WorldWideScience

Sample records for sheet pile barrier

  1. Settlement during vibratory sheet piling

    NARCIS (Netherlands)

    Meijers, P.

    2007-01-01

    During vibratory sheet piling quite often the soil near the sheet pile wall will settle. In many cases this is not a problem. For situations with houses, pipelines, roads or railroads at relative short distance these settlements may not be acceptable. The purpose of the research described in this

  2. Optimal Design of Sheet Pile Wall Embedded in Clay

    Science.gov (United States)

    Das, Manas Ranjan; Das, Sarat Kumar

    2015-09-01

    Sheet pile wall is a type of flexible earth retaining structure used in waterfront offshore structures, river protection work and temporary supports in foundations and excavations. Economy is an essential part of a good engineering design and needs to be considered explicitly in obtaining an optimum section. By considering appropriate embedment depth and sheet pile section it may be possible to achieve better economy. This paper describes optimum design of both cantilever and anchored sheet pile wall penetrating clay using a simple optimization tool Microsoft Excel ® Solver. The detail methodology and its application with examples are presented for cantilever and anchored sheet piles. The effects of soil properties, depth of penetration and variation of ground water table on the optimum design are also discussed. Such a study will help professional while designing the sheet pile wall penetrating clay.

  3. Sealable joint steel sheet piling for groundwater control and remediation: Case histories

    International Nuclear Information System (INIS)

    Smyth, D.; Jowett, R.; Gamble, M.

    1997-01-01

    The Waterloo Barrier trademark steel sheet piling (patents pending) incorporates a cavity at each interlocking joint that is flushed clean and injected with sealant after the piles have been driven into the ground to form a vertical cutoff wall. The installation and sealing procedures allow for a high degree of quality assurance and control. Bulk wall hydraulic conductivities of 10 -8 to 10 -10 cm/sec have been demonstrated at field installations. Recent case histories are presented in which Waterloo Barrier trademark cutoff walls are used to prevent off-site migration of contaminated groundwater or soil gases to adjacent property and waterways. Full enclosures to isolate DNAPL source zones or portions of contaminated aquifers for pilot-scale remediation testing will also be described. Monitoring data will be used to demonstrate the effectiveness of the Waterloo Barrier trademark in these applications

  4. Bracing system of the reflecting sheets making up an insulating pile

    International Nuclear Information System (INIS)

    Carr, R.W.

    1976-01-01

    In order to reduce heat and radiation losses, the body of nuclear reactors and the connected pipe work are encased in reflecting and insulating piles of thin spaced sheets of aluminium or stainless steel. These spaced sheets are then encased in thicker and more solid internal and external shells. The piles and shells are generally shaped to follow the contour of the reactor and connected piping. It is therefore necessary to have available a study bracing system to keep the pile intact during the various handling and assembly operations. The fastening system must also exert an effect on the edge of the pile to prevent the sheets making it up from shifting in relation to each other. The description is given of a fastening system that includes an oblong section to be fitted along the edges of the piles up sheets; bracing substantially perpendicular to the oblong section, to space the sheets of the stack in pairs; and a maintaining system, normally perpendicular to the oblong section, to enable the fastener to be clipped to the edge of the sheets by bending it around the edge of each sheet of the pile [fr

  5. ENVIRONMENTAL AND ECONOMIC PROSPECTS FOR USAGE OF PULTRUDED COMPOSITE SHEET PILES

    Directory of Open Access Journals (Sweden)

    BURYA Alexander I.

    2016-11-01

    Full Text Available The article focuses on the description of pultruded composite sheet piles. The article covers the production technology, advantages over other traditional materials, as well as environmental and economic prospects for expanding of the usage of composite sheet piling.

  6. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  7. Load Test in Sheet Pile

    OpenAIRE

    Luis Orlando Ibanez

    2016-01-01

    In this work, are discussed experiences in the use of mathematical modeling and testing in hydraulic engineering structures. For this purpose the results of load tests in sheet pile, evaluating horizontal and vertical deformations that occur in the same exposed. Comparisons between theoretical methods for calculating deformations and mathematical models based on the Finite Element Method are established. Finally, the coincidence between the numerical model and the results of the load test ful...

  8. Full size testing of sheet pile walls

    NARCIS (Netherlands)

    Kuilen, J.W.G. van de; Linden, M.L.R. van der; Katsma, H.; Stolle, P.

    1996-01-01

    Azobé (Lophira alata) is widely used in timber sheet pile walls in the Netherlands. The boards in these walls are coupled and therefore load-sharing can be expected. A simulation model based on the finite element method DIANA (DIANA, 1992) was developed and load-sharing could be calculated. To check

  9. Steel Sheet Piles - Applications and Elementary Design Issues

    Science.gov (United States)

    Sobala, Dariusz; Rybak, Jarosław

    2017-10-01

    High-intensity housing having been carried out in town’s centres causes that many complex issues related to earthworks and foundations must be resolved. Project owners are required to ensure respective number of parking bays, which in turn demands 2-3 storeys of underground car parks. It is especially difficult to fulfil in dense buildings of old town areas where apart from engineering problems, very stringent requirements of heritage conservator supervision are also raised. The problems with ensuring stability of excavation sidewalls need to be, at the same time, dealt with analysis of foundations of neighbouring structures, and possible strengthening them at the stages of installing the excavation protection walls, progressing the excavations and constructing basement storeys. A separate problem refers to necessity of constructing underground storeys below the level of local groundwater. This requires long-term lowering of water table inside excavation while at possibly limited intervention in hydrological regime beyond the project in progress. In river valleys such “hoarding off” the excavation and cutting off groundwater leads to temporary or permanent disturbances of groundwater run-off and local swellings. Traditional way to protect vertical fault and simultaneously to cut-off groundwater inflow consists in application of steel sheet pilings. They enable to construct monolithic reinforced concrete structures of underground storeys thus ensuring both their tightness and high rigidity of foundation. Depending on situation, steel sheet pilings can be in retrieving or staying-in-place versions. This study deals with some selected aspects of engineering design and fabrication of sheet piling for deep excavations and underground parts of buildings.

  10. Influence of cantilevered sheet pile deflection on adjacent roadways.

    Science.gov (United States)

    2009-06-01

    Cantilevered sheet pile walls are often used adjacent roadways as temporary support during construction. Excess movement of these walls has led to excessive roadway distress causing additional repairs to be necessary. This study assessed the effects ...

  11. Efficiency analysis and assessment of interlocking PVC sheet piling walls

    International Nuclear Information System (INIS)

    Emam, A.A.

    2005-01-01

    The use of PVC sheet piling in marine environments offers a number of unique advantages that include weight saving, corrosion resistance and environmentally safe material. In this study, one of the widely used classical methods as well as a finite element analysis are used to analyze such sheet piling walls. The analysis focuses on the effect of some important parameters on the wall global behavior, bending moments, stresses and deflections. The parameters include wall cross-section, wall height, embedment depth, number and spacing of anchor rods, and type of soil and loading conditions. Furthermore, the effect of the shape of the wall cross-section and the location of the interlocking joints has been studied by using plane frame and arch-like models. Results indicate that the finite element modeling is an effective tool for numerical approximation of soil-structure interaction problems. The required theoretical embedment depth is nearly 30 % of the clear wall height. Also, the modulus of subgrade reaction has a minor effect on both cantilever wall and one anchor sheet-pile wall. Finally, lateral (horizontal) action shows that deep sections tend to behave like an arch under radial loading which might increase normal stresses at some critical sections

  12. Influences of plasticity on a sheet pile phased stochastic FE analysis

    NARCIS (Netherlands)

    Boer, A. de; Waarts, P.H.

    2000-01-01

    The paper deals with the stochastic analysis of the stability of a sheet pile soil structure. Most areas in the Netherlands have layered soil conditions. The decisive parameter in the nonlinear FE analysis is the behaviour of the soil. For layered soil conditions, the correct modelling of the

  13. Analysis of Dynamic Coupling Characteristics of the Slope Reinforced by Sheet Pile Wall

    Directory of Open Access Journals (Sweden)

    H. L. Qu

    2017-01-01

    Full Text Available Large deformation of slope caused by earthquake can lead to the loss of stability of slope and its retaining structures. At present, there have been some research achievements about the slope reinforcement of stabilizing piles. However, due to the complexity of the structural system, the coupling relationship between soil and pile is still not well understood. Hence it is of great necessity to study its dynamic characteristics further. In view of this, a numerical model was established by FLAC3D in this paper, and the deformation and stress nephogram of sheet pile wall in peak ground motion acceleration (PGA at 0.1 g, 0.2 g, and 0.4 g were obtained. Through the analysis, some conclusions were obtained. Firstly, based on the nephogram of motion characteristics and the positions of the slip surface and the retaining wall, the reinforced slope can be divided into 6 sections approximatively, namely, the sliding body parts of A, B, C, D, and E and the bedrock part F. Secondly, the deformation and stress distributions of slope reinforced by sheet pile wall were carefully studied. Based on the results of deformation calculation from time history analysis, the interaction force between structure and soil can be estimated by the difference of peak horizontal displacements, and the structure-soil coupling law under earthquake can be studied by this approach.

  14. Durability assessment of concrete sheet piling in the 'De Betuweroute' railway line

    NARCIS (Netherlands)

    Peelen, W.H.A.; Polder, R.B.

    2004-01-01

    Assessment of the durability of prestressed concrete sheet piles under the interference of CP gas pipeline system current, established that due to their low magnitude, these currents do not compromise the required 100-year service life of the structures. The sophisticated numerical modelling tools

  15. Investigation on the Effect of Drained Strength when Designing Sheet Pile Walls

    DEFF Research Database (Denmark)

    Iversen, Kirsten Malte; Nielsen, Benjaminn Nordahl; Augustesen, Anders Hust

    that the height, anchor force, and the maximum bending moment in the wall can be lowered significantly when the effective cohesion is increased above zero. However, as the cohesion increases, the drop in the moment levels off, which implies that the benefit obtained from investigations increasing the cohesion......Long sheet pile walls are constructed in the cities as an integrated part of deep excavations for e.g. parking lots, pumping stations, reservoirs, and cut and cover tunnels. To minimise costs, the strength of the soil needs to be determined in the best possible way. The drained strength of clay...... expressed by c and ϕ is often estimated as c 10% = 10%・cu, and found by estimations based on the soil describtion, respectively. However, due to possible slicken slides and tension cracks, c = 0 is used on the back side of the sheet pile wall. This reduces the strength significantly. A parametric study...

  16. SUITABLE LOCATION OF SHEET PILE UNDER DAM RESTING ON SANDY SOIL WITH CAVITY

    Directory of Open Access Journals (Sweden)

    Laith J. Aziz

    2018-05-01

    Full Text Available This research describes the seepage characteristics of experimental model test of dam with cutoff located at different region (at dam heel, at mid floor of dam, and at dam toe. It is resting on sandy soil with cavity at different locations in X and Y directions (such as in Al-Najaf soil city. Thirty three model tests are performed in laboratory by using steel box to estimate the quantity of the seepage and flow lines direction. It was concluded that the best location of the cutoff wall is at the dam toe for model test with cavity ( Xc B = 0 and 0.5, but for model test with cavity ( Xc B ≥1, the best location of the sheet pile wall becomes at the dam heel. For negative location of the cavity, the best location of the sheet pile wall is at the middle of the floor dam.

  17. Vertical Equilibrium of Sheet Pile Walls with Emphasis on Toe Capacity and Plugging

    DEFF Research Database (Denmark)

    Iversen, Kirsten Malte; Augustesen, Anders Hust; Nielsen, Benjaminn Nordahl

    Constructions including retaining walls are normally established in areas where it is impossible to conduct an excavation with inclined sides. Due to large excavation depths and due to restrictions on the deformations of the wall, it is often necessary to anchor the wall. The limited space makes...... at the pile toe to fulfil vertical equilibrium. The paper describes a case study of sheet pile walls in Aalborg Clay, and the amount of loads transferred as point loads at the pile toe for free and anchored walls is estimated. A parametric study is made for the free wall with regards to the height...... and the roughness of the wall. Due to limitations of the calculation method, the study of the anchored wall only includes variation of the roughness. For the case study, it is found that the vertical equilibrium is fulfilled for the considered free wall. An anchored wall needs a plug forming at the pile toe...

  18. Ground Vibration Isolation of Multiple Scattering by Using Rows of Tubular Piles as Barriers

    Directory of Open Access Journals (Sweden)

    Miao-miao Sun

    2014-01-01

    Full Text Available A new formal solution for the multiple scattering of plane harmonic waves by a group of arbitrary configuration tubular piles in an elastic total space is derived. Each order of scattering satisfies prescribed boundary conditions at the interface of tubular piles, which is delivered as the sum of incident and scattering waves. The first order performs the scattering wave by each scattered pile and the subsequent orders resulted from the excitation of each pile of first order of scattering from the remaining tubular piles. Advanced scattering orders can be regarded as the same manners. Several series of scattering coefficients are figured out with the aids of addition theorem so that the exact steady-state solution for the scattered displacement and stress is obtained. Particularly, when internal diameter of tubular piles tends to be infinitely small, it degenerates to a solid pile problem. By imposing the normalized displacement amplitudes and transmissibility indices, the influences of specific parameters such as scattering orders, internal and external diameter ratio of piles, pile material rigidity, position and distances between tubular pile and pile rows, and pile numbers are discussed. Certain recommended conclusions have been drawn as the guidelines of practical engineering design for discontinuous barrier of tubular piles.

  19. Uncertainty assessment of a dike with an anchored sheet pile wall using FEM

    Directory of Open Access Journals (Sweden)

    Rippi Aikaterini

    2016-01-01

    Full Text Available The Dutch design codes for the dikes with retaining walls rely on Finite Element Analysis (FEM in combination with partial safety factors. However, this can lead to conservative designs. For this reason, in this study, a reliability analysis is carried out with FEM calculations aiming to demonstrate the feasibility of reliability analysis for a dike with an anchored sheet pile wall modelled in the 2D FEM, Plaxis. Sensitivity and reliability analyses were carried out and enabled by coupling the uncertainty package, OpenTURNS and Plaxis. The most relevant (ultimate limit states concern the anchor, the sheet pile wall, the soil body failure (global instability and finally the system. The case was used to investigate the applicability of the First Order Reliability Method (FORM and Directional Sampling (DS to analysing these limit states. The final goal is to estimate the probability of failure and identify the most important soil properties that affect the behaviour of each component and the system as a whole. The results of this research can be used to assess and optimize the current design procedure for dikes with retaining walls.

  20. Pile-up and defective pulse rejection by pulse shape discrimination in surface barrier detectors

    International Nuclear Information System (INIS)

    Sjoeland, K.A.; Kristiansson, P.

    1994-01-01

    A technique to reject pile-up pulses and defective tail pulses from surface barrier detectors by the use of pulse shape discrimination is demonstrated. The electronic implementation of the pulse shape discrimination is based upon the zero crossing technique and for data reduction multiparameter techniques are used. The characteristic τ value for pile-up rejection is shown to be less than 56 ns. Its effect on detection limits from tail reduction in Particle Elastic Scattering Analysis (PESA) and pile-up peak suppression is discussed. ((orig.))

  1. 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

  2. Model Solutions for Performance-Based Seismic Analysis of an Anchored Sheet Pile Quay Wall

    OpenAIRE

    C. J. W. Habets; D. J. Peters; J. G. de Gijt; A. V. Metrikine; S. N. Jonkman

    2016-01-01

    Conventional seismic designs of quay walls in ports are mostly based on pseudo-static analysis. A more advanced alternative is the Performance-Based Design (PBD) method, which evaluates permanent deformations and amounts of (repairable) damage under seismic loading. The aim of this study is to investigate the suitability of this method for anchored sheet pile quay walls that were not purposely designed for seismic loads. A research methodology is developed in which pseudo-static, permanent-di...

  3. Using Frozen Barriers for Containment of Contaminants

    Science.gov (United States)

    2017-09-21

    barriers are constructed of grout slurry and plastic or steel sheet pilings. Circumferential barriers can be used to completely enclose a source of...2.1.1 Slurry walls A soil-bentonite slurry trench cutoff wall (slurry wall) is excavated and backfilled with grout, cement , or soil-bentonite...installation requires a mixing area, and there is a substantial amount of excavation and the need to dispose of spoil. The advantages of cement -based

  4. Ultimate limit state design of sheet pile walls by finite elements and nonlinear programming

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Damkilde, Lars; Krabbenhøft, Sven

    2005-01-01

    The design of sheet pile walls by lower bound limit analysis is considered. The design problem involves the determination of the necessary yield moment of the wall, the wall depth and the anchor force such that the structure is able to sustain the given loads. This problem is formulated...... as a nonlinear programming problem where the yield moment of the wall is minimized subject to equilibrium and yield conditions. The finite element discretization used enables exact fulfillment of these conditions and thus, according to the lower bound theorem, the solutions are safe....

  5. Mitigation of Traffic-Induced Ground Vibration by Inclined Wave Barriers

    DEFF Research Database (Denmark)

    Andersen, Lars; Augustesen, Anders Hust

    2009-01-01

    Double sheet pile walls can be used as wave barriers in order to mitigate ground vibrations from railways. The present analysis concerns the efficiency of such barriers, especially with regard to the influence of the barrier inclination and the backfill between the walls. Thus, the screening capa...... of reference following the load. This allows a computation of the steady state response to a harmonically varying point source moving at different speeds typical for a train....

  6. Practical Application of Sheet Lead for Sound Barriers.

    Science.gov (United States)

    Lead Industries Association, New York, NY.

    Techniques for improving sound barriers through the use of lead sheeting are described. To achieve an ideal sound barrier a material should consist of the following properties--(1) high density, (2) freedom from stiffness, (3) good damping capacity, and (4) integrity as a non-permeable membrane. Lead combines these desired properties to a greater…

  7. Radon barrier field-test monitoring at Grand Junction tailings pile

    International Nuclear Information System (INIS)

    Freeman, H.D.; Hartley, J.N.; Gee, G.W.

    1983-11-01

    Pacific Northwest Laboratory (PNL), as part of the Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) technology development program, has conducted three large-scale field tests of radon covers at the uranium mill tailings pile in Grand Junction, Colorado. The barrier systems, monitored for radon flux for over two years, include earthen, multilayer, and asphalt emulsion covers. Results of the monitoring have shown that a variety of cover systems can meet the Environmental Protection Agency (EPA) standard. The most effective covers tested were asphalt emulsion and earthen (mancos shale). 10 references, 7 figures, 1 table

  8. Bending Moment Calculations for Piles Based on the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Yu-xin Jie

    2013-01-01

    Full Text Available Using the finite element analysis program ABAQUS, a series of calculations on a cantilever beam, pile, and sheet pile wall were made to investigate the bending moment computational methods. The analyses demonstrated that the shear locking is not significant for the passive pile embedded in soil. Therefore, higher-order elements are not always necessary in the computation. The number of grids across the pile section is important for bending moment calculated with stress and less significant for that calculated with displacement. Although computing bending moment with displacement requires fewer grid numbers across the pile section, it sometimes results in variation of the results. For displacement calculation, a pile row can be suitably represented by an equivalent sheet pile wall, whereas the resulting bending moments may be different. Calculated results of bending moment may differ greatly with different grid partitions and computational methods. Therefore, a comparison of results is necessary when performing the analysis.

  9. Rational use of anchor pile material of the thin retaining walls

    Directory of Open Access Journals (Sweden)

    Yushkov Boris Semenovich

    2014-12-01

    Full Text Available The article considers the urgency of application of the reinforced concrete anchor piles in the constructions of retaining structures associated with the possibility of establishing rigid joint of element interface and more durable pile constructions in the soil. The features of the inclined anchor piles work as a part of sheet-pile retaining walls are noted. There was performed a study of the stress-strain state of the inclined reinforced concrete anchor piles of the thin sheet-pile wall with the reinforced concrete face members of T-section, combined with piles by a longitudinal beam. The authors consider a constructive scheme of retaining structure and list the applied loads. The efforts in the anchor piles were determined. The bending-moment curves show the character of the force distribution along the pile. A form of the pile ensuring the rational distribution of material along the pile is presented. The distribution of efforts along the length and effect of filling on its operation in the soil were accepted as the criteria of construction solution for a pile. The substantiation of the proposed design of pile is presented in terms of its stress-strain state and the rational use of material. The authors made conclusions on the reasonability of adopted design solutions associated with an increase in the flexural strength of pile, increment of the ultimate pullout capacity, stability improvement, effective use of backfill and exception of the «out of operation» areas of the pile.

  10. Ultimate Limit State Design Of Sheet Pile Walls By Finite Elements And Nonlinear Programming

    DEFF Research Database (Denmark)

    Krabbenhøft, Kristian; Damkilde, Lars; Krabbenhøft, Sven

    2002-01-01

    Limit analysis has been used for decades in civil and mechanical engineering practice as a means of analyzing structures of materials which with reasonable accuracy can be described as being rigid-perfectly plastic. Such materials include steel, concrete and soils. Traditionally, most attention has...... been given to the problem which consists of determining the ultimate magnitude of a given set of loads acting on a structure with a given geometry. This problem is relevant when determining e.g. the necessary extrusion pressure in metal forming problems, when evaluating the bearing capacity...... is the load intensity. In the paper we consider the latter of these problems with particular reference to the design of sheet pile walls....

  11. Field Tests to Investigate the Penetration Rate of Piles Driven by Vibratory Installation

    Directory of Open Access Journals (Sweden)

    Zhaohui Qin

    2017-01-01

    Full Text Available Factors directly affecting the penetration rate of piles installed by vibratory driving technique are summarized and classified into seven aspects which are driving force, resistance, vibratory amplitude, energy consumption, speeding up at the beginning, pile plumbness keeping, and slowing down at the end, from the mechanism and engineering practice of the vibratory pile driving. In order to find out how these factors affect the penetration rate of the pile in three major actors of vibratory pile driving: (i the pile to be driven, (ii the selected driving system, and (iii the imposed soil conditions, field tests on steel sheet piles driven by vibratory driving technique in different soil conditions are conducted. The penetration rates of three different sheet pile types having up to four different lengths installed using two different vibratory driving systems are documented. Piles with different lengths and types driven with or without clutch have different penetration rates. The working parameters of vibratory hammer, such as driving force and vibratory amplitude, have great influences on the penetration rate of the pile, especially at the later stages of the sinking process. Penetration rate of piles driven in different soil conditions is uniform because of the different penetration resistance including shaft friction and toe resistance.

  12. 1981 radon barrier field test at Grand Junction uranium mill tailings pile

    International Nuclear Information System (INIS)

    Hartley, J.N.; Gee, G.W.; Baker, E.G.; Freeman, H.D.

    1983-04-01

    Technologies to reduce radon released from uranium mill tailings are being investigated by Pacific Northwest Laboratory as part of the Department of Energy's Uranium Mill Tailings Remedial Action Project (UMTRAP) Technology development program. These technologies include: (1) earthen cover systems, (2) multilayer cover systems, and (3) asphalt emulsion radon barrier systems. During the summer of 1981, a field test was initiated at the Grand Junction, Colorado, uranium tailings pile to evaluate and compare the effectiveness of each radon barrier system. Test plots cover about 1.2 ha (3 acres). The field test has demonstrated the effectiveness of all three cover systems in reducing radon release to near background levels ( 2 s - 1 ). In conjunction with the field tests, column tests (1.8 m diameter) were initiated with cover systems similar to those in the larger field test plots. The column tests allow a direct comparison of the two test procedures and also provide detailed information on radon transport

  13. Aerial sampling of emissions from biomass pile burns in ...

    Science.gov (United States)

    Emissions from burning piles of post-harvest timber slash in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matter (PM2.5 µm), black carbon, ultraviolet absorbing PM, elemental/organic carbon, semi-volatile organics (polycyclic aromatic hydrocarbons and polychlorinated dibenzodioxins/dibenzofurans), filter-based metals, and volatile organics were sampled for determination of emission factors. The effect on emissions from covering or not covering piles with polyethylene sheets to prevent fuel wetting was determined. Results showed that the uncovered (“wet”) piles burned with lower combustion efficiency and higher emissions of volatile organic compounds. Results for other pollutants will also be discussed. This work determined the emissions from open burning of forest slash wood, with and without plastic sheeting. The foresters advocate the use of plastic to keep the slash wood dry and aid in the controlled combustion of the slash to reduce fuel loading. Concerns about the emissions from the burning plastic prompted this work which conducted an extensive characterization of dry, wet, and dry with plastic slash pile emissions.

  14. Spin-inversion in nanoscale graphene sheets with a Rashba spin-orbit barrier

    Directory of Open Access Journals (Sweden)

    Somaieh Ahmadi

    2012-03-01

    Full Text Available Spin-inversion properties of an electron in nanoscale graphene sheets with a Rashba spin-orbit barrier is studied using transfer matrix method. It is found that for proper values of Rashba spin-orbit strength, perfect spin-inversion can occur in a wide range of electron incident angle near the normal incident. In this case, the graphene sheet with Rashba spin-orbit barrier can be considered as an electron spin-inverter. The efficiency of spin-inverter can increase up to a very high value by increasing the length of Rashba spin-orbit barrier. The effect of intrinsic spin-orbit interaction on electron spin inversion is then studied. It is shown that the efficiency of spin-inverter decreases slightly in the presence of intrinsic spin-orbit interaction. The present study can be used to design graphene-based spintronic devices.

