{sup -2} M (roughly 70 ppm of Li{sup +}) were found to markedly reduce the electric resistance of the Zircaloy-2 surface film during a test period of less than two hours. The decrease of the film resistance is very abrupt, possibly indicating a phase transformation. Moreover, the advantages of the CER technique over the other competing techniques which rely on the measurement of current are discussed. (author).

  20. Combining in situ chemical oxidation, stabilization, and anaerobic bioremediation in a single application to reduce contaminant mass and leachability in soil

    Energy Technology Data Exchange (ETDEWEB)

    Cassidy, Daniel P., E-mail: daniel.cassidy@wmich.edu [Department of Geosciences, Western Michigan University, Kalamazoo, MI 49008 (United States); Srivastava, Vipul J., E-mail: vipul.srivastava@ch2m.com [CH2M HILL, 125S Wacker, Ste 3000, Chicago, IL 60606 (United States); Dombrowski, Frank J., E-mail: frank.dombrowski@we-energies.com [We Energies, 333W Everett St., A231, Milwaukee, WI 53203 (United States); Lingle, James W., E-mail: jlingle@epri.com [Electric Power Research Institute (EPRI), 4927W Willow Road, Brown Deer, WI 53223 (United States)

    2015-10-30

    Highlights: • Portland cement and lime activated persulfate by increasing pH and temperature. • Chemical oxidation achieved BTEX and PAH removal ranging from 55% to 75%. • Activating persulfate with ISS amendments reduced leachability more than NaOH. • Native sulfate-reducing bacteria degraded PAHs within weeks after ISCO finished. • ISCO, ISS, and anaerobic bioremediation were combined in a single application. - Abstract: Laboratory batch reactors were maintained for 32 weeks to test the potential for an in situ remedy that combines chemical oxidation, stabilization, and anaerobic bioremediation in a single application to treat soil from a manufactured gas plant, contaminated with polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Portland cement and slaked lime were used to activate the persulfate and to stabilize/encapsulate the contaminants that were not chemically oxidized. Native sulfate-reducing bacteria degraded residual contaminants using the sulfate left after persulfate activation. The ability of the combined remedy to reduce contaminant mass and leachability was compared with NaOH-activated persulfate, stabilization, and sulfate-reducing bioremediation as stand-alone technologies. The stabilization amendments increased pH and temperature sufficiently to activate the persulfate within 1 week. Activation with both stabilization amendments and NaOH removed between 55% and 70% of PAH and BTEX. However, combined persulfate and stabilization significantly reduced the leachability of residual BTEX and PAH compared with NaOH activation. Sulfide, 2-naphthoic acid, and the abundance of subunit A of the dissimilatory sulfite reductase gene (dsrA) were used to monitor native sulfate-reducing bacteria, which were negatively impacted by activated persulfate, but recovered completely within weeks.

  1. Combining in situ chemical oxidation, stabilization, and anaerobic bioremediation in a single application to reduce contaminant mass and leachability in soil

    International Nuclear Information System (INIS)

    Cassidy, Daniel P.; Srivastava, Vipul J.; Dombrowski, Frank J.; Lingle, James W.

    2015-01-01

    Highlights: • Portland cement and lime activated persulfate by increasing pH and temperature. • Chemical oxidation achieved BTEX and PAH removal ranging from 55% to 75%. • Activating persulfate with ISS amendments reduced leachability more than NaOH. • Native sulfate-reducing bacteria degraded PAHs within weeks after ISCO finished. • ISCO, ISS, and anaerobic bioremediation were combined in a single application. - Abstract: Laboratory batch reactors were maintained for 32 weeks to test the potential for an in situ remedy that combines chemical oxidation, stabilization, and anaerobic bioremediation in a single application to treat soil from a manufactured gas plant, contaminated with polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Portland cement and slaked lime were used to activate the persulfate and to stabilize/encapsulate the contaminants that were not chemically oxidized. Native sulfate-reducing bacteria degraded residual contaminants using the sulfate left after persulfate activation. The ability of the combined remedy to reduce contaminant mass and leachability was compared with NaOH-activated persulfate, stabilization, and sulfate-reducing bioremediation as stand-alone technologies. The stabilization amendments increased pH and temperature sufficiently to activate the persulfate within 1 week. Activation with both stabilization amendments and NaOH removed between 55% and 70% of PAH and BTEX. However, combined persulfate and stabilization significantly reduced the leachability of residual BTEX and PAH compared with NaOH activation. Sulfide, 2-naphthoic acid, and the abundance of subunit A of the dissimilatory sulfite reductase gene (dsrA) were used to monitor native sulfate-reducing bacteria, which were negatively impacted by activated persulfate, but recovered completely within weeks

  2. Concept study: Use of grout vaults for disposal of long-length contaminated equipment

    International Nuclear Information System (INIS)

    Clem, D.K.

    1994-01-01

    Study considers the potential for use of grout vaults for disposal of untreated long length equipment removed from waste tanks. Looks at ways to access vaults, material handling, regulatory aspects, and advantages and disadvantages of vault disposal

  3. Corrosion performance of prestressing strands in contact with dissimilar grouts : technical summary.

    Science.gov (United States)

    2013-01-01

    Inspections of post-tensioned bridges : by the Kansas Department of Transportation : have revealed voids in strand ducts due to : bleeding and shrinkage of older Portland : Cement grouts. The Kansas Department : of Transportation is faced with a deci...

  4. Grouting techniques for the unfavorable geological conditions of Xiang'an subsea tunnel in China

    Directory of Open Access Journals (Sweden)

    Dingli Zhang

    2014-10-01

    Full Text Available One of the major challenges during subsea tunnel construction is to seal the potential water inflow. The paper presents a case study of Xiang'an subsea tunnel in Xiamen, the first subsea tunnel in China. During its construction, different grades of weathered geomaterials were encountered, which was the challenging issue for this project. To deal with these unfavorable geological conditions, grouting was adopted as an important measure for ground treatment. The grouting mechanism is first illustrated by introducing a typical grouting process. Then the site-specific grouting techniques employed in the Xiang'an subsea tunnel are elaborated. By using this ground reinforcement technique, the tunneling safety of the Xiang'an subsea tunnel was guaranteed.

  5. Growth of block copolymer stabilized metal nanoparticles probed simultaneously by in situ XAS and UV-Vis spectroscopy.

    Science.gov (United States)

    Nayak, C; Bhattacharyya, D; Jha, S N; Sahoo, N K

    2016-01-01

    The growth of Au and Pt nanoparticles from their respective chloride precursors using block copolymer-based reducers has been studied by simultaneous in situ measurement of XAS and UV-Vis spectroscopy at the energy-dispersive EXAFS beamline (BL-08) at INDUS-2 SRS at RRCAT, Indore, India. While the XANES spectra of the precursor give real-time information on the reduction process, the EXAFS spectra reveal the structure of the clusters formed at the intermediate stages of growth. The growth kinetics of both types of nanoparticles are found to be almost similar and are found to follow three stages, though the first stage of nucleation takes place earlier in the case of Au than in the case of Pt nanoparticles due to the difference in the reduction potential of the respective precursors. The first two stages of the growth of Au and Pt nanoparticles as obtained by in situ XAS measurements could be corroborated by simultaneous in situ measurement of UV-Vis spectroscopy also.

  6. Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

    Science.gov (United States)

    Zhao, Tong; Liu, Changyou

    2017-12-01

    Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

  7. Field lysimeter studies for performance evaluation of grouted Hanford defense wastes

    International Nuclear Information System (INIS)

    Last, G.V.; Serne, R.J.; LeGore, V.L.

    1995-02-01

    The Grout Waste Test Facility (GWTF) consisted of four large field lysimeters designed to test the leaching and migration rates of grout-solidified low-level radioactive wastes generated by Hanford Site operations. Each lysimeter was an 8-m-deep by 2-media closed-bottom caisson that was placed in the ground such that the uppermost rim remained just above grade. Two of these lysimeters were used; the other two remained empty. The two lysimeters that were used (A-1 and B-1) were backfilled with a two-layer soil profile representative of the proposed grout disposal site. The proposed grout disposal site (termed the Grout Treatment Facility Landfill) is located immediately east of the Hanford Site's 200 East Area. This soil profile consisted of a coarse sand into which the grout waste forms were placed and covered by 4 m of a very fine sand. The A-1 lysimeter was backfilled in March 1985, with a grout-solidified phosphate/sulfate liquid waste from N Reactor decontamination and ion exchange resin regeneration. The B-1 lysimeter was backfilled in September 1985 and received a grout-solidified simulated cladding removal waste representative of waste generated from fuel reprocessing operations at the head end of the Plutonium Uranium Extraction (PUREX) plant. Routine monitoring and leachate collection activities were conducted for over three years, terminating in January 1989. Drainage was collected sporadically between January 1989 and December 1992. Decontamination and decommissioning of these lysimeters during the summer of 1994, confirmed the presence of a 15 to 20-cm-long hairline crack in one of the bottom plate welds. This report discusses the design and construction of the GWTF, presents the routine data collected from this facility through January 1989 and subsequent data collected sporadically between 1989 and 1993, and provides a brief discussion concerning preliminary interpretation of the results

  8. The grouting handbook a step-by-step guide for foundation design and machinery installation

    CERN Document Server

    Harrison, Donald M

    2013-01-01

    Minimize loss of revenue and the downtime of critical assets by avoiding foundation cracking, poor bonds, and initial alignment changes. After their successful introduction as a maintenance material, machinery grouts are now being used for equipment placement in new construction. While certainly suitable for both markets and applications, a successful installation depends on proper grout selection, application, foundation preparation, and forming methods. Therefore, guidelines on their uses and limitations are needed for engineers and maintenance personnel. Based on 45 years of field experi

  9. Characterisation of vibration equipment used for the immobilisation of solid items in cement grout

    International Nuclear Information System (INIS)

    Dalton, M.J.

    1984-12-01

    Processes are being developed at AEE Winfrith for the immobilisation of solid radioactive waste in cement grouts. The flow of grout during the infilling stage is assisted by vibration of the waste container. A high resolution signal analyser has been used to measure the operating frequency and amplitude characteristics of vibrating equipment used in the solid immobilisation process. In this report the commissioning of the instrument and results obtained on the equipment are described. (author)

  10. Development of Freshwater Grout Subsequent to the Bell Canyon Tests (BCT).

    Science.gov (United States)

    1986-04-01

    specimens of those grouts cured and studied in the SL, to three-years age. Selected data from earlier tests of related fresh-water grouts are...specimens were either coated with a strippable plastic momn;rane, or sealed in plastic cylinders with tightly fitting lids. Sealed in plastiC habs in...for expansion prisms, the strippable coating applied to SPDV specimens did not prevent water loss. Lower strength gain may be attributable to partial

  11. A systematic review of biochar research, with a focus on its stability in situ and its promise as a climate mitigation strategy.

    Directory of Open Access Journals (Sweden)

    Noel P Gurwick

    Full Text Available BACKGROUND: Claims about the environmental benefits of charring biomass and applying the resulting "biochar" to soil are impressive. If true, they could influence land management worldwide. Alleged benefits include increased crop yields, soil fertility, and water-holding capacity; the most widely discussed idea is that applying biochar to soil will mitigate climate change. This claim rests on the assumption that biochar persists for hundreds or thousands of years, thus storing carbon that would otherwise decompose. We conducted a systematic review to quantify research effort directed toward ten aspects of biochar and closely evaluated the literature concerning biochar's stability. FINDINGS: We identified 311 peer-reviewed research articles published through 2011. We found very few field studies that addressed biochar's influence on several ecosystem processes: one on soil nutrient loss, one on soil contaminants, six concerning non-CO2 greenhouse gas (GHG fluxes (some of which fail to support claims that biochar decreases non-CO2 GHG fluxes, and 16-19 on plants and soil properties. Of 74 studies related to biochar stability, transport or fate in soil, only seven estimated biochar decomposition rates in situ, with mean residence times ranging from 8 to almost 4,000 years. CONCLUSIONS: Our review shows there are not enough data to draw conclusions about how biochar production and application affect whole-system GHG budgets. Wide-ranging estimates of a key variable, biochar stability in situ, likely result from diverse environmental conditions, feedstocks, and study designs. There are even fewer data about the extent to which biochar stimulates decomposition of soil organic matter or affects non-CO2 GHG emissions. Identifying conditions where biochar amendments yield favorable GHG budgets requires a systematic field research program. Finally, evaluating biochar's suitability as a climate mitigation strategy requires comparing its effects with

  12. Stabilization

    Directory of Open Access Journals (Sweden)

    Muhammad H. Al-Malack

    2016-07-01

    Full Text Available Fuel oil flyash (FFA produced in power and water desalination plants firing crude oils in the Kingdom of Saudi Arabia is being disposed in landfills, which increases the burden on the environment, therefore, FFA utilization must be encouraged. In the current research, the effect of adding FFA on the engineering properties of two indigenous soils, namely sand and marl, was investigated. FFA was added at concentrations of 5%, 10% and 15% to both soils with and without the addition of Portland cement. Mixtures of the stabilized soils were thoroughly evaluated using compaction, California Bearing Ratio (CBR, unconfined compressive strength (USC and durability tests. Results of these tests indicated that stabilized sand mixtures could not attain the ACI strength requirements. However, marl was found to satisfy the ACI strength requirement when only 5% of FFA was added together with 5% of cement. When the FFA was increased to 10% and 15%, the mixture’s strength was found to decrease to values below the ACI requirements. Results of the Toxicity Characteristics Leaching Procedure (TCLP, which was performed on samples that passed the ACI requirements, indicated that FFA must be cautiously used in soil stabilization.

  13. Grout compactness monitoring of concrete-filled fiber-reinforced polymer tube using electromechanical impedance

    Science.gov (United States)

    Shi, Yaokun; Luo, Mingzhang; Li, Weijie; Song, Gangbing

    2018-05-01

    The concrete-filled fiber-reinforced polymer tube (CFFT) is a type of structural element widely used in corrosive environments. Poor grout compactness results in incomplete contact or even no contact between the fiber-reinforced polymer (FRP) tube and the concrete grout, which reduces the load bearing capacity of a CFFT. The monitoring of grout compactness for CFFTs is important. The piezoceramic-based electromechanical impedance (EMI) method has emerged as an efficient and low-cost structural health monitoring technique. This paper presents a feasibility study using the EMI method to monitor grout compactness of CFFTs. In this research, CFFT specimens with different levels of compactness (empty, 1/5, 1/3, 1/2, 2/3, and full compactness) were prepared and subjected to EMI measurement by using four piezoceramic patches that were bonded circumferentially along the outer surface of the CFFT. To analyze the correlation between grout compactness and EMI signatures, a compactness index (CI) was proposed based on the root-mean-square deviation (RMSD). The experimental results show that the changes in admittance signatures are able to determine the grout compactness qualitatively. The proposed CI is able to effectively identify the compactness of the CFFT, and provides location information of the incomplete concrete infill.