  15. APPLICATION OF STEEL PIPE PILE LOADING TESTS TO DESIGN VERIFICATION OF FOUNDATION OF THE TOKYO GATE BRIDGE

    Science.gov (United States)

    Saitou, Yutaka; Kikuchi, Yoshiaki; Kusakabe, Osamu; Kiyomiya, Osamu; Yoneyama, Haruo; Kawakami, Taiji

    Steel sheet pipe pile foundations with large diameter steel pipe sheet pile were used for the foundation of the main pier of the Tokyo Gateway bridge. However, as for the large diameter steel pipe pile, the bearing mechanism including a pile tip plugging effect is still unclear due to lack of the practical examinations even though loading tests are performed on Trans-Tokyo Bay Highway. In the light of the foregoing problems, static pile loading tests both vertical and horizontal directions, a dynamic loading test, and cone penetration tests we re conducted for determining proper design parameters of the ground for the foundations. Design parameters were determined rationally based on the tests results. Rational design verification was obtained from this research.

  16. Timber Piling Barrier and Chemical Preservation Annual Costs Comparison.

    Science.gov (United States)

    1987-06-01

    has such an informative collection of pertinent records. The estimated useful life of PVC wrapped piling has been increasing yearly with the continued...by the more than 25 tons of floating debris that is collected from the harbor daily, there has been no failure of a wrapped pile. The relative...8217I Nuk \\% pns Sck OMu ’,iol ’L I t OS-IAS 14 ilu"M odk 41~IS I’cad l II-o Ill 0 OS-*IN-SN HI 51-4 )H it l uk s. %ctt O rl-un..I5 uk 2 ti I ()MNASSt

  17. Shear flow generation and transport barrier formation on rational surface current sheets in tokamaks

    International Nuclear Information System (INIS)

    Wang Xiaogang; Xiao Chijie; Wang Jiaqi

    2009-01-01

    Full text: A thin current sheet with a magnetic field component in the same direction can form the electrical field perpendicularly pointing to the sheet, therefore an ExB flow with a strong shear across the current sheet. An electrical potential well is also found on the rational surface of RFP as well as the neutral sheet of the magnetotail with the E-field pointing to the rational (neutral) surface. Theoretically, a current singularity is found to be formed on the rational surface in ideal MHD. It is then very likely that the sheet current on the rational surfaces will generate the electrical potential well in its vicinity so the electrical field pointing to the sheet. It results in an ExB flow with a strong shear in the immediate neighborhood of the rational surface. It may be the cause of the transport barrier often seen near the low (m, n) rational surfaces with MHD signals. (author)

  18. Value engineering study for seletion of verticle barrier technology at a Superfund site

    International Nuclear Information System (INIS)

    Bryan, E.E.; Guglielmetti, J.L.; Butler, P.B.; Brill, M.P.

    1997-01-01

    A value engineering (VE) study was conducted to identify and evaluate vertical barrier technologies and alignments for a Superfund project in New Castle County, Delaware. The objective was to select and recommend the most appropriate vertical barrier(s) for two separate landfills and a portion of the manufacturing plant on the site. A VE team was assembled to identify and evaluate site specific issues related to effectiveness, constructability and cost for numerous vertical barrier technologies. Several cost-effective alternatives were identified that met project objectives. The VE study concluded that a composite vertical barrier system consisting of a soil-bentonite slurry trench and steel sheet piles would provide effective containment of the North Landfill. Additionally, the geologic confining unit specified in the Record of Decision (ROD) was found to be unsuitable as a vertical barrier key and a more suitable, shallow confining unit was discovered. This paper describes the value engineering process and results of the VE study for one of the landfills

  19. Big Pile or Small Pile?

    Science.gov (United States)

    Branca, Mario; Quidacciolu, Rossana G.; Soletta, Isabella

    2013-01-01

    The construction of a voltaic pile (battery) is a simple laboratory activity that commemorates the invention of this important device and is of great help in teaching physics. The voltaic pile is often seen as a scientific toy, with the "pile" being constructed from fruit. These toys use some strips of copper and zinc inserted in a piece…

  20. Moisture content in raw rubber sheet analyzed by transflectance near infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Ronnarit Rittiron

    2014-07-01

    Full Text Available Moisture content is an important trait for rubber sheet trading system. Therefore, a calibration equation for predicting moisture content was created by near infrared (NIR technique in order to develop a more fair trading system in Thailand. Spectra were recorded in two systems. One was measurement on each rubber sheet and the other was on a pile of sheets. Both were measured by a handheld NIR spectrometer in the short wavelength region (700–1100 nm in the transflectance mode using Teflon as a diffuse reflector. The spectra showed the peak at about 900 nm which belongs to isoprene, the major component of rubber sheet. Pretreatment with second derivative was applied to remove baseline shift effect occurring due to thickness differences on each rubber sheet. From validation results, moisture contents predicted by single sheet system were more accurate than a pile of sheet system with standard error of prediction (SEP = 0.39% and bias of -0.07%, and they were not significantly different from the actual values at 95% confidence. As a result, determining moisture content in each rubber sheet by a handheld NIR spectrometer provided accurate values, easy and rapid operation.

  1. Swimming-pool piles; Piles piscines

    Energy Technology Data Exchange (ETDEWEB)

    Trioulaire, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10{sup 13}. This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [French] En France, deux piles piscines, Melusine et Triton, viennent d'entrer en service. La pile piscine est l'outil de recherche ideal pour des flux de neutrons de l'ordre de 10{sup 13}. Ce type de pile peut interesser des maintenant de nombreux centres de recherches mais il faut reduire son prix de revient et rompre avec le conformisme de sa conception. Il y a avantage: - a enterrer la piscine; - a supprimer les canaux experimentaux; - a concentrer le circuit de refrigeration dans la piscine; - a effectuer toutes les manipulations dans l'eau; - a doubler le coeur. (auteur)

  2. Thermal conductivity of sintered UO{sub 2} under in-pile conditions; Conductibilite thermique de l'UO{sub 2} fritte dans les conditions d'utilisation en pile

    Energy Technology Data Exchange (ETDEWEB)

    Stora, J P; Bernardy De Sigoyer, B; Delmas, R; Deschamps, P; Lavaud, B; Ringot, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    The temperature distribution in a stack of sintered UO{sub 2} cylinders has been studied both in the laboratory where the heat energy is produced by an axial heating element, and in-pile, where the heating is due solely to nuclear effects. Under a high thermal gradient the UO{sub 2} cracks both along radial planes and along pseudo-cylindrical surfaces: these latter act as thermal barriers to the heat flow, It is therefore an apparent thermal conductivity k{sub a}(T), lower than the intrinsic value k(T) of this parameter which is measured. The efficiency of these barriers decreases when the gap decreases and when the external pressure acting on the cracked stack increases: in the limiting case, for high values of the binding strain, k{sub a}(T) {approx_equal} k(T). In the domain of phonon conduction (T {<=} 1350 deg C), the expression kw.cm{sup -1}.C{sup -1}=1/(11+0.024*T) accounts for the real thermal conductivity. Above 1350 deg C the thermal conductivity increases. Two in-pile measurements up to 1250 deg C carried out using cartridges fitted with thermocouples confirm, within the limits of experimental error, the above expression and the qualitative effects of the binding strains. Similar tests have been carried out-of-pile and in-pile on the real shape of the EL-4 fuel 'pencils'. Out-of-pile, the influence of the initial free gap, of the nature of the gas filing the 'pencil' and of the external pressure have been studied; the results are compatible with the above interpretation; It appears that an external pressure of 60 kg/cm{sup 2} is insufficient to restore completely the thermal conductivity of the fuel. (authors) [French] La distribution de temperature dans un empilement de cylindres d'UO{sub 2} fritte est etudiee a la fois au laboratoire, ou l'energie calorifique est produite par un element chauffant axial, et en pile, ou l'echauffement est uniquement nucleaire. Sous gradient thermique eleve, l'UO{sub 2} se fracture a la fois suivant des plans radiaux et

  3. The pile EL3; Pile EL3

    Energy Technology Data Exchange (ETDEWEB)

    Robert, J.; Raievski, V. [Commissariat a l' Energie Atomique, Paris (France). Centre d' Etudes Nucleaires; Hainzelin, J. [Chantiers de l' Atlantique (Penhoet-Loire), 75 - Paris (France)

    1959-07-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10{sup 14} n/cm{sup 2}/s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [French] Le programme de la pile laboratoire a haut flux EL3, a ete fixe en octobre 1954. C'est une pile moderee et refroidie a l'eau lourde. Les barres de combustible sont en uranium metal a 1,6 pour cent - 2 pour cent de molybdene, gainees a l'aluminium. Le flux thermique maximum dans le moderateur est de 10{sup 14} n/cm{sup 2}/s. Les etudes ont commence en janvier 1955, la construction en mai 1955, la premiere divergence a eu lieu en juillet 1957. On trouvera dans ce rapport, une description generale de la pile et de ses batiments annexes, l'etude physique de la pile et un certain nombre d'etudes technologiques executees pour la construction d'EL3. (auteur)

  4. The pile EL3; Pile EL3

    Energy Technology Data Exchange (ETDEWEB)

    Robert, J; Raievski, V [Commissariat a l' Energie Atomique, Paris (France). Centre d' Etudes Nucleaires; Hainzelin, J [Chantiers de l' Atlantique (Penhoet-Loire), 75 - Paris (France)

    1959-07-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10{sup 14} n/cm{sup 2}/s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [French] Le programme de la pile laboratoire a haut flux EL3, a ete fixe en octobre 1954. C'est une pile moderee et refroidie a l'eau lourde. Les barres de combustible sont en uranium metal a 1,6 pour cent - 2 pour cent de molybdene, gainees a l'aluminium. Le flux thermique maximum dans le moderateur est de 10{sup 14} n/cm{sup 2}/s. Les etudes ont commence en janvier 1955, la construction en mai 1955, la premiere divergence a eu lieu en juillet 1957. On trouvera dans ce rapport, une description generale de la pile et de ses batiments annexes, l'etude physique de la pile et un certain nombre d'etudes technologiques executees pour la construction d'EL3. (auteur)

  5. 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.

  6. DRIVEN POLYSTRONG REINFORCED CONCRETE PILES AND NEW DESIGN OF PILE CAPS

    Directory of Open Access Journals (Sweden)

    I. I. Bekbasarov

    2015-01-01

    Full Text Available The paper presents constructional and technological features for manufacturing driven piles with variable strength of pile shaft. Economical efficiency of their production has been shown in the paper. The paper provides a pile cap design that ensures perception of hammer impacts with the help of lateral edges of the pile cap. Driven reinforced concrete piles which are manufactured from three shaft sections having various strength have been proposed in the paper. Material strength (concrete grade and diameter of bars and length of shaft sections are given on a case by case basis in accordance with nature and rate of stresses in piles during their driving process. Manufacturing of polystrong piles provides an opportunity to select them for a particular construction site with due account of their preservation during driving process.A pile cap has been developed that as opposed to existing analogous designs makes it possible to transmit impact efforts from a hammer to the pile through lateral surface of its head part. The pile cap provides the possibility to increase an area for perception of hammer impact efforts by the pile and in doing so it is possible significantly to reduce a damage risk and destruction of pile concrete during its driving. Application of polystrong piles and their driving with the help of new pile cap are considered as a basis for defect-free and resource-saving technology for pile foundations in the construction.

  7. Thermal conductivity of sintered UO2 under in-pile conditions

    International Nuclear Information System (INIS)

    Stora, J.P.; Bernardy De Sigoyer, B.; Delmas, R.; Deschamps, P.; Lavaud, B.; Ringot, C.

    1964-01-01

    The temperature distribution in a stack of sintered UO 2 cylinders has been studied both in the laboratory where the heat energy is produced by an axial heating element, and in-pile, where the heating is due solely to nuclear effects. Under a high thermal gradient the UO 2 cracks both along radial planes and along pseudo-cylindrical surfaces: these latter act as thermal barriers to the heat flow, It is therefore an apparent thermal conductivity k a (T), lower than the intrinsic value k(T) of this parameter which is measured. The efficiency of these barriers decreases when the gap decreases and when the external pressure acting on the cracked stack increases: in the limiting case, for high values of the binding strain, k a (T) ≅ k(T). In the domain of phonon conduction (T ≤ 1350 deg C), the expression kw.cm -1 .C -1 =1/(11+0.024*T) accounts for the real thermal conductivity. Above 1350 deg C the thermal conductivity increases. Two in-pile measurements up to 1250 deg C carried out using cartridges fitted with thermocouples confirm, within the limits of experimental error, the above expression and the qualitative effects of the binding strains. Similar tests have been carried out-of-pile and in-pile on the real shape of the EL-4 fuel 'pencils'. Out-of-pile, the influence of the initial free gap, of the nature of the gas filing the 'pencil' and of the external pressure have been studied; the results are compatible with the above interpretation; It appears that an external pressure of 60 kg/cm 2 is insufficient to restore completely the thermal conductivity of the fuel. (authors) [fr

  8. Taming Windscale's piles

    International Nuclear Information System (INIS)

    Adams, A.L.

    1989-01-01

    The options as to what to do with the Windscale Piles are being assessed before a final decision on decommissioning is made. Both Piles were shutdown in 1957 following the fire in the Pile number 1. Pile 1 still contains 22 tons of natural uranium fuel. The details of graphite moderator content, biological shielding and other components and containment are given. The fuel and isotope channels in Pile 2 have been examined and the air and water ducts have been inspected. The chimneys of both Piles are contaminated and all entrances have been sealed. Before any work starts the air outlet ducts will be sealed from the chimney and a ventilation system installed. A manipulator is being prepared to remove the remaining fuel elements from both Piles. The proposed decommissioning programme for both Piles is outlined. (U.K.)

  9. Frozen Soil Barrier. Subsurface Contaminants Focus Area. OST Reference No. 51

    International Nuclear Information System (INIS)

    1999-01-01

    Problem: Hazardous and radioactive materials have historically been disposed of at the surface during operations at Department of Energy facilities. These contaminants have entered the subsurface, contaminating soils and groundwater resources. Remediation of these groundwater plumes using the baseline technology of pump and treat is expensive and takes a long time to complete. Containment of these groundwater plumes can be alternative or an addition to the remediation activities. Standard containment technologies include slurry walls, sheet piling, and grouting. These are permanent structures that once installed are difficult to remove. How It Works: Frozen Soil Barrier technology provides a containment alternative, with the key difference being that the barrier can be easily removed after a period of time, such as after the remediation or removal of the source is completed. Frozen Soil Barrier technology can be used to isolate and control the migration of underground radioactive or other hazardous contaminants subject to transport by groundwater flow. Frozen Soil Barrier technology consists of a series of subsurface heat transfer devices, known as thermoprobes, which are installed around a contaminant source and function to freeze the soil pore water. The barrier can easily be maintained in place until remediation or removal of the contaminants is complete, at which time the barrier is allowed to thaw.

  10. Pile Driving

    Science.gov (United States)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  11. Seismic response of pile foundations and pile forces caused by kinematic and inertial interaction

    International Nuclear Information System (INIS)

    Hartmann, H.G.; Waas, G.

    1985-01-01

    The horizontal motion and pile forces of pile groups subjected to earthquake excitation are analysed. The piles are modelled as linear elastic beam elements embedded in a layered linear visco-elastic soil medium. Pile-soil-pile interaction is included. The earthquake excitation results from vertically propagating shear waves. Kinematic and inertial interaction effects on foundation motion and pile forces are studied for a single pile, a small pile group and a large pile group. Soft and stiff soil conditions are considered, and the effect of a flexible vs. a rigid halfspace below the soil layers is shown. (orig.)

  12. Pile load test on large diameter steel pipe piles in Timan-Pechora, Russia

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, S. [Golder Associates Inc., Houston, TX (United States); Tart, B. [Golder Associates Inc., Anchorage, AK (United States); Swartz, R. [Paragon Engineering Services Inc., Houston, TX (United States)

    1994-12-31

    Pile load testing conducted in May and June of 1993 at the Polar Lights Ardalin project in Arkangelsk province, Russia, was documented. Pile load testing was conducted to determine the ultimate and allowable pile loads for varying pile lengths and ground temperature conditions and to provide creep test data for deformation under constant load. The piles consisted of 20 inch diameter steel pipe piles driven open ended through prebored holes into the permafrost soils. Ultimate pile capacities, adfreeze bond, and creep properties observed were discussed. 10 figs., 4 tabs.

  13. Piles of objects

    KAUST Repository

    Hsu, Shu-Wei

    2010-01-01

    We present a method for directly modeling piles of objects in multi-body simulations. Piles of objects represent some of the more interesting, but also most time-consuming portion of simulation. We propose a method for reducing computation in many of these situations by explicitly modeling the piles that the objects may form into. By modeling pile behavior rather than the behavior of all individual objects, we can achieve realistic results in less time, and without directly modeling the frictional component that leads to desired pile shapes. Our method is simple to implement and can be easily integrated with existing rigid body simulations. We observe notable speedups in several rigid body examples, and generate a wider variety of piled structures than possible with strict impulse-based simulation. © 2010 ACM.

  14. Monitoring dc stray current corrosion at sheet pile structures

    NARCIS (Netherlands)

    Peelen, W.H.A.; Neeft, E.A.C.; Leegwater, G.; Kanten-Roos, W. van; Courage, W.M.G.

    2012-01-01

    Steel is discarded by railway owners as a material for underground structures near railway lines, due to uncertainty over increased corrosion by DC stray currents stemming from the traction power system. This paper presents a large scale field test in which stray currents interference of a sheet

  15. Underwater noise reduction of marine pile driving using a double pile.

    Science.gov (United States)

    2015-12-01

    Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. : It has been shown that current pile driving noise attenuation techniques, such as bubble curtains and : cofferdams, provide limited noise r...

  16. Static pile load tests on driven piles into Intermediate-Geo Materials.

    Science.gov (United States)

    2016-09-01

    The Wisconsin Department of Transportation (WisDOT) has concerns with both predicting pile lengths and pile capacities for H-piles driven into Intermediate-Geo Materials (IGM). The goal of the research was to perform 7 static axial load tests at 7 lo...

  17. Pile Driving Analysis for Pile Design and Quality Assurance

    Science.gov (United States)

    2017-08-01

    Driven piles are commonly used in foundation engineering. The most accurate measurement of pile capacity is achieved from measurements made during static load tests. Static load tests, however, may be too expensive for certain projects. In these case...

  18. Windscale pile core surveys

    International Nuclear Information System (INIS)

    Curtis, R.F.; Mathews, R.F.

    1996-01-01

    The two Windscale Piles were closed down, defueled as far as possible and mothballed for thirty years following a fire in the core of Pile 1 in 1957 resulting from the spontaneous release of stored Wigner energy in the graphite moderator. Decommissioning of the reactors commenced in 1987 and has reached the stage where the condition of both cores needs to be determined. To this end, non-intrusive and intrusive surveys and sampling of the cores have been planned and partly implemented. The objectives for each Pile differ slightly. The location and quantity of fuel remaining in the damaged core of Pile 1 needed to be established, whereas the removal of all fuel from Pile 2 needed to be confirmed. In Pile 1, the possible existence of a void in the core is to be explored and in Pile 2, the level of Wigner energy remaining required to be quantified. Levels of radioactivity in both cores needed to be measured. The planning of the surveys is described including strategy, design, safety case preparation and the remote handling and viewing equipment required to carry out the inspection, sampling and monitoring work. The results from the completed non-intrusive survey of Pile 2 are summarised. They confirm that the core is empty and the graphite is in good condition. The survey of Pile 1 has just started. (UK)

  19. Soil heating during burning of forest slash piles and wood piles

    Science.gov (United States)

    Matt D. Busse; Carol J. Shestak; Ken R. Hubbert

    2013-01-01

    Pile burning of conifer slash is a common fuel reduction practice in forests of the western United States that has a direct, yet poorly quantified effect on soil heating. To address this knowledge gap, we measured the heat pulse beneath hand-built piles ranging widely in fuel composition and pile size in sandy-textured soils of the Lake Tahoe Basin. The soil heat pulse...

  20. Use of geothermal piles combined with pile foundations

    Directory of Open Access Journals (Sweden)

    Ivan Kuzytskyi

    2016-07-01

    Full Text Available The possibility of use of geothermal piles in conditions of cold climate is considered. Full-scale experiment is conducted for using this technology in Kiev. Obtained results testify about a possibility for using the system in conditions of Ukraine, but this technology requires more detailed study and simulation of multiannual cycle of use of geothermal piles 

  1. Safety precautions in atomic pile control (1962); Securite dans le controle des piles atomiques (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author) [French] Nous avons aborde le probleme de la securite dans le controle des piles atomiques a la suite de notre participation d'une part aux avant rojets de piles atomiques du CE.A. et d'autre part a l'examen au sein de la sous ommission de surete des piles, de la securite des piles du CE.A. en fonctionnement ou en projet. Nous avons ete amenes a nous interesser alors aux risques encourus par les piles pendant leur fonctionnement et par la meme a leur comportement en regime dynamique. Ce travail traite principalement de l'importance des securites intrinseques, de l'influence des variations de reactivite sur les evolutions de puissance en regime d'accident et du developpement d'appareillages de securite robustes et de fonctionnement tres sur. L'accident de demarrage a ete particulierement developpe aussi bien pour les piles a bas

  2. Safety precautions in atomic pile control (1962); Securite dans le controle des piles atomiques (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author) [French] Nous avons aborde le probleme de la securite dans le controle des piles atomiques a la suite de notre participation d'une part aux avant rojets de piles atomiques du CE.A. et d'autre part a l'examen au sein de la sous ommission de surete des piles, de la securite des piles du CE.A. en fonctionnement ou en projet. Nous avons ete amenes a nous interesser alors aux risques encourus par les piles pendant leur fonctionnement et par la meme a leur comportement en regime dynamique. Ce travail traite principalement de l'importance des securites intrinseques, de l'influence des variations de reactivite sur les evolutions de puissance en regime d'accident et du developpement d'appareillages de securite robustes et de fonctionnement tres sur. L'accident de demarrage a ete particulierement

  3. Mono pile foundation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lyngesen, S.; Brendstrup, C.

    1997-02-01

    The use of mono piles as foundations for maritime structures has been developed during the last decades. The installation requirements within the offshore sector have resulted in equipment enabling driving of piles up to 3-4 m to large penetration depths. The availability of this equipment has made the use of large mono piles feasible as foundations for structures like wind turbines. The mono pile foundations consists of three parts; the bare pile, a conical transition and a boat landing. All parts are prefitted at the yard in order to minimise the installation work that has to be carried out offshore. The study of a mono pile foundations for a 1.5 MW wind turbine has been conducted for two locations, Horns Rev and Roedsand. Three different water depths: 5, 8 and 11 m have been investigated in the study. The on-site welding between pile and conical transition is performed by an automatic welding machine. Final testing and eventually repair of the weld are conducted at least 16 hours after welding. This is followed by final installation of J-tube, tie-in to subsea cables and installation of the impressed current system for corrosive protection of the mono pile. The total cost for procurement and installation of the mono pile using the welded connection is estimated. The price does not include procurement and installation of access platform and boat landing. These costs are estimated to 250.000 DKK. Depending on water depth the cost of the pile ranges from 2,2 to 2,7 million DKK. Procurement and fabrication of the pile are approx. 75% of the total costs. The remaining 25% are due to installation. The total costs are very sensitive to the unit price of pile steel. During the project it became obvious that ice load has a very large influence on the dimensions of the mono pile. (EG)

  4. Experimental Verification of Integrity of Low-Pressure Injection Piles Structure - Pile Internal Capacity

    Science.gov (United States)

    Pachla, Henryk

    2017-12-01

    The idea of strengthening the foundation using injection piles lies in transferring loads from the foundation to the piles anchorage in existing structure and formed in the soil. Such a system has to be able to transfer loads from the foundation to the pile and from the pile onto the soil. Pile structure often reinforced with steel element has to also be able to transfer such a loading. According to the rules of continuum mechanics, the bearing capacity of such a system and a deformation of its individual elements can be determined by way of an analysis of the contact problem of three interfaces. Each of these surfaces is determined by different couples of materials. Those surfaces create: pile-foundation anchorage, bonding between reinforcement and material from which the pile is formed and pilesoil interface. What is essential is that on the contact surfaces the deformation of materials which adhere to each other can vary and depends on the mechanical properties and geometry of these surfaces. Engineering practice and experimental research point out that the failure in such structures occurs at interfaces. The paper is concentrating on presenting the experiments on interaction between cement grout and various types of steel reinforcement. The tests were conducted on the special low pressure injection piles widely used to strengthen foundations of already existing structures of historical buildings due to the technology of formation and injection pressure.

  5. Characterizing hand-piled fuels

    Science.gov (United States)

    Clinton S. Wright; Paige C. Eagle; Cameron S. Balog

    2010-01-01

    Land managers throughout the West pile and burn surface fuels to mitigate fire hazard in dry forests. Whereas piling was historically conducted with heavy machinery following commercial harvesting operations, land managers are increasingly prescribing the use of hand piling and burning to treat surface fuels created by thinning and brush cutting. An estimate of the...

  6. Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hongbo; CHEN Zhuchang

    2007-01-01

    Based on the comparative analysis of end effect on skin friction of displacement-pile (driven pile),the end effect on skin friction of bored pile is studied.The end effect on skin friction between driven pile and bored pile is different and the end effect on skin friction of bored pile is reduce of skin friction in the soil layer adjacent to the pile end.The degradation degree of skin friction is deduced with the increase of the distance from pile end.The concept of additional mud cake formed by the effect of cushion at the bottom of borehole during pouring concrete is introduced to explain the mechanism of end effect on skin friction of the bored pile.The test results of post-grouting piles indicate that the post-grouting technique is an effective way to improve the end effect on skin friction of bored pile.

  7. Screw piles for cold climate foundations

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, R.; Sakr, M. [Almita Manufacturing Ltd., Edmonton, AB (Canada)

    2008-07-01

    Almita Manufacturing is an Alberta-based company that designs and builds screw piles with its own installation teams. It also engineers and supplies piles to numerous other companies and independent installers. The company services industries such as oil and gas; power transmission and distribution; and commercial construction. This presentation discussed the design and technical aspects of screw piles. A screw pile was defined as a steel pipe shaft with a 45 degree cut at the bottom and a formed helical plate welded to the outside of the pipe near the base and at a selected point on the shaft. The pile is screwed into the ground with a planetary drive head of suitable torque rating. The helical plate or helix helps facilitate the installation of the pile and gives the screw pile increased bearing capacity and pull-out resistance over a traditional straight-shaft pile. Screw piles were compared against cast in place concrete piles and steel driven piles. Screw piles were reported to have no tailings; no concrete curing time; no rebar, anchor belts, and no liners; and no dewatering. Screw piles can also be installed in all types of weather. Rhe Cree Burn Camp case study near Fort McMurray, Alberta was also presented. This residential camp and recreation complex consists of pre-fabricated units that make up three storey housing buildings and a single floor multi-use building. The case study provided information on soil; design parameter inputs; load testing program and pile configuration; geotechnical and structural design results; compression load test arrangement; pile test setup; and test results. The presentation also discussed fabrication as well as installation equipment. Various applications were also presented through a series of project pictures. Last, the presentation provided a simple cost analysis. tabs., figs.

  8. Static and dynamic pile testing of reinforced concrete piles with structure integrated fibre optic strain sensors

    Science.gov (United States)

    Schilder, Constanze; Kohlhoff, Harald; Hofmann, Detlef; Basedau, Frank; Habel, Wolfgang R.; Baeßler, Matthias; Niederleithinger, Ernst; Georgi, Steven; Herten, Markus

    2013-05-01

    Static and dynamic pile tests are carried out to determine the load bearing capacity and the quality of reinforced concrete piles. As part of a round robin test to evaluate dynamic load tests, structure integrated fibre optic strain sensors were used to receive more detailed information about the strains along the pile length compared to conventional measurements at the pile head. This paper shows the instrumentation of the pile with extrinsic Fabry-Perot interferometers sensors and fibre Bragg gratings sensors together with the results of the conducted static load test as well as the dynamic load tests and pile integrity tests.

  9. 21 CFR 880.5180 - Burn sheet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Burn sheet. 880.5180 Section 880.5180 Food and... Burn sheet. (a) Identification. A burn sheet is a device made of a porous material that is wrapped aroung a burn victim to retain body heat, to absorb wound exudate, and to serve as a barrier against...

  10. Stability of Slopes Reinforced with Truncated Piles

    Directory of Open Access Journals (Sweden)

    Shu-Wei Sun

    2016-01-01

    Full Text Available Piles are extensively used as a means of slope stabilization. A novel engineering technique of truncated piles that are unlike traditional piles is introduced in this paper. A simplified numerical method is proposed to analyze the stability of slopes stabilized with truncated piles based on the shear strength reduction method. The influential factors, which include pile diameter, pile spacing, depth of truncation, and existence of a weak layer, are systematically investigated from a practical point of view. The results show that an optimum ratio exists between the depth of truncation and the pile length above a slip surface, below which truncating behavior has no influence on the piled slope stability. This optimum ratio is bigger for slopes stabilized with more flexible piles and piles with larger spacing. Besides, truncated piles are more suitable for slopes with a thin weak layer than homogenous slopes. In practical engineering, the piles could be truncated reasonably while ensuring the reinforcement effect. The truncated part of piles can be filled with the surrounding soil and compacted to reduce costs by using fewer materials.

  11. Piles of objects

    KAUST Repository

    Hsu, Shu-Wei; Keyser, John

    2010-01-01

    We present a method for directly modeling piles of objects in multi-body simulations. Piles of objects represent some of the more interesting, but also most time-consuming portion of simulation. We propose a method for reducing computation in many

  12. 3D FEM Analysis of a Pile-Supported Riverine Platform under Environmental Loads Incorporating Soil-Pile Interaction

    Directory of Open Access Journals (Sweden)

    Denise-Penelope N. Kontoni

    2018-01-01

    Full Text Available An existing riverine platform in Egypt, together with its pile group foundation, is analyzed under environmental loads using 3D FEM structural analysis software incorporating soil-pile interaction. The interaction between the transfer plate and the piles supporting the platform is investigated. Two connection conditions were studied assuming fixed or hinged connection between the piles and the reinforced concrete platform for the purpose of comparison of the structural behavior. The analysis showed that the fixed or hinged connection condition between the piles and the platform altered the values and distribution of displacements, normal force, bending moments, and shear forces along the length of each pile. The distribution of piles in the pile group affects the stress distribution on both the soil and platform. The piles were found to suffer from displacement failure rather than force failure. Moreover, the resulting bending stresses on the reinforced concrete plate in the case of a fixed connection between the piles and the platform were almost doubled and much higher than the allowable reinforced concrete stress and even exceeded the ultimate design strength and thus the environmental loads acting on a pile-supported riverine offshore platform may cause collapse if they are not properly considered in the structural analysis and design.

  13. The pile EL3

    International Nuclear Information System (INIS)

    Robert, J.; Raievski, V.

    1959-01-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10 14 n/cm 2 /s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [fr

  14. Swimming-pool piles

    International Nuclear Information System (INIS)

    Trioulaire, M.

    1959-01-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

  15. Experimental Verification of Integrity of Low-Pressure Injection Piles Structure – Pile Internal Capacity

    Directory of Open Access Journals (Sweden)

    Pachla Henryk

    2017-12-01

    Full Text Available The idea of strengthening the foundation using injection piles lies in transferring loads from the foundation to the piles anchorage in existing structure and formed in the soil. Such a system has to be able to transfer loads from the foundation to the pile and from the pile onto the soil. Pile structure often reinforced with steel element has to also be able to transfer such a loading. According to the rules of continuum mechanics, the bearing capacity of such a system and a deformation of its individual elements can be determined by way of an analysis of the contact problem of three interfaces. Each of these surfaces is determined by different couples of materials. Those surfaces create: pile-foundation anchorage, bonding between reinforcement and material from which the pile is formed and pilesoil interface. What is essential is that on the contact surfaces the deformation of materials which adhere to each other can vary and depends on the mechanical properties and geometry of these surfaces. Engineering practice and experimental research point out that the failure in such structures occurs at interfaces. The paper is concentrating on presenting the experiments on interaction between cement grout and various types of steel reinforcement. The tests were conducted on the special low pressure injection piles widely used to strengthen foundations of already existing structures of historical buildings due to the technology of formation and injection pressure.

  16. Characterizing Axial Stiffness of Individual Batter Piles with Emphasis on Elevated, Laterally Loaded, Clustered Pile Groups

    Science.gov (United States)

    2016-11-01

    using the appropriate stiffness based on the direction of the calculated pile load. 1...load cases. CPGA utilizes the stiffness method (Saul 1968) of three-dimensional pile group analysis for user-specified static loadings. The pile...CPGA analysis and coordinate systems (global and pile) As discussed in Chapter 1, the CPGA software utilizes the stiffness method (Saul 1968) of

  17. Modelling the pile load test

    OpenAIRE

    Prekop Ľubomír

    2017-01-01

    This paper deals with the modelling of the load test of horizontal resistance of reinforced concrete piles. The pile belongs to group of piles with reinforced concrete heads. The head is pressed with steel arches of a bridge on motorway D1 Jablonov - Studenec. Pile model was created in ANSYS with several models of foundation having properties found out from geotechnical survey. Finally some crucial results obtained from computer models are presented and compared with these obtained from exper...

  18. Use of pile driving analysis for assessment of axial load capacity of piles : [technical summary].

    Science.gov (United States)

    2012-01-01

    The dynamic response of a pile during driving is very : complex, involving the interactions of the hammer, cushion, : pile and soil during application of an impact load. : The first analysis aimed at simulating a hammer blow on : a pile was published...

  19. Modelling the pile load test

    Directory of Open Access Journals (Sweden)

    Prekop Ľubomír

    2017-01-01

    Full Text Available This paper deals with the modelling of the load test of horizontal resistance of reinforced concrete piles. The pile belongs to group of piles with reinforced concrete heads. The head is pressed with steel arches of a bridge on motorway D1 Jablonov - Studenec. Pile model was created in ANSYS with several models of foundation having properties found out from geotechnical survey. Finally some crucial results obtained from computer models are presented and compared with these obtained from experiment.

  20. Laterally Loaded Piles in Clay

    DEFF Research Database (Denmark)

    Christensen, Helle; Niewald, Gitte

    1992-01-01

    The ultimate lateral resistance of a pile element moved horizontally can be analyzed by the theory of plasticity. At a certain depth the movements around the pile are purely horizontal and upper bound solutions can be estimated theoretically under undrained circumstances. Model tests...... in the laboratory show ultimate resistances close to the estimated limits and p - y curves close to curves based on test results from full-scale piles. Rough and smooth piles with circular and square cross sections are investigated....

  1. Analysis of pile foundations under dynamic loads

    International Nuclear Information System (INIS)

    Waas, G.; Hartmann, H.G.

    1981-01-01

    A method is presented for the analysis of pile foundations which are subjected to horizontal dynamic loads from earthquakes, airplane impact, gas explosion or other sources. The motion of the pile cap and the pile forces are computed. - The loads may be applied to the pile cap or directly to the piles (e.g. by earthquake wave motion). The soil may be stratified and is considered to be an elastic or visco-elastic medium. The piles are assumed vertical. The method makes use of an approximate fundamental solution for displacements caused by a dynamic point load in a layered visco-elastic medium. The approximation involves a discretization of the medium in the vertical direction. In horizontal directions the medium is treated by continuum theory. The soil medium supports each pile at about 10 to 20 nodes. A dynamic flexiblity matrix for the soil is derived which relates the elastic, damping and inertial forces of the soil to the displacements at each node. It includes effects of radiation damping. All piles are coupled through the soil flexibility matrix. The piles are modelled by beam elements. Transient response is computed using fast discrete Fourier transforms. The arrangement of the piles is arbitrary. However, simple and double symmetry can be accounted for by the computer program. When the pile arrangement is axisymmetric, the degrees of freedom can be reduced to only those of two piles per ring. The influence of the number of piles and the influence of the pile spacing on group stiffness and on pile forces is presented for two soil profiles. Dynamic effects on pile forces of a foundation for a reactor building are studied. They are significant when soils are soft. (orig.)

  2. 40 CFR 264.554 - Staging piles.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Staging piles. 264.554 Section 264.554... for Cleanup § 264.554 Staging piles. This section is written in a special format to make it easier to... staging pile? A staging pile is an accumulation of solid, non-flowing remediation waste (as defined in...

  3. Pullout capacity of batter pile in sand.

    Science.gov (United States)

    Nazir, Ashraf; Nasr, Ahmed

    2013-03-01

    Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Also most of retaining walls are subjected to horizontal forces and bending moments, these forces are due to earth pressure. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under axial pullout is not well established. In order to delineate the significant variables affecting the ultimate uplift shaft resistance of batter pile in dry sand, a testing program comprising 62 pullout tests was conducted. The tests are conducted on model steel pile installed in loose, medium, and dense sand to an embedded depth ratio, L/d, vary from 7.5 to 30 and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile constructed in dense and/or medium density sand increases with the increase of batter angle attains maximum value and then decreases, the maximum value of Pα occurs at batter angle approximately equal to 20°, and it is about 21-31% more than the vertical pile capacity, while the pullout capacity for batter pile that constructed in loose sand decreases with the increase of pile inclination. The results also indicated that the circular pile is more resistant to pullout forces than the square and rectangular pile shape. The rough model piles tested is experienced 18-75% increase in capacity compared with the smooth model piles. The suggested relations for the pullout capacity of batter pile regarding the vertical pile capacity are well predicted.

  4. Pullout capacity of batter pile in sand

    Directory of Open Access Journals (Sweden)

    Ashraf Nazir

    2013-03-01

    Full Text Available Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. Also most of retaining walls are subjected to horizontal forces and bending moments, these forces are due to earth pressure. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under axial pullout is not well established. In order to delineate the significant variables affecting the ultimate uplift shaft resistance of batter pile in dry sand, a testing program comprising 62 pullout tests was conducted. The tests are conducted on model steel pile installed in loose, medium, and dense sand to an embedded depth ratio, L/d, vary from 7.5 to 30 and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile constructed in dense and/or medium density sand increases with the increase of batter angle attains maximum value and then decreases, the maximum value of Pα occurs at batter angle approximately equal to 20°, and it is about 21–31% more than the vertical pile capacity, while the pullout capacity for batter pile that constructed in loose sand decreases with the increase of pile inclination. The results also indicated that the circular pile is more resistant to pullout forces than the square and rectangular pile shape. The rough model piles tested is experienced 18–75% increase in capacity compared with the smooth model piles. The suggested relations for the pullout capacity of batter pile regarding the vertical pile capacity are well predicted.

  5. Evaluation of axial pile bearing capacity based on pile driving analyzer (PDA) test using Neural Network

    Science.gov (United States)

    Maizir, H.; Suryanita, R.

    2018-01-01

    A few decades, many methods have been developed to predict and evaluate the bearing capacity of driven piles. The problem of the predicting and assessing the bearing capacity of the pile is very complicated and not yet established, different soil testing and evaluation produce a widely different solution. However, the most important thing is to determine methods used to predict and evaluate the bearing capacity of the pile to the required degree of accuracy and consistency value. Accurate prediction and evaluation of axial bearing capacity depend on some variables, such as the type of soil, diameter, and length of pile, etc. The aims of the study of Artificial Neural Networks (ANNs) are utilized to obtain more accurate and consistent axial bearing capacity of a driven pile. ANNs can be described as mapping an input to the target output data. The method using the ANN model developed to predict and evaluate the axial bearing capacity of the pile based on the pile driving analyzer (PDA) test data for more than 200 selected data. The results of the predictions obtained by the ANN model and the PDA test were then compared. This research as the neural network models give a right prediction and evaluation of the axial bearing capacity of piles using neural networks.

  6. The Windscale piles - past, present and future

    International Nuclear Information System (INIS)

    Jones, J.M.; Adams, A.L.

    1987-01-01

    The paper concerns the Windscale reactor piles, in which a fire occurred in the core of pile 1 thirty years ago. A description is given of the two Windscale piles, along with the events leading up to the accident, and the state of the piles following shutdown. The surveillance and maintenance to ensure that the pile and associated buildings were in a safe condition is outlined. The present state of the core, water ducts and pile chimneys is described. The present and future programme of work to ensure long term safety is discussed. This includes the initial steps in decommissioning of the piles. (U.K.)

  7. Simplified analysis of laterally loaded pile groups

    Directory of Open Access Journals (Sweden)

    F.M. Abdrabbo

    2012-06-01

    Full Text Available The response of laterally loaded pile groups is a complicated soil–structure interaction problem. Although fairly reliable methods are developed to predicate the lateral behavior of single piles, the lateral response of pile groups has attracted less attention due to the required high cost and complication implication. This study presents a simplified method to analyze laterally loaded pile groups. The proposed method implements p-multiplier factors in combination with the horizontal modulus of subgrade reaction. Shadowing effects in closely spaced piles in a group were taken into consideration. It is proven that laterally loaded piles embedded in sand can be analyzed within the working load range assuming a linear relationship between lateral load and lateral displacement. The proposed method estimates the distribution of lateral loads among piles in a pile group and predicts the safe design lateral load of a pile group. The benefit of the proposed method is in its simplicity for the preliminary design stage with a little computational effort.

  8. Pile Load Capacity – Calculation Methods

    Directory of Open Access Journals (Sweden)

    Wrana Bogumił

    2015-12-01

    Full Text Available The article is a review of the current problems of the foundation pile capacity calculations. The article considers the main principles of pile capacity calculations presented in Eurocode 7 and other methods with adequate explanations. Two main methods are presented: α – method used to calculate the short-term load capacity of piles in cohesive soils and β – method used to calculate the long-term load capacity of piles in both cohesive and cohesionless soils. Moreover, methods based on cone CPTu result are presented as well as the pile capacity problem based on static tests.

  9. Static pile load tests on driven piles in Intermediate-Geo Materials : research brief.

    Science.gov (United States)

    2017-02-01

    Research Objectives: : Investigate the use of modified standard penetration tests (MSPT) : Compare field results with predictions made by the WisDOT driving formula, PDA and CAPWAP : Improve prediction of pile lengths and pile capacities ...

  10. Test Exponential Pile

    Science.gov (United States)

    Fermi, Enrico

    The Patent contains an extremely detailed description of an atomic pile employing natural uranium as fissile material and graphite as moderator. It starts with the discussion of the theory of the intervening phenomena, in particular the evaluation of the reproduction or multiplication factor, K, that is the ratio of the number of fast neutrons produced in one generation by the fissions to the original number of fast neutrons, in a system of infinite size. The possibility of having a self-maintaining chain reaction in a system of finite size depends both on the facts that K is greater than unity and the overall size of the system is sufficiently large to minimize the percentage of neutrons escaping from the system. After the description of a possible realization of such a pile (with many detailed drawings), the various kinds of neutron losses in a pile are depicted. Particularly relevant is the reported "invention" of the exponential experiment: since theoretical calculations can determine whether or not a chain reaction will occur in a give system, but can be invalidated by uncertainties in the parameters of the problem, an experimental test of the pile is proposed, aimed at ascertaining if the pile under construction would be divergent (i.e. with a neutron multiplication factor K greater than 1) by making measurements on a smaller pile. The idea is to measure, by a detector containing an indium foil, the exponential decrease of the neutron density along the length of a column of uranium-graphite lattice, where a neutron source is placed near its base. Such an exponential decrease is greater or less than that expected due to leakage, according to whether the K factor is less or greater than 1, so that this experiment is able to test the criticality of the pile, its accuracy increasing with the size of the column. In order to perform this measure a mathematical description of the effect of neutron production, diffusion, and absorption on the neutron density in the

  11. Test Pile Reactivity Loss Due to Trichloroethylene

    International Nuclear Information System (INIS)

    Plumlee, K.E.

    2001-01-01

    The presence of trichloroethylene in the test pile caused a continual decrease in pile reactivity. A system which removed, purified, and returned 12,000 cfh helium to the pile has held contamination to a negligible level and has permitted normal pile operation

  12. Simulation of bearing capacity of bored piles

    Directory of Open Access Journals (Sweden)

    Majeed Ahmed

    2018-01-01

    Full Text Available This study focuses on how one can possibly predict the ultimate load for the piles that did not reach failure. This challenge was acquired through Chin- Konder method by which, the estimated settlement that correspond to failure load is well defined. Hence, this research aims to make a comparative study between the results of pile load tests carried out in Al-Basrah sewage treatment plant project, and those results induced from the numerical analysis in term of ultimate pile capacity. Consequently, it may give a clear idea on the ability of numerical simulation in getting close to the actual behavior of piles. In the current study, a numerical study using Plaxis 3D Foundation program has been performed on bored piles by the assistance of site investigations of soil. Mohr- Coulomb and linear elastic models were adopted in the simulation for soil and pile respectively. Ten bored piles were used in this analysis under different values of loading. The diameter and length of pile are 0.6m and 24m respectively. The test results indicate that, an excellent agreement has been found as a response of pile capacity between the field and numerical studies. Also, ideal load- settlement curves were created using Chin- Konder method to predict the failure load of bored piles. Also, the results have demonstrated that, the pile capacity obtained from the simulation process is larger about 51% than that design load estimated before the design of piles. This may present a priority to use the finite element method to be accounted as an effective approach in the primary analysis.

  13. Pile Model Tests Using Strain Gauge Technology

    Science.gov (United States)

    Krasiński, Adam; Kusio, Tomasz

    2015-09-01

    Ordinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine the total bearing capacity of the pile, without the knowledge of its distribution into the shaft and base resistances. Much more information can be obtained by carrying out a test of instrumented pile equipped with a system for measuring the distribution of axial force along its core. In the case of pile model tests the use of such measurement is difficult due to small scale of the model. To find a suitable solution for axial force measurement, which could be applied to small scale model piles, we had to take into account the following requirements: - a linear and stable relationship between measured and physical values, - the force measurement accuracy of about 0.1 kN, - the range of measured forces up to 30 kN, - resistance of measuring gauges against aggressive counteraction of concrete mortar and against moisture, - insensitivity to pile bending, - economical factor. These requirements can be fulfilled by strain gauge sensors if an appropriate methodology is used for test preparation (Hoffmann [1]). In this paper, we focus on some aspects of the application of strain gauge sensors for model pile tests. The efficiency of the method is proved on the examples of static load tests carried out on SDP model piles acting as single piles and in a group.

  14. Safety precautions in atomic pile control (1962)

    International Nuclear Information System (INIS)

    Furet, J.

    1962-01-01

    We have been led to study the problem of safety in atomic pile control as a result of our participation on the one hand in the planning of C.E.A. atomic piles, and on the other hand in the pile safety sub omission considering atomic pile safety of operational or planned C.E.A. piles. We have thus had to consider the wishes occurring in piles during their operation and also their behaviour in the dynamic state The present work deals mainly with the importance of intrinsic safety devices, with the influence of reactivity variations on the power fluctuations during accidental operation, and with the development of robust and reliable safety appliances. The starting p accident has been especially studied both for low-flux piles where a compromise is necessary between the response time of the safety appliances and the statistical fluctuations and for high lux piles where xenon poisoning has an effect on the lower limit of the velocity of reactivity liberation. The desirability has been stressed of automation as a safety factor in atomic pile control. The details required for an understanding of the diagrams of the apparatus are given. (author) [fr

  15. Piles of dislocation loops in real crystals

    International Nuclear Information System (INIS)

    Dubinko, V.I.; Turkin, A.A.; Yanovskij, V.V.

    1985-01-01

    Behaviour of piles of dislocation loops in crystals was studied in order to define metal swelling under irradiation. Energy of pile interaction with point defects and intrinsic pile energy are studied in the framework of the linear elasticity theory. Preference of dislocation pile calculated in the paper decreases with radiation dose hence, material swelling rate also decreases. Creation of conditions, which assume an existence of piles of dislocation loops being stable under irradiation, is of particular interest

  16. 30 CFR 77.214 - Refuse piles; general.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; general. 77.214 Section 77.214... Installations § 77.214 Refuse piles; general. (a) Refuse piles constructed on or after July 1, 1971, shall be..., tipples, or other surface installations and such piles shall not be located over abandoned openings or...

  17. Summary on out-of-pile and in-pile properties of M5 alloy

    International Nuclear Information System (INIS)

    Zhao Wenjin

    2001-01-01

    The out-of-pile and in-pile corrosion, mechanical properties, microstructure,hydrogen absorption, creep and growth resistances of M5 alloy using as PWR fuel rod cladding materials developed by FRAMATOME in France has been summarized with reference to the literatures. The results obtained from in-pile irradiation tests show that the corrosion and hydrogen absorption resistances, creep and irradiation growth resistances of M5 alloy cladding are superior to that of the optimized Zircaloy-4. It could be estimated that the M5 alloy enables rod burnups close to 65GWd/tU to be reached

  18. A computational model of pile vertical vibration in saturated soil based on the radial disturbed zone of pile driving

    International Nuclear Information System (INIS)

    Li Qiang; Shi Qian; Wang Kuihua

    2010-01-01

    In this study, a simplified computational model of pile vertical vibration was developed. The model was based on the inhomogeneous radial disturbed zone of soil in the vicinity of a pile disturbed by pile driving. The model contained two regions: the disturbed zone, which was located in the immediate vicinity of the pile, and the undisturbed region, external to the disturbed zone. In the model, excess pore pressure in the disturbed zone caused by pile driving was assumed to follow a logarithmic distribution. The relationships of stress and strain in the disturbed zone were based on the principle of effective stress under plain strain conditions. The external zone was governed by the poroelastic theory proposed by Biot. With the use of a variable separation method, an analytical solution in the frequency domain was obtained. Furthermore, a semi-analytical solution was attained by employing a numerical convolution method. Numerical results from the frequency and time domain indicated that the equivalent radius of the disturbed zone and the ratio of excess pore pressure had a significant effect on pile dynamic response. However, actual interactions between pile and soil will be weaker due to the presence of the radial disturbed zone, which is caused by pile driving. Consequently, the ideal undisturbed model overestimates the interaction between pile and soil; however, the proposed model reflects the interaction of pile and soil better than the perfect contact model. Numerical results indicate that the model can account for the time effect of pile dynamic tests.