  14. Use of jet grouting to create a low permeability horizontal barrier below an incinerator ash landfill

    International Nuclear Information System (INIS)

    Furth, A.J.; Burke, G.K.; Deutsch, W.L. Jr.

    1997-01-01

    The City of Philadelphia's Division of Aviation (DOA) has begun construction of a new commuter runway, designated as Runway 8-26, at the Philadelphia International Airport. A portion of this runway will be constructed over a former Superfund site known as the Enterprise Avenue Landfill, which for many years was used to dispose of solid waste incinerator ash and other hazardous materials. The site was clay capped in the 1980's, but in order for the DOA to use the site, additional remediation was needed to meet US EPA final closure requirements. One component of the closure plan included installation of a low permeability horizontal barrier above a very thin (approximately 0.61 to 0.91 meters) natural clay stratum which underlies an approximately 1020 m 2 area of the landfill footprint so as to insure that a minimum 1.52 meter thick low permeability barrier exists beneath the entire 150,000 m 2 landfill. The new barrier was constructed using jet grouting techniques to achieve remote excavation and replacement of the bottom 0.91 meters of the waste mass with a low permeability grout. The grout was formulated to meet the low permeability, low elastic modulus and compressive strength requirements of the project design. This paper will discuss the advantages of using jet grouting for the work and details the development of the grout mixture, modeling of the grout zone under load, field construction techniques, performance monitoring and verification testing

  15. Strength Assessment of Broken Rock Postgrouting Reinforcement Based on Initial Broken Rock Quality and Grouting Quality

    Directory of Open Access Journals (Sweden)

    Hongfa Xu

    2017-01-01

    Full Text Available To estimate postgrouting rock mass strength growth is important for engineering design. In this paper, using self-developed indoor pressure-grouting devices, 19 groups of test cubic blocks were made of the different water cement ratio grouting into the broken rock of three kinds of particle sizes. The shear strength parameters of each group under different conditions were tested. Then this paper presents a quantitative calculation method for predicting the strength growth of grouted broken rock. Relational equations were developed to investigate the relationship between the growth rates of uniaxial compressive strength (UCS, absolute value of uniaxial tensile strength (AUTS, internal friction angle, and cohesion for post- to pregrouting broken rock based on Mohr-Coulomb strength criterion. From previous test data, the empirical equation between the growth rate of UCS and the ratio of the initial rock mass UCS to the grout concretion UCS has been determined. The equations of the growth rates of the internal friction coefficient and UCS for grouting broken rock with rock mass rating (RMR and its increment have been established. The calculated results are consistent with the experimental results. These observations are important for engineered design of grouting reinforcement for broken rock mass.

  16. Structural model testing for prestressed concrete pressure vessels: a study of grouted vs nongrouted posttensioned prestressing tendon systems

    International Nuclear Information System (INIS)

    Naus, D.J.

    1979-04-01

    Nongrouted tendons are predominantly used in this country as the prestressing system for prestressed concrete pressure vessels (PCPVs) because they are more easily surveyed to detect reductions in prestressing level and distress such as results from corrosion. Grouted tendon systems, however, offer advantages which may make them cost-effective for PCPV applications. Literature was reviewed to (1) provide insight on the behavior of grouted tendon system, (2) establish performance histories for structures utilizing grouted tendons, (3) examine corrosion protection procedures for prestressing tendons, (4) identify arguments for and against using grouted tendons, and (5) aid in the development of the experimental investigation. The experimental investigation was divided into four phases: (1) grouted-nongrouted tendon behavior, (2) evaluation of selected new material systems, (3) bench-scale corrosion studies, and (4) preliminary evaluation of acoustic emission techniques for monitoring grouted tendons in PCPVs. The groutability of large tendon systems was also investigated

  17. Predicting the stability of horizontal wells and multi-laterals - the role of in situ stress and rock properties

    Energy Technology Data Exchange (ETDEWEB)

    Moos, A.; Peska, P. [GeoMechanics International (United States); Zoback, M. D. [Stanford Univ., CA (United States)

    1998-12-31

    A new suite of software tools, developed to study wellbore stability in a wide variety of geologic environments is introduced as means by which to accurately predict optimally-stable wellbore trajectories from knowledge of the stress tensor. In step one of the process stress, is determined from observations of failure in existing wells; in step two, this knowledge is applied to predict the stability of proposed wells while drilling, as well as later during production. Three case studies are presented to illustrate use of this approach. The examples concentrate on issues related to the stability of highly inclined wells, but the approach can be used to determine the state of stress for other purposes as well. 21 refs., 8 figs.

  18. Biodegradable surfactant stabilized nanoscale zero-valent iron for in situ treatment of vinyl chloride and 1,2-dichloroethane

    International Nuclear Information System (INIS)

    Wei, Yu-Ting; Wu, Shian-chee; Yang, Shi-Wei; Che, Choi-Hong; Lien, Hsing-Lung; Huang, De-Huang

    2012-01-01

    Highlights: ► Biodegradable surfactant stabilized nanoscale zero-valent iron (NZVI) is tested. ► Vinyl chloride and 1,2-dichloroethane are remediated by NZVI in the field. ► Multiple functions of biodegradable surfactants are confirmed. ► Biodegradable surfactants stabilize NZVI and facilitate the bioremediation. ► NZVI creates reducing conditions beneficial to an anaerobic bioremediation. - Abstract: Nanoscale zero-valent iron (NZVI) stabilized with dispersants is a promising technology for the remediation of contaminated groundwater. In this study, we demonstrated the use of biodegradable surfactant stabilized NZVI slurry for successful treatment of vinyl chloride (VC) and 1,2-dichloroethane (1,2-DCA) in a contaminated site in Taiwan. The biodegradable surfactant stabilized NZVI was coated with palladium and synthesized on-site. From monitoring the iron concentration breakthrough and distribution, it was found that the stabilized NZVI is capable of transporting in the aquifer at the test plot (200 m 2 ). VC was effectively degraded by NZVI while the 1,2-DCA degradation was relatively sluggish during the 3-month field test. Nevertheless, as 1,2-DCA is known to resist abiotic reduction by NZVI, the observation of 1,2-DCA degradation and hydrocarbon production suggested a bioremediation took place. ORP and pH results revealed that a reducing condition was achieved at the testing area facilitating the biodegradation of chlorinated organic hydrocarbons. The bioremediation may be attributed to the production of hydrogen gas as electron donor from the corrosion of NZVI in the presence of water or the added biodegradable surfactant serving as the carbon source as well as electron donor to stimulate microbial growth.

  19. Test Technical of Bottom Grouting Effect Above High Confined Water Mining%隧道工程富水破碎带注浆加固效果综合评定技术

    Institute of Scientific and Technical Information of China (English)

    姬程飞; 孙小菊; 刘涛

    2017-01-01

    注浆技术已成为地下工程中重要的辅助工法,它对于破碎带加固、断层注浆堵水、沉降控制等工程有着极好效果,而注浆效果检验评定技术对于注浆效果质量的优劣具有重要意义.以山西某隧道为试验隧道,采用物探法、开挖取样法、渗透系数测试法、数字钻孔电视法对隧道工程注浆效果进行评定.研究结果表明:注浆后黑色条纹已经变淡或者消失,注浆材料已充填破碎围岩,注浆后隧道岩层整体性得到提高;注浆后地层的渗透系数为1.57×10-5~1.64×10-5cm/s之间;注浆后裂隙数量减少20条且裂隙宽度明显降低;隧道开挖过程中围岩稳定且无漏水现象,实现了安全开挖.%Grouting technology is an important auxiliary method to underground engineering for it has a good effect on reinforcement of fracture zone,water blockage,subsidence control,etc..but,technology of grouting effect test is very significance for pros and cons of quality of grouting effect.taking Shanxi a certain tunnel as the experimental tunnel,by using physical exploration method、method of inspection hole、test method of permeability coefficient,grouting effect of floor undulation is evaluated,At the same time,Characteristic of tunnel excavation is monitored.The results show that: ① The black fringe image has paled or disappeared,Grouting material has been filled with crushed surrounding rock,the integrity of floor strata is improved;② Permeability coefficient of strata is 1.58×10-5~1.64×10-5cm/s after grouting;③ Quantity of fractures is reduced 35 and width of fractures is obvious decreased after grouting;④ During excavation tunnel surrounding rock without leaks,and rock stability,to achieve objective of safety mining.

  20. Low-pH injection grout for deep repositories. Summary report from a co-operation project between NUMO (Japan), Posiva (Finland) and SKB (Sweden)

    International Nuclear Information System (INIS)

    Boden, Anders; Sievaenen, Ursula

    2005-06-01

    experiments. 5. Fly ash system was ruled out at an early stage due to expected problems concerning the availability and stability of the raw material properties as well as expected difficulties with the setting time of the mixes. The grouting related properties tested in laboratory were penetrability, bleeding, early age shear strength viscosity and yield value. For some selected mixes fluidity was also measured. The key uncertainties identified with respect to the use of cement in a repository are related to the uncertainties in the estimation of the range and effect of the pH-plume on the rock, as well as the possible detrimental effects on bentonite due to cement/bentonite interaction. In the present study the potential effects on the repository performance and the rock have been evaluated based on the composition of the materials and leaching tests, expert judgement and some simple mass balance and diffusion calculations. A first review of the potential effects of organic cement additives on the radionuclide mobility has also been done, although the preference at the outset of the project was to develop an injection grout without organic additives. Also the long-term durability of the low-pH cementitious material and the long-term phase changes/degradation and leaching of the grout is not yet known and need to be evaluated. The non-cementitious candidate materials were investigated regarding basic properties and long-term safety aspects in order to form the basis for the decision whether silica sol can be used in the deep repository and whether periclase (MgO) should be further investigated. In a small field-test it was also investigated if the penetration of silica sol can be predicted based on hydraulic tests, transmissivity and hydraulic aperture. Silica sol, colloidal silica, is a stable dispersion of discrete non porous particles of amorphous silicon dioxide. Rock grouting with silica sol is a relatively new application. Colloidal silica seems to be a feasible

  1. Low-pH injection grout for deep repositories. Summary report from a co-operation project between NUMO (Japan), Posiva (Finland) and SKB (Sweden)

    Energy Technology Data Exchange (ETDEWEB)

    Boden, Anders [SwedPower AB, Stockholm (Sweden); Sievaenen, Ursula [JP-Suoraplan Oy, Vantaa (Finland)

    2005-06-01

    fineness, were modified in the present experiments. 5. Fly ash system was ruled out at an early stage due to expected problems concerning the availability and stability of the raw material properties as well as expected difficulties with the setting time of the mixes. The grouting related properties tested in laboratory were penetrability, bleeding, early age shear strength viscosity and yield value. For some selected mixes fluidity was also measured. The key uncertainties identified with respect to the use of cement in a repository are related to the uncertainties in the estimation of the range and effect of the pH-plume on the rock, as well as the possible detrimental effects on bentonite due to cement/bentonite interaction. In the present study the potential effects on the repository performance and the rock have been evaluated based on the composition of the materials and leaching tests, expert judgement and some simple mass balance and diffusion calculations. A first review of the potential effects of organic cement additives on the radionuclide mobility has also been done, although the preference at the outset of the project was to develop an injection grout without organic additives. Also the long-term durability of the low-pH cementitious material and the long-term phase changes/degradation and leaching of the grout is not yet known and need to be evaluated. The non-cementitious candidate materials were investigated regarding basic properties and long-term safety aspects in order to form the basis for the decision whether silica sol can be used in the deep repository and whether periclase (MgO) should be further investigated. In a small field-test it was also investigated if the penetration of silica sol can be predicted based on hydraulic tests, transmissivity and hydraulic aperture. Silica sol, colloidal silica, is a stable dispersion of discrete non porous particles of amorphous silicon dioxide. Rock grouting with silica sol is a relatively new application

  2. Study of evaluation for grouting effect in a borehole; Yakueki chunyu koka hyoka gijutsu ni okeru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, H; Matsuo, T [Fukuoka Municipal Transportation Bureau, Fukuoka (Japan); Yamauchi, Y; Imanishi, H [Osaka Soil Test, Osaka (Japan)

    1996-10-01

    For the foundation improvement works by grouting in a borehole, evaluation of grouting effect is one of the most important management items. The grouting design and works are sometimes reconsidered depending on the evaluation of grouting effect during the test injection. The purpose of the evaluation of grouting effect is to grasp the range of improvement and consolidation after the injection, and to judge and estimate the strength and permeability of the consolidation part. This paper describes the judgment method of the strength using PS logging results and borehole televiewer (BHTV) logging results. The reflection intensity (Ir) by the BHTV logging increased after the grouting, which showed a same tendency as that using S-wave and P-wave velocities (Vs and Vp) before and after the grouting. This was considered to demonstrate the grouting effect. A relation was obtained between the Vs, Vp and Ir before and after the grouting, which was expressed by following equation. Ir=0.143{times}Vs-70=0.093{times}Vp-110. The relation with the dynamic elastic coefficient (Ed) was also obtained as follow; Ir=0.0013{times}Ed. 9 figs.

  3. Microstructure evolution, thermal stability and fractal behavior of water vapor flow assisted in situ growth poly(vinylcarbazole)-titania quantum dots nanocomposites

    Science.gov (United States)

    Mombrú, Dominique; Romero, Mariano; Faccio, Ricardo; Mombrú, Alvaro W.

    2017-12-01

    Here, we report a novel strategy for the preparation of TiO2 quantum dots fillers prepared from alkoxide precursor via in situ water vapor flow diffusion into poly(N-vinylcarbazole) host. A detailed characterization by means of infrared and Raman spectroscopy, X-ray powder diffraction, small angle X-ray scattering and differential scanning calorimetry is reported. The growth mechanism of both crystallites and particles was mostly governed by the classical coarsening reaction limited growth and the polymer host showed no detectable chemical modifications at the interface or active participation in the growing process. The main relevance of our strategy respect to the typical sol-gel growth in solution is the possibility of the interruption of the reaction by simple stopping the water vapor flow diffusion into the polymer host thus achieving good control in the nanoparticles size. The thermal stability and fractal behavior of our nanocomposites were also studied by differential scanning calorimetry and in situ small angle X-ray scattering versus temperature. Strong correlations between modifications in the fractal behavior and glass transition or fusion processes were observed for these nanocomposites.