  19. Some Remarks on Foundation Pile Testing Procedures

    Science.gov (United States)

    Rybak, Jarosław

    2017-10-01

    This work presents the review of pile capacity testing techniques. In an overview, the key points in pile designing are: determination of the appropriate computational schemes, reliable data on loads and the properties of structural materials (in particular, of the soil mass, which is marked by the greatest variability). The procedure of constructing a pile foundation should include: carrying out soil tests in the scope that ensures safe designing, selecting a piling technology that is relevant both to geotechnical conditions and expected loads, drafting a piling design together with the design of load tests, setting up a testing station for further load tests, static and/or dynamic tests of pile load capacity, preceded by supplementary soil tests when the conditions of test pile installation fail to comply with the design assumptions or when the pile length exceeds the depth of the previously investigated soil, making documentation of load capacity tests (with an additional correction of the piling design), the actual piling (ongoing analysis of pile driving logs and, if necessary, testing the piles’ integrity), drawing up the as-built documentation. Unfortunately, the design is corrected after the load test have been conducted only if the piles fail to show the designed bearing capacity. The designer is then obliged to revise the design assumptions on the basis of tests results. If the test results account for the a greater bearing capacity than necessary and it would be recommendable to limit the extent of the planned (i.e. set out in the contract) piling works, usually neither the contractor nor the designer, nor even the Construction Site Supervisor, acting for the benefit of the Investor, are willing to take on the responsibility for reducing the scope of the piling works. The necessity of conducting additional control tests before and during the implementation of the construction project is often treated by the investors as an attempt at extorting extra

  20. Literature review Quasi-static and Dynamic pile load tests : Primarily report on non-static pile load tests

    NARCIS (Netherlands)

    Huy, N.Q.

    2010-01-01

    Pile testing, which plays an importance role in the field of deep foundation design, is performed by static and non-static methods to provide information about the following issues: (Poulos, 1998) - The ultimate capacity of a single pile. - The load-displacement behavior of a pile. - The performance

  1. Introduction to Single Piles under Lateral Loading

    DEFF Research Database (Denmark)

    Augustesen, Anders; Ibsen, Lars Bo

    .2). The description is based on results of laboratory tests, full-scale field tests as well as numerical investigations presented in literature. Second, general methods that attempt to model lateral pile response are discussed in section 1.4. Third, focus is paid to a widely used method for prediction of the response......The purpose of this chapter is to give a short introduction to single piles subjected to lateral loading. First, the observed behaviour of laterally loaded piles is described, i.e. the effects of loading conditions, installation procedure, pile type etc. on pile behaviour are presented (section 1...... of a lateral loaded pile, namely the Winkler approach in which the pile is modelled as an elastic beam on an elastic foundation (section 1.5). The soil response and thereby the elastic foundation is represented by springs with nonlinear behaviour (p-y curves). In section 1.6 different types and formulations...

  2. Multisignal detecting system of pile integrity testing

    Science.gov (United States)

    Liu, Zuting; Luo, Ying; Yu, Shihai

    2002-05-01

    The low strain reflection wave method plays a principal rule in the integrating detection of base piles. However, there are some deficiencies with this method. For example, there is a blind area of detection on top of the tested pile; it is difficult to recognize the defects at deep-seated parts of the pile; there is still the planar of 3D domino effect, etc. It is very difficult to solve these problems only with the single-transducer pile integrity testing system. A new multi-signal piles integrity testing system is proposed in this paper, which is able to impulse and collect signals on multiple points on top of the pile. By using the multiple superposition data processing method, the detecting system can effectively restrain the interference and elevate the precision and SNR of pile integrity testing. The system can also be applied to the evaluation of engineering structure health.

  3. Test Setup for Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The test setup for testing axially static and cyclic loaded piles in sand is described in the following. The purpose for the tests is to examine the tensile capacity of axially loaded piles in dense fully saturated sand. The pile dimensions are chosen to resemble full scale dimension of piles used...... in offshore pile foundations today....

  4. Piles of dislocation loops in real crystals. 2. Evolution of dislocation piles under irradiation

    International Nuclear Information System (INIS)

    Dubinko, V.I.; Turkin, A.A.; Yanovskij, V.V.

    1985-01-01

    The given paper considers evolution of piles in a real molybdenum crystal under neutron irradiation. Obtained was a stability criterium, when meeting it interstitial piles (one-dimensional periodical structures of interstitial loops) in the crystal tend to stationary state under the irradiation and, when disturbing the criterium, they disintegrate into rapidly growing interstitial isolated loops. It was also shown that the generation of dense vacancy piles results in the formation of an ordering structure of isolated vacancy loops. Theoretical results agree good with experimental data

  5. Energy piles. A fundamental energy pile; Energiepfaehle. Eine fundamentale Energiequelle

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Holger; Beldermann, Nico [GF-Tec GmbH, Roedermark (Germany)

    2013-03-01

    The Maintower, the new airport in Berlin/Brandenburg, a lot of Ikea buildings, and also small office buildings or residential buildings may exchange energy with the underground by means of pile fundaments. At the correct planning and execution, energy piles are low-cost geothermal power plants which sustainable generate heating and cooling for the buildings standing on them. Even more energy can be generated safely under compliance with the groundwater protection by means of a new development of the material and the transfer.

  6. Pile Design Based on Cone Penetration Test Results

    OpenAIRE

    Salgado, Rodrigo; Lee, Junhwan

    1999-01-01

    The bearing capacity of piles consists of both base resistance and side resistance. The side resistance of piles is in most cases fully mobilized well before the maximum base resistance is reached. As the side resistance is mobilized early in the loading process, the determination of pile base resistance is a key element of pile design. Static cone penetration is well related to the pile loading process, since it is performed quasi-statically and resembles a scaled-down pile load test. In ord...

  7. Mitigation of Ground Vibration by Double Sheet-pile Walls

    DEFF Research Database (Denmark)

    Andersen, Lars; Frigaard, Peter; Augustesen, Anders

    2008-01-01

    Open trenches are an effective means of vibration mitigation, but they cannot be established in practice. When the trenches are covered by a concrete pavement, part of the efficiency may be lost. However, the present analysis indicates that barriers of this kind may still lead to a significant re...... reduction of the horizontal and vertical vibrations caused by traffic at a nearby road or railway....

  8. Tuning the p-type Schottky barrier in 2D metal/semiconductor interface:boron-sheet on MoSe2, and WSe2

    Science.gov (United States)

    Couto, W. R. M.; Miwa, R. H.; Fazzio, A.

    2017-10-01

    Van der Waals (vdW) metal/semiconductor heterostructures have been investigated through first-principles calculations. We have considered the recently synthesized borophene (Mannix et al 2015 Science 350 1513), and the planar boron sheets (S1 and S2) (Feng et al 2016 Nat. Chem. 8 563) as the 2D metal layer, and the transition metal dichalcogenides (TMDCs) MoSe2, and WSe2 as the semiconductor monolayer. We find that the energetic stability of those 2D metal/semiconductor heterojunctions is mostly ruled by the vdW interactions; however, chemical interactions also take place in borophene/TMDC. The electronic charge transfer at the metal/semiconductor interface has been mapped, where we find a a net charge transfer from the TMDCs to the boron sheets. Further electronic structure calculations reveal that the metal/semiconductor interfaces, composed by planar boron sheets S1 and S2, present a p-type Schottky barrier which can be tuned to a p-type ohmic contact by an external electric field.

  9. Test Procedure for Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The test procedure described in the following is used when examining the effects of static or cyclic loading on the skin friction of an axially loaded pile in dense sand. The pile specimen is only loaded in tension to avoid any contribution from the base resistance. The pile dimensions are chosen...... to resemble full scale dimension of piles used in offshore pile foundations today. In this report is given a detailed description of the soil preparation and pile installation procedures as well data acquisition methods....

  10. Full Scale Model Test of Consolidation Acceleration on Soft Soil deposition with Combination of Timber Pile and PVD (Hybrid Pile)

    OpenAIRE

    Sandyutama, Y.; Samang, L.; Imran, A. M.; Harianto4, T.

    2015-01-01

    This research aims to analyze the effect of composite pile-PVD (hybrid pile) as the reinforcement in embankment on soft soil by the means of numerical simulation and Full-Scale Trial Embankment. The first phase cunducted by numerical analysis and obtained 6-8 meters hybrid pile length effective. Full-Scale trial embankment. was installed hybrid pile of 6 m and preloading of 4,50 height. Full-scale tests were performed to investigate the performances of Hybrid pile reinforcement. This research...

  11. Pulse pile-up IV

    International Nuclear Information System (INIS)

    Wilkinson, D.H.

    1991-05-01

    The study of pulse pile-up is extended from the case of unipolar pulses, for which ruin theory is an excellent approximation, to the case of bipolar pulses for which ruin theory is not applicable to the effect of the back-kicks in reducing the pile-up: an appropriate solution is presented. (Author) 3 refs., 11 figs

  12. Introduction of effective piles in a base structure

    Directory of Open Access Journals (Sweden)

    В.Б. Кашка

    2005-03-01

    Full Text Available  Design features of effective piles such as СВ and their advantages in use are considered at the device of the pile bases in comparison with widely widespread types of piles. From results of comparative tests of piles under static pressing loading in different earth conditions the tendency of redistribution of bearing (carrying ability between a trunk and expansions an effective pile such as СВ was determined on earth conditions.

  13. The Windscale piles initial decommissioning programme

    International Nuclear Information System (INIS)

    Boorman, T.; Woodacre, A.

    1992-01-01

    The two Windscale Piles, the first large scale nuclear reactors built in the UK were constructed in the late 1940's and operated until the accident in Pile No 1 caused their permanent shutdown in 1957. Following a period of care and maintenance, a programme of initial decommissioning has begun aimed at establishing a satisfactory long-term safe condition for the Windscale Piles Complex with minimum maintenance commitments. For the chimneys this involves the removal of the top filter sections. The pond will be emptied and cleaned. For the Piles the initial phase includes the consideration of options for long-term decommissioning solutions. (author)

  14. Starting up a programme of atomic piles using compressed gas; Le demarrage d'un programme de piles atomiques a gaz comprime

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, J; Yvon, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-01

    1) An examination of the intellectual and material resources which have directed the French programme towards: a) the natural uranium and plutonium system, b) the use of compressed gas as heat transfer fluid (primary fluid). 2) The parts played in exploring the field by the pile EL2 and G1, EL2 a natural uranium, heavy water and compressed gas pile, G1 a natural uranium, graphite and atmospheric air pile. 3) Development of the neutronics of graphite piles: physical study of G1. 4) The examination of certain problem posed by centres equipped with natural uranium, graphite and compressed carbon dioxide piles: structure, special materials, fluid circuits, maximum efficiency. Economic aspects. 5) Aids to progress: a) piles for testing materials and for tests on canned fuel elements, b) laboratory and calculation facilities. 6) Possible new orientations of compressed gas piles: a) raising of the pressure, b) enriched fuel, c) higher temperatures, d) use of heavy water. (author) [French] 1) Examen des ressources - intellectuelles et materielles - qui ont oriente le programme fran is vers: a) la voie de l'uranium naturel et du plutonium; b) l'emploi comme fluide pour le transfert de la chaleur (fluide primaire) d'un gaz comprime. 2) Le role d'exploration des piles EL2 et G1, EL2 pile a uranium naturel, eau lourde et gaz comprime, G1 pile a uranium naturel, graphite et air atmospherique. 3) Developpement de la neutronique des piles a graphite: l'etude physique de G1. 4) Examen de certains problemes poses par les centrales equipees de piles a uranium naturel, graphite et gaz carbonique comprime: structure, materiaux speciaux, circuits de fluides, optimisation. Aspects economiques. 5) Les auxiliaires du progres: a) piles pour essai de materiaux et pour essais de cartouches, b) moyens de laboratoire et moyens de calcul. 6) Orientations nouvelles possibles des piles a gaz comprime: a) elevation de la pression, b) combustible enrichi, c) temperatures elevees, d) emploi de l

  15. New trends in pile safety instrumentation; Les tendances nouvelles dans l'instrumentation de securite des piles

    Energy Technology Data Exchange (ETDEWEB)

    Furet, J.

    1961-04-19

    This report addresses the protection of nuclear piles against damages due to operation incidents. The author discusses the current trends in the philosophy of safety of atomic power piles, identifies the parameters which define safety systems, presents tests to be performed on safety chains, comments the relationship between safety and the decrease of the number of pile inadvertent shutdowns, discusses the issues of instrument failures and chain multiplicity, comments the possible improvement of the operation of elements which build up safety chains (design simplification, development of semiconductors, replacement of electromechanical relays by static relays), the role of safety logical computers and the development of automatics in pile safety, presents automatic control as a safety factor (example of automatic start-up), and finally comments the use of fuses.

  16. Reliability of Estimation Pile Load Capacity Methods

    Directory of Open Access Journals (Sweden)

    Yudhi Lastiasih

    2014-04-01

    Full Text Available None of numerous previous methods for predicting pile capacity is known how accurate any of them are when compared with the actual ultimate capacity of piles tested to failure. The author’s of the present paper have conducted such an analysis, based on 130 data sets of field loading tests. Out of these 130 data sets, only 44 could be analysed, of which 15 were conducted until the piles actually reached failure. The pile prediction methods used were: Brinch Hansen’s method (1963, Chin’s method (1970, Decourt’s Extrapolation Method (1999, Mazurkiewicz’s method (1972, Van der Veen’s method (1953, and the Quadratic Hyperbolic Method proposed by Lastiasih et al. (2012. It was obtained that all the above methods were sufficiently reliable when applied to data from pile loading tests that loaded to reach failure. However, when applied to data from pile loading tests that loaded without reaching failure, the methods that yielded lower values for correction factor N are more recommended. Finally, the empirical method of Reese and O’Neill (1988 was found to be reliable enough to be used to estimate the Qult of a pile foundation based on soil data only.

  17. 30 CFR 77.215-4 - Refuse piles; abandonment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; abandonment. 77.215-4 Section 77... MINES Surface Installations § 77.215-4 Refuse piles; abandonment. When a refuse pile is to be abandoned... refuse pile shall be abandoned in accordance with a plan submitted by the operator and approved by the...

  18. Seismic behavior analysis of piled drums

    International Nuclear Information System (INIS)

    Aoki, H.; Kosaka, T.; Mizushina, T.; Shimizu, M.; Uji, S.; Tsuchiya, H.

    1987-01-01

    In general, low level radioactive waste is packed in drums and stored in a warehouse being piled vertically, or laid horizontally. To observe the behavior of piled drums during an earthquake, an experimental study was reported. The experimental study is limited by the vibrating platform capacity. To carry out these tests up to the supporting limit is not recommended, in view of the vibrating platform curing as well as the operators' security. It is very useful to develop the analytical method for simulating the behavior of the drums. In this report, a computer program of piled drum's dynamic motion is shown, and the analytical result is referred to the experimental result. From the result of experiment on piled drums, the sliding effect has been found to be very important for the stability of drum, and the rocking motion observed, showing a little acceleration is less than the static estimated value. Behavior of piled drums is a complex phenomena comprising of sliding, rocking and jumping

  19. Attenuation of pressure dips underneath piles of spherocylinders.

    Science.gov (United States)

    Zhao, Haiyang; An, Xizhong; Gou, Dazhao; Zhao, Bo; Yang, Runyu

    2018-05-30

    The discrete element method (DEM) was used to simulate the piling of rod-like (elongated sphero-cylindrical) particles, mainly focusing on the effect of particle shape on the structural and force properties of the piles. In this work, rod-like particles of different aspect ratios were discharged on a flat surface to form wedge-shaped piles. The surface properties of the piles were characterized in terms of angle of repose and stress at the bottom of the piles. The results showed that the rise of the angle of repose became slower with the increase of particle aspect ratio. The pressure dip underneath the piles reached the maximum when the particle aspect ratio was around 1.6, beyond which the pressure dip phenomenon became attenuated. Both the pressure dip and the shear stress dip were quantitatively examined. The structure and forces inside the piles were further analyzed to understand the change in pressure dip, indicating that "bridging" or "arching" structures within the piles were the cause of the pressure dip.

  20. Impedance function of a group of vertical piles

    International Nuclear Information System (INIS)

    Wolf, J.P.; Arx, G.A. von

    1978-01-01

    Impedance and transfer functions of a group of vertical piles located in any desired configuration in plan in a horizontally stratified soil layer are derived. Hysteretic and radiation damping are accounted for. The method separates the piles and the soil, introducing unknown interaction forces. The total flexibility matrix of the soil is constructed, superposing the (complex) flexibility coefficients caused by the interaction forces of a single pile only. The dependence of the impedance and transfer functions on the oscllating frequency for foundations with different numbers of piles is investigated. Pile-soil-pile interaction is shown to be very important for all modes of vibration. The procedure is used in the seismic analysis of a reactor building. (Author)

  1. 30 CFR 817.83 - Coal mine waste: Refuse piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal mine waste: Refuse piles. 817.83 Section... ACTIVITIES § 817.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 817.81, the... drainage may not be diverted over the outslope of the refuse pile. Runoff from areas above the refuse pile...

  2. Nanoindentation-induced pile-up in hydrogenated amorphous silicon

    International Nuclear Information System (INIS)

    Pantchev, B; Danesh, P; Wiezorek, J; Schmidt, B

    2010-01-01

    Nanoindentation-induced material extrusion around the nanoindent (pile-up) leads to an overestimation of elastic modulus, E, and nanohardness, H, when the test results are evaluated using the Oliver and Pharr method. Factors affecting the pile-up during testing are residual stresses in film and ratio of film and substrate mechanical properties. Nanoindentation of hydrogenated amorphous silicon (a-Si:H) films has been carried out with the aim to study the effect of residual compressive stress on the pile-up in this material. To distinguish the contribution of compressive stress to the appearance of pile-up ion implantation has been used as a tool, which reduces the compressive stress in a-Si:H. Scanning probe microscope has been used for the imaging of the indent and evaluation of the pile-up. The values of E and H have been obtained from the experimental load-displacement curves using depth profiling with Berkovich tip, which has created negligible pile-up. A sharper cube corner tip has been used to study the pile-up. It has been established that pile-up is determined by the material plasticity, when the compressive stress is below 200 MPa. The contribution of mechanical stress to the pile-up is essential for the stress as high, as about 500 MPa.

  3. 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

  4. Pile foundation response in liquefiable soil deposit during strong earthquakes. ; Centrifugal test for pile foundation model and correlation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Y.; Miura, K. (Kajima Corp., Tokyo (Japan)); Scott, R.; Hushmand, B. (California Inst. of Technology, California, CA (United States))

    1992-09-30

    For the purpose of studying the pile foundation response in liquefiable soil deposit during earthquakes, a centrifugal loading system is employed which can reproduce the stress conditions of the soil in the actual ground, and earthquake wave vibration tests are performed in dry and saturated sand layers using a pile foundation model equipped with 4 piles. In addition, the result of the tests is analyzed by simulation using an analytic method for which effective stress is taken into consideration to investigate the effectiveness of this analytical model. It is clarified from the result of the experiments that the bending moment of the pile and the response characteristics of the foundation in the pile foundation response in saturated sand are greatly affected by the longer period of acceleration wave form of the ground and the increase in the ground displacement due to excess pore water pressure buildup. It is shown that the analytical model of the pile foundation/ground system is appropriate, and that this analytical method is effective in evaluating the seismic response of the pile foundation in nonlinear liquefiable soil. 23 refs., 21 figs., 3 tabs.

  5. Analysis of Dynamic Stiffness of Bridge Cap-Pile System

    Directory of Open Access Journals (Sweden)

    Jinhui Chu

    2018-01-01

    Full Text Available In order to investigate the applicability of dynamic stiffness for bridge cap-pile system, a laboratory test was performed. A numerical model was also built for this type of system. The impact load was applied on the cap top and the dynamic stiffness was analysed. Then, the effect of the effective friction area between pile and soil was also considered. Finally, the dynamic stiffness relationship between the single pile and the cap-pile system was also compared. The results show that the dynamic stiffness is a sensitive index and can well reflect the static characteristics of the pile at the elastic stage. There is a significant positive correlation between the vertical dynamic stiffness index and bearing capacity of the cap-pile system in the similar formation environment. For the cap-pile system with four piles, the dynamic stiffness is about four times as large as the single pile between 10 and 20 Hz.

  6. Integrity and As-built capacity of bored pile group

    International Nuclear Information System (INIS)

    Shaw, D.E.; Kissenpfennig, J.F.; Huemmer, M.R.

    1983-01-01

    This paper discusses the application of statistical methods to the reliability evaluation of cast-in-place concrete piles. The difficulties associated with pile construction can lead to larger uncertainties than would be associated with normal reinforced concrete structures both due to uncertainty in concrete quality and end bearing capacity. These uncertainties can be dealt with through the use of statistical methods. A statistical model of an individual pile is formulated along with a methodology for determining necessary statistical parameters from results of concrete batch tests, core strength tests and visual logs, sonic geophysical testing methods, and proof tests. Strength models for both static vertical and seismic horizontal loadings are discussed. The overall safety of a pile foundation is dependent upon the distribution of individual pile strength as well as the additional reliability due to the use of a large number of parallel load paths provided by a pile group foundation. The paper presents a mechanical model of global pile behavior which accounts for individual pile ductility along with the possibility of redistribution of loads from weaker to stronger piles. The use of the Monte Carlo method to determine the overall reliability of the pile foundation is discussed. Numerical results for both individual pile behavior as well as overall foundation behavior are presented. (orig.)

  7. Thermomechanical Behavior of Energy Pile Embedded in Sandy Soil

    Directory of Open Access Journals (Sweden)

    Xu Huang

    2018-01-01

    Full Text Available The traditional energy pile (solid energy pile has been implemented for decades. However, the design of different kinds of energy piles is still not well understood. In this study, a series of model tests were performed on an aluminum pipe energy pile (PEP in dry sandy soil to investigate the thermal effects on the mechanical behaviors of pipe energy pile. The thermal responses of the PEP were also analyzed. Steady temperatures of the PEP under different working conditions were also compared with that of the solid energy pile. Different loading tests were carried out on four pipe energy piles under three different temperatures of 5, 35, and 50°C, respectively. The bearing capacity change can be interpreted through the load-displacement curves. Experiment results were also compared with the solid energy pile to evaluate bearing capacities of the PEP and the solid energy pile under different temperature conditions. The mobilized shaft resistance was also calculated and compared with the solid energy pile data and the results show that the PEP has a similar load transfer mechanism with the solid energy pile. It could also be found that, for PEPs under working load, plastic displacement would appear after a whole heating cycle.

  8. Measurement and Analysis of Horizontal Vibration Response of Pile Foundations

    Directory of Open Access Journals (Sweden)

    A. Boominathan

    2007-01-01

    Full Text Available Pile foundations are frequently used in very loose and weak deposits, in particular soft marine clays deposits to support various industrial structures, power plants, petrochemical complexes, compressor stations and residential multi-storeyed buildings. Under these circumstances, piles are predominantly subjected to horizontal dynamic loads and the pile response to horizontal vibration is very critical due to its low stiffness. Though many analytical methods have been developed to estimate the horizontal vibration response, but they are not well validated with the experimental studies. This paper presents the results of horizontal vibration tests carried out on model aluminium single piles embedded in a simulated Elastic Half Space filled with clay. The influence of various soil and pile parameters such as pile length, modulus of clay, magnitude of dynamic load and frequency of excitation on the horizontal vibration response of single piles was examined. Measurement of various response quantities, such as the load transferred to the pile, pile head displacement and the strain variation along the pile length were done using a Data Acquisition System. It is found that the pile length, modulus of clay and dynamic load, significantly influences the natural frequency and peak amplitude of the soil-pile system. The maximum bending moment occurs at the fundamental frequency of the soil-pile system. The maximum bending moment of long piles is about 2 to 4 times higher than that of short piles and it increases drastically with the increase in the shear modulus of clay for both short and long piles. The active or effective pile length is found to be increasing under dynamic load and empirical equations are proposed to estimate the active pile length under dynamic loads.

  9. Underwater Sound Propagation from Marine Pile Driving.

    Science.gov (United States)

    Reyff, James A

    2016-01-01

    Pile driving occurs in a variety of nearshore environments that typically have very shallow-water depths. The propagation of pile-driving sound in water is complex, where sound is directly radiated from the pile as well as through the ground substrate. Piles driven in the ground near water bodies can produce considerable underwater sound energy. This paper presents examples of sound propagation through shallow-water environments. Some of these examples illustrate the substantial variation in sound amplitude over time that can be critical to understand when computing an acoustic-based safety zone for aquatic species.

  10. 29 CFR 1926.603 - Pile driving equipment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Pile driving equipment. 1926.603 Section 1926.603 Labor... Operations § 1926.603 Pile driving equipment. (a) General requirements. (1) Boilers and piping systems which are a part of, or used with, pile driving equipment shall meet the applicable requirements of the...

  11. Analysis of transients in the SRP test pile

    International Nuclear Information System (INIS)

    Church, J.P.

    1976-11-01

    Analysis of the hypothetical upper limit accident in the Savannah River Test Pile showed that the offsite thyroid dose from fission product release would be -3 of the 10-CFR-100 guideline dose for 95 percent of measured meteorological conditions. Offsite whole body dose would be negligible. The Test Pile was modified to limit the length of test piece that can be charged to the pile. These modifications reduce the potential offsite dose to -5 of the regulatory guidelines. Assessment of Test Pile safety included calculations of transients initiated by a variety of reactivity additions that were either terminated or not terminated by safety systems. Reactivity addition mechanisms considered were abnormally driving control rods out of the pile and charging abnormal test pieces into the pile. The transients were evaluated in the adiabatic approximation in which three-dimensional calculations of static flux shapes and reactivity were superimposed on point reactor kinetics calculations. Negative reactivity feedback effects appropriate for the pile and the temperature dependence of material properties, such as specific heat and thermal conductivity, were included. The results show that, for the worst initiators, safety systems can prevent the temperature rise from exceeding 1 0 C anywhere in the Test Pile. If the safety systems do not function, the pile temperatures will increase until the transient is ended by the inherent negative reactivity effects, including the melting of some fuel

  12. New trends in pile safety instrumentation

    International Nuclear Information System (INIS)

    Furet, J.

    1961-01-01

    This report addresses the protection of nuclear piles against damages due to operation incidents. The author discusses the current trends in the philosophy of safety of atomic power piles, identifies the parameters which define safety systems, presents tests to be performed on safety chains, comments the relationship between safety and the decrease of the number of pile inadvertent shutdowns, discusses the issues of instrument failures and chain multiplicity, comments the possible improvement of the operation of elements which build up safety chains (design simplification, development of semiconductors, replacement of electromechanical relays by static relays), the role of safety logical computers and the development of automatics in pile safety, presents automatic control as a safety factor (example of automatic start-up), and finally comments the use of fuses

  13. Part 1: Logging residues in piles - Needle loss and fuel quality. Part 2: Nitrogen leaching under piles of logging residues

    International Nuclear Information System (INIS)

    Lehtikangas, P.; Lundkvist, H.

    1991-01-01

    Part 1: Experimental piles were built in three geographical locations during May-Sept. 1989. Logging residues consisted of 95% spruce and 5% pine. Height of the piles varied between 80 and 230 cm. Needles were collected by placing drawers under 40 randomely chosen piles. The drawers were emptied every two weeks during the storage period. Natural needle loss was between 18 and 32% of the total amount of needles after the first two months of storage. At the end of the storage period, 24-42% of the needles had fallen down to the drawers. At the end of the experiment the total needle fall was 95-100% in the shaken piles. According to the results of this study piles smaller than 150 cm had the most effective needle fall. Piles should be placed on open places where the air and sun heat penetrate and dry them. Needles were the most sensitive fraction to variations in precipitation compared to the other components, such as branches. Piles usually dried quickly, but they also rewet easily. This was especially true in the smaller piles. The lowest moisture content was measured at the end of June. The ash content in needles varied between 4 and 8%. 16 refs., 15 figs. Part 2: Three field experiments were equipped with no-tension humus lysimeters. Pairs of lysimeters with the same humus/field layer vegetation material were placed in pairs, one under a pile of felling residues and another in the open clear felling. Leaching of nitrogen as well as pH and electric conductivity in the leachate was followed through sampling of the leachate at regular intervals. The results from the investigation show that: * the amount of leachate was higher in lysimeters in the open clear felling, * pH in the leachate was initially lower under piles of felling residues, * the amount of nitrogen leached was higher in the open clear felling. Thus, storing of felling residues in piles during the summer season did not cause any increase in nitrogen leaching, which had been considered to be a risk

  14. The Tensile Capacity Of Bored Piles In Frictional Soils

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Andersen, Allan; Damkilde, Lars

    2008-01-01

    Three series of 10 piles each were installed in two different locations. The length of the piles varied from 2 to 6 m and the diameters were 14 and 25 cm. The piles were constructed above the groundwater table using continuous flight augers and the concrete was placed by gravity free fall. The pi....... The piles were tested to failure in axial uplift and the load-displacement relations were recorded.......Three series of 10 piles each were installed in two different locations. The length of the piles varied from 2 to 6 m and the diameters were 14 and 25 cm. The piles were constructed above the groundwater table using continuous flight augers and the concrete was placed by gravity free fall...

  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. Sheet-gravel evidence for a late Holocene tsunami run-up on beach dunes, Great Barrier Island, New Zealand

    Science.gov (United States)

    Nichol, Scott L.; Lian, Olav B.; Carter, Charles H.

    2003-01-01

    A semi-continuous sheet of granule to cobble-size clasts forms a distinctive deposit on sand dunes located on a coastal barrier in Whangapoua Bay, Great Barrier Island, New Zealand. The gravel sheet extends from the toe of the foredune to 14.3 m above mean sea level and 200 m landward from the beach. Clasts are rounded to sub-rounded and comprise lithologies consistent with local bedrock. Terrestrial sources for the gravel are considered highly unlikely due to the isolation of the dunes from hillslopes and streams. The only source for the clasts is the nearshore to inner shelf of Whangapoua Bay, where gravel sediments have been previously documented. The mechanism for transport of the gravel is unlikely to be storm surge due to the elevation of the deposit; maximum-recorded storm surge on this coast is 0.8 m above mean high water spring tide. Aeolian processes are also discounted due to the size of clasts and the elevation at which they occur. Tsunami is therefore considered the most probable mechanism for gravel transport. Minimum run-up height of the tsunami was 14.3 m, based on maximum elevation of gravel deposits. Optical ages on dune sands beneath and covering the gravel allow age bracketing to 0-4.7 ka. Within this time frame, numerous documented regional seismic and volcanic events could have generated the tsunami, notably submarine volcanism along the southern Kermadec arc to the east-southeast of Great Barrier Island where large magnitude events are documented for the late Holocene. Radiocarbon ages on shell from Maori middens that appear to have been reworked by tsunami run-up constrain the age of this event to post ca. 1400 AD. Regardless of the precise age of this event, the well-preserved nature of the Whangapoua gravel deposit provides for an improved understanding of the high degree of spatial variability in tsunami run-up.

  17. Temperature response functions (G-functions) for single pile heat exchangers

    International Nuclear Information System (INIS)

    Loveridge, Fleur; Powrie, William

    2013-01-01

    Foundation piles used as heat exchangers as part of a ground energy system have the potential to reduce energy use and carbon dioxide emissions from new buildings. However, current design approaches for pile heat exchangers are based on methods developed for boreholes which have a different geometry, with a much larger aspect (length to diameter) ratio. Current methods also neglect the transient behaviour of the pile concrete, instead assuming a steady state resistance for design purposes. As piles have a much larger volume of concrete than boreholes, this neglects the significant potential for heat storage within the pile. To overcome these shortcomings this paper presents new pile temperature response functions (G-functions) which are designed to reflect typical geometries of pile heat exchangers and include the transient response of the pile concrete. Owing to the larger number of pile sizes and pipe configurations which are possible with pile heat exchangers it is not feasible to developed a single unified G-function and instead upper and lower bound solutions are provided for different aspects ratios. - Highlights: • We present new temperature response functions for pile heat exchangers. • The functions include transient heat transfer within the pile concrete. • Application of the functions reduces the resulting calculated temperature ranges. • Greater energy efficiency is possible by accounting for heat storage in the pile

  18. Adhesion, resistivity and structural, optical properties of molybdenum on steel sheet coated with barrier layer done by sol–gel for CIGS solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Amouzou, Dodji, E-mail: dodji.amouzou@fundp.ac.be [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles 61, 5000 Namur (Belgium); Dumont, Jacques [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles 61, 5000 Namur (Belgium); Fourdrinier, Lionel; Richir, Jean-Baptiste; Maseri, Fabrizio [CRM-Group, Boulevard de Colonster, B 57, 4000 Liège (Belgium); Sporken, Robert [Research Centre in Physics of Matter and Radiation (PMR), University of Namur (FUNDP), Rue de Bruxelles 61, 5000 Namur (Belgium)

    2013-03-01

    Molybdenum films are investigated on stainless steel substrates coated with polysilazane based sol–gel and SiO{sub x} layers for flexible CIGS solar cell applications. Thermal stability of the multilayer has been studied. The thickness of polysilazane films are significantly reduced (17%) after heat treatment suggesting a thermal degradation. Four different microstructures were found for Mo films by varying argon total pressure from 2.6 × 10{sup −1} Pa to 2.6 Pa. It was shown that continuous films, low sheet resistance (0.5 Ω/□) and well facetted grains can be achieved when Mo films are deposited on heated substrates at homologous temperature, T of 0.2. - Highlights: ► Steel sheet is functionalized for Cu[Inx,Ga(1 − x)Se2] solar cells. ► Varying deposition pressure impacts the microstructure of Mo films. ► High thermal stability of the sol gel based barrier layer has been investigated. ► Low sheet resistance and continuous Mo films have been obtained at 550°C. ► Thermal stability of functionalized steel sheets at 550°C has been investigated.

  19. Prediction of pile set-up for Ohio soils.

    Science.gov (United States)

    2011-02-01

    ODOT typically uses small diameter driven pipe piles for bridge foundations. When a pile is driven into the subsurface, it disturbs and displaces the soil. As the soil surrounding the pile recovers from the installation disturbance, a time dependant ...

  20. Installation effects of auger cast-in-place piles

    Directory of Open Access Journals (Sweden)

    Fathi M. Abdrabbo

    2012-12-01

    Full Text Available Since their introduction in Europe and North America some 50 years ago, auger cast-in-place piles (ACIP have become increasingly popular all over the world. These piles offer considerable environmental advantages during construction including minimal vibration, and low noise beside their high productivity. The most severe limitation of the ACIP is its sensitivity to operator performance, which can lead to a pile of poor integrity or inconsistent quality. Thus the improper use of ACIP equipment can result in piles containing defects or can cause instability of nearby structures. Three case studies are presented and discussed in an effort to illustrate learned lessons. First case study highlights the misuse of ACIP equipment leading to unreliable defective pile foundations. Second and third case studies show the adverse effects of installing ACIP on the stability of nearby structures. The study revealed that it is essential to employ a clever pile crew during the installation of ACIP to observe, interpret, and take corrective actions for unusual situations. The authorities worldwide should oblige pile contractors to employ only experienced and qualified workers in charge of geotechnical engineering works. Tender documents should include precise clauses related to the technological factors affecting the quality of ACIP. Unfavorable side effects of installing ACIP in saturated loose and medium sand can cause tilt of adjacent existing structures; even they are on either shallow or deep foundations. A row of micro-piles and/or soil grouting adjacent to the existing buildings were successfully used to reduce the adverse effects of ACIP. Implementation of different codes on the results of pile loading tests produced different pile working loads. Therefore tender documents should specify the code upon which interpreting the pile test results. At the meantime the geotechnical engineer should implement his experience and judgment during application of the

  1. The Effects of Time on Soil Behaviour and Pile Capacity

    DEFF Research Database (Denmark)

    Augustesen, Anders

    When designing pile foundations, static design equations, pile driving formulae, static loading tests or stress wave analyses can be employed to estimate the axial capacity of single piles. Both laboratory and field tests show that soil exhibits time-dependent behaviour. An important result...... based on a set of static loading tests. In the literature it is suggested that the pile capacity increases with the logarithm to time after installation which is confirmed in this thesis. In continuation of this, it is analysed whether the magnitude of the set-up is related to the properties of the clay...... circumstances (e.g. load specifications, length of pile, pile material). In order to evaluate the design methods for piles in clay, it is necessary to correct for time between pile driving and pile testing. Results of testing the calculation procedures against the available data by employing different time...

  2. 30 CFR 816.83 - Coal mine waste: Refuse piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal mine waste: Refuse piles. 816.83 Section... ACTIVITIES § 816.83 Coal mine waste: Refuse piles. Refuse piles shall meet the requirements of § 816.81, the... drainage may not be diverted over the outslope of the refuse piles. Runoff from the areas above the refuse...

  3. Numerical Simulation for the Soil-Pile-Structure Interaction under Seismic Loading

    Directory of Open Access Journals (Sweden)

    Lifeng Luan

    2015-01-01

    Full Text Available Piles are widely used as reinforcement structures in geotechnical engineering designs. If the settlement of the soil is greater than the pile, the pile is pulled down by the soil, and negative friction force is produced. Previous studies have mainly focused on the interaction of pile-soil under static condition. However, many pile projects are located in earthquake-prone areas, which indicate the importance of determining the response of the pile-soil structure under seismic load. In this paper, the nonlinear, explicit, and finite difference program FLAC3D, which considers the mechanical behavior of soil-pile interaction, is used to establish an underconsolidated soil-pile mode. The response processes of the pile side friction force, the pile axial force, and the soil response under seismic load are also analyzed.

  4. Interacting with piles of artifacts on digital tables

    NARCIS (Netherlands)

    Aliakseyeu, D.; Lucero Vera, A.A.; Subramanian, S.

    2007-01-01

    Designers and architects regularly use piles to organise visual artifacts. Recent efforts have now made it possible for users to create piles in digital systems as well. However, there is still little understanding of how users shouldinteract with digital piles. In this paper we investigate this

  5. Interacting with piles of artifacts on digital tables

    NARCIS (Netherlands)

    Aliakseyeu, D.; Subramanian, S.; Lucero Vera, A.A.; Gutwin, C.

    2006-01-01

    Designers and architects regularly use piles to organize visual artifacts. Recent efforts have now made it possible for users to create piles in digital systems as well. However, there is still little understanding of how users should interact with digital piles. In this paper we investigate this

  6. FIELD INVESTIGATIONS OF PILED-RAFT FOUNDATIONS WITH SHORT-LENGTH CONIC PILES IN BUILDING AREAS OF MINSK

    Directory of Open Access Journals (Sweden)

    V. A. Sernov

    2015-01-01

    Full Text Available In recent time piled foundations are extensively applied due to an increase of storeys in buildings constructed in Minsk and load increment on the soil. Preference is given to this approach even in the case when relatively firm soil occurs in the top part of the foundation bed. In this case maximum usage of the foundation bed bearing capacity and reduction of foundation cost are considered as top-priority tasks for designers. One of the ways to increase the bearing capacity of piled foundations is the necessity to take into account resistance of foundation bed soil located under raft bottom. The raft as well as a shallow foundation is capable to transfer a significant part of building load into the soil. Such approach makes it possible to reduce a number of piles in the foundation or shorten their length. Then it results in shortening of the construction period and significant reduction in zero cycle. However up to the present moment reliable calculation methods that permit to take into account soil resistance in the raft base. An analysis of previous investigations on the matter executed by various researchers and a number of field investigations have been carried out with the purpose to develop the proposed methods.The paper presents results of field investigations on foundations consisting of short stamped tapered piles which are joined together with the help of the raft fragment. Strength and deformation characteristics of the bases are increasing while making such foundations in the fill-up soil. In this case the filled-up ground layer becomes a bearing layer both for piles and rafts as well. Improvement of high-plastic clay-bearing soil properties is ensured by ramming dry concrete mix under pile foot. The paper describes an experience on application of the piled-raft foundation in complicated engineering and geological conditions while constructing the Orthodox Church in Minsk.

  7. 30 CFR 77.215-1 - Refuse piles; identification.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; identification. 77.215-1 Section... COAL MINES Surface Installations § 77.215-1 Refuse piles; identification. A permanent identification marker, at least six feet high and showing the refuse pile identification number as assigned by the...

  8. Concentration processes under tubesheet sludge piles in nuclear steam generators

    International Nuclear Information System (INIS)

    Gonzalez, F.; Spekkens, P.

    1987-01-01

    The process by which bulk water solutes are concentrated under tubesheet sludge piles in nuclear steam generators was investigated in the laboratory under simulated CANDU operating conditions. Concentration rates were found to depend on the tube heat flux and pile depth, although beyond a critical depth the concentration efficiency decreased. This efficiency could be expressed by a concentration coefficient, and was found to depend also on the sludge pile porosity. Solute concentration profiles in the sludge pile suggested that the concentration mechanism in a high-porosity/permeability pile is characterized by boiling mainly near or at the tube surface, while in low-porosity piles, the change of phase may also become important in the body of the sludge pile. In all cases, the full depth of the pile was active to some extent in the concentration process. As long as the heat transfer under the pile was continued, the solute remained under the pile and slowly migrated toward the bottom. When the heat transfer was stopped, the solute diffused back into the bulk solution at a rate slower than that of the concentration process

  9. Review of vibration effect during piling installation to adjacent structure

    Science.gov (United States)

    Rahman, Nurul Aishah Abd; Musir, Adhilla Ainun; Dahalan, Nurol Huda; Ghani, Abdul Naser Abdul; Khalil, Muhamad Kasimi Abd

    2017-12-01

    Basically, many major structures across the world such as towers, high rise building, houses and bridges utilize pile as a support material. The use of pile is important to strengthen the structures. However, this has led to another problem to the nearest surrounding structures resulted from pile driving. As part of a construction work, unavoidable pile driving activity generates a vibration towards the surrounding structures if uncontrolled may cause damage to the adjacent structure. As the current construction works are frequently located in urban areas where the distance between the nearest building structures is not far, vibration may cause damage to nearby structures. Knowing which part of the building that is mostly affected by various vibration patterns from the impact of pile driving is crucial. Thus, it is very important to predict the impact of vibration during piling installation work. This paper reviews the vibrations generated by piling activity toward surrounding structures in terms sources of vibration, impact of piling installation, pile-soil interaction, and factors affecting the vibration impact of building as well as to study the parameters involved in vibration generation during piling works.

  10. 30 CFR 77.215-3 - Refuse piles: certification.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles: certification. 77.215-3 Section... COAL MINES Surface Installations § 77.215-3 Refuse piles: certification. (a) Within 180 days following written notification by the District Manager that a refuse pile can present a hazard, the person owning...

  11. Interesting Developments in Testing Methods Applied to Foundation Piles

    Science.gov (United States)

    Sobala, Dariusz; Tkaczyński, Grzegorz

    2017-10-01

    Both: piling technologies and pile testing methods are a subject of current development. New technologies, providing larger diameters or using in-situ materials, are very demanding in terms of providing proper quality of execution of works. That concerns the material quality and continuity which define the integral strength of pile. On the other side we have the capacity of the ground around the pile and its ability to carry the loads transferred by shaft and pile base. Inhomogeneous nature of soils and a relatively small amount of tested piles imposes very good understanding of small amount of results. In some special cases the capacity test itself form an important cost in the piling contract. This work presents a brief description of selected testing methods and authors remarks based on cooperation with Universities constantly developing new ideas. Paper presents some experience based remarks on integrity testing by means of low energy impact (low strain) and introduces selected (Polish) developments in the field of closed-end pipe piles testing based on bi-directional loading, similar to Osterberg idea, but without sacrificial hydraulic jack. Such test is suitable especially when steel piles are used for temporary support in the rivers, where constructing of conventional testing appliance with anchor piles or kentledge meets technical problems. According to the author’s experience, such tests were not yet used on the building site but they bring a real potential especially, when the displacement control can be provided from the river bank using surveying techniques.

  12. Laboratory Test Setup for Cyclic Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

    2017-01-01

    This paper presents a comprehensive description and the considerations regarding the design of a new laboratory test setup for testing cyclic axially loaded piles in sand. The test setup aims at analysing the effect of axial one-way cyclic loading on pile capacity and accumulated displacements....... Another aim was to test a large diameter pile segment with dimensions resembling full-scale piles to model the interface properties between pile and sand correctly. The pile segment was an open-ended steel pipe pile with a diameter of 0.5 m and a length of 1 m. The sand conditions resembled the dense sand...... determined from the API RP 2GEO standard and from the test results indicated over consolidation of the sand. Two initial one-way cyclic loading tests provided results of effects on pile capacity and accumulated displacements in agreement with other researchers’ test results....

  13. 30 CFR 77.215 - Refuse piles; construction requirements.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; construction requirements. 77.215... COAL MINES Surface Installations § 77.215 Refuse piles; construction requirements. (a) Refuse deposited on a pile shall be spread in layers and compacted in such a manner so as to minimize the flow of air...

  14. Friction effects on lateral loading behavior of rigid piles

    DEFF Research Database (Denmark)

    Zania, Varvara; Hededal, Ole

    2012-01-01

    taking into account the shear frictional resistance along the pile. For this purpose efficient three dimensional finite element models of different diameter have been developed. The increase of the side friction and of the diameter of the pile is shown to alter the failure pattern and increase...... the lateral capacity of the pile. The obtained p - y curves demonstrate the importance of the aforementioned parameters in the design of rigid piles, as the reduction of friction along the interface reduces not only the ultimate load but also the stiffness of the soil-pile response. Read More: http...

  15. Numerical Analysis of Helical Pile-Soil Interaction under Compressive Loads

    Science.gov (United States)

    Polishchuk, A. I.; Maksimov, F. A.

    2017-11-01

    The results of the field tests of full-scale steel helical piles in clay soils intended for prefabricated temporary buildings foundations are presented in this article. The finite element modeling was used for the evaluation of stress distribution of the clay soil around helical piles. An approach of modeling of the screw-pile geometry has been proposed through the Finite Element Analysis. Steel helical piles with a length of 2.0 m, shaft diameter of 0.108 m and a blade diameter of 0.3 m were used in the experiments. The experiments have shown the efficiency of double-bladed helical piles in the clay soils compared to single-bladed piles. It has been experimentally established that the introduction of the second blade into the pile shaft provides an increase of the bearing capacity in clay soil up to 30% compared to a single-bladed helical pile with similar geometrical dimensions. The numerical results are compared with the measurements obtained by a large scale test and the bearing capacity has been estimated. It has been found that the model results fit the field results. For a double-bladed helical pile it was revealed that shear stresses upon pile loading are formed along the lateral surface forming a cylindrical failure surface.

  16. Analytical out-of-pile and in-pile experiments on gadolinia bearing fuels

    International Nuclear Information System (INIS)

    Bruet, M.; Francois, B.; Do, Q.; Bergeron, J.; Trotabas, M.

    1986-06-01

    New fuel management schemes in PWRs can be achieved through the use of burnable poisons like gadolinia bearing fuel rods. However, the introduction of such a design has required a qualification program, which has been performed in collaboration between CEA, FRAGEMA and/or FRAMATOME by specialized teams in CEA facilities. The main scoops of this program concern: the fabrication process; the out of pile physical properties determination: the in pile thermomechanical behaviour and fission product release; the neutronic studies in view to validate the Computed Gd efficiency and the LBP depletion calculation schemes and to analyse and assess various schemes of core calculations

  17. FORECASTING PILE SETTLEMENT ON CLAYSTONE USING NUMERICAL AND ANALYTICAL METHODS

    Directory of Open Access Journals (Sweden)

    Ponomarev Andrey Budimirovich

    2016-06-01

    Full Text Available In the article the problem of designing pile foundations on claystones is reviewed. The purpose of this paper is comparative analysis of the analytical and numerical methods for forecasting the settlement of piles on claystones. The following tasks were solved during the study: 1 The existing researches of pile settlement are analyzed; 2 The characteristics of experimental studies and the parameters for numerical modeling are presented, methods of field research of single piles’ operation are described; 3 Calculation of single pile settlement is performed using numerical methods in the software package Plaxis 2D and analytical method according to the requirements SP 24.13330.2011; 4 Experimental data is compared with the results of analytical and numerical calculations; 5 Basing on these results recommendations for forecasting pile settlement on claystone are presented. Much attention is paid to the calculation of pile settlement considering the impacted areas in ground space beside pile and the comparison with the results of field experiments. Basing on the obtained results, for the prediction of settlement of single pile on claystone the authors recommend using the analytical method considered in SP 24.13330.2011 with account for the impacted areas in ground space beside driven pile. In the case of forecasting the settlement of single pile on claystone by numerical methods in Plaxis 2D the authors recommend using the Hardening Soil model considering the impacted areas in ground space beside the driven pile. The analyses of the results and calculations are presented for examination and verification; therefore it is necessary to continue the research work of deep foundation at another experimental sites to improve the reliability of the calculation of pile foundation settlement. The work is of great interest for geotechnical engineers engaged in research, design and construction of pile foundations.

  18. Global and local scour at pile groups

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Bundgaard, Klavs; Fredsøe, Jørgen

    2005-01-01

    This paper presents the results of an experimental investigation on scour around pile groups with different configurations exposed to steady current. Two kinds of tests were carried out: rigid-bed tests and actual scour tests. In these, the mean and turbulence properties of the flow were measured...... across the pile groups. The pile-group configurations were such that the global scour was distinguished from the local scour. The results show that the global scour can be quite substantial....

  19. Uranium absorption study pile

    International Nuclear Information System (INIS)

    Raievski, V.; Sautiez, B.

    1959-01-01

    The report describes a pile designed to measure the absorption of fuel slugs. The pile is of graphite and comprises a central section composed of uranium rods in a regular lattice. RaBe sources and BF 3 counters are situated on either side of the center. A given uranium charge is compared with a specimen charge of about 560 kg, and the difference in absorption between the two noted. The sensitivity of the equipment will detect absorption variations of about a few ppm boron (10 -6 boron per gr. of uranium) or better. (author) [fr

  20. Three dimensional modeling of laterally loaded pile groups resting in sand

    Directory of Open Access Journals (Sweden)

    Amr Farouk Elhakim

    2016-04-01

    Full Text Available Many structures often carry lateral loads due to earth pressure, wind, earthquakes, wave action and ship impact. The accurate predictions of the load–displacement response of the pile group as well as the straining actions are needed for a safe and economic design. Most research focused on the behavior of laterally loaded single piles though piles are most frequently used in groups. Soil is modeled as an elastic-perfectly plastic model using the Mohr–Coulomb constitutive model. The three-dimensional Plaxis model is validated using load–displacement results from centrifuge tests of laterally loaded piles embedded in sand. This study utilizes three dimensional finite element modeling to better understand the main parameters that affect the response of laterally loaded pile groups (2 × 2 and 3 × 3 pile configurations including sand relative density, pile spacing (s = 2.5 D, 5 D and 8 D and pile location within the group. The fixity of the pile head affects its load–displacement under lateral loading. Typically, the pile head may be unrestrained (free head as the pile head is allowed to rotate, or restrained (fixed head condition where no pile head rotation is permitted. The analyses were performed for both free and fixed head conditions.