  4. In Situ Studies of Fe4+ Stability in β-Li3Fe2(PO4)3 Cathodes for Li Ion Batteries

    DEFF Research Database (Denmark)

    Christiansen, Ane Sælland; Johnsen, Rune E.; Norby, Poul

    2015-01-01

    In commercial Fe-based batteries the Fe2+/Fe3+ oxidation states are used, however by also utilizing the Fe4+ oxidation state, intercalation of up to two Li ions per Fe ion could be possible. In this study, we investigate whether Fe4+ can be formed and stabilized in β-Li3Fe2(PO4)3. The work includes...... of Fe4+ formation. Oxidation of the organic electrolyte is inevitable at 4.5 V but this alone cannot explain the volume change. Instead, a reversible oxygen redox process (O2− → O−) could possibly explain and charge compensate for the reversible extraction of lithium ions from β-Li3Fe2(PO4)3....... in situ synchrotron X-ray powder diffraction studies (XRPD) during charging of β-Li3Fe2(PO4)3 up to 5.0 V vs. Li/Li+. A novel capillary-based micro battery cell for in situ XRPD has been designed for this. During charge, a plateau at 4.5 V was found and a small contraction in volume was observed...

  5. Understanding the Thermal Stability of Palladium-Platinum Core-Shell Nanocrystals by In Situ Transmission Electron Microscopy and Density Functional Theory.

    Science.gov (United States)

    Vara, Madeline; Roling, Luke T; Wang, Xue; Elnabawy, Ahmed O; Hood, Zachary D; Chi, Miaofang; Mavrikakis, Manos; Xia, Younan

    2017-05-23

    Core-shell nanocrystals offer many advantages for heterogeneous catalysis, including precise control over both the surface structure and composition, as well as reduction in loading for rare and costly metals. Although many catalytic processes are operated at elevated temperatures, the adverse impacts of heating on the shape and structure of core-shell nanocrystals are yet to be understood. In this work, we used ex situ heating experiments to demonstrate that Pd@Pt 4L core-shell nanoscale cubes and octahedra are promising for catalytic applications at temperatures up to 400 °C. We also used in situ transmission electron microscopy to monitor the thermal stability of the core-shell nanocrystals in real time. Our results demonstrate a facet dependence for the thermal stability in terms of shape and composition. Specifically, the cubes enclosed by {100} facets readily deform shape at a temperature 300 °C lower than that of the octahedral counterparts enclosed by {111} facets. A reversed trend is observed for composition, as alloying between the Pd core and the Pt shell of an octahedron occurs at a temperature 200 °C lower than that for the cubic counterpart. Density functional theory calculations provide atomic-level explanations for the experimentally observed behaviors, demonstrating that the barriers for edge reconstruction determine the relative ease of shape deformation for cubes compared to octahedra. The opposite trend for alloying of the core-shell structure can be attributed to a higher propensity for subsurface Pt vacancy formation in octahedra than in cubes.

  6. Reactive transport modeling of the interaction between water and a cementitious grout in a fractured rock. Application to ONKALO (Finland)

    Energy Technology Data Exchange (ETDEWEB)

    Soler, Josep M., E-mail: josep.soler@idaea.csic.es [IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona (Spain); Vuorio, Marja; Hautojaervi, Aimo [POSIVA OY, Olkiluoto, FI-27160 Eurajoki (Finland)

    2011-07-15

    Highlights: > It is planned to seal conductive fractures near a repository with cementitious grout. > Modeling includes simultaneous hydration and leaching of the grout. > Modeling results show a very limited formation of the high-pH plume. > Results are in qualitative agreement with borehole monitoring data. - Abstract: Grouting of water-conducting fractures with low-alkali cement is foreseen for the potential future repository for spent nuclear fuel in Finland (ONKALO). A possible consequence of the interaction between groundwater and grout is the formation of high-pH solutions which will be able to react with the host rock (gneisses) and alter its mineralogy and porosity. A reactive transport modeling study of this possible alteration has been conducted. First, the hydration of the low-alkali cementitious grout has been modeled, using results from the literature as a guide. The hydrated cement is characterized by the absence of portlandite and the presence of a C-S-H gel with a Ca/Si ratio about 0.8 after tens of years (Ca/Si is about 1.7 in Ordinary Portland Cement). Second, calculations have simulated the interaction between flowing water and grout and the formation of an alkalinity plume, which flows beyond the grouted section of the fracture. The calculations include the hydration and simultaneous leaching of the grout through diffusive exchange between the porewater in the grout and the flowing water in the fracture. The formation of an alkaline plume is extremely limited when the low-pH grout is used. Even when using a grout with a lower silica fume content, the extent and magnitude of the alkaline plume is quite minor. These results are in qualitative agreement with monitoring at ONKALO.

  7. The radiation stability of glycine in solid CO2 - In situ laboratory measurements with applications to Mars

    Science.gov (United States)

    Gerakines, Perry A.; Hudson, Reggie L.

    2015-05-01

    The detection of biologically important, organic molecules on Mars is an important goal that may soon be reached. However, the current small number of organic detections at the martian surface may be due to the harsh UV and radiation conditions there. It seems likely that a successful search will require probing the subsurface of Mars, where penetrating cosmic rays and solar energetic particles dominate the radiation environment, with an influence that weakens with depth. Toward the goal of understanding the survival of organic molecules in cold radiation-rich environments on Mars, we present new kinetics data on the radiolytic destruction of glycine diluted in frozen carbon dioxide. Rate constants were measured in situ with infrared spectroscopy, without additional sample manipulation, for irradiations at 25, 50, and 75 K with 0.8-MeV protons. The resulting half-lives for glycine in CO2-ice are compared to previous results for glycine in H2O-ice and show that glycine in CO2-ice is much less stable in a radiation environment, with destruction rate constants ∼20-40 times higher than glycine in H2O-ice. Extrapolation of these results to conditions in the martian subsurface results in half-lives estimated to be less than 100-200 Myr even at depths of a few meters.

  8. In Situ Formation of AgCo Stabilized on Graphitic Carbon Nitride and Concomitant Hydrolysis of Ammonia Borane to Hydrogen.

    Science.gov (United States)

    Wang, Qi; Xu, Caili; Ming, Mei; Yang, Yingchun; Xu, Bin; Wang, Yi; Zhang, Yun; Wu, Jie; Fan, Guangyin

    2018-04-26

    The development of highly-efficient heterogeneous supported catalysts for catalytic hydrolysis of ammonia borane to yield hydrogen is of significant importance considering the versatile usages of hydrogen. Herein, we reported the in situ synthesis of AgCo bimetallic nanoparticles supported on g-C₃N₄ and concomitant hydrolysis of ammonia borane for hydrogen evolution at room temperature. The as-synthesized Ag 0.1 Co 0.9 /g-C₃N₄ catalysts displayed the highest turnover frequency (TOF) value of 249.02 mol H₂·(mol Ag ·min) −1 for hydrogen evolution from the hydrolysis of ammonia borane, which was higher than many other reported values. Furthermore, the Ag 0.1 Co 0.9 /g-C₃N₄ catalyst could be recycled during five consecutive runs. The study proves that Ag 0.1 Co 0.9 /g-C₃N₄ is a potential catalytic material toward the hydrolysis of ammonia borane for hydrogen production.

  9. In Situ Formation of AgCo Stabilized on Graphitic Carbon Nitride and Concomitant Hydrolysis of Ammonia Borane to Hydrogen

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2018-04-01

    Full Text Available The development of highly-efficient heterogeneous supported catalysts for catalytic hydrolysis of ammonia borane to yield hydrogen is of significant importance considering the versatile usages of hydrogen. Herein, we reported the in situ synthesis of AgCo bimetallic nanoparticles supported on g-C3N4 and concomitant hydrolysis of ammonia borane for hydrogen evolution at room temperature. The as-synthesized Ag0.1Co0.9/g-C3N4 catalysts displayed the highest turnover frequency (TOF value of 249.02 mol H2·(molAg·min−1 for hydrogen evolution from the hydrolysis of ammonia borane, which was higher than many other reported values. Furthermore, the Ag0.1Co0.9/g-C3N4 catalyst could be recycled during five consecutive runs. The study proves that Ag0.1Co0.9/g-C3N4 is a potential catalytic material toward the hydrolysis of ammonia borane for hydrogen production.

  10. Grout for closure of waste-disposal vaults at the US DOE Hanford Site

    International Nuclear Information System (INIS)

    Wakeley, L.D.; Ernzen, J.J.; McDaniel, E.W.; Voogd, J.

    1991-01-01

    For permanent disposal of radioactive wastes from reprocessing, the US Department of Energy (DOE) has chosen to grout wastes in concrete vaults within a subsurface multiple-barrier system. The subject of this research is the non-radioactive, or ''cold cap'' grout, which fills the upper 120 cm of these vaults, and provides support for overlying barriers. Because of the heat evolved by the wasteform, this void-filling grout must perform at temperatures higher than those of usual large-volume grouting operations. It must have: low potential for thermal expansion and heat retention; a low modulus to withstand thermal and mechanical stresses without cracking; strength adequate to support overlying barrier-system components; and minimal potential for shrinkage. In addition, it must be pumpable, self-leveling, and non-segregating. Materials for formulation included a large percentage of Class F fly ash, and coarsely ground oil-well cement. Grout development included chemical and physical characterization, and physical and thermal modeling

  11. Final report of the rock sealing project - Sealing properties and longevity of smectitic clay grouts

    International Nuclear Information System (INIS)

    Pusch, R.; Karnland, O.; Hoekmark, H.; Sanden, T.; Boergesson, L.

    1991-12-01

    Na and Ca bentonite clay grouts with densities that make them easily injected into fine fractures have been hydrothermally treated and investigated with respect to the hydraulic conductivity and shear strength. Exposure of the grouts to salt groundwater increased the hydraulic conductivity up to around 10 -5 m/s, which is on the same order of magnitude as the value at complete conversion of soft montmorillonite clay to hydrous mica, i.e. the major ultimate reaction product. Still, even this 'worst scenario' case will not lead to a higher bulk conductivity of the grouted rock than around 10 -10 m/s of rock with a conductivity of 10 -8 m/s before grouting. The rate of such conversion, which is entirely dependent on the potassium content of the groundwater, can be anything from a few hundred years to several thousand years depending primarily on the magnitude of prevailing hydraulic gradients. The shear strength of the grouts, which determines the resistance to piping and erosion, increases with time and temperature. The most critical situation is immediately after injection into the rock, when hydraulic gradients exceeding about 30 may produce piping. (au)

  12. Development and enhancement of grouting technologies in the Mizunami Underground Research Laboratory (Contract research)

    International Nuclear Information System (INIS)

    Nobuto, Jun; Mikake, Shinichiro

    2008-03-01

    In the Tono Geoscience Center of Japan Atomic Energy Agency (hereafter, JAEA), Mizunami Underground Research Laboratory project is being advanced to develop a scientific and technological basis for geological disposal. The concept of geological disposal is based on a multi-barrier system which combines a stable geological environment with an engineered barrier system (EBS). In order to develop a engineering basis for the construction of disposal system, the enhancement of grouting technologies among engineering technologies is needed. In this study, the comprehensive performance of suspension type grouting materials to seal rock fractures encountered in excavation works at deep underground has been checked, and the clogging phenomenon at the entrance of rock fractures has been investigated following the previous year. Research issues are as follows; Study on grouting concept to secure high-level water sealing, study on the test method to check grout clogging under high injection pressure, study on grouting material which can penetrate into finer fractures. Among these, in the study on penetrability test method, prototype test instruments were made and a series of preliminary tests were conducted. (author)

  13. Characterization results for 106-AN grout produced in a pilot-scale test

    International Nuclear Information System (INIS)

    Lokken, R.O.; Bagaasen, L.M.; Martin, P.F.C.; Palmer, S.E.; Anderson, C.M.

    1993-06-01

    The Grout Treatment Facility (GTF) at Hanford. Washington, will process the low-level fraction of selected double-shell tank (DST) wastes into a cementitious waste form. This facility, which is operated by Westinghouse Hanford Company (WHC), mixes liquid waste with cementitious materials to produce a waste form that immobilizes hazardous constituents through chemical reactions and/or microencapsulation. Over one million gallons of phosphate/sulfate waste were solidified in the first production campaign with this facility. The next tank waste scheduled for treatment is 106-AN (the waste from Tank 241-AN-106). After laboratory studies were conducted to select the grout formulation, tests using the 1/4-scale pilot facilities at the Pacific Northwest Laboratory (PNL) were conducted as part of the formulation verification process. The major objectives of these pilot-scale tests were to determine if the proposed grout formulation could be processed in the pilotscale equipment. to collect thermal information to help determine the best way to manage the grout hydration heat, and to characterize the solidified grout

  14. In situ growth of hollow gold-silver nanoshells within porous silica offers tunable plasmonic extinctions and enhanced colloidal stability.

    Science.gov (United States)

    Li, Chien-Hung; Jamison, Andrew C; Rittikulsittichai, Supparesk; Lee, Tai-Chou; Lee, T Randall

    2014-11-26

    Porous silica-coated hollow gold-silver nanoshells were successfully synthesized utilizing a procedure where the porous silica shell was produced prior to the transformation of the metallic core, providing enhanced control over the structure/composition of the bimetallic hollow core. By varying the reaction time and the precise amount of gold salt solution added to a porous silica-coated silver-core template solution, composite nanoparticles were tailored to reveal a readily tunable surface plasmon resonance that could be centered across the visible and near-IR spectral regions (∼445-800 nm). Characterization by X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy revealed that the synthetic methodology afforded particles having uniform composition, size, and shape. The optical properties were evaluated by absorption/extinction spectroscopy. The stability of colloidal solutions of our composite nanoparticles as a function of pH was also investigated, revealing that the nanoshells remain intact over a wide range of conditions (i.e., pH 2-10). The facile tunability, enhanced stability, and relatively small diameter of these composite particles (∼110 nm) makes them promising candidates for use in tumor ablation or as photothermal drug-delivery agents.

  15. The Evaluation of Material Properties of Low-pH Cement Grout for the Application of Cementitious Materials to Deep Radioactive Waste Repository Tunnels

    International Nuclear Information System (INIS)

    Kim, Jin Seop; Kwon, S. K.; Cho, W. J.; Kim, G. W.

    2009-12-01

    Considering the current construction technology and research status of deep repository tunnels for radioactive waste disposal, it is inevitable to use cementitious materials in spite of serious concern about their long-term environmental stability. Thus, it is an emerging task to develop low pH cementitious materials. This study reviews the state of the technology on low pH cements developed in Sweden, Switzerland, France, and Japan as well as in Finland which is constructing a real deep repository site for high-level radioactive waste disposal. Considering the physical and chemical stability of bentonite which acts as a buffer material, a low pH cement limits to pH ≤11 and pozzolan-type admixtures are used to lower the pH of cement. To attain this pH requirement, silica fume, which is one of the most promising admixtures, should occupy at least 40 wt% of total dry materials in cement and the Ca/Si ratio should be maintained below 0.8 in cement. Additionally, selective super-plasticizer needs to be used because a high amount of water is demanded from the use of a large amount of silica fume. In this report, the state of the technology on application of cementitious materials to deep repository tunnels for radioactive waste disposal was analysed. And the material properties of low-pH and high-pH cement grouts were evaluated base on the grout recipes of ONKALO in Finlan

  16. Structural changes and thermal stability of charged LiNixMnyCozO₂ cathode materials studied by combined in situ time-resolved XRD and mass spectroscopy.

    Science.gov (United States)

    Bak, Seong-Min; Hu, Enyuan; Zhou, Yongning; Yu, Xiqian; Senanayake, Sanjaya D; Cho, Sung-Jin; Kim, Kwang-Bum; Chung, Kyung Yoon; Yang, Xiao-Qing; Nam, Kyung-Wan

    2014-12-24

    Thermal stability of charged LiNixMnyCozO2 (NMC, with x + y + z = 1, x:y:z = 4:3:3 (NMC433), 5:3:2 (NMC532), 6:2:2 (NMC622), and 8:1:1 (NMC811)) cathode materials is systematically studied using combined in situ time-resolved X-ray diffraction and mass spectroscopy (TR-XRD/MS) techniques upon heating up to 600 °C. The TR-XRD/MS results indicate that the content of Ni, Co, and Mn significantly affects both the structural changes and the oxygen release features during heating: the more Ni and less Co and Mn, the lower the onset temperature of the phase transition (i.e., thermal decomposition) and the larger amount of oxygen release. Interestingly, the NMC532 seems to be the optimized composition to maintain a reasonably good thermal stability, comparable to the low-nickel-content materials (e.g., NMC333 and NMC433), while having a high capacity close to the high-nickel-content materials (e.g., NMC811 and NMC622). The origin of the thermal decomposition of NMC cathode materials was elucidated by the changes in the oxidation states of each transition metal (TM) cations (i.e., Ni, Co, and Mn) and their site preferences during thermal decomposition. It is revealed that Mn ions mainly occupy the 3a octahedral sites of a layered structure (R3̅m) but Co ions prefer to migrate to the 8a tetrahedral sites of a spinel structure (Fd3̅m) during the thermal decomposition. Such element-dependent cation migration plays a very important role in the thermal stability of NMC cathode materials. The reasonably good thermal stability and high capacity characteristics of the NMC532 composition is originated from the well-balanced ratio of nickel content to manganese and cobalt contents. This systematic study provides insight into the rational design of NMC-based cathode materials with a desired balance between thermal stability and high energy density.

  17. Modelling the Small Throw Fault Effect on the Stability of a Mining Roadway and Its Verification by In Situ Investigation

    Directory of Open Access Journals (Sweden)

    Małkowski Piotr

    2017-12-01

    Full Text Available The small throw fault zones cause serious problems for mining engineers. The knowledge about the range of fractured zone around the roadway and about roadway’s contour deformations helps a lot with the right support design or its reinforcement. The paper presents the results of numerical analysis of the effect of a small throw fault zone on the convergence of the mining roadway and the extent of the fracturing induced around the roadway. The computations were performed on a dozen physical models featuring various parameters of rock mass and support for the purpose to select the settings that reflects most suitably the behavior of tectonically disturbed and undisturbed rocks around the roadway. Finally, the results of the calculations were verified by comparing them with in situ convergence measurements carried out in the maingate D-2 in the “Borynia-Zofiówka-Jastrzębie” coal mine. Based on the results of measurements it may be concluded that the rock mass displacements around a roadway section within a fault zone during a year were four times in average greater than in the section tectonically unaffected. The results of numerical calculations show that extent of the yielding zone in the roof reaches two times the throw of the fault, in the floor 3 times the throw, and horizontally approx. 1.5 to 1.8 times the width of modelled fault zone. Only a few elasto-plastic models or models with joints between the rock beds can be recommended for predicting the performance of a roadway which is within a fault zone. It is possible, using these models, to design the roadway support of sufficient load bearing capacity at the tectonically disturbed section.

  18. Effects of hydrated lime on radionuclides stabilization of Hanford tank residual waste.

    Science.gov (United States)

    Wang, Guohui; Um, Wooyong; Cantrell, Kirk J; Snyder, Michelle M V; Bowden, Mark E; Triplett, Mark B; Buck, Edgar C

    2017-10-01

    Chemical stabilization of tank residual waste is part of a Hanford Site tank closure strategy to reduce overall risk levels to human health and the environment. In this study, a set of column leaching experiments using tank C-104 residual waste were conducted to evaluate the leachability of uranium (U) and technetium (Tc) where grout and hydrated lime were applied as chemical stabilizing agents. The experiments were designed to simulate future scenarios where meteoric water infiltrates through the vadose zones into the interior of the tank filled with layers of grout or hydrated lime, and then contacts the residual waste. Effluent concentrations of U and Tc were monitored and compared among three different packing columns (waste only, waste + grout, and waste + grout + hydrated lime). Geochemical modeling of the effluent compositions was conducted to determine saturation indices of uranium solid phases that could control the solubility of uranium. The results indicate that addition of hydrated lime strongly stabilized the uranium through transforming uranium to a highly insoluble calcium uranate (CaUO 4 ) or similar phase, whereas no significant stabilization effect of grout or hydrated lime was observed on Tc leachability. The result implies that hydrated lime could be a great candidate for stabilizing Hanford tank residual wastes where uranium is one of the main concerns. Published by Elsevier Ltd.

  19. Effect of hygrothermal conditioning on the mechanical and thermal properties of epoxy grouts for offshore pipeline rehabilitation

    Directory of Open Access Journals (Sweden)

    Allan Manalo

    2016-07-01

    Full Text Available Offshore oil and gas pipelines are susceptible to corrosion and need rehabilitation to keep them operating in-service conditions. Fibre composite filled with epoxy-based grout is emerging as an effective repair and rehabilitation system for offshore pipelines performing underwater. In such applications, the infill grout is often subjected to moisture and elevated temperature along with compressive, tensile and localised stresses at the defect. Current standards and practices for composite repairs suggest detailed investigation of the fibre reinforced sleeve, while the characterisation of the infill material is yet to be conducted for performance evaluation. The present work investigates the mechanical and thermal properties of three epoxy grouts as candidates for infill in a grouted sleeve repair for underwater pipeline. An understanding on the effect of hygrothermal ageing on the grout properties for defining the period of 1000 hours as “long-term” according to ISO/TS 24817, in comparison to their unconditioned state, is also presented. The compressive and tensile strength of the unconditioned grouts ranges from 100–120 MPa, and 19–32 MPa, respectively, which indicates that these grouts are suitable for structural rehabilitation of the pipelines. Moreover, the glass transition temperatures, Tg and Tt of the unconditioned grouts are found to be within the ranges of 50–60 °C, and 80–90 °C, respectively, which are reduced by about 20°C after conditioning.

  20. The effect of using different sources of dry materials on waste-form grout properties

    International Nuclear Information System (INIS)

    Spence, R.D.; Gilliam, T.M.; McDaniel, E.W.

    1992-01-01

    A reference grout formulation had been developed for a liquid low-level radioactive waste using the following dry materials: ground limestone, ground granulated blast furnace slag, fly ash, and cement. The effect of varying the sources of these dry materials was tested. Two limestones, two fly ashes, two cements, and eight slags were tested. Varying the source of dry materials significantly affected the grout properties, but only the 28-d free-standing liquid varied outside of the preferred range. A statistical technique, Tukey's paired comparison, can be used to ascertain whether a given combination of dry materials resulted in grout properties significantly different from those of other combinations of dry materials. (author)

  1. Development of grout formulations for 106-AN waste: Mixture-experiment results and analysis

    International Nuclear Information System (INIS)

    Spence, R.D.; McDaniel, E.W.; Anderson, C.M.; Lokken, R.O.; Piepel, G.F.

    1993-09-01

    Twenty potential ingredients were identified for use in developing a 106-AN grout formulation, and 18 were subsequently obtained and tested. Four ingredients-Type II-LA (moderate heat of hydration) Portland cement, Class F fly ash, attapulgite 150 drilling clay, and ground air-cooled blast-furnace slag (GABFS) were selected for developing the 106-AN grout formulations. A mixture experiment was designed and conducted around the following formulation: 2.5 lb of cement per gallon, 1.2 lb of fly ash per gallon, 0.8 lb of attapulgite per gallon, and 3.5 lb of GABFS per gallon. Reduced empirical models were generated from the results of the mixture experiment. These models were used to recommend several grout formulations for 106-AN. Westinghouse Hanford Company selected one of these formulations to be verified for use with 106-AN and a backup formulation in case problems arise with the first choice

  2. Acid mine drainage abatement resulting from pressure grouting of buried bituminous mine spoils

    International Nuclear Information System (INIS)

    Scheetz, B.; Silsbee, M.; Schueck, J.

    1998-01-01

    A 37 acre surface coal mine located in Clinton County, PA, USA, was mined and reclaimed between 1974 and 1977. Buried pyrite-rich pit floor cleanings and tipple refuse were found to be producing severe acid mine drainage. The pyritic material is located in discrete piles or pods in the backfill. The pods and the resulting contaminant plumes were initially defined using geophysical techniques and confirmed by drilling. The approach taken was to use a cementitious grout, composed of fluidized bed combustion ash and water, which would be placed in a manner which would prevent water and oxygen from contacting the pyritic materials. Statistically significant water quality improvements have been noted as a result of the grouting. After four years of post-grouting monitoring, reductions in concentrations of most of the mine drainage parameters range from 40 to 90%. 12 refs., 1 fig., 4 tabs

  3. Field testing of jet-grouted pile : [summary].

    Science.gov (United States)

    2014-01-01

    In many areas of Florida, local geology dictates the use of deep foundations for transportation structures bridges, noise walls, signage, etc. When concrete piles are used, they are either prestressed at the casting yard, cast in situ through a h...

  4. Hybrid life cycle assessment comparison of colloidal silica and cement grouted soil barrier remediation technologies.

    Science.gov (United States)

    Gallagher, Patricia M; Spatari, Sabrina; Cucura, Jeffrey

    2013-04-15

    Site remediation involves balancing numerous costs and benefits but often neglects the environmental impacts over the entire project life cycle. Life cycle assessment (LCA) offers a framework for inclusion of global environmental "systems-level" decision metrics in combination with technological and cost analysis. We compare colloidal silica (CS) and cement grouted soil barrier remediation technologies for soils affected by low level radionuclides at a U.S. Superfund site using hybrid LCA methods. CS is a new, high performance grouting material installed using permeation grouting techniques. Cement, a more traditional grouting material, is typically installed using jet grouting techniques. Life cycle impacts were evaluated using the US EPA TRACI 2 model. Results show the highest life cycle environmental impacts for the CS barrier occur during materials production and transportation to the site. In general, the life cycle impacts for the cement barrier were dominated by materials production; however, in the extreme scenario the life cycle impacts were dominated by truck transportation of spoils to a distant, off-site radioactive waste facility. It is only in the extreme scenario tested in which soils are transported by truck (Option 2) that spoils waste transport dominates LCIA results. Life cycle environmental impacts for both grout barriers were most sensitive to resource input requirements for manufacturing volumes and transportation. Uncertainty associated with the efficacy of new technology such as CS over its required design life indicates that barrier replacement could increase its life cycle environmental impact above that of the cement barrier. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. High impact of in situ dextran coating on biocompatibility, stability and magnetic properties of iron oxide nanoparticles.

    Science.gov (United States)

    Shaterabadi, Zhila; Nabiyouni, Gholamreza; Soleymani, Meysam

    2017-06-01

    Biocompatible ferrofluids based on dextran coated iron oxide nanoparticles were fabricated by conventional co-precipitation method. The experimental results show that the presence of dextran in reaction medium not only causes to the appearance of superparamagnetic behavior but also results in significant suppression in saturation magnetization of dextran coated samples. These results can be attributed to size reduction originated from the role of dextran as a surfactant. Moreover, weight ratio of dextran to magnetic nanoparticles has a remarkable influence on size and magnetic properties of nanoparticles, so that the sample prepared with a higher weight ratio of dextran to nanoparticles has the smaller size and saturation magnetization compare with the other samples. In addition, the ferrofluids containing such nanoparticles have an excellent stability at physiological pH for several months. Furthermore, the biocompatibility studies reveal that surface modification of nanoparticles by dextran dramatically decreases the cytotoxicity of bare nanoparticles and consequently improves their potential application for diagnostic and therapeutic purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Research on Anchorage Performance of Grouting Anchor Connection of Precast Concrete Structure

    Science.gov (United States)

    Wang, Donghui; Liu, Xudong; Wang, Sheng; Cao, Xixi

    2018-03-01

    The bonding of grouted anchor bars is one of the vertical connection forms of steel bars in fabricated concrete structures. The performance of grouted connection is mainly affected by the anchorage length and lap length of steel bars. The mechanisms of bond and anchorage between steel bar and concrete are analyzed, and the factors that influence the anchorage performance of steel bar are systematically summarized. Results show that the bond and anchorage performance of steel and concrete have been studied widely, but there are still shortcomings, and the connection forms need to be further improved.

  7. Analysis on pile testing results of post-grouting bored pile

    Science.gov (United States)

    Zheng, A. R.

    2017-04-01

    Based on static load test results, the bearing capacity of bored piles with pile-toe and pile-shaft post-grouting has been analyzed. The analysis reveals that: with post-grouting, the interface between pile and surrounding soil are strengthened and the relative sliding displacement in between is reduced; end resistance of pile is enhanced and can be mobilized at earlier stage with smaller sliding displacement. As a result, the performance of bored pile is improved with increased bearing capacity and reduced settlement.

  8. Application of high-strength non-shrink cement based grouting material in nuclear power installations

    International Nuclear Information System (INIS)

    Li Zhong; Zuo Weiwei

    2011-01-01

    This paper briefly describes the related technical requirement of secondary grouting during the process of equipment installation in nuclear power projects. The method and procedure are introduced in detail from the aspects of acceptance, preparation, pouring, collecting and maintenance of the high-strength non-shrinking based pouring cement material, and the cautions during the construction is also provided. The factors affecting the quality of the field grouting is analyzed, and the measures to reduce or eliminate the micro-cracks during the process is provided. (authors)

  9. Research on cement-based grouts for the OECD/NEA international Stripa project

    International Nuclear Information System (INIS)

    Onofrei, M.