  1. Skin barrier composition

    International Nuclear Information System (INIS)

    Osburn, F.G.

    1985-01-01

    A skin barrier composition comprises a mixture of a copolymer resin of ethylene and vinyl acetate (EVA), and a water-insoluble dry tack-providing elastomer such as polyisobutylene. The composition after mixing and molding, is subjected to ionizing irradiation to form cross-linked polymer networks of the EVA. The compositions have exceptional properties for use as barrier sheets, rings, or strips in ostomy, wound drainage, and incontinence devices. (author)

  2. Skin barrier composition

    Energy Technology Data Exchange (ETDEWEB)

    Osburn, F G

    1985-06-12

    A skin barrier composition comprises a mixture of a copolymer resin of ethylene and vinyl acetate (EVA), and a water-insoluble dry tack-providing elastomer such as polyisobutylene. The composition after mixing and molding, is subjected to ionizing irradiation to form cross-linked polymer networks of the EVA. The compositions have exceptional properties for use as barrier sheets, rings, or strips in ostomy, wound drainage, and incontinence devices.

  3. Three dimensional analysis of laterally loaded piles

    International Nuclear Information System (INIS)

    Yilmaz, C.

    1987-01-01

    In this study static analysis of laterally loaded pile is studied by the three models. The first model is the beam on discrete elastic springs. This model is analyzed using a flexibility method. The second model is the beam on a two-parameter elastic foundation. This model is analyzed using the linear finite element method. The third model is the finite element model, using the three-dimensional iso-parametric parabolic brick element. Three-dimensional pile group analysis is also performed using elastic constants of single pile obtained by any one of the above analyses. The main objective is to develop computer programs for each model related to single piles and to group analysis. Then, the deflections, rotations, moments, shears, stresses and strains of the single pile are obtained at any arbitrary point. Comparison is made between each model and with other studies such as Poulos 1971, Desai and Appel 1976. In addition, to provide a benchmark of three-dimensional finite element analysis, the Boussinesq problem is analyzed. (orig.)

  4. Foundation heat transfer analysis for buildings with thermal piles

    International Nuclear Information System (INIS)

    Almanza Huerta, Luis Enrique; Krarti, Moncef

    2015-01-01

    Highlights: • A numerical transient thermal model for thermo-active foundations is developed. • Thermal interactions between thermal piles and building foundations are evaluated. • A simplified analysis method of thermal interactions between thermal piles and building foundations is developed. - Abstract: Thermal piles or thermo-active foundations utilize heat exchangers embedded within foundation footings to heat and/or cool buildings. In this paper, the impact of thermal piles on building foundation heat transfer is investigated. In particular, a simplified analysis method is developed to estimate the annual ground-coupled foundation heat transfer when buildings are equipped with thermal piles. First, a numerical analysis of the thermal performance of thermo-active building foundations is developed and used to assess the interactions between thermal piles and slab-on-grade building foundations. The impact of various design parameters and operating conditions is evaluated including foundation pile depth, building slab width, foundation insulation configuration, and soil thermal properties. Based on the results of a series of parametric analyses, a simplified analysis method is presented to assess the impact of the thermal piles on the annual heat fluxes toward or from the building foundations. A comparative evaluation of the predictions of the simplified analysis method and those obtained from the detailed numerical analysis indicated good agreement with prediction accuracy lower than 5%. Moreover, it is found that thermal piles can affect annual building foundation heat loss/gain by up to 30% depending on foundation size and insulation level

  5. 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.

  6. Modeling temperature noise in a fast-reactor pile

    International Nuclear Information System (INIS)

    Kebadze, B.V.; Pykhtina, T.V.; Tarasko, M.Z.

    1987-01-01

    To observe partial overlapping of the heat carrier cross section in piles, leading to local temperature rise or boiling of the sodium, provision is made for individual monitoring of the fuel assemblies with respect to the output temperature. Since the deviation of the mean flow rate through the pile and the output temperature is slight with this anomaly, the temperature fluctuations may provide a more informative index. The change in noise characteristics with partial overlapping of the cross sections occurs because of strong distortion of the temperature profile in the overlap region. The turbulent flow in the upper part of the pile transforms this nonuniformity into temperature pulsations which may be recorded by a sensor at the pile output. In this paper the characteristics of temperature noise are studied for various pile conditions and sensor locations by statistical modeling

  7. Global and local scour at pile groups

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Bundgaard, Klavs; Fredsøe, Jørgen

    2005-01-01

    This paper presents the results of an experimental investigation on scour around pile groups with different configurations exposed to steady current. Two kinds of tests were carried out: (1) Rigid-bed tests, and (2) Actual scour tests. In the former tests, the mean and turbulence properties...... of the flow were measured across the pile groups. The pile group configurations were such that the global scour was distinguished from the local scour. The results show that the global scour can be quite substantial....

  8. Response of shallow geothermal energy pile from laboratory model tests

    Science.gov (United States)

    Marto, A.; Amaludin, A.

    2015-09-01

    In shallow geothermal energy pile systems, the thermal loads from the pile, transferred and stored in the soil will cause thermally induced settlement. This factor must be considered in the geotechnical design process to avoid unexpected hazards. Series of laboratory model tests were carried out to study the behaviour of energy piles installed in kaolin soil, subjected to thermal loads and a combination of axial and thermal loads (henceforth known as thermo-axial loads). Six tests which included two thermal load tests (35°C and 40°C) and four thermo-axial load tests (100 N and 200 N, combined with 35°C and 40°C thermal loads) were conducted. To simulate the behaviour of geothermal energy piles during its operation, the thermo-axial tests were carried out by applying an axial load to the model pile head, and a subsequent application of thermal load. The model soil was compacted at 90% maximum dry density and had an undrained shear strength of 37 kPa, thus classified as having a firm soil consistency. The behaviour of model pile, having the ultimate load capacity of 460 N, was monitored using a linear variable displacement transducer, load cell and wire thermocouple, to measure the pile head settlement, applied axial load and model pile temperature. The acquired data from this study was used to define the thermo-axial response characteristics of the energy pile model. In this study, the limiting settlement was defined as 10% of the model pile diameter. For thermal load tests, higher thermal loads induced higher values of thermal settlement. At 40°C thermal load an irreversible settlement was observed after the heating and cooling cycle was applied to the model pile. Meanwhile, the pile response to thermo-axial loads were attributed to soil consistency and the magnitude of both the axial and thermal loads applied to the pile. The higher the thermoaxial loads, the higher the settlements occurred. A slight hazard on the model pile was detected, since the settlement

  9. Heave induced reduction of friction capacity of pile embedded in clays

    OpenAIRE

    Setyo Budi Gogot; Wibowo Tantri Gondo

    2017-01-01

    Installation of new piles may cause heave which influence friction capacity of existing piles. The heave can be observed from the difference in the elevation of existing pile heads recorded before and after the installation of new piles or through load-settlement diagram from Static Load Test data. This paper presents the study of bearing capacity of hollow cylindrical concrete piles with diameter of 800 mm from two projects. The piles at Project I and Project II were hydraulically jacked int...

  10. Estimating volume, biomass, and potential emissions of hand-piled fuels

    Science.gov (United States)

    Clinton S. Wright; Cameron S. Balog; Jeffrey W. Kelly

    2009-01-01

    Dimensions, volume, and biomass were measured for 121 hand-constructed piles composed primarily of coniferous (n = 63) and shrub/hardwood (n = 58) material at sites in Washington and California. Equations using pile dimensions, shape, and type allow users to accurately estimate the biomass of hand piles. Equations for estimating true pile volume from simple geometric...

  11. Influences on the thermal efficiency of energy piles

    International Nuclear Information System (INIS)

    Cecinato, Francesco; Loveridge, Fleur A.

    2015-01-01

    Energy piles have recently emerged as a viable alternative to borehole heat exchangers, but their energy efficiency has so far seen little research. In this work, a finite element numerical model is developed for the accurate 3D analysis of transient diffusive and convective heat exchange phenomena taking place in geothermal structures. The model is validated by reproducing both the outcome of a thermal response test carried out on a test pile, and the average response of the linear heat source analytical solution. Then, the model is employed to carry out a parametric analysis to identify the key factors in maximising the pile energy efficiency. It is shown that the most influential design parameter is the number of pipes, which can be more conveniently increased, within a reasonable range, compared to increasing the pile dimensions. The influence of changing pile length, concrete conductivity, pile diameter and concrete cover are also discussed in light of their energetic implications. Counter to engineering intuition, the fluid flowrate does not emerge as important in energy efficiency, provided it is sufficient to ensure turbulent flow. The model presented in this paper can be easily adapted to the detailed study of other types of geothermal structures. - Highlights: • A numerical model for 3D thermal transient analysis of energy piles is developed. • The model is validated against both field data and an analytical solution. • Key parameters are then identified for efficient thermal design of energy piles. • Energy efficiency is maximised by large pipe number and concrete conductivity. • Large exchanger fluid velocity does not have a major impact on efficiency

  12. Dynamic stiffness of pile groups in a multilayered soil. Part 1

    International Nuclear Information System (INIS)

    Ohta, Y.; Hijikata, K.; Kobayashi, Y.

    1989-01-01

    For evaluating the dynamic stiffness of the pile group foundations, forced vibration tests are executed on pile group foundation models. Two types of test models are used, one is a single pile model and the other a four-pile model. Dividing the tests into 4 steps, the forced vibration tests are performed. Step 1 is for the single pile model, and steps 2 to 4 are for the four-pile model. In step 2 and step 3, the gap effects between the foundation bottom and the ground surface are examined. In step 4, the backfill effects are obtained. Based on the test results, the pile group effects, the gap effects and the backfill effects on the dynamic characteristics of the pile group foundations are described in this paper

  13. Field Test of Driven Pile Group under Lateral Loading

    Science.gov (United States)

    Gorska, Karolina; Rybak, Jaroslaw; Wyjadlowski, Marek

    2017-12-01

    All the geotechnical works need to be tested because the diversity of soil parameters is much higher than in other fields of construction. Horizontal load tests are necessary to determine the lateral capacity of driven piles subject to lateral load. Various load tests were carried out altogether on the test field in Kutno (Poland). While selecting the piles for load tests, different load combinations were taken into account. The piles with diverse length were chosen, on the basis of the previous tests of their length and integrity. The subsoil around the piles consisted of mineral soils: clays and medium compacted sands with the density index ID>0.50. The pile heads were free. The points of support of the “base” to which the dial gauges (displacement sensors) were fastened were located at the distance of 0.7 m from the side surface of the pile loaded laterally. In order to assure the independence of measurement, additional control (verifying) geodetic survey of the displacement of the piles subject to the load tests was carried out (by means of the alignment method). The trial load was imposed in stages by means of a hydraulic jack. The oil pressure in the actuator was corrected by means of a manual pump in order to ensure the constant value of the load in the on-going process of the displacement of the pile under test. On the basis of the obtained results it is possible to verify the numerical simulations of the behaviour of piles loaded by a lateral force.

  14. Characteristics of thermal neutron calibration fields using a graphite pile

    International Nuclear Information System (INIS)

    Uchita, Yoshiaki; Saegusa, Jun; Kajimoto, Yoichi; Tanimura, Yoshihiko; Shimizu, Shigeru; Yoshizawa, Michio

    2005-03-01

    The Facility of Radiation Standards of Japan Atomic Energy Research Institute is equipped with thermal neutron fields for calibrating area and personal neutron dosemeters. The fields use moderated neutrons leaked from a graphite pile in which radionuclide sources are placed. In January 2003, we have renewed the pile with some modifications in its size. In accordance with the renewal, we measured and calculated thermal neutron fluence rates, neutron energy distributions and angular distributions of the fields. The thermal neutron fluence rates of the ''inside-pile fields'' and the outside-pile fields'' were determined by the gold foil activation method. The neutron energy distributions of the outside-pile fields were also measured with the Bonner multi-sphere spectrometer system. The contributions of epithermal and fast neutrons to the total dose-equivalents were 9% in the southern outside-pile field and 12% in the western outside-pile field. The personal dose-equivalents, H p,slab (10, α), in the outside-pile fields are evaluated by considering the calculated angular distributions of incoming neutrons. The H p,slab (10, α) was found to be about 40% higher than the value in assuming the unidirectional neutron between the pile and the test point. (author)

  15. Analysis of radon protection cover on uranium tailings pile

    International Nuclear Information System (INIS)

    Zhang Zhe

    1993-01-01

    The average radon emanation rate of the whole surface over one year was used for evaluating the radon release of uranium tailings pile. The effective of radon protection cover depends on the shape and property of the tailings pile, the properties of covering and the control of air vadose in the pile. It was indicated that the covering with low diffusion coefficient, small porosity and bad permeability was suitable to cover the pile. The analytical formula of the covering layer thickness was given

  16. VELOCITY OF VISCID FLOW LANDSLIDES IN THE EVENT OF A PILE CURTAIN AND A CONTINUOUS RETAINING WALL

    Directory of Open Access Journals (Sweden)

    Buslov Anatoliy Semenovich

    2012-10-01

    The third section, which can be compared with the flow of viscid fluid in a canal, is typical for buttresses that have a significant length in the direction of the landslide flow. The papers hows that the common parameter applicable both to solid and dispersed barriers is the controlled volume of the fluid flow at the point of entry to the pre-boundary area. As a result of application of the proposed methodology, equations were obtained that made it possible to calculate the speed of the viscid slide depending on different types of piles. The paper describes the conditions that make the viscid mass climb over the constructed barrier.

  17. Measurements of pile driving noise from control piles and noise-reduced piles at the Vashon Island ferry dock.

    Science.gov (United States)

    2017-04-01

    As part of the Washington State Department of Transportation (WSDOT) pile attenuation test program, : researchers from the University of Washington Applied Physics Laboratory (APL-UW) conducted underwater sound : measurements on 7 and 8 December 2015...

  18. Experimental Comparison of Statically and Cyclically Loaded Non-Slender Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    rigid form of motion. The Winkler model approach, employing p-y curves to describe the soil-pile interaction, is often employed as the design method for laterally loaded piles. The p-y curve formulation, currently recommended by the American Petroleum Institute and Det Norske Veritas, is based on tests...... on slender piles with length to diameter ratios larger than ten and outer pile diameters less than two meters. Hence, the pile tests that form the basis of the currently recommended p-y curve formulation are conducted with use of piles that exhibits a flexible behaviour, which is in contrast to the piles...... used as foundation for modern offshore wind energy converters. The aim of the present work is to investigate the pile behaviour for non-slender piles by means of small-scale testing. The pile behaviour is investigated and compared for both static and cyclic loading. When conducting small-scale tests...

  19. Theoretical study of short pile effect in tunnel excavation

    Science.gov (United States)

    Tian, Xiao-yan; Liu, Jing; Gao, Xiao-mei; Li, Yuan

    2017-09-01

    The Misaki Sato Go ideal elastoplastic model is adopted and the two stage analysis theory is used to study the effect of tunnel excavation on short pile effect in this paper. In the first stage, the free field vertical displacement of the soil at the corresponding pile location is obtained by using empirical formula. In the second stage, the displacement is applied to the corresponding pile location. The equilibrium condition of micro physical differential equation settlement of piles. Then through logical deduction and the boundary condition expressions of the settlement calculation, obtain the pile side friction resistance and axial force of the week. Finally, an engineering example is used to analyze the influence of the change of main parameters on their effects.

  20. Starting up a programme of atomic piles using compressed gas

    International Nuclear Information System (INIS)

    Horowitz, J.; Yvon, J.

    1959-01-01

    1) An examination of the intellectual and material resources which have directed the French programme towards: a) the natural uranium and plutonium system, b) the use of compressed gas as heat transfer fluid (primary fluid). 2) The parts played in exploring the field by the pile EL2 and G1, EL2 a natural uranium, heavy water and compressed gas pile, G1 a natural uranium, graphite and atmospheric air pile. 3) Development of the neutronics of graphite piles: physical study of G1. 4) The examination of certain problem posed by centres equipped with natural uranium, graphite and compressed carbon dioxide piles: structure, special materials, fluid circuits, maximum efficiency. Economic aspects. 5) Aids to progress: a) piles for testing materials and for tests on canned fuel elements, b) laboratory and calculation facilities. 6) Possible new orientations of compressed gas piles: a) raising of the pressure, b) enriched fuel, c) higher temperatures, d) use of heavy water. (author) [fr

  1. Analysis of static and dynamic pile-soil-jacket behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Azadi, Mohammad Reza Emami

    1998-12-31

    In the offshore industry, recent extreme storms, severe earthquakes and subsidence of the foundation of jacket platforms have shown that new models and methods must take into account the jacket- pile-soil foundation interaction as well as the non-linear dynamic performance/loading effects. This thesis begins with a review of the state of art pile-soil interaction model, recognizing that most existing pile-soil models have been established based on large diameter pile tests on specific sites. The need for site independent and mechanistic pile-soil interaction models led to the development of new (t-z) and (p-y) disk models. These are validated using the available database from recent large diameter pile tests in the North Sea and Gulf of Mexico. The established static disk models are applied for non-linear static analysis of the jacket-pile-soil system under extreme wave loading. Dynamic pile-soil interaction is studied and a new disk-cone model is developed for the non-linear and non-homogeneous soils. This model is applied to both surface and embedded disks in a soil layer with non-linear properties. Simplified non-linear as well as more complex analysis methods are used to study the dynamic response of the jacket platform under extreme sea and seismic loading. Ductility spectra analysis is introduced and used to study the dynamic performance of the jacket systems near collapse. Case studies are used to illustrate the effects of structural, foundation failure characteristics as well as dynamic loading effects on the overall performance of the jacket-pile-soil systems near ultimate collapse. 175 refs., 429 figs., 70 tabs.

  2. THE NEW STRUCTURE OF A PLATE-PILE FOUNDATION

    Directory of Open Access Journals (Sweden)

    SAMORODOV О. V.

    2016-01-01

    Full Text Available Raising of problem. In the construction of high-rise buildings with significant loads on foundations and bedding at the base of not rocky soils tend to use the most common pile foundation to reduce the deformation and correspond to regulations [1] on the maximum permissible deformation. Monitoring of the stress-strain state (SSS pile foundations constructed buildings shows the existing reserves of bearing capacity on the one hand - soil bases of the second group of limit states, on the other - the foundation of the first group of limit states by regulating the SSS foundation during construction and exploitation. Therefore, are increasingly using more progressive structure of foundations consisting of piles and of plate, as well as methods for their construction [2 - 10], however, in their design there are a number of disadvantages associated with the ambiguity of the application of methods for the calculation of such structures, which allows to do only partial conclusions and recommendations. Purpose. Is proposing the new structure of a plate-pile foundation, which overcomes the drawbacks of the existing design solutions and methods of consruction their, as well as is proposing an engineering method of a determination of basic parameters. Conclusion. Is proposes the new structure of a plate-pile foundation and the method of a determination of basic parameters his in the design of a soil base to the maximum permissible deformation Su buildings. Efficiency of application this type plate-pile foundation obtained by rational distribution resistance between a plate and piles, when under load from the building to the first work fully incorporated plate that allows maximum deformed for plate, and then the piles - due to of the hinge connection with the plate. Thus, depending on the maximum permissible deformation for buildings resistance of plate part of a full load of more than 50%, that significantly reduces the consumption of concrete.

  3. Pile-up correction by Genetic Algorithm and Artificial Neural Network

    Science.gov (United States)

    Kafaee, M.; Saramad, S.

    2009-08-01

    Pile-up distortion is a common problem for high counting rates radiation spectroscopy in many fields such as industrial, nuclear and medical applications. It is possible to reduce pulse pile-up using hardware-based pile-up rejections. However, this phenomenon may not be eliminated completely by this approach and the spectrum distortion caused by pile-up rejection can be increased as well. In addition, inaccurate correction or rejection of pile-up artifacts in applications such as energy dispersive X-ray (EDX) spectrometers can lead to losses of counts, will give poor quantitative results and even false element identification. Therefore, it is highly desirable to use software-based models to predict and correct any recognized pile-up signals in data acquisition systems. The present paper describes two new intelligent approaches for pile-up correction; the Genetic Algorithm (GA) and Artificial Neural Networks (ANNs). The validation and testing results of these new methods have been compared, which shows excellent agreement with the measured data with 60Co source and NaI detector. The Monte Carlo simulation of these new intelligent algorithms also shows their advantages over hardware-based pulse pile-up rejection methods.

  4. 40 CFR 761.347 - First level sampling-waste from existing piles.

    Science.gov (United States)

    2010-07-01

    ... existing piles. 761.347 Section 761.347 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... from existing piles. (a) General. Sample piles that are either specifically configured for sampling... alternate sampling plan in accordance with § 761.62(c). (b) Specifically configured piles. A specifically...

  5. 30 CFR 77.215-2 - Refuse piles; reporting requirements.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Refuse piles; reporting requirements. 77.215-2... COAL MINES Surface Installations § 77.215-2 Refuse piles; reporting requirements. (a) The proposed location of a new refuse pile shall be reported to and acknowledged in writing by the District Manager...

  6. The Settlement Behavior of Piled Raft Interaction in Undrained Soil

    DEFF Research Database (Denmark)

    Ghalesari, Abbasali Taghavi; Barari, Amin; Amini, Pedram Fardad

    2013-01-01

    Offshore piled raft foundations are one of the most commonly used foundations in offshore structures. When a raft foundation alone does not satisfy the design requirements, the addition of piles may improve both the ultimate load capacity and the settlement performance of the raft. In this paper......, the behavior of a piled raft on undrained soil is studied based on a series of parametric studies on the average and differential settlement of piled raft using three-dimensional finite element analysis. The settlement behavior is found to be dependent on the number of piles and raft thickness....

  7. Vibration tests on pile-group foundations using large-scale blast excitation

    International Nuclear Information System (INIS)

    Tanaka, Hideo; Hijikata, Katsuichirou; Hashimoto, Takayuki; Fujiwara, Kazushige; Kontani, Osamu; Miyamoto, Yuji; Suzuki, Atsushi

    2005-01-01

    Extensive vibration tests have been performed on pile-supported structures at a large-scale mining site. Ground motions induced by large-scale blasting operations were used as excitation forces for vibration tests. The main objective of this research is to investigate the dynamic behavior of pile-supported structures, in particular, pile-group effects. Two test structures were constructed in an excavated 4 m deep pit. One structure had 25 steel tubular piles and the other had 4 piles. The super-structures were exactly the same. The test pit was backfilled with sand of appropriate grain size distributions in order to obtain good compaction, especially between the 25 piles. Accelerations were measured at the structures, in the test pit and in the adjacent free field, and pile strains were measured. The vibration tests were performed six times with different levels of input motions. The maximum horizontal acceleration recorded at the adjacent ground surface varied from 57 cm/s 2 to 1683 cm/s 2 according to the distances between the test site and the blast areas. Maximum strains were 13,400 micro-strains were recorded at the pile top of the 4-pile structure, which means that these piles were subjected to yielding

  8. Ultimate capacity of piles penetrating in weak soil layers

    Directory of Open Access Journals (Sweden)

    Al-Obaidi Ahmed

    2018-01-01

    Full Text Available A pile foundation is one of the most popular forms of deep foundations. They are routinely employed to transfer axial structure loads through the soft soil to stronger bearing strata. Piles generally used to increase the load carrying capacity of the foundation and reduce the settlement of the foundation. On the other hand, many cases in practice where piles pass through different layers of soil that contain weak layers located at different depths and extension, also some time cavities with a different shape, size, and depth are found. In this study, a total of 96 cases is considered and simulated in PLAXIS 2D program aiming to understand the influence of weak soil on the ultimate pile capacity. The piles embedded in the dense sand with a layer of weak soil at different extension and location. The cross section of the geometry used in this study was designed as an axisymmetric model with the 15-node element; the boundary condition recommended at least 5D in the horizontal direction, and (L+5D in the vertical direction where D and L are the diameter and length of pile, respectively. The soil is modeled as Mohr-Coulomb, with five input parameters and the behavior of pile material represented by the linear elastic model. The results of the above cases are compared with the results found in a pile embedded in dense soil without weak layers or cavities. The results indicated that the existence of weak soil layer within the surrounding soil around the pile decreases the ultimate capacity. Furthermore, it has been found that increase in the weak soil width (extension leads to reduction in the ultimate capacity of the pile. This phenomenon is applicable to all depth of weak soil. The influence of weak layer extension on the ultimate capacity is less when it is presentin the upper soil layers.