    1994-01-01

    This paper deals with the work that has been carried out on cement-based by AECL research in Canada. The results indicate that it is possible to manufacture low water content high-performance cement-grouts, the performance of which would be acceptable for at least thousands of years and probably for much longer periods. Moreover, these grouts were shown to have negligible hydraulic conductivity, associated with very low porosity and to be highly leach resistant in repository conditions. (TEC). 18 refs., 1 tab., 6 figs

  10. Bolt-Grout Interactions in Elastoplastic Rock Mass Using Coupled FEM-FDM Techniques

    Directory of Open Access Journals (Sweden)

    Debasis Deb

    2010-01-01

    Full Text Available Numerical procedure based on finite element method (FEM and finite difference method (FDM for the analysis of bolt-grout interactions are introduced in this paper. The finite element procedure incorporates elasto-plastic concepts with Hoek and Brown yield criterion and has been applied for rock mass. Bolt-grout interactions are evaluated based on finite difference method and are embedded in the elasto-plastic procedures of FEM. The experimental validation of the proposed FEM-FDM procedures and numerical examples of a bolted tunnel are provided to demonstrate the efficacy of the proposed method for practical applications.

  11. Validation of an in situ solidification/stabilization technique for hazardous barium and cyanide waste for safe disposal into a secured landfill.

    Science.gov (United States)

    Vaidya, Rucha; Kodam, Kisan; Ghole, Vikram; Surya Mohan Rao, K

    2010-09-01

    The aim of the present study was to devise and validate an appropriate treatment process for disposal of hazardous barium and cyanide waste into a landfill at a Common Hazardous Waste Treatment Storage Disposal Facility (CHWTSDF). The waste was generated during the process of hardening of steel components and contains cyanide (reactive) and barium (toxic) as major contaminants. In the present study chemical fixation of the contaminants was carried out. The cyanide was treated by alkali chlorination with calcium hypochlorite and barium by precipitation with sodium sulfate as barium sulfate. The pretreated mixture was then solidified and stabilized by binding with a combination of slag cement, ordinary Portland cement and fly ash, molded into blocks (5 x 5 x 5 cm) and cured for a period of 3, 7 and 28 days. The final experiments were conducted with 18 recipe mixtures of waste + additive:binder (W:B) ratios. The W:B ratios were taken as 80:20, 70:30 and 50:50. The optimum proportions of additives and binders were finalized on the basis of the criteria of unconfined compressive strength and leachability. The leachability studies were conducted using the Toxicity Characteristic Leaching Procedure. The blocks were analyzed for various physical and leachable chemical parameters at the end of each curing period. Based on the results of the analysis, two recipe mixtures, with compositions - 50% of [waste + (120 g Ca(OCl)(2) + 290 g Na(2)SO(4)) kg(-1) of waste] + 50% of binders, were validated for in situ stabilization into a secured landfill of CHWTSDF. 2010 Elsevier Ltd. All rights reserved.

  12. In-Situ Subsurface Coating of Corroded Steel Sheet Pile Structures: Final Report on Project F08-AR06

    Science.gov (United States)

    2017-09-01

    shrink cement grout or epoxy resin in the gap between old and new steel , shown in Figure 19. This was the reason why the perforated piles needed to...be made liquid-tight with cement grout or epoxy. Other- wise, the material injected between the old and new steel would be lost be- hind the old steel ...ER D C/ CE RL T R- 17 -3 5 DoD Corrosion Prevention and Control Program In-Situ Subsurface Coating of Corroded Steel Sheet Pile

  13. In Situ formation of pentafluorophosphate benzimidazole anion stabilizes high-temperature performance of lithium-ion batteries

    International Nuclear Information System (INIS)

    Pradanawati, Sylvia Ayu; Wang, Fu-Ming; Rick, John

    2014-01-01

    Highlights: • A new pentafluorophosphate benzimidazole anion was formed by Lewis acid-base reaction. • This pentafluorophosphate benzimidazole anion is fabricated with the benzimidazole anion and PF 5 . • This pentafluorophosphate benzimidazole anion avoids the ominous side reactions that PF 5 reacts SEI to form LiF and HF at high temperature. • The additional pentafluorophosphate benzimidazole anion formation well maintains the battery performance at 60 °C measurement compares to the electrolyte only with contains the salt, LiPF 6 . - Abstract: Lithium salts play a critical role in initiating electrochemical reactions in Li-ion batteries. Single Li ions dissociate from bulk-salt and associate with carbonates to form a solid electrolyte interface (SEI) during the first charge-discharge of the battery. SEI formation and the chemical stability of salt must both be controlled and optimized to minimize irreversible reactions in SEI formation and to suppress the decomposition of the salt at high temperatures. This study synthesizes a new benzimidazole-based anion in the electrolyte. This anion, pentafluorophosphate benzimidazole, results from a Lewis acid-base reaction between the benzimidazole anion and PF 5 . The new pentafluorophosphate benzimidazole anion inhibits the decomposition of LiPF 6 by inhibiting PF 5 side reactions, which degrade the SEI, and lead to the formation of LiF and HF at high temperatures. In addition, the use of the pentafluorophosphate benzimidazole anion results in the formation of a modified SEI that is able to modify the battery's performance. Cyclic voltammetry, scanning electron microscopy, differential scanning calorimetry, electrochemical impedance spectroscopy, as well as charge-discharge and X-ray photoelectron spectroscopy measurements have been used to characterize the materials in this study. The formation of the pentafluorophosphate benzimidazole anion in the electrolyte caused a 14% decrease in the activation energy

  14. Development of grouting technologies for geological disposal of high level waste in Japan (1). Overall program and application of developed technologies

    International Nuclear Information System (INIS)

    Fujita, Tomoo; Sasamoto, Hiroshi; Sugita, Yutaka; Matsui, Hiroya

    2013-01-01

    The Japan Atomic Energy Agency started a grout project for geological disposal of high-level radioactive waste (HLW) in 2007. The aim of the project was to develop new grouting technologies and grout materials and also to develop models for performance assessments, prediction of the long-term radionuclide migration and identify detrimental changes in the host rock by the grout material leachate. This study presents the overall program and the application of key engineering technologies to the construction and operation of an underground facility for the geological disposal of HLW, with particular emphasis on the long-term effects of grout materials. (author)

  15. In situ and real-time atomic force microscopy studies of the stability of oligothiophene langmuir-blodgett monolayers in liquid

    KAUST Repository

    Yin, Naining

    2014-03-20

    Oligothiophene thin films have been considered as promising material for molecular electronics due to their desirable electronic properties and high structural stability under ambient conditions. To ensure performance in devices the functional structures, such as individual ordered domains, must be stable under practical and operational conditions or environments including exposure to various media. This work investigates the structure of oligothiophene Langmuir-Blodgett (LB) films upon exposure to liquid media such as water, ethanol (EtOH), and mixed tetrahydrofuran (THF)/EtOH solutions. The LB films form islands ranging from 500 nm up to 1 μm consisting of densely packed oligothiophene molecules. These islands are surrounded by bare substrate and loosely packed adsorbates. In situ and time-dependent AFM images were acquired to reveal the structural evolution, from which degradation pathways and kinetics are extracted. Degradation of these LB films initiates and propagates from intraisland defect sites, such as cracks and pin holes, whereas the edges of islands remain intact on the surface. The observations appear to be in contrast to the known degradation mechanism among self-assembled monolayers, such as alkanethiols on gold, which initiates and progresses at domain boundaries. Rationale for the observed degradation processes will also be discussed. © 2014 American Chemical Society.

  16. Structural stability and self-healing capability of Er2O3 in situ coating on V-4Cr-4Ti in liquid lithium

    International Nuclear Information System (INIS)

    Yao, Zhenyu; Suzuki, Akihiro; Muroga, Takeo; Nagasaka, Takuya

    2006-01-01

    The in situ Er 2 O 3 insulating coating is under development for the self-cooled Li/V-alloy type fusion blanket. In this study, the structural stability and self-healing capability of the coating are investigated. Since the cracking in the coating was not observed after exposure when Li was removed with a weak lotion (liquid NH 3 ), the cracking observed in the previous studies is not a practical issue in a real blanket. The re-exposure of the coating in pure Li showed that the coating once formed in Li (Er) is thought to be stable in pure Li. Thus, coating has the possibility to be serviced in a Li environment without an Er supply. By prior exposure to Li (Er) at 873 K, the exhaustion of the oxygen storage in V-alloy substrate during exposure at 973 K could be delayed effectively. The self-healing capability of the coating was demonstrated by the examination with the re-exposing cracked coating in Li (Er)

  17. Incorporation of low energy activated nitrogen onto HOPG surface: Chemical states and thermal stability studies by in-situ XPS and Raman spectroscopy

    Science.gov (United States)

    Chandran, Maneesh; Shasha, Michal; Michaelson, Shaul; Hoffman, Alon

    2016-09-01

    In this paper we report the chemical states analysis of activated nitrogen incorporated highly oriented pyrolytic graphite (HOPG) surface under well-controlled conditions. Nitrogen incorporation is carried out by two different processes: an indirect RF nitrogen plasma and low energy (1 keV) N2+ implantation. Bonding configuration, concentration and thermal stability of the incorporated nitrogen species by aforesaid processes are systematically compared by in-situ X-ray photoelectron spectroscopy (XPS). Relatively large concentration of nitrogen is incorporated onto RF nitride HOPG surface (16.2 at.%), compared to N2+ implanted HOPG surface (7.7 at.%). The evolution of N 1s components (N1, N2, N3) with annealing temperature is comprehensively discussed, which indicates that the formation and reorganization of local chemical bonding states are determined by the process of nitridation and not by the prior chemical conditioning (i.e., amorphization or hydrogenation) of the HOPG surface. A combined XPS and Raman spectroscopy studies revealed that N2+ implantation process resulted in a high level of defects to the HOPG surface, which cannot be annealed-out by heat treatment up to 1000 °C. On the other hand, the RF nitrogen plasma process did not produce a high level of surface defects, while incorporating nearly the same amount of stable nitrogen species.

  18. In-situ grown CNTs modified SiO2/C composites as anode with improved cycling stability and rate capability for lithium storage

    Science.gov (United States)

    Wang, Siqi; Zhao, Naiqin; Shi, Chunsheng; Liu, Enzuo; He, Chunnian; He, Fang; Ma, Liying

    2018-03-01

    Silica (SiO2) is regarded as one of the most promising anode materials for lithium ion batteries owing to its high theoretical specific capacity, relatively low operation potentials, abundance, environmental benignity and low cost. However, the low intrinsic electrical conductivity and large volume change of SiO2 during the discharge/charge cycles usually results in poor electrochemical performance. In this work, carbon nanotubes (CNTs) modified SiO2/C composites have been fabricated through an in-situ chemical vapor deposition method. The results show that the electrical conductivity of the SiO2/C/CNTs is visibly enhanced through a robust connection between the CNTs and SiO2/C particles. Compared with the pristine SiO2 and SiO2/C composites, the SiO2/C/CNTs composites display a high initial capacity of 1267.2 mA h g-1. Besides, an excellent cycling stability with the capacity of 315.7 mA h g-1 is achieved after 1000th cycles at a rate of 1 A g-1. The significantly improved electrochemical properties of the SiO2/C/CNTs composites are mainly attributed to the formation of three dimensional CNT networks in the SiO2/C substrate, which can not only shorten the Li-ion diffusion path but also relieve the volume change during the lithium-ion insertion/extraction processes.

  19. A two-stage ceramic tile grout sealing process using a high power diode laser—Grout development and materials characteristics

    Science.gov (United States)

    Lawrence, J.; Li, L.; Spencer, J. T.

    1998-04-01

    Work has been conducted using a 60 Wcw high power diode laser (HPDL) in order to determine the feasibility and characteristics of sealing the void between adjoining ceramic tiles with a specially developed grout material having an impermeable enamel surface glaze. A two-stage process has been developed using a new grout material which consists of two distinct components: an amalgamated compound substrate and a glazed enamel surface; the amalgamated compound seal providing a tough, heat resistant bulk substrate, whilst the enamel provides an impervious surface. HPDL processing has resulted in crack free seals produced in normal atmospheric conditions. The basic process phenomena are investigated and the laser effects in terms of seal morphology, composition and microstructure are presented. Also, the resultant heat affects are analysed and described, as well as the effects of the shield gases, O 2 and Ar, during laser processing. Tiles were successfully sealed with power densities as low as 500 W/cm 2 and at rates up to 600 mm/min. Contact angle measurements revealed that due to the wettability characteristics of the amalgamated oxide compound grout (AOCG), laser surface treatment was necessary in order to alter the surface from a polycrystalline to a semi-amorphous structure, thus allowing the enamel to adhere. Bonding of the enamel to the AOCG and the ceramic tiles was identified as being principally due to van der Waals forces, and on a very small scale, some of the base AOCG material dissolving into the glaze.

  20. HYDRAULIC AND PHYSICAL PROPERTIES OF SALTSTONE GROUTS AND VAULT CONCRETES

    International Nuclear Information System (INIS)

    Dixon, K.; Harbour, J.; Phifer, M.

    2008-01-01

    were determined following a minimum 28 day curing period. Additional testing of the three saltstone formulations was conducted following a minimum 90 day curing period. The compressive strength of each saltstone and concrete material was measured at approximately 14, 28, 56, and 90 days. Recommended hydraulic property values for each saltstone grout and the vault concretes are provided. The hydraulic properties provided for each material include the saturated hydraulic conductivity, dry bulk density, particle density, and porosity. In addition, water retention data are presented for each material along with the van Genuchten transport parameters as determined using the RETC code

  1. Development programs in the United States of America for the application of cement-based grouts in radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    Dole, L.R.; Row, T.H.

    1984-01-01

    This paper briefly reviews seven cement-based waste form development programs at six of the US Department of Energy (DOE) sites. These sites have developed a variety of processes that range from producing 25 mm (1 in.) diameter pellets in a glove box to producing 240 m (800 ft.) diameter grout sheets within the bedding planes of a deep shale formation. These successful applications of cement-based waste forms to the many radioactive waste streams from nuclear facilities bear witness to the flexibility and reliability of this class of materials. This paper also discusses the major issues regarding the application of cement-based waste forms to radioactive waste management problems. These issues are (1) leachability, (2) radiation stability, (3) thermal stability, (4) phase complexity of the matrix, and (5) effects of the waste stream composition. A cursory review of current research in each of these areas is given This paper also discusses future trends in cement-based waste form development and applications. 31 references, 11 figures.

  2. Development programs in the United States of America for the application of cement-based grouts in radioactive waste management

    International Nuclear Information System (INIS)

    Dole, L.R.; Row, T.H.

    1984-01-01

    This paper briefly reviews seven cement-based waste form development programs at six of the US Department of Energy (DOE) sites. These sites have developed a variety of processes that range from producing 25 mm (1 in.) diameter pellets in a glove box to producing 240 m (800 ft.) diameter grout sheets within the bedding planes of a deep shale formation. These successful applications of cement-based waste forms to the many radioactive waste streams from nuclear facilities bear witness to the flexibility and reliability of this class of materials. This paper also discusses the major issues regarding the application of cement-based waste forms to radioactive waste management problems. These issues are (1) leachability, (2) radiation stability, (3) thermal stability, (4) phase complexity of the matrix, and (5) effects of the waste stream composition. A cursory review of current research in each of these areas is given This paper also discusses future trends in cement-based waste form development and applications. 31 references, 11 figures

  3. Reduction of Bacterial Pathogenic Risk during Ex-situ Stabilization of Previously Buried Foot-and-Mouth Disease Carcasses in a Pilot-scale Bio-augmented Aerobic Composting

    Science.gov (United States)

    Kim, S.; Park, J.; Park, J. K.; Park, S.; Jeon, H.; Kwon, H.

    2017-12-01

    Foot and mouth disease outbreaks globally occur. Although livestock suspected to be infected or actually infected by animal infectious diseases is typically treated with various methods including burial, burning, incineration, rendering, and composting, burial into soil is currently the major treatment method in Korea. However, buried carcasses are often found to remain undecomposed or incompletely decomposed even after the legal burial period (3 years). To reuse the land used for the burial purposes, Korea government is considering a novel approach to conduct in-situ burial treatment and then to move remaining carcasses from the burial sites to other sites designated for further ex-situ stabilization treatment (burial-composting sequential treatment). In this work, the feasibility of the novel approach was evaluated at a pilot scale facility. For the ex-situ stabilization, we tested the validity of use of a bio-augmented aerobic composting with carcass-degrading microorganisms, with emphasis on examining if the novel aerobic composting has reducing effects on potential pathogenic bacteria. As results, the decreased chemical oxygen demand (COD, 160,000 mg/kg to 40,000 mg/kg) and inorganic nitrogen species (total nitrogen, 5,000 mg/kg to 2,000 mg/kg) indicated effective bio-stabilization of carcasses. During the stabilization, bacterial community structure and dynamics determined by bacterial 16S rRNA sequencing were significantly changed. The prediction of potential pathogenic bacteria showed that bacterial pathogenic risk was significantly reduced up to a normal soil level during the ex-situ stabilization. The conclusion was confirmed by the following functional analysis of dominant bacteria using PICRUST. The findings support the microbiological safety of the ex-site use of the novel burial-composting sequential treatment. Acknowledgement : This study is supported by Korea Ministry of Environmental as "The GAIA Project"

  4. Expansive stresses of a grout plug on the walls of borehole

    International Nuclear Information System (INIS)

    Licastro, P.H.; Malek, R.I.A.; Roy, D.M.

    1985-01-01

    The primary function of a concrete plug in a repository seal system is to provide a viable seal at the interface with the host rock by developing and maintaining a positive normal stress across the interface. While standards do exist for unrestrained and restrained expansion of mortar and concrete there are few systems that permit calculation of stress for a stimulated borehole geometry. A system was designed to determine the radial stresses introduced by expansive, cementitious grout on the borehole. It consists of a strain gage instrumented cell and its associated signal conditioner/amplifier. Cell material and thickness can be varied to simulate restraining conditions at given depths. Prior to sample emplacement the cell/system is calibrated by fluid pressurization. Special cell design eliminates the effects of longitudinal stresses during calibration. An analog output as a function of time is recorded, in conjunction with surface temperature of the cylinder. The cell containing grout is maintained under controlled temperature conditions which can be varied from 25 0 C to 90 0 C. Pressure can be applied to the grout column to simulate hydrostatic/geostatic load conditions. Using the equipment described, several expansive grout formulations were studied at 38 0 C. Results obtained for expansive stresses as a function of time are presented together with implications on repository-seal durability

  5. Leach and EP [extraction procedure] toxicity tests on grouted waste from Tank 106-AN

    International Nuclear Information System (INIS)

    Serne, R.J.; Martin, W.J.; Lokken, R.O.; LeGore, V.L.; Lindenmeier, C.W.; Martin, P.F.C.

    1989-09-01

    Pacific Northwest Laboratory is conducting laboratory experiments to produce leach rate data for various waste species that will be contained in grout at Hanford. In the work reported here, grout made from Tank 106-AN liquid waste was used to produce empirical leach rate data for several radionuclides ( 60 Co, 90 Sr, 99Tc, 129I, 137Cs, and 241 Am), stable major components (NO 3 - , NO 2 - , F, Cl, and Na), and trace metals (Cr, Mo, and Ni). Two types of tests were used to produce leach rate data: an intermittent replacement leach test (ANS 16.1 leach test) and a static leach test. Measured effective diffusivities of key species are as follows: 4 to 6 x 10 -8 cm 2 /sec for 99 Tc, 3 to 7 x 10 -8 cm 2 /sec for 129 I, 4 to 6 x 10 -9 cm 2 /sec for nitrate, and 6 to 7 x 10 -9 cm 2 /sec for nitrite. The leach indices of all species studied are above (more favorable than) the waste form criteria. The leach indices for 99 Tc and 129 I are 7.4 ± 1.2 and 7.6 ± 0.4, respectively, and are being further investigated in continuing studies of double-shell slurry feed grouts. An Extraction Procedure (EP) toxicity test was also conducted and the grouted water is considered nontoxic per this test protocol. 19 refs., 9 figs., 8 tabs

  6. Performance assessment of grouted double-shell tank waste disposal at Hanford. Revision 1

    International Nuclear Information System (INIS)

    Shade, J.W., Kincaid, C.T.; Whyatt, G.A.; Rhoads, K.; Westsik, J.H. Jr.; Freshley, M.D.; Blanchard, K.A.; Shade, J.W.; Piepho, M.G.; Voogd, J.A.

    1994-09-01

    This document assesses the performance of the Grout Disposal Facility after closure. The facility and disposal environment are modeled to predict the long-term impacts of the disposal action. The document concludes that the disposal system provides reasonable assurance that doses to the public will remain within the performance objectives. This document is required for DOC Order 5820.2A

  7. Development of low alkaline cementitious grouting materials for a deep geological repository

    International Nuclear Information System (INIS)

    Suzuki, Kenichiro; Miura, Norihiko; Iriya, Keishiro; Kobayashi, Yasushi

    2012-01-01

    In order to reduce uncertainties of long-term safety assessment for a High Level radioactive Waste (HLW) repository system, low alkaline cementitious grouting materials have been studied. The pH of the leachate from the grouting material is targeted to be below 11.0, since the degradation of the bentonite buffer and host rock is limited. The current work focused on the effects of pozzolanic reactions to reduce pH and the development of low alkaline cementitious injection materials in which super-micro ordinary Portland cement (SOPC) was partially replaced by silica fume (SF), micro silica (MS) and fly ash (FA). As it is important to realize how the grouting material will respond to a high injection pressure into the fracture, and in order to understand the penetrability of different low alkaline cement mixes and to observe their flow behavior through the fracture, injection tests were conducted by using a simulated model fracture of 2 m diameter made from parallel plates of acrylic acid resin and stainless steel. Experimental results of the basic properties for selecting suitable materials and that of injecting into a simulated fracture to assess the grouting performance are described

  8. High-performance cement-based grouts for use in a nuclear waste disposal facility

    International Nuclear Information System (INIS)

    Onofrei, M.; Gray, M.N.

    1992-12-01

    National and international agencies have identified cement-based materials as prime candidates for sealing vaults that would isolate nuclear fuel wastes from the biosphere. Insufficient information is currently available to allow a reasonable analysis of the long-term performance of these sealing materials in a vault. A combined laboratory and modelling research program was undertaken to provide the necessary information for a specially developed high-performance cement grout. The results indicate that acceptable performance is likely for at least thousands of years and probably for much longer periods. The materials, which have been proven to be effective in field applications, are shown to be virtually impermeable and highly leach resistant under vault conditions. Special plasticizing additives used in the material formulation enhance the physical characteristics of the grout without detriment to its chemical durability. Neither modelling nor laboratory testing have yet provided a definitive assessment of the grout's longevity. However, none of the results of these studies has contraindicated the use of high-performance cement-based grouts in vault sealing applications. (Author) (24 figs., 6 tabs., 21 refs.)

  9. Time-Lapse Electrical Resistivity Investigations for Imaging the Grouting Injection in Shallow Subsurface Cavities

    Directory of Open Access Journals (Sweden)

    Muhammad Farooq

    2014-01-01

    Full Text Available The highway of Yongweol-ri, Muan-gun, south-western part of the South Korean Peninsula, is underlain by the abandoned of subsurface cavities, which were discovered in 2005. These cavities lie at shallow depths with the range of 5∼15 meters below the ground surface. Numerous subsidence events have repeatedly occurred in the past few years, damaging infrastructure and highway. As a result of continuing subsidence issues, the Korean Institute of Geosciences and Mineral Resources (KIGAM was requested by local administration to resolve the issue. The KIGAM used geophysical methods to delineate subsurface cavities and improve more refined understanding of the cavities network in the study area. Cement based grouting has been widely employed in the construction industry to reinforce subsurface ground. In this research work, time-lapse electrical resistivity surveys were accomplished to monitor the grouting injection in the subsurface cavities beneath the highway, which have provided a quasi-real-time monitoring for modifying the subsurface cavities related to ground reinforcement, which would be difficult with direct methods. The results obtained from time-lapse electrical resistivity technique have satisfactory imaged the grouting injection experiment in the subsurface cavities beneath the highway. Furthermore, the borehole camera confirmed the presence of grouting material in the subsurface cavities, and hence this procedure increases the mechanical resistance of subsurface cavities below the highway.

  10. Grouting applications in civil engineering. Volume I and II. [800 references

    Energy Technology Data Exchange (ETDEWEB)

    Einstein, H.H.; Barvenik, M.J.

    1975-01-01

    A comprehensive description of grouting applications in civil engineering is presented that can serve as a basis for the selection of grouting methods in the borehole sealing problem. The breadth and depth of the study was assured by conducting the main part of the review, the collection and evaluation of information, without specifically considering the borehole sealing problem (but naturally incorporating any aspect of civil engineering applications that could be of potential use). Grouting is very much an art and not a science. In most cases, it is a trial and error procedure where an inexpensive method is initially tried and then a more expensive one is used until the desired results are obtained. Once a desired effect is obtained, it is difficult to credit any one procedure with the success because the results are due to the summation of all the methods used. In many cases, the method that proves successful reflects a small abnormality in the ground or structure rather than its overall characteristics. Hence, successful grouting relies heavily on good engineering judgement and experience, and not on a basic set of standard correlations or equations. 800 references. (JRD)

  11. 106-AN grout pilot-scale test HGTP-93-0501-02

    International Nuclear Information System (INIS)

    Bagaasen, L.M.

    1993-05-01

    The Grout Treatment Facility (GTF) at Hanford, Washington will process the low-level fraction of selected double-shell tank (DST) wastes into a cementitious waste form. This facility, which is operated by Westinghouse Hanford Company (WHC), mixes liquid waste with cementitious materials to produce a waste form that immobilizes hazardous constituents through chemical reactions and/or microencapsulation. Over 1,000,000 gal of Phosphate/Sulfate Waste were solidified in the first production campaign with this facility. The next tank scheduled for treatment is 106-AN. After conducting laboratory studies to select the grout formulation, part of the normal formulation verification process is to conduct tests using the 1/4-scale pilot facilities at the Pacific Northwest Laboratory (PNL). The major objectives of these pilot-scale tests were to determine if the proposed grout formulation could be processed in the pilot-scale equipment and to collect thermal information to help determine the best way to manage the grout hydration heat

  12. Pretreatment of Tc-Containing Waste and Its Effect on Tc-99 Leaching From Grouts

    International Nuclear Information System (INIS)

    Aloy, Albert; Kovarskaya, Elena N.; Harbour, John R.; Langton, Christine A.; Holtzscheiter, E. William

    2007-01-01

    A salt solution (doped with Tc-99), that simulates the salt waste stream to be processed at the Saltstone Production Facility, was immobilized in grout waste forms with and without (1) ground granulated blast furnace slag and (2) pretreatment with iron salts. The degree of immobilization of Tc-99 was measured through monolithic and crushed grout leaching tests. Although Fe (+2) was shown to be effective in reducing Tc-99 to the +4 state, the strong reducing nature of the blast furnace slag present in the grout formulation dominated the reduction of Tc-99 in the cured grouts. An effective diffusion coefficient of 4.75 x 10 -12 (Leach Index of 11.4) was measured using the ANSI/ANS-16.1 protocol. The leaching results show that, even in the presence of a concentrated salt solution, blast furnace slag can effectively reduce pertechnetate to the immobile +4 oxidation state. The measured diffusivity was introduced into a flow and transport model (PORFLOW) to calculate the release of Tc-99 from a Saltstone Vault as a function of hydraulic conductivity of the matrix. (authors)

  13. Pilot-scale production of grout with simulated double-shell slurry feed. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, G.A.

    1994-08-01

    This report describes the pilot-scale production of grout with simulated double-shell slurry feed (DSSF) waste performed in November 1988, and the subsequent thermal behavior of the grout as it cured in a large, insulated vessel. The report was issued in draft form in April 1989 and comments were subsequently received; however, the report was not finalized until 1994. In finalizing this report, references or information gained after the report was drafted in April 1989 have not been incorporated to preserve the report`s historical perspective. This report makes use of criteria from Ridelle (1987) to establish formulation criteria. This document has since been superseded by a document prepared by Reibling and Fadeef (1991). However, the reference to Riddelle (1987) and any analysis based on its content have been maintained within this report. In addition, grout is no longer being considered as the waste form for disposal of Hanford`s low-level waste. However, grout disposal is being maintained as an option in case there is an emergency need to provide additional tank space. Current plans are to vitrify low-level wastes into a glass matrix.