  9. Program of in-pile IASCC testing under the simulated actual plant condition. Development of technique for in-pile IASCC initiation test in JMTR

    International Nuclear Information System (INIS)

    Ugachi, Hirokazu; Tsukada, Takashi; Kaji, Yoshiyuki; Nagata, Nobuaki; Dozaki, Koji; Takiguchi, Hideki

    2003-01-01

    Irradiation assisted stress corrosion cracking (IASCC) is caused by the synergistic effects of neutron irradiation, stress and corrosion by high temperature water. It is, therefore, essential to perform in-pile SCC tests, which are material tests under the conditions simulating those of actual LWR operation, in order to clarify the precise mechanism of the phenomenon, though mainly out-of-pile SCC tests for irradiated materials have been carried out in this research field. There are, however, many difficulties to perform in-pile SCC tests. Performing in-pile SCC tests, essential key techniques must be developed. Hence as a part of development of the key techniques for in-pile SCC tests, we have embarked on development of the test technique which enables us to obtain the information concerning the effect of such parameters as applied stress level, water chemistry, irradiation conditions, etc. on the crack initiation behavior. Although it is difficult to detect the crack initiation in in-pile SCC tests, the crack initiation can be evaluated by the detection of specimen rupture if the cross section area of the specimen is small enough. Therefore, we adopted the uniaxial constant loading (UCL) test with small tensile specimens. This paper will describe the current status of the development of several techniques for in-pile SCC initiation tests in JMTR and the results of the performance tests of the designed testing unit using the out-of-pile loop facility. (author)

  10. Pile mixing increases greenhouse gas emissions during composting of dairy manure

    Science.gov (United States)

    The effect of pile mixing on greenhouse gas (GHG) emissions from stored dairy manure was determined using large flux chambers designed to completely cover pilot-scale manure piles. GHG emissions from piles that were mixed four times during the 80 day trial were about 20% higher than unmixed piles. ...

  11. Kinematic seismic response of piles in layered soil profile

    International Nuclear Information System (INIS)

    Ahmad, I.; Khan, A.N.

    2006-01-01

    This paper is aimed at highlighting the importance of Kinematic Seismic Response of Piles, a phenomenon often ignored in dynamic analysis. A case study is presented where the end bearing pile is embedded in two layer soil system of highly contrasting stiffnesses; a typical case where kinematic loading plays important role. The pile soil system is modeled as continuous system and as discrete parameter system; both are based on BDWF (Beam on Dynamic Winkler Foundation) formulation. For discrete parameter system, a finite element software SAP2000 is used and the modeling technique of kinematic interaction in finite element software is discussed. For pile soil system modeled as continuous system, a general MATLAB code is developed capable of performing elastic site response analysis in two layer soil system, solving differential equation governing kinematic interaction, and giving as output the maximum ground displacement, maximum pile displacement, rotation, moment and shear distribution along pile length. The paper concludes that kinematic seismic actions must be evaluated particularly at the interface of soil layers of significantly differing soil stiffnesses. (author)

  12. Design phase identification of high pile rebound soils : final report

    Science.gov (United States)

    2010-12-15

    An engineering problem has occurred when installing displacement piles in certain soils. During driving, piles are rebounding excessively during each hammer blow, causing delay and as a result may not achieve the required design capacities. Piles dri...

  13. Processing Satellite Imagery To Detect Waste Tire Piles

    Science.gov (United States)

    Skiles, Joseph; Schmidt, Cynthia; Wuinlan, Becky; Huybrechts, Catherine

    2007-01-01

    A methodology for processing commercially available satellite spectral imagery has been developed to enable identification and mapping of waste tire piles in California. The California Integrated Waste Management Board initiated the project and provided funding for the method s development. The methodology includes the use of a combination of previously commercially available image-processing and georeferencing software used to develop a model that specifically distinguishes between tire piles and other objects. The methodology reduces the time that must be spent to initially survey a region for tire sites, thereby increasing inspectors and managers time available for remediation of the sites. Remediation is needed because millions of used tires are discarded every year, waste tire piles pose fire hazards, and mosquitoes often breed in water trapped in tires. It should be possible to adapt the methodology to regions outside California by modifying some of the algorithms implemented in the software to account for geographic differences in spectral characteristics associated with terrain and climate. The task of identifying tire piles in satellite imagery is uniquely challenging because of their low reflectance levels: Tires tend to be spectrally confused with shadows and deep water, both of which reflect little light to satellite-borne imaging systems. In this methodology, the challenge is met, in part, by use of software that implements the Tire Identification from Reflectance (TIRe) model. The development of the TIRe model included incorporation of lessons learned in previous research on the detection and mapping of tire piles by use of manual/ visual and/or computational analysis of aerial and satellite imagery. The TIRe model is a computational model for identifying tire piles and discriminating between tire piles and other objects. The input to the TIRe model is the georeferenced but otherwise raw satellite spectral images of a geographic region to be surveyed

  14. Pile foundation of nuclear power plant structures

    International Nuclear Information System (INIS)

    Jurkiewicz, W.J.; Thomaz, E.; Rideg, P.; Girao, M.

    1978-01-01

    The subject of pile foundation used for nuclear power plant structures, considering the experience gained by the designers of the Angra Nuclear Power Plant, Units 2 and 3 in Brazil is dealt with. The general concept of the pile foundations, including types and execution of the piles, is described briefly. Then the two basic models, i.e. the static model and the dynamic one, used in the design are shown, and the pertinent design assumptions as related to the Angra project are mentioned. The criteria which established the loading capacity of the piles are discussed and the geological conditions of the Angra site are also explained briefly, justifying the reasons why pile foundations are necessary in this project. After that, the design procedures and particularly the tools - i.e. the computer programs - are described. It is noted that the relatively simple but always time consuming job of loading determination calculations can be computerized too, as it was done on this project through the computer program SEASA. The interesting aspects of soil/structure interaction, applicable to static models, are covered in detail, showing the theoretical base wich was used in the program PILMAT. Then the advantage resulting from computerizing of the job of pile reinforcement design are mentioned, describing briefly the jobs done by the two special programs PILDES and PILTAB. The point is stressed that the effort computerizing the structural design of this project was not so much due to the required accuracy of the calculations, but mainly due to the need to save on the design time, as to allow to perform the design task within the relatively tight time schedule. A conclusion can be drawn that design of pile foundations for nuclear power plant structures is a more complex task than the design of bearing type of foundation for the same structures, but that the task can be always made easier when the design process can be computerized. (Author)

  15. Numerical Study on Dynamic Response of Pile Group Foundation of Geotechnical Centrifuge

    Directory of Open Access Journals (Sweden)

    Mao Quansheng

    2015-01-01

    Full Text Available Based on National Engineering Laboratory for Harbor Engineering Structure-Geotechnical Centrifuge Laboratory construction project, the dynamical response of piles foundation under horizontal-rocking vibration was analyzed by using finite element software Abaqus, and the displacement and stress characteristics of piles were discussed with soil between the piles reinforced by high pressure jet piles. The result indicates that in the operation of the centrifuge, foundation changes of vertical load of center pile are very small; the vertical displacement of the pile head is increasing, the vertical displacement of the pile head is no longer changed until the vibration time reaches 3 times period,; the horizontal load of piles varies with sinusoidal, the horizontal displacement amplitude is increasing, , and the vibration amplitude reaches to fixed value at 2 times vibration period.

  16. An experimental study on pile spacing effects under lateral loading in sand.

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand.

  17. 'Shrink' losses in commercially sized corn silage piles: Quantifying total losses and where they occur.

    Science.gov (United States)

    Robinson, P H; Swanepoel, N; Heguy, J M; Price, T; Meyer, D M

    2016-01-15

    Silage 'shrink' (i.e., loss of fresh chopped crop between ensiling and feedout) represents a nutrient loss which can degrade air quality as volatile carbon compounds, degrade surface waterways due to seepage, or degrade aquifers due to seepage. Virtually no research has documented shrink in large silage piles. The term 'shrink' is often ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost in the drying oven (vcoDM). Corn silage piles (4 wedge, 2 rollover/wedge, 1 bunker) from 950 to 12,204 tonnes as built, on concrete (4), soil (2) and a combination (1) in California's San Joaquin Valley, using a bacterial inoculant, covered within 24 h with an oxygen barrier inner film and black/white outer plastic, fed out using large front end loaders through an electronic feed tracking system, and from the 2013 crop year, were used. Shrink as WW, oDM and vcoDM were 90±17, 68±18 and 28±21 g/kg, suggesting that much WW shrink is water and much oDM shrink is volatiles lost during analytical oven drying. Most shrink occurred in the silage mass with losses from exposed silage faces, as well as between exposed face silage removal and the total mixed ration mixer, being low. Silage bulk density, exposed silage face management and face use rate did not have obvious impacts on any shrink measure, but age of the silage pile during silage feedout impacted shrink losses ('older' silage piles being higher), but most strongly for WW shrink. Real shrink losses (i.e., vcoDM) of large well managed corn silage piles are low, the exposed silage face is a small portion of losses, and many proposed shrink mitigations appeared ineffective, possibly because shrink was low overall and they are largely directed at the exposed silage face. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Pile group program for full material modeling and progressive failure.

    Science.gov (United States)

    2008-12-01

    Strain wedge (SW) model formulation has been used, in previous work, to evaluate the response of a single pile or a group of piles (including its : pile cap) in layered soils to lateral loading. The SW model approach provides appropriate prediction f...

  19. Physical Modelling of Large Diameter Piles in Coarse-Grained Soil

    DEFF Research Database (Denmark)

    Brødbæk, K. T.; Augustesen, Anders Hust; Møller, M.

    2011-01-01

    of increasing the effective stresses. The test setup is thoroughly described in the paper. Two non-slender aluminium pipe piles subjected to lateral loads have been tested in the laboratory. The piles are heavily instrumented with strain gauges in order to obtain p-y curves, displacement and bending moment......Monopiles are an often-used foundation concept for offshore wind turbine converters. These piles are highly subjected to lateral loads and overturning bending moments due to wind and wave forces. To ensure enough stiffness of the foundation and an acceptable pile-head deflection, monopiles...... with diameters of 4 to 6 m are typically employed. In current practice these piles are traditionally designed by means of the p-y curve method although the method is developed and verified for slender piles in sand with diameters up to approximately 2 m. One of the limitations of the p-y curves used in current...

  20. Piles, tabs and overlaps in navigation among documents

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    2010-01-01

    Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles. In an experim......Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles....... In an experiment we compared 11 participants’ navigation with these variations and found strong task effects. Overall, overlapping windows were preferred and their structured layout worked well with some tasks. Surprisingly, tabbed documents were efficient in tasks requiring simply finding a document. Piled...... on document navigation and its support by piling....

  1. Pile-Reinforcement Behavior of Cohesive Soil Slopes: Numerical Modeling and Centrifuge Testing

    Directory of Open Access Journals (Sweden)

    Liping Wang

    2013-01-01

    Full Text Available Centrifuge model tests were conducted on pile-reinforced and unreinforced cohesive soil slopes to investigate the fundamental behavior and reinforcement mechanism. A finite element analysis model was established and confirmed to be effective in capturing the primary behavior of pile-reinforced slopes by comparing its predictions with experimental results. Thus, a comprehensive understanding of the stress-deformation response was obtained by combining the numerical and physical simulations. The response of pile-reinforced slope was indicated to be significantly affected by pile spacing, pile location, restriction style of pile end, and inclination of slope. The piles have a significant effect on the behavior of reinforced slope, and the influencing area was described using a continuous surface, denoted as W-surface. The reinforcement mechanism was described using two basic concepts, compression effect and shear effect, respectively, referring to the piles increasing the compression strain and decreasing the shear strain of the slope in comparison with the unreinforced slope. The pile-soil interaction induces significant compression effect in the inner zone near the piles; this effect is transferred to the upper part of the slope, with the shear effect becoming prominent to prevent possible sliding of unreinforced slope.

  2. Design Optimization of Piles for Offshore Wind Turbine Jacket Foundations

    DEFF Research Database (Denmark)

    Sandal, Kasper; Zania, Varvara

    Numerical methods can optimize the pile design. The aim of this study is to automatically design optimal piles for offshore wind turbine jacket foundations (Figure 1). Pile mass is minimized with constraints on axial and lateral capacity. Results indicate that accurate knowledge about soil...

  3. Finite Element Investigations on the Interaction between a Pile and Swelling Clay

    DEFF Research Database (Denmark)

    Kaufmann, Kristine Lee; Nielsen, Benjaminn Nordahl; Augustesen, Anders Hust

    of Little Belt Clay. The case study involves a circular concrete pile installed in clay immediately after an excavation. The influence of the swelling soil on the soil–pile interaction and the internal pile forces are analysed by solely observing the upper pile part positioned in the swelling zone...... of the surrounding soil implies upward shear stresses at the soil–pile interface leading to tensile vertical stresses in the pile. In the current case, they exceed the tensile strength of concrete. The tensile vertical stresses peak after 35-50 years. However, the heave of the soil continues for additional 300 years....... It appears that the development of plastic interface implies the shrinkage of the pile....

  4. CONDUCTING AND ANALYZING THE RESULTS OF THE EXPERIMENTAL BOX TEST OF RETAINING WALL MODELS WITHOUT PILES AND ON THE PILE FOUNDATION

    Directory of Open Access Journals (Sweden)

    M. A. Lisnevskyi

    2015-08-01

    Full Text Available Purpose. Taking into consideration that the bearing capacity of the foundation may be insufficient, in the study it is assumed that pile foundation can be used to reduce the impact of the construction of new retaining structures on roads and railways near the existing buildings or in areas of dense urban development and ensure the stability of the foundation. To reduce the volume of excavation it is necessary to choose the economic structure of the retaining wall. To do this, one should explore stress-strain state (SSS of the retaining walls, to develop methods to improve their strength and stability, as well as to choose the most appropriate method of their analysis. Methodology. In the design of retaining walls foundation mat and piles are considered as independent elements. Since the combined effect of the retaining wall, piles and foundation mat as well as the effect of soil or rock foundation on the structure are considered not fully, so there are some limitations in the existing design techniques. To achieve the purpose the box tests of retaining walls models without piles and with piles for studying their interaction with the surrounding soil massif were conducted. Findings. Laboratory simulation of complex systems «surrounding soil – retaining wall – pile» was carried out and on the basis of the box test results were analyzed strains and its main parameters of the stress-strain state. Analysis of the results showed that the structure of a retaining wall with piles is steady and stable. Originality. So far, in Ukraine has not been carried out similar experimental box tests with models of retaining walls in such combinations. In the article has been presented unique photos and test results, as well as their analysis. Practical value. Using the methodology of experimental tests of the retaining wall models with piles and without them gives a wider opportunity to study stress-strain state of such structures.

  5. Hybrid pulse pile-up rejection system as applied to Rutherford backscattering

    International Nuclear Information System (INIS)

    Boie, R.A.; Wildnauer, K.R.

    1977-01-01

    The problems of pulse on pulse pile-up and noise limited pile-up rejectors are considered in detail for Rutherford backscattering spectra. The forms of these spectra allow the distortions from pile-up and the residual pile-up after rejection to be understood via a simple model. Extended calculations allow us to predict the effects quite accurately. A new pile-up rejection system is described. The ''linear'' rejection method is implemented with peak stretchers and advantageously combined with an event counting rejector to provide a versatile high performance system

  6. Elementary calculation of the shutdown delay of a pile; Calcul elementaire de la periode d'extinction d'une pile

    Energy Technology Data Exchange (ETDEWEB)

    Yvon, J

    1949-04-01

    This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)

  7. An Experimental Study on Pile Spacing Effects under Lateral Loading in Sand

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2013-01-01

    Grouped and single pile behavior differs owing to the impacts of the pile-to-pile interaction. Ultimate lateral resistance and lateral subgrade modulus within a pile group are known as the key parameters in the soil-pile interaction phenomenon. In this study, a series of experimental investigation was carried out on single and group pile subjected to monotonic lateral loadings. Experimental investigations were conducted on twelve model pile groups of configurations 1 × 2, 1 × 3, 2 × 2, 3 × 3, and 3 × 2 for embedded length-to-diameter ratio l/d = 32 into loose and dense sand, spacing from 3 to 6 pile diameter, in parallel and series arrangement. The tests were performed in dry sand from Johor Bahru, Malaysia. To reconstruct the sand samples, the new designed apparatus, Mobile Pluviator, was adopted. The ultimate lateral load is increased 53% in increasing of s/d from 3 to 6 owing to effects of sand relative density. An increasing of the number of piles in-group decreases the group efficiency owing to the increasing of overlapped stress zones and active wedges. A ratio of s/d more than 6d is large enough to eliminate the pile-to-pile interaction and the group effects. It may be more in the loose sand. PMID:24453900

  8. N-Springs expedited response action performance evaluation report

    International Nuclear Information System (INIS)

    Mukherjee, B.B.

    1996-07-01

    Groundwater in the 100-NR-2 Operable Unit (OU) has been contaminated with various radionuclides, metals, and ionic constituents because of waste water disposal practices and spills associated with I 00-N Reactor operations. Of primary concern are the presence of high levels of strontium-90 in the groundwater and the discharge of 90 Sr contaminated groundwater to the nearby Columbia River through historic river bank seeps known as 'N-Springs'. In accordance with the requirements of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), remediation alternatives are currently being evaluated to address the hazardous substances and constituents in the soil and groundwater at the 100-NR-1/100-NR-2 OUs. Because of concern regarding the release of 90 Sr to the river, the Washington State Department of Ecology (Ecology) and the US Environmental Protection Agency (EPA) issued an action memorandum on September 23, 1994, to the U.S. Department of Energy (DOE), Richland Operations Office (RL), to take immediate actions consisting of a combination of a groundwater pump-and-treat system and a sheet pile barrier wall at N-Springs. By letter, dated March 23, 1995, Ecology and EPA agreed that a sheet pile construction test in December 1994 showed that the installation of the jointed hinge sheet pile wall could not be achieved in the manner specified. Ecology and EPA directed RL to proceed with the installation of the Expedited Response Action (ERA) pump-and-treat system and to (1) continue assessing accurately the flux of strontium to the river, (2) further characterize geologic and hydrologic conditions, and (3) assess design and installation alternatives related to modified barriers and expected performance

  9. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.24 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products composed thereof may be...

  10. Small-Scale Cyclic Tests on Nonslender Piles Situated in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    In the period from August 2011 till October 2011 a series of small-scale tests on pile foundations has been conducted at Aalborg University. In all the tests, the piles have been exposed to cyclic loading consisting of 20-25 load cycles and all the tests have been conducted in a pressure tank....... The objective of the tests has been to investigate the effect of pile diameter, length to diameter ratio and cyclic loading on the soil response for non-slender piles in sand....

  11. Stability of multilayer earthen barriers used to isolate mill tailings: geologic and geotechnological considerations

    Energy Technology Data Exchange (ETDEWEB)

    Zellmer, J.T.

    1981-08-01

    This report briefly discusses how seismic activity, erosion, climatic change, slope stability, differential settlement, and cover design could affect the long-term integrity of multilayer earthen cover systems. In addition, the report suggests ways to design and construct covers so that adverse impacts can be avoided or minimized. The stability of multilayer earthen barriers used to isolate uranium mill tailings depends on the morphology of the disposal site, the engineering of the barrier, the condition of the tailings, and the possible impacts of earthquakes, erosion, and climatic changes. When designing a cover for or siting a tailings pile, one must take into account both geologic and geotechnological variables. To alleviate the adverse effects of possible seismic activity, tailings piles should never be located on or near active or capable faults. Existing piles near faults should be moved to safer sites or engineered to withstand possible displacement and shaking. Liquefaction generally can be prevented if the tailings and their underlying material are compacted to a relative density of 60% or greater, or if they are kept dry. If the tailings are saturated, dewatering schemes may have to be used. Erosion may be caused by streams, glaciers, or wind, depending on the geomorphic and atmospheric conditions at the site. Fluvial erosion can be prevented by using dikes (and avoided by initially siting the pile a safe distance away from stream courses). In some cases, fluvial waters or rainfall may have to be rerouted over the pile via armored ditches. Eolian erosion can be minimized by vegetating the disposal site or covering it with gravel. Because of the wide geomorphic and geotechnological variations extant at most sites, a single cover design cannot be cost-effectively and efficiently used at all sites.

  12. Stability of multilayer earthen barriers used to isolate mill tailings: geologic and geotechnological considerations

    International Nuclear Information System (INIS)

    Zellmer, J.T.

    1981-08-01

    This report briefly discusses how seismic activity, erosion, climatic change, slope stability, differential settlement, and cover design could affect the long-term integrity of multilayer earthen cover systems. In addition, the report suggests ways to design and construct covers so that adverse impacts can be avoided or minimized. The stability of multilayer earthen barriers used to isolate uranium mill tailings depends on the morphology of the disposal site, the engineering of the barrier, the condition of the tailings, and the possible impacts of earthquakes, erosion, and climatic changes. When designing a cover for or siting a tailings pile, one must take into account both geologic and geotechnological variables. To alleviate the adverse effects of possible seismic activity, tailings piles should never be located on or near active or capable faults. Existing piles near faults should be moved to safer sites or engineered to withstand possible displacement and shaking. Liquefaction generally can be prevented if the tailings and their underlying material are compacted to a relative density of 60% or greater, or if they are kept dry. If the tailings are saturated, dewatering schemes may have to be used. Erosion may be caused by streams, glaciers, or wind, depending on the geomorphic and atmospheric conditions at the site. Fluvial erosion can be prevented by using dikes (and avoided by initially siting the pile a safe distance away from stream courses). In some cases, fluvial waters or rainfall may have to be rerouted over the pile via armored ditches. Eolian erosion can be minimized by vegetating the disposal site or covering it with gravel. Because of the wide geomorphic and geotechnological variations extant at most sites, a single cover design cannot be cost-effectively and efficiently used at all sites

  13. In-pile IASCC growth tests of irradiated stainless steels in JMTR

    Energy Technology Data Exchange (ETDEWEB)

    Chimi, Yasuhiro; Kasahara, Shigeki; Ise, Hideo; Kawaguchi, Yoshihiko; Nakano, Junichi; Nishiyama, Yutaka [Japan Atomic Energy Agency, Nuclear Safety Research Center, Tokai, Ibaraki (Japan); Shibata, Akira; Ohmi, Masao [Japan Atomic Energy Agency, Oarai Research and Development Center, Oarai, Ibaraki (Japan)

    2012-03-15

    The Japan Atomic Energy Agency (JAEA) has an in-pile irradiation-assisted stress corrosion cracking (IASCC) test plan to evaluate in-situ effects of neutron/{gamma}-ray irradiation on crack growth of irradiated stainless steels under high-temperature water conditions for commercial boiling water reactors (BWRs) using the Japan Materials Testing Reactor (JMTR). Crack growth rate and its electrochemical corrosion potential (ECP) dependence are different between in-pile test and post irradiation examination (PIE), but these differences are not fully understood. The objectives of the present study are to understand the difference between in-pile and out-of-pile IASCC growth and to confirm the effectiveness of mitigation due to lowering ECP on in-pile crack growth rates. For in-pile crack growth tests, we have selected a large compact tension specimen such as 0.5T-CT because of validity of SCC growth test at a high stress intensity factor (K-value). For loading a 0.5T-CT specimen up to K - 30 MPa {radical}m, we have adopted a lever type loading unit for in-pile crack growth tests in the JMTR. In this report, an in-pile test plan for crack growth of irradiated SUS316L stainless steels under simulated BWR conditions in the JMTR and current status of development of in-pile crack growth test techniques are presented. (author)

  14. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof... CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile fabrics and products composed thereof. The fiber content of pile fabrics or products made thereof may be...

  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. After the fire: preparing the Windscale Piles for decommissioning

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The Windscale Piles in the UK were taken out of service in 1957 after a fire in Pile 1. They have remained essentially in the same state since that time and during this period there have been periodic inspections of the complete structures to ensure that there is no degradation taking place. The Piles are in a safe condition and would remain so for a considerable period (50 years or more) provided they were undisturbed. However, the Piles must be decommissioned at some time and clearly this will require preparatory work which is now being carried out. The work is scheduled for completion in 1994, at a cost of Pound 8 million at present day prices. (author)

  18. Field test on sand compaction pile method with copper slag sand; Dosuisai slag wo mochiita SCP koho no shiken seko

    Energy Technology Data Exchange (ETDEWEB)

    Minami, K.; Matsui, H.; Naruse, E.; Kitazume, M. [Port and Harbour Research Inst., Kanagawa (Japan)

    1997-09-20

    This paper describes the sand compaction pile (SCP) method using copper slag sand. The SCP method is a method by which sand compaction piles are constructed in the ground, and improvement can be obtained in a short period. This method has been widely used even in the port areas for enhancing the bearing power of soft clay ground and the lateral resistance of sheet pile. A great deal of sand is required as a material. The sand requires high permeability, proper size distribution with less fine particle fraction content, easy compaction property with enough strength, and easy discharging property from the casing of construction machines as required properties. Recently, it becomes hard to secure proper sand materials. The copper slag sand is obtained from refining process of copper as a by-product which is quenched in water flow and crushed in water. The copper slag sand has higher particle density than that of sand, excellent permeability, and similar size distribution to that of sand. From compaction drainage triaxial compression test and permeability test, it was found that the mechanical properties of copper slag sand did not change by the crushing of grains with keeping excellent permeability. Through the test construction, applicability of the copper slag sand to the SCP method could be confirmed as an alternate material of sand. 17 refs., 9 figs., 4 tabs.

  19. Experimental Investigations of Tension Piles in Sand Subjected to Static and Cyclic Loading

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    to accumulated upwards displacement of the piles and, thus, undesired deflection of the wind turbine structure. This study concerns the effect of cyclic loading on a pile installed in dense sand and loaded in tension. A new laboratory test setup was constructed to make these pile load tests. The thesis discusses...... the advantages and disadvantages of the test setup. The results of cyclic loading tests showed that the loading conditions are very important for the behavior of piles. Some wind and wave conditions can be beneficial and increase the pile capacity while other conditions can be damaging and reduce the pile......The present thesis regards the behavior of the piles in jacket pile foundations used for offshore wind turbines. The piles are often loaded in tension because of the combination of wind and wave conditions and the low self-weight of the wind turbine. The repeated cyclic loading can lead...