  14. Research status and future trends on surface pre-grouting technology in reforming wall rock of vertical shafts in coal mines in China

    Science.gov (United States)

    Wang, Hua

    2018-02-01

    In the mine construction, the surface pre-grouting technology is an important method to prevent water blast in excavation process of vertical shaft when the shaft must pass through the thick, water-rich and high water-pressure bedrock aquifer. It has been nearly 60 years since the technology was used to reform wall rock of vertical shaft in coal mine in China for the first time, and the existing technology can basically meet the needs of constructing 1000m deep vertical shaft. Firstly, the article introduces that in view of Magg’s spherical seepage theory and Karol’s spherical seepage theory, Chinese scholars found that the diffusion of grout from borehole into the surrounding strata in horizontal direction is irregular through a lot of research and engineering practice of using the surface pre-grouting technology to reform wall rock of vertical shafts, and put forward the selecting principles of grout’s effective diffusion radius in one grouting engineering; Secondly, according to the shape of the grouting boreholes, surface pre-grouting technology of vertical shaft is divided into two stages: vertical borehole stage and S-type borehole stage. Thirdly, the development status of grouting materials and grouting equipment for the technology is introduced. Fourthly, grouting mode, stage height and pressure of the technology are introduced. Finally, it points out that with the increasing depth of coal mining in China, the technology of reforming wall rock of 1000~2000m deep vertical shafts will face many problems, such as grouting theory, grouting equipment, grouting finishing standard, testing and evaluation of grouting effect, and so on. And it put forward a preliminary approach to solving these problems. This paper points out future research directions of the surface pre-grouting technology in China.

  15. Technical performance of cementitious grouting materials for ONKALO. Laboratory tests 2006

    International Nuclear Information System (INIS)

    Raivio, P.; Hansen, J.

    2007-09-01

    During 2006 the development of high and low-pH cementitious grouts for fractures > 100 μm designed for the ONKALO rock was continued within the LPHTEK/IMAproject. The main focus in laboratory was to study high pH micro cement grouts. The low pH (≥ 11.0) of the cementitious grout material is required in deep repository as natural pH plume deriving from pure cement paste is very high and moves via ground water circulation in bedrock. This may be deleterious to the protective covers of nuclear waste. The objective to study high pH grouts in laboratory was to optimise their composition and to get preliminary test results. Low pH grouts based on Portland cement + micro silica were also studied further in laboratory to understand their behaviour more thoroughly in different conditions and due to quality changes in materials and to compare the laboratory results with the field results. Alternative fine-grained glass material was briefly studied to replace silica in low pH grout. Low and high pH rock bolt mortars were also developed and tested to get the preliminary test results. The results of the 2006 laboratory work are presented in this report. The high pH micro cement mix U1 with no silica, mix 5/5 with moderate silica and low pH mix P308B rich in silica show generally good properties at fresh and hardening stage at +12 deg C. Lower temperature gives weaker strength build-up with all the mixes and weakens especially the Marsh fluidity and penetration ability of the mixes 5/5 and P308B as bulk density rises a little at lower temperature. Cement quality variation and insufficient mixing may also weaken the properties of all mixes. Deformation of the hardened mixes was observed in laboratory tests. This may weaken their durability if cracks are formed in the grouts at later ages and need to be studied more thoroughly. (orig.)

  16. Finite Element Analysis of Grouting Compactness Monitoring in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

    Directory of Open Access Journals (Sweden)

    Tianyong Jiang

    2017-09-01

    Full Text Available With the development of the post-tensioning technique, prestressed concrete structures have been widely used in civil engineering. To ensure the long-term effectiveness of the prestressed tendon, the grouting quality of the tendon duct is one of the important factors. However, it is still a challenge to monitor the grouting quality of post-tensioning tendon ducts, due to the invisibility of the grouting. The authors’ previous work proposed a real-time method that employed a stress wave-based active sensing approach with piezoceramic transducers to monitor the grouting compactness of a Post-Tensioning Tendon Duct (PTTD. To further understand the piezoceramic induced stress wave propagation in the PTTD with different grouting levels, this paper develops a two-dimensional finite element model for monitoring the grouting compactness of the tendon duct with a piezoceramic transducer. A smart aggregate (SA developed to utilize one Lead Zirconate Titanate (PZT transducer with marble protection is installed in the center location of the tendon duct as an actuator. Two PZT patches are bonded on the bottom and top surface of the tendon duct as the sensors. The analysis results show that the finite element analysis results are in good agreement with the experimental results, which demonstrates that the finite element analysis is feasible and reliable. For the top half of the specimen, not much stress wave could be detected before the full grouting level, except for negligible signals that may propagate through the walls of the tendon duct. When the tendon duct grouting is at 100%, the stress wave propagates to the top of the specimen, and the displacements are symmetric in both left-right and top-bottom directions before the stress waves reach the boundary. The proposed two-dimensional finite element model has the potential to be implemented to simulate the stress wave propagation principle for monitoring grouting compaction of the post-tensioning tendon

  17. Development and application of new composite grouting material for sealing groundwater inflow and reinforcing wall rock in deep mine.

    Science.gov (United States)

    Jinpeng, Zhang; Limin, Liu; Futao, Zhang; Junzhi, Cao

    2018-04-04

    With cement, bentonite, water glass, J85 accelerator, retarder and water as raw materials, a new composite grouting material used to seal groundwater inflow and reinforce wall rock in deep fractured rock mass was developed in this paper. Based on the reaction mechanism of raw material, the pumpable time, stone rate, initial setting time, plastic strength and unconfined compressive strength of multi-group proportion grouts were tested by orthogonal experiment. Then, the optimum proportion of composite grouting material was selected and applied to the grouting engineering for sealing groundwater inflow and reinforcing wall rock in mine shaft lining. The results show the mixing proportion of the maximum pumpable time, maximum stone rate and minimum initial setting time of grout are A K4 B K1 C K4 D K2 , A K3 B K1 C K1 D K4 and A K3 B K3 C K4 D K1 , respectively. The mixing proportion of the maximum plastic strength and unconfined compressive strength of grouts concretion bodies are A K1 B K1 C K1 D K3 and A K1 B K1 C K1 D K1 , respectively. Balanced the above 5 indicators overall and determined the optimum proportion of grouts: bentonite-cement ratio of 1.0, water-solid ratio of 3.5, accelerator content of 2.9% and retarder content of 1.45%. This new composite grouting material had good effect on the grouting engineering for sealing groundwater inflow and reinforcing wall rock in deep fractured rock mass.

  18. Finite Element Analysis of Grouting Compactness Monitoring in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers.

    Science.gov (United States)

    Jiang, Tianyong; Zheng, Junbo; Huo, Linsheng; Song, Gangbing

    2017-09-29

    With the development of the post-tensioning technique, prestressed concrete structures have been widely used in civil engineering. To ensure the long-term effectiveness of the prestressed tendon, the grouting quality of the tendon duct is one of the important factors. However, it is still a challenge to monitor the grouting quality of post-tensioning tendon ducts, due to the invisibility of the grouting. The authors' previous work proposed a real-time method that employed a stress wave-based active sensing approach with piezoceramic transducers to monitor the grouting compactness of a Post-Tensioning Tendon Duct (PTTD). To further understand the piezoceramic induced stress wave propagation in the PTTD with different grouting levels, this paper develops a two-dimensional finite element model for monitoring the grouting compactness of the tendon duct with a piezoceramic transducer. A smart aggregate (SA) developed to utilize one Lead Zirconate Titanate (PZT) transducer with marble protection is installed in the center location of the tendon duct as an actuator. Two PZT patches are bonded on the bottom and top surface of the tendon duct as the sensors. The analysis results show that the finite element analysis results are in good agreement with the experimental results, which demonstrates that the finite element analysis is feasible and reliable. For the top half of the specimen, not much stress wave could be detected before the full grouting level, except for negligible signals that may propagate through the walls of the tendon duct. When the tendon duct grouting is at 100%, the stress wave propagates to the top of the specimen, and the displacements are symmetric in both left-right and top-bottom directions before the stress waves reach the boundary. The proposed two-dimensional finite element model has the potential to be implemented to simulate the stress wave propagation principle for monitoring grouting compaction of the post-tensioning tendon duct.

  19. Predictive tools and data needs for long term performance of in-situ stabilization and containment systems: DOE/OST stabilization workshop, June 26-27, Park City, Utah

    International Nuclear Information System (INIS)

    Borns, D.J.

    1997-01-01

    This paper summarizes the discussion within the Predictive Tools and Data Needs for Long Term Performance Assessment Subgroup. This subgroup formed at the DOE Office of Science and Technology workshop to address long-term performance of in situ stabilization and containment systems. The workshop was held in Park City, Utah, 26 and 27 June, 1996. All projects, engineering and environmental, have built-in decision processes that involve varying risk/reward scenarios. Such decision-processes maybe awkward to describe but are utilized every day following approaches that range from intuitive to advanced mathematical and numerical. Examples are the selection of components of home sound system, the members of a sports team, investments in a portfolio, and the members of a committee. Inherent in the decision method are an understanding of the function or process of the system requiring a decision or prediction, an understanding of the criteria on which decisions are made such as cost, performance, durability and verifiability. Finally, this process requires a means to judge or predict how the objects, activities, people and processes being analyzed will perform relative to the operations and functions of the system and relative to the decision criteria posed for the problem. These risk and decision analyses are proactive and iterative throughout the life of a remediation project. Prediction inherent to the analyses are based on intuition, experience, trial and error, and system analysis often using numerical approaches

  20. Mechanical Stability of Stratified Sediments along the upper continental Slope off Vesterålen, northern Norway - Insights from in situ CPTU Tests

    Science.gov (United States)

    Voelker, D.; Stegmann, S.; Kreiter, S.; L'Heureux, J. S.; Vanneste, M. W. B.; Baeten, N. J.; Knudsen, S.; Rise, L.; Longva, O.; Brendryen, J.; Haflidason, H.; Chand, S.; Mörz, T.; Kopf, A.

    2015-12-01

    High-resolution single channel-seismic data (3.5 kHz) reveal small-scale submarine landslide structures and superficial deformation features (e.g. tension cracks) along the gently dipping (3°) upper continental slope west of the Vesterålen Archipelago off northern Norway. Previous laboratory-based geotechnical studies attest that the slope is per sestable and that seismic events in an order of magnitude M5.7 may have triggered the slope sediments to fail. Here we present geotechnical in situ data (sedimentary strength, pore pressure), which were obtained with RV Poseidon in summer 2014 using the static CPTU system GOST. The CPTU system provided high-resolution geotechnical profiles of the uppermost sediments to a maximum penetration depth of ~ 20 m at six sites within the landslide features and beside them in undisturbed slope sediments as reference. The CPTU data reveal the occurrence of mechanically weaker zones (MWZ) by the drop of sedimentary strength. These zones are interbedded by coarser, more competent layers. The occurrence of sensitive fine-grained material may be responsible for the loss of strength in the deeper portion (appx. 12 to 18 m below seafloor). An 1D infinite pseudo-static stability analysis attests that the mechanically weaker zones (MWZ) correlate well with portions, where the Factor of Safety (FoS) ≤ 1 (meta-stable to unstable) indicates permanent deformation or failure in case additional dynamic load is induced by an earthquake. Thus, the mechanically weak layers can be considered as one important pre-condition for landslide activity. In conclusion, the integration of in situ CPTU data with geophysical data improves soil characterization and hence foster a better understanding of the pre-conditioning factors for slope instability at the upper continental slope off Vesterålen. Risk assessment for the present-day slope off Vesterålen is particularly crucial, because the opening of the region for offshore oil and gas exploration is

  1. D7.21 Report on Validation of design of grouted joints Work Package 7.2

    DEFF Research Database (Denmark)

    Rodriguez, Alvaro; Natarajan, Anand; Santos, Benjamin

    2017-01-01

    components. As offshore wind turbines reach 10 MW capacities, it is extremely important to determine the reliability of grouted joints and their design configurations so as to ensure integrity of the 10 MW support structure. This report investigates two types of grouted joint connections, the conventional...... cylindrical joint with shear keys and a conical joint without shear keys. In both cases, fully coupled load simulations are made to determine the fatigue resistance and ultimate load resistance of the joint. Key recommendations are made for the reliable design of grouted joints for 10 MW wind turbines...

  2. A one-step in-situ assembly strategy to construct PEG@MOG-100-Fe shape-stabilized composite phase change material with enhanced storage capacity for thermal energy storage

    Science.gov (United States)

    Wang, Junyong; Andriamitantsoa, Radoelizo S.; Atinafu, Dimberu G.; Gao, Hongyi; Dong, Wenjun; Wang, Ge

    2018-03-01

    A novel in-situ assembly strategy has been developed to synthesis polyethylene glycol (PEG)@iron-benzenetricarboxylate metal-organic gel (MOG-100-Fe) shape-stabilized composite phase change materials by regulating metal-to-ligand ratio. The PEG@MOG-100-Fe was prepared by an ingenious introduction of PEG into the traditional sol-gel prepared MOG-100-Fe. The composite exhibited high heat storage density and thermal stability. The PEG loading content reached up to 92% without any leakage above its melting point. The heat storage density reaches to 152.88

  3. Enhanced cycle stability of micro-sized Si/C anode material with low carbon content fabricated via spray drying and in situ carbonization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dingsheng; Gao, Mingxia, E-mail: gaomx@zju.edu.cn; Pan, Hongge; Liu, Yongfeng; Wang, Junhua; Li, Shouquan; Ge, Hongwei

    2014-08-01

    Highlights: • Micro-sized Si/C composites were fabricated via. spray drying and carbonization. • Multi-morphology carbon was formed in the Si/C composites. • Si/C composite with 5.6 wt.% C provides significant improved cycling stability. • Multi-morphology carbon plays effective role in improving the electrochemical property. • The method provides potential for mass production of superior Si-based anode materials. - Abstract: Micro-sized Si/C composites with in situ introduced carbon of multi-morphology were fabricated via spray drying a suspension of commercial micro-sized Si and citric acid followed by a carbonization. Different ratios of Si to citric acid were used to optimize the composition and structure of the composites and thus the electrochemical performance. Carbon flakes including crooked and flat ones were well dispersed in between the Si particles, forming Si/C composites. Floc-like carbon layers and carbon fragments were also found to cover partially the Si particles. The Si/C composite with a low carbon content of 5.6 wt.% provides an initial reversible capacity of 2700 mA h/g and a capacity of 1860 mA h/g after 60 cycles at a current density of 100 mA/g as anode material for lithium-ion batteries (LIBs), which are much higher than those of pristine Si and the Si/C composites with higher carbon content. The mechanism of the enhancement of electrochemical performance of the micro-sized Si/C composite is discussed. The fabrication method and the structure design of the composites offer valuable potential in developing adaptable Si-based anode materials for industrial applications.

  4. Wood-derived-biochar combined with compost or iron grit for in situ stabilization of Cd, Pb, and Zn in a contaminated soil.

    Science.gov (United States)

    Oustriere, Nadège; Marchand, Lilian; Rosette, Gabriel; Friesl-Hanl, Wolfgang; Mench, Michel

    2017-03-01

    In situ stabilization of Cd, Pb, and Zn in an Austrian agricultural soil contaminated by atmospheric depositions from a smelter plant was assessed with a pine bark chip-derived biochar, alone and in combination with either compost or iron grit. Biochar amendment was also trialed in an uncontaminated soil to detect any detrimental effect. The pot experiment consisted in ten soil treatments (% w/w): untreated contaminated soil (Unt); Unt soil amended with biochar alone (1%: B1; 2.5%: B2.5) and in combination: B1 and B2.5 + 5% compost (B1C and B2.5C), B1 and B2.5 + 1% iron grit (B1Z and B2.5Z); uncontaminated soil (Ctrl); Ctrl soil amended with 1 or 2.5% biochar (CtrlB1, CtrlB2.5). After a 3-month reaction period, the soil pore water (SPW) was sampled in potted soils and dwarf beans were grown for a 2-week period. The SPW Cd, Pb, and Zn concentrations decreased in all amended-contaminated soils. The biochar effects increased with its addition rate and its combination with either compost or iron grit. Shoot Cd and Zn removals by beans were reduced and shoot Cd, Pb, and Zn concentrations decreased to common values in all amended soils except the B1 soil. Decreases in the SPW Cd/Pb/Zn concentrations did not improve the root and shoot yields of plants as compared to the Ctrl soil.

  5. ASSESSMENT OF THE POTENTIAL FOR HYDROGEN GENERATION DURING GROUTING OPERATIONS IN THE R AND P REACTOR VESSELS

    Energy Technology Data Exchange (ETDEWEB)

    Wiersma, B.

    2010-05-24

    The R- and P-reactor buildings were retired from service and are now being prepared for deactivation and decommissioning (D and D). D and D activities consist primarily of immobilizing contaminated components and structures in a grout-like formulation. Aluminum corrodes very rapidly when it comes in contact with the alkaline grout materials and as a result produces hydrogen gas. To address this potential deflagration/explosion hazard, the Materials Science and Technology Directorate (MS and T) of the Savannah River National Laboratory (SRNL) has been requested to review and evaluate existing experimental and analytical studies of this issue to determine if any process constraints on the chemistry of the fill material and the fill operation are necessary. Various options exist for the type of grout material that may be used for D and D of the reactor vessels. The grout formulation options include ceramicrete (pH 6-8), low pH portland cement + silica fume grout (pH 10.4), or Portland cement groupt (pH 12.5). The assessment concluded that either ceramicrete or the silica fume grout may be used to safely grout the P-reactor vessel. The risk of accumulation of a flammable mixture of hydrogen between the grout-air interface and the top of the reactor is very low. Portland cement grout, on the other hand, for the same range of process parameters does not provide a margin of safety against the accumulation of flammable gas in the reactor vessel during grouting operations in the P-reactor vessel. It is recommended that this grout not be utilized for this task. The R-reactor vessel cotnains significantly less aluminum based on current facility process knowledge, surface observations, and drawings. Therefore, a Portland cement grout may be considered for grouting operations as well as the other grout formulations. For example, if the grout fill rate is less than 1 inch/min and the grout temperature is maintained at 70 C or less, the risk of hydrogen accumulation during fill

  6. Development of concrete mix proportions for minimizing/eliminating shrinkage cracks in slabs and high performance grouts : final report.

    Science.gov (United States)

    2017-02-01

    The two focus areas of this research address longstanding problems of (1) cracking of concrete slabs due to creep and shrinkage and (2) high performance compositions for grouting and joining precast concrete structural elements. Cracking of bridge de...

  7. A THERMAL MODEL OF THE IMMOBILIZATION OF LOW-LEVEL RADIOACTIVE WASTE AS GROUT IN CONCRETE VAULTS

    Energy Technology Data Exchange (ETDEWEB)

    Shadday, M

    2008-10-27

    Salt solution will be mixed with cement and flyash/slag to form a grout which will be immobilized in above ground concrete vaults. The curing process is exothermic, and a transient thermal model of the pouring and curing process is herein described. A peak temperature limit of 85 C for the curing grout restricts the rate at which it can be poured into a vault. The model is used to optimize the pouring.

  8. An Experimental Study of Portland Cement and Superfine Cement Slurry Grouting in Loose Sand and Sandy Soil

    Directory of Open Access Journals (Sweden)

    Weijing Yao

    2018-04-01

    Full Text Available Grouting technology is widely applied in the fields of geotechnical engineering in infrastructure. Loose sand and sandy soil are common poor soils in tunnel and foundation treatments. It is necessary to use superfine cement slurry grouting in the micro-cracks of soil. The different effectiveness of Portland cement slurry and superfine cement slurry in sandy soil by the laboratory grouting experiment method were presented in this paper. The grouting situations of superfine cement slurry injected into sand and sandy soil were explored. The investigated parameters were the dry density, wet density, moisture content, internal friction angle, and cohesion force. The results show that the consolidation effect of superfine cement is better than that of Portland cement due to the small size of superfine cement particles. The superfine cement can diffuse into the sand by infiltration, extrusion, and splitting. When the water–cement ratio of superfine cement slurry is less than 2:1 grouting into loose sand, the dry and wet density decrease with the increase in the water–cement ratio, while the moisture content and cohesive force gradually increase. When the water–cement ratio of superfine cement slurry is 1:1 grouting into loose sand and sandy soil, the dry density, wet density, and cohesive force of loose sand are larger than those of sandy soil. The results of the experiment may be relevant for engineering applications.

  9. 地铁深基坑工程抗突涌准幕灌浆技术研究%Study on Curtain Grouting Technology for Preventing Water Gushing in Works of Metro Deep Foundation Pit

    Institute of Scientific and Technical Information of China (English)

    郭宏宇

    2012-01-01

    杭州某地铁深基坑工程由于地连墙在圆砾层中成槽困难,使得地下连续墙(以下简称“地连墙”)插入深度减小,不能满足承压水抗突涌稳定性要求,基于此,依托该地铁深基坑实例,通过现场灌浆对比试验,确定帷幕灌浆参数,并按此参数设置帷幕灌浆,填充地连墙未隔断的圆砾层,与地连墙搭接形成封闭的阻水帷幕,解决承压水抗突涌问题。研究表明:圆砾层的孔隙度大、渗透性好,可进行灌浆处理;帷幕灌浆能够节省工期,节约造价,有效地解决圆砾层的承压水抗突涌问题。%Some difficulties occurred in trough work in the round gravel layer for metro deep foundation pit with floor- wall transition make the floor-wall insert depth reduced, therefore it can not meet the requirements on the stability under the pressure of water gushing. Based on these and by taking a metro deep fbundation pit as an instance, curtain grouting parameters are determined after the cornparison tests on the field grouting. The parameter is set to guide curtain grouting, fill the floor-wall no- separated gravel layer, and to form a closed water-blocking curtain of the floor-wall overlap to solve the problems occurred in pressure water to stop water gushing. The study shows that the satisfactory round gravel porosity and permeability help grouting treatment; and curtain grouting shortens construction duration with less cost, effectively providing gravel layers some solutions on pressure water preventing-gushing issues.

  10. Mejoramiento de cimentaciones en suelos y rocas aplicando las técnicas de grouting

    OpenAIRE

    Ampuero Cayo, Salomón Edgard; Ampuero Cayo, Salomón Edgard

    2012-01-01

    Las técnicas de inyecciones de grouting, se conocen desde el año 1802 en Francia, desde entonces se ha recopilado información y se practica esta técnica mejorando cada vez. Los diseños, procedimientos de inyección, están orientados hacia los objetivos básicos, que son el control de agua subterránea y el tratamiento de los macizos rocosos fracturados y suelos sin cohesión. La aplicación de las técnicas de grouting en rocas; reducen el flujo de agua, refuerzan las rocas y mitigan la formaci...

  11. The grout/glass performance assessment code system (GPACS) with verification and benchmarking

    International Nuclear Information System (INIS)

    Piepho, M.G.; Sutherland, W.H.; Rittmann, P.D.

    1994-12-01

    GPACS is a computer code system for calculating water flow (unsaturated or saturated), solute transport, and human doses due to the slow release of contaminants from a waste form (in particular grout or glass) through an engineered system and through a vadose zone to an aquifer, well and river. This dual-purpose document is intended to serve as a user's guide and verification/benchmark document for the Grout/Glass Performance Assessment Code system (GPACS). GPACS can be used for low-level-waste (LLW) Glass Performance Assessment and many other applications including other low-level-waste performance assessments and risk assessments. Based on all the cses presented, GPACS is adequate (verified) for calculating water flow and contaminant transport in unsaturated-zone sediments and for calculating human doses via the groundwater pathway

  12. Performance testing of blast furnace slag for immobilization of technetium in grout

    International Nuclear Information System (INIS)

    Gilliam, T.M.; Spence, R.D.; Evans-Brown, B.S.; Morgan, I.L.; Shoemaker, J.L.; Bostick, W.D.

    1988-01-01

    This paper presents preliminary results of a grout development effort to identify grout formulas that can satisfactorily sequester 99 Tc contained in an existing Portsmouth Gaseous Diffusion Plant waste. Technetium is of particular concern to the US Nuclear Regulatory Commission (NRC) because of its mobility and biological activity. The mobility of technetium results in large part from the movement of the pertechnate anion [prevalent in low-level radioactive waste (LLW)] through soil and geologic strata with little or no interaction with the surrounding matrix. Ground blast furnace slag has been shown to improve the leach resistance of cement-based waste forms, particularly in regard to technetium. This improved performance has been attributed to fewer and smaller pores in the solidified slags (versus a neat cement paste) and to the reduction of the pertechnate ion to a less soluble form. 9 refs., 2 tabs

  13. Seismic performance of a grout-repaired construction defect in a column plastic hinge

    International Nuclear Information System (INIS)

    Budek, A.

    2006-01-01

    A column built to test the use of high-strength transverse reinforcement in seismically-loaded shear-critical columns was found to have a construction defect. The column was built to be loaded in double bending and as such was expected to develop two plastic hinges, one at each end of column. In the plastic hinge region at the column top, a void was formed because the concrete could not pass through the load stub's reinforcing steel cage. This void was repaired using nonshrink grout placed in a fluid state. The column was tested after repair and performed satisfactorily. The grouted repair was able to support large plastic rotations and allowed the column to reach a high level of ductility. The only effects of the repair were slightly reduced concrete dilation and stiffness in the repaired hinge. (author)

  14. The relationship between compressive strength and flexural strength of pavement geopolymer grouting material

    Science.gov (United States)

    Zhang, L.; Han, X. X.; Ge, J.; Wang, C. H.

    2018-01-01

    To determine the relationship between compressive strength and flexural strength of pavement geopolymer grouting material, 20 groups of geopolymer grouting materials were prepared, the compressive strength and flexural strength were determined by mechanical properties test. On the basis of excluding the abnormal values through boxplot, the results show that, the compressive strength test results were normal, but there were two mild outliers in 7days flexural strength test. The compressive strength and flexural strength were linearly fitted by SPSS, six regression models were obtained by linear fitting of compressive strength and flexural strength. The linear relationship between compressive strength and flexural strength can be better expressed by the cubic curve model, and the correlation coefficient was 0.842.

  15. Fixation of waste materials in grouts: Part 3, Equation for critical flow rate

    International Nuclear Information System (INIS)

    Tallent, O.K.; McDaniel, E.W.; Spence, R.D.; Godsey, T.T.; Dodson, K.E.

    1986-12-01

    Critical flow rate data for grouts prepared from three distinctly different nuclear waste materials have been correlated. The wastes include Oak Ridge National Laboratory (ORNL) low-level waste (LLW) solution, Hanford Facility waste (HFW) solution, and cladding removal waste (CRW) slurry. Data for the three wastes have been correlated with a 0.96 coefficient of correlation by the following equation: log V/sub E/ = 0.289 + 0.707 log μ/sub E/, where V/sub E/ and μ/sub E/ denote critical flow rate in m 3 /min and apparent viscosity in Pa.s, respectively. The equation may be used to estimate critical flow rate for grouts prepared within the compositional range of the investigation. 5 refs., 4 figs., 7 tabs

  16. Nanocomposite hydrogels stabilized by self-assembled multivalent bisphosphonate-magnesium nanoparticles mediate sustained release of magnesium ion and promote in-situ bone regeneration.

    Science.gov (United States)

    Zhang, Kunyu; Lin, Sien; Feng, Qian; Dong, Chaoqun; Yang, Yanhua; Li, Gang; Bian, Liming

    2017-12-01

    Hydrogels are appealing biomaterials for applications in regenerative medicine due to their tunable physical and bioactive properties. Meanwhile, therapeutic metal ions, such as magnesium ion (Mg 2+ ), not only regulate the cellular behaviors but also stimulate local bone formation and healing. However, the effective delivery and tailored release of Mg 2+ remains a challenge, with few reports on hydrogels being used for Mg 2+ delivery. Bisphosphonate exhibits a variety of specific bioactivities and excellent binding affinity to multivalent cations such as Mg 2+ . Herein, we describe a nanocomposite hydrogel based on hyaluronic acid and self-assembled bisphosphonate-magnesium (BP-Mg) nanoparticles. These nanoparticles bearing acrylate groups on the surface not only function as effective multivalent crosslinkers to strengthen the hydrogel network structure, but also promote the mineralization of hydrogels and mediate sustained release of Mg 2+ . The released Mg 2+ ions facilitate stem cell adhesion and spreading on the hydrogel substrates in the absence of cell adhesion ligands, and promote osteogenesis of the seeded hMSCs in vitro. Furthermore, the acellular porous hydrogels alone can support in situ bone regeneration without using exogenous cells and inductive agents, thereby greatly simplifying the approaches of bone regeneration therapy. In this study, we developed a novel bioactive nanocomposite hydrogel based on hyaluronic acid and self-assembled bisphosphonate-magnesium (BP-Mg) nanoparticles. Such hydrogels are stabilized by the multivalent crosslinking domains formed by the aggregation of Ac-BP-Mg NPs, and therefore show enhanced mechanical properties, improved capacity for mineralization, and controlled release kinetics of Mg 2+ . Moreover, the released Mg 2+ can enhance cell adhesion and spreading, and further promote the osteogenic differentiation of hMSCs. Owing to these unique properties, these acellular hydrogels alone can well facilitate the in vivo