  20. SHAKING TABLE TESTS ON SEISMIC DEFORMATION OF PILE SUPPORTED PIER

    Science.gov (United States)

    Fujita, Daiki; Kohama, Eiji; Takenobu, Masahiro; Yoshida, Makoto; Kiku, Hiroyoshi

    The seismic deformation characeteristics of a pile supported pier was examined with the shake table test, especially focusing on the pier after its deformation during earthquakes. The model based on the similitude of the fully-plastic moment in piles was prepared to confirm the deformation and stress characteristic after reaching the fully-plastic moment. Moreover, assuming transportation of emergency supplies and occurrence of after shock in the post-disaster period, the pile supported pier was loaded with weight after reaching fully-plastic moment and excited with the shaking table. As the result, it is identified that the displacement of the pile supported pier is comparatively small if bending strength of piles does not decrease after reaching fully-plastic moment due to nonoccourrence of local backling or strain hardening.

  1. Experimental study on performance of laterally loaded plumb and battered piles in layered sand

    Directory of Open Access Journals (Sweden)

    Bushra S. Albusoda

    2017-09-01

    Full Text Available This study introduces a series of single and pile group model tests subjected to lateral loads in . multilayered sand from Karbala, Iraq. The aim of this study is to investigate: the performance of the pile groups subjected to lateral loads; in which the pile batter inclination angle is changed; the effect of pile spacing (s/d ratio, the influence of using different number of piles and pile group configuration. Results revealed that the performance of single negative (Reverse Battered piles with inclination of 10° and 20° show a gain of 32% and 76 % in the ultimate lateral capacity over the regular ones. For pile groups, the use of a combination of regular, negative and positive battered piles in different angles of inclination within the same group shows a significant increase in the ultimate lateral load carrying capacity. Increasing the spacing between piles in groups of the same category shows an increase in the group efficiency, also changing the piles number within the group by using different patterns will influence the ultimate lateral resistance of the pile group.

  2. Pulse pile-up. I: Short pulses

    International Nuclear Information System (INIS)

    Wilkinson, D.H.

    1990-07-01

    The search for rare large pulses against an intense background of smaller ones involves consideration of pulse pile-up. Approximate methods are presented, based on ruin theory, by which the probability of such pile-up may be estimated for pulses of arbitrary form and of arbitrary pulse-height distribution. These methods are checked against cases for which exact solutions are available. The present paper is concerned chiefly with short pulses of finite total duration. (Author) (5 refs., 24 figs.)

  3. Centrifuge modeling of rapid load tests with open-ended piles

    NARCIS (Netherlands)

    Nguyen, T.C.; Van Lottum, H.; Holscher, P.; Van Tol, A.F.

    2012-01-01

    Rapid and static load tests were conducted on open-ended and close-ended piles in the Deltares GeoCentriflige. hi flight, a pile was driven into the soil. Both fme-grained sand and silt beds were tested. Both the rapid and static soil resistances o f a close-ended pile were higher than the soil

  4. Analysis of Wave Fields induced by Offshore Pile Driving

    Science.gov (United States)

    Ruhnau, M.; Heitmann, K.; Lippert, T.; Lippert, S.; von Estorff, O.

    2015-12-01

    Impact pile driving is the common technique to install foundations for offshore wind turbines. With each hammer strike the steel pile - often exceeding 6 m in diameter and 80 m in length - radiates energy into the surrounding water and soil, until reaching its targeted penetration depth. Several European authorities introduced limitations regarding hydroacoustic emissions during the construction process to protect marine wildlife. Satisfying these regulations made the development and application of sound mitigation systems (e.g. bubble curtains or insulation screens) inevitable, which are commonly installed within the water column surrounding the pile or even the complete construction site. Last years' advances have led to a point, where the seismic energy tunneling the sound mitigation systems through the soil and radiating back towards the water column gains importance, as it confines the maximum achievable sound mitigation. From an engineering point of view, the challenge of deciding on an effective noise mitigation layout arises, which especially requires a good understanding of the soil-dependent wave field. From a geophysical point of view, the pile acts like a very unique line source, generating a characteristic wave field dominated by inclined wave fronts, diving as well as head waves. Monitoring the seismic arrivals while the pile penetration steadily increases enables to perform quasi-vertical seismic profiling. This work is based on datasets that have been collected within the frame of three comprehensive offshore measurement campaigns during pile driving and demonstrates the potential of seismic arrivals induced by pile driving for further soil characterization.

  5. Prediction of pile set-up for Ohio soils : executive summary report.

    Science.gov (United States)

    2011-02-01

    ODOT typically uses small diameter driven pipe piles for bridge foundations. When a pile is driven into the subsurface, it disturbs and displaces the soil. As the soil surrounding the pile recovers from the installation disturbance, a time dependant ...

  6. An Estimating Formula of Lateral Load Acting on Stabilizing Piles for Landslide

    OpenAIRE

    尾崎, 叡司; 石田, 陽博

    1984-01-01

    An estimating method of lateral load acting on stabilizing piles in a raw due to the plastic deformation of soil for landslide was discussed in this paper. Special emphasis was put on the problems of the space between stabilizing piles and of lateral load induced in piles through the surrounding soils due to plastic deformation in the vicinity of piles. In order to obtain an analytical result of the lateral load acting on stabilizing piles, the authors tried to solve the equilibrium equation ...

  7. Probabilistic evaluation method for axial capacity of single pile based on pile test information. Saika shiken kekka wo koryoshita kuienchoku shijiryoku no kakuritsuronteki hyokaho

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, K.; Suzuki, M. (Shimizu Construction Co. Ltd., Tokyo (Japan)); Nakatani, S. (Ministry of Construction Tokyo (Japan)); Matsui, K. (CTI Engineering Co. Ltd., Tokyo (Japan))

    1991-12-20

    To consider the safety and economics in the design of pile, the reasonable evaluation on estimated accuracy from the accuracy of equation of pile capacity and probabilistic evaluation method is necessary. Therefore, the data analysis based on the collection and summary of the results from load tests of piles is one of powerful approach. In this study, selection of the parameters that cannot obtained from probabilistic model and load test and combination between statistical and experimental data by using Baysian probabilistic theory was examined. As the feature of this study, use of the design pile capacity equation based on the model of evaluation of pile capacity, consideration of the intrinsic difference between statistical data and results of load tests by using Baysian probabilistic theory and quantitative examination of applicability of the proposed method and the results of load tests are given. 24 refs., 5 figs., 7 tabs.

  8. The effect of loading rate on pile bearing capacity of saturated sand

    NARCIS (Netherlands)

    Archeewa, E.

    2005-01-01

    Pile load tests are commonly used by engineers to determine its bearing capacity. At present, there are three methods of pile load tests: the static, the dynamic and the quasi-static test. The static pile load test is done by applying an axial load on the pile with a long duration. The dynamic and

  9. Critical sizes and flux distributions in the shut down pile

    International Nuclear Information System (INIS)

    Banchereau, A.; Berthier, P.; Genthon, J.P.; Gourdon, C.; Lattes, R.; Martelly, J.; Mazancourt, R. de; Portes, L.; Sagot, M.; Schmitt, A.P.; Tanguy, P.; Teste du Bailler, A.; Veyssiere, A.

    1957-01-01

    An important part of the experiments carried out on the reactor G1 during a period of shut-down has consisted in determinations of critical sizes, and measurements of flux distribution by irradiations of detectors. This report deals with the following points: 1- Critical sizes of the flat pile, the long pile and the uranium-thorium pile. 2- Flux charts of the same piles, and study of an exponential experiment. 3- Determination of the slit effect. 4- Calculation of the anisotropy of the lattice. 5- Description of the experimental apparatus of the irradiation measurements. (author) [fr

  10. Reducing Local Scouring at Bridge Piles Using Collars and Geobags

    Directory of Open Access Journals (Sweden)

    Shatirah Akib

    2014-01-01

    Full Text Available The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most significant scour reduction for the front and rear piles, respectively. Moreover, the independent steel collar showed better efficiency than the independent geobag below the sediment level around the bridge piles.

  11. Assessment of Time Functions for Piles Driven in Clay

    DEFF Research Database (Denmark)

    Augustesen, Anders; Andersen, Lars; Sørensen, Carsten Steen

    The vertical bearing capacity of piles situated in clay is studied with regard to the long-term set-up. A statistical analysis is carried out on the basis of data from numerous static loading tests. The database covers a wide range of both soil and pile properties, which ensures a general....... Hence, it is suggested that a constant set-up factor should be applied for the prediction of pile capacities at a given time after initial driving....

  12. Lateral displacement and pile instability due to soil liquefaction using numerical model

    Directory of Open Access Journals (Sweden)

    Abdel-Salam Ahmed Mokhtar

    2014-12-01

    Extensive studies were performed to investigate the effects of soil submergence, pile diameter, earthquake magnitude and duration on pile lateral deformation and developed bending moment along pile shaft. Study results show that earthquake magnitude and time duration have a particular effect on the pore water pressure generation and hence pile lateral deformation and bending moments. They also show the benefits of using relatively large piles to control the lateral displacement. Recommendations are presented for designers to perform comprehensive analysis and avoid buckling and plastic hinge failures.

  13. Seismic Dynamic Damage Characteristics of Vertical and Batter Pile-supported Wharf Structure Systems

    Directory of Open Access Journals (Sweden)

    Li Jiren

    2015-10-01

    Full Text Available Considering a typical steel pipe pile-supported wharf as the research object, finite element analytical models of batter and vertical pile structures were established under the same construction site, service, and geological conditions to investigate the seismic dynamic damage characteristics of vertical and batter pile-supported wharf structures. By the numerical simulation and the nonlinear time history response analysis of structure system and the moment–axial force relation curve, we analyzed the dynamic damage characteristics of the two different structures of batter and vertical piles under different seismic ground motions to provide reasonable basis and reference for designing and selecting a pile-supported wharf structure. Results showed that the axial force of batter piles was dominant in the batter pile structure and that batter piles could effectively bear and share seismic load. Under the seismic ground motion with peak ground acceleration (PGA of 350 Gal and in consideration of the factors of the design requirement of horizontal displacement, the seismic performance of the batter pile structure was better than that of the vertical pile structure. Under the seismic ground motion with a PGA of 1000 Gal, plastic failure occurred in two different structures. The contrastive analysis of the development of plastic damage and the absorption and dissipation for seismic energy indicated that the seismic performance of the vertical pile structure was better than that of the batter pile structure.

  14. Synthesis of concrete bridge piles prestressed with CFRP systems.

    Science.gov (United States)

    2017-06-01

    The Texas Department of Transportation frequently constructs prestressed concrete piles for use in bridge : foundations. Such prestressed concrete piles are typically built with steel strands that are highly susceptible to : environmental degradation...

  15. Out-of-pile and in-pile temperature noise investigations: a survey of methods results and models

    International Nuclear Information System (INIS)

    Dentico, G.; Giovannini, R.; Marseguerra, M.; Pacilio, N.; Taglienti, S.; Tosi, V.; Vigo, A.; Oguma, R.

    1982-01-01

    A review is given of the main results obtained from temperature noise measurements performed in out-of-pile sodium loops on fast fuel element mock-ups. Sources of data were thermocouples placed in the central axis of the channel downstream from the bundle end. Autoregressive moving average (ARMA) models have been applied to several temperature time series; the analysis shows that a simple ARMA (3, 2) model adequately accounts for the observed fluctuations. Finally, highlights of a heat transfer stochastic model are also reported together with a preliminary validation against in-pile experimental data. (author)

  16. The reactor Cabri; La pile cabri

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J; Millot, J P [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1964-07-01

    circumstances... - experimental investigations on power excursions linked with precise initial conditions: the aim of this work is to define the basis for theoretical research, and the limits beyond which the risks of explosion cease to be negligible. The research work will be done so as to enable checking with outside reactor experiments and to continue them in the explosion field. - studies of the behaviour of the reactor control-instrumentation. - experimental investigations related with transient operation with initial short life (study of boiling, temperature measurements, vacuum pressure and fraction...) with the aim of defining the hypotheses of a theory on swimming-pool reactor kinetics related to heat transfer phenomena, - investigations of the behaviour of fuels in reactors (these experiments are planned to be carried out in loops) Preliminary experimental results. CABRI went critical on the 21 December 1963. The first transient experiments are expected for March 1964. (authors) [French] II devenait necessaire de construire en France une pile qui permette d'etudier les conditions de fonctionnement des installations futures, de choisir, tester et mettre au point les dispositifs de securite a adopter. On a choisi une pile a eau, type de pile qui correspond aux constructions les plus nouvelles du CEA en matiere de piles laboratoire ou d'universite; il importe en effet de pouvoir evaluer les risques presentes et d'etudier les possibilites d'augmentation de puissance constamment demandees par les utilisateurs: il est particulierement interessant d'eclaircir les phenomenes d'oscillation de puissance et les risques de calefaction (burn out). Les programmes de travaux sur CABRI seront harmonises avec les travaux effectues sur les Spert americains de meme type; lors de sa construction des contacts fructueux ont ete etablis avec les specialistes americains qui ont defini les premiers de ces reacteurs. La communication donne une description sommaire de la pile et decrit le

  17. Lateral response of pile foundations in liquefiable soils

    Directory of Open Access Journals (Sweden)

    Asskar Janalizadeh

    2015-10-01

    Full Text Available Liquefaction has been a main cause of damage to civil engineering structures in seismically active areas. The effects of damage of liquefaction on deep foundations are very destructive. Seismic behavior of pile foundations is widely discussed by many researchers for safer and more economic design purposes. This paper presents a pseudo-static method for analysis of piles in liquefiable soil under seismic loads. A free-field site response analysis using three-dimensional (3D numerical modeling was performed to determine kinematic loads from lateral ground displacements and inertial loads from vibration of the superstructure. The effects of various parameters, such as soil layering, kinematic and inertial forces, boundary condition of pile head and ground slope, on pile response were studied. By comparing the numerical results with the centrifuge test results, it can be concluded that the use of the p-y curves with various degradation factors in liquefiable sand gives reasonable results.

  18. Discovery: Pile Patterns

    Science.gov (United States)

    de Mestre, Neville

    2017-01-01

    Earlier "Discovery" articles (de Mestre, 1999, 2003, 2006, 2010, 2011) considered patterns from many mathematical situations. This article presents a group of patterns used in 19th century mathematical textbooks. In the days of earlier warfare, cannon balls were stacked in various arrangements depending on the shape of the pile base…

  19. The homogenisation of bulk material in blending piles.

    NARCIS (Netherlands)

    Gerstel, A.W.

    1979-01-01

    In this thesis the homogenisation of bulk material in three types of piles is dealt with. The homogenisation implies that the fluctuations of a material proprety in the input flow of the pile are transformed into output fluctuations, whereby the latter ones are evened out. Analyses are presented

  20. Monitoring moisture content, temperature, and humidity in whole-tree pine chip piles

    Science.gov (United States)

    John Klepac; Dana Mitchell; Jason Thompson

    2015-01-01

    Two whole-tree chip piles were monitored for moisture content, temperature, and relative humidity from October 8th, 2010 to March 16th, 2011 at a location in south Alabama. Initial moisture content samples were collected immediately after chips were delivered to the study location on October 8th for Pile 1 and October 22nd for Pile 2. During pile construction, Lascar...

  1. In-pile Hydrothermal Corrosion Evaluation of Coated SiC Ceramics and Composites

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, David [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Ang, Caen [Univ. of Tennessee, Knoxville, TN (United States); Katoh, Yutai [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Linton, Kory D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Terrani, Kurt A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-01

    Hydrothermal corrosion accelerated by water radiolysis during normal operation is among the most critical technical feasibility issues remaining for silicon carbide (SiC) composite-based cladding that could provide enhanced accident-tolerance fuel technology for light water reactors. An integrated in-pile test was developed and performed to determine the synergistic effects of neutron irradiation, radiolysis, and pressurized water flow, all of which are relevant to a typical pressurized water reactor (PWR). The test specimens were chosen to cover a range of SiC materials and a variety of potential options for environmental barrier coatings. This document provides a summary of the irradiation vehicle design, operations of the experiment, and the specimen loading into the irradiation vehicle.

  2. Picking up Clues from the Discard Pile

    Science.gov (United States)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil. On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through red, green and blue filters that have been combined into this approximately true-color image. This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench. Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches. For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench. The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed

  3. The Analysis of Soil Resistance During Screw Displacement Pile Installation

    Science.gov (United States)

    Krasinski, Adam

    2015-02-01

    The application of screw displacement piles (SDP) is still increasing due to their high efficiency and many advantages. However, one technological problem is a serious disadvantage of those piles. It relates to the generation of very high soil resistance during screw auger penetration, especially when piles are installed in non-cohesive soils. In many situations this problem causes difficulties in creating piles of designed length and diameter. It is necessary to find a proper method for prediction of soil resistance during screw pile installation. The analysis of screw resistances based on model and field tests is presented in the paper. The investigations were carried out as part of research project, financed by the Polish Ministry of Science and Higher Education. As a result of tests and analyses the empirical method for prediction of rotation resistance (torque) during screw auger penetration in non-cohesive subsoil based on CPT is proposed.

  4. Physical Modelling of Cyclic Laterally Loaded Pile in Cohesionless Soil

    DEFF Research Database (Denmark)

    Hansen, Mette; Wolf, Torben K.; Rasmussen, Kristian L.

    Offshore wind turbines are normally founded with large diameter monopiles and placed in rough environments subjected to variable lateral loads from wind and waves. A long-term lateral loading may create rotation (tilt) of the pile by change in the pile-soil system which is critical in the service......Offshore wind turbines are normally founded with large diameter monopiles and placed in rough environments subjected to variable lateral loads from wind and waves. A long-term lateral loading may create rotation (tilt) of the pile by change in the pile-soil system which is critical...... in the serviceability limit state. In this paper small-scale testing of a pile subjected to cyclic, lateral loading is treated in order to investigate the effect of cyclic loading. The test setup, which is an improvement of a previous setup, is described and the first results of testing are compared with previous...

  5. Laboratory Testing of Cyclic Laterally Loaded Pile in Cohesionless Soil

    DEFF Research Database (Denmark)

    Roesen, Hanne Ravn; Ibsen, Lars Bo; Hansen, Mette

    2013-01-01

    Offshore wind turbines are normally founded with large diameter monopiles and placed in rough environments subjected to variable lateral loads from wind and waves. A long-term lateral loading may create rotation (tilt) of the pile by change in the pile-soil system which is critical in the service......Offshore wind turbines are normally founded with large diameter monopiles and placed in rough environments subjected to variable lateral loads from wind and waves. A long-term lateral loading may create rotation (tilt) of the pile by change in the pile-soil system which is critical...... in the serviceability limit state. In this paper small-scale testing of a pile subjected to cyclic, lateral loading is treated in order to investigate the effect of cyclic loading. The test setup, which is an improvement of a previous setup, is described and the first results of testing are compared with previous...

  6. Modelling of pile load tests in granular soils : Loading rate effects

    NARCIS (Netherlands)

    Nguyen, T.C.

    2017-01-01

    People have used pile foundations throughout history to support structures by transferring
    loads to deeper and stronger soil layers. One of the most important questions during the design of the pile foundation is the bearing capacity of the pile. The most reliable method for determining the

  7. Field testing of stiffened deep cement mixing piles under lateral cyclic loading

    Science.gov (United States)

    Raongjant, Werasak; Jing, Meng

    2013-06-01

    Construction of seaside and underground wall bracing often uses stiffened deep cement mixed columns (SDCM). This research investigates methods used to improve the level of bearing capacity of these SDCM when subjected to cyclic lateral loading via various types of stiffer cores. Eight piles, two deep cement mixed piles and six stiffened deep cement mixing piles with three different types of cores, H shape cross section prestressed concrete, steel pipe, and H-beam steel, were embedded though soft clay into medium-hard clay on site in Thailand. Cyclic horizontal loading was gradually applied until pile failure and the hysteresis loops of lateral load vs. lateral deformation were recorded. The lateral carrying capacities of the SDCM piles with an H-beam steel core increased by 3-4 times that of the DCM piles. This field research clearly shows that using H-beam steel as a stiffer core for SDCM piles is the best method to improve its lateral carrying capacity, ductility and energy dissipation capacity.

  8. Geometric stability, electronic structure, and intercalation mechanism of Co adatom anchors on graphene sheets

    International Nuclear Information System (INIS)

    Tang, Yanan; Chen, Weiguang; Li, Chenggang; Dai, Xianqi; Li, Wei

    2015-01-01

    We perform a systematic study of the adsorption of Co adatom on monolayer and bilayer graphene sheets, and the calculated results are compared through the van der Waals density functional (vdW-DF) and the generalized gradient approximation of Perdew, Burke and Ernzernhof (GGA + PBE) methods. For the single Co adatom, its adsorption energy at vacancy site was found to be larger than at the high-symmetry adsorption sites. For the different vdW corrections, the calculated adsorption energies of Co adatom on graphene substrates are slightly changed to some extent, but they do not affect the most preferable adsorption configurations. NEB calculations prove that the Co adatom has smaller energy barrier within pristine bilayer graphene (PBG) than that on the upper layer, indicating the high mobility of Co atom anchors at overlayer and easily aggregates. For the PBG substrate, the Co adatom intercalates into graphene sheets with a large energy barrier (9.29 eV). On the bilayer graphene with a single-vacancy (SV), the Co adatom can easily be trapped at the SV site and intercalates into graphene sheets with a much lower energy barrier (2.88 eV). These results provide valuable information on the intercalation reaction and the formation mechanism of metal impurity in graphene sheets. (paper)

  9. 30 CFR 56.16002 - Bins, hoppers, silos, tanks, and surge piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bins, hoppers, silos, tanks, and surge piles... MINES Materials Storage and Handling § 56.16002 Bins, hoppers, silos, tanks, and surge piles. (a) Bins, hoppers, silos, tanks, and surge piles, where loose unconsolidated materials are stored, handled or...

  10. 30 CFR 57.16002 - Bins, hoppers, silos, tanks, and surge piles.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bins, hoppers, silos, tanks, and surge piles... NONMETAL MINES Materials Storage and Handling § 57.16002 Bins, hoppers, silos, tanks, and surge piles. (a) Bins, hoppers, silos, tanks, and surge piles, where loose unconsolidated materials are stored, handled...

  11. Application of self-balanced loading test to socketed pile in weak rock

    Science.gov (United States)

    Cheng, Ye; Gong, Weiming; Dai, Guoliang; Wu, JingKun

    2008-11-01

    Method of self-balanced loading test differs from the traditional methods of pile test. The key equipment of the test is a cell. The cell specially designed is used to exert load which is placed in pile body. During the test, displacement values of the top plate and the bottom plate of the cell are recorded according to every level of load. So Q-S curves can be obtained. In terms of test results, the bearing capacity of pile can be judged. Equipments of the test are simply and cost of it is low. Under some special conditions, the method will take a great advantage. In Guangxi Province, tertiary mudstone distributes widely which is typical weak rock. It is usually chosen as the bearing stratum of pile foundation. In order to make full use of its high bearing capacity, pile is generally designed as belled pile. Foundations of two high-rise buildings which are close to each other are made up of belled socketed piles in weak rock. To obtain the bearing capacity of the belled socketed pile in weak rock, loading test in situ should be taken since it is not reasonable that experimental compression strength of the mudstone is used for design. The self-balanced loading test was applied to eight piles of two buildings. To get the best test effect, the assembly of cell should be taken different modes in terms of the depth that pile socketed in rock and the dimension of the enlarged toe. The assembly of cells had been taken three modes, and tests were carried on successfully. By the self-balanced loading test, the large bearing capacities of belled socketed piles were obtained. Several key parameters required in design were achieved from the tests. For the data of tests had been analyzed, the bearing performance of pile tip, pile side and whole pile was revealed. It is further realized that the bearing capacity of belled socketed pile in the mudstone will decrease after the mudstone it socketed in has been immerged. Among kinds of mineral ingredient in the mudstone

  12. 3D Centrifuge Modeling of the Effect of Twin Tunneling to an Existing Pile Group

    Directory of Open Access Journals (Sweden)

    M. A. Soomr

    2017-10-01

    Full Text Available In densely built urban areas, it is inevitable that tunnels will be constructed near existing pile groups. The bearing capacity of a pile group depends on shear stress along the soil-pile interface and normal stress underneath the pile toe while the two would be adversely affected by the unloading process of tunneling. Although extensive studies have been conducted to investigate the effects of tunnel construction on existing single piles, the influence of twin tunnel advancement on an existing pile group is merely reported in the literature. In this study, a series of three-dimensional centrifuge tests were carried out to investigate the response of an existing pile group under working load subjected to twin tunneling at various locations in dry Toyoura sand. In each twin tunneling test, the first tunnel is constructed near the mid-depth of the pile shaft, while the second tunnel is subsequently constructed either next to, below or right underneath the pile toe (Tests G_ST, G_SB and G_SU, respectively. Among the three tests, the 2nd tunnel excavated near the pile toe (Test G_ST results in the smallest settlement but the largest transverse tilting (0.2% of pile group. Significant bending moment was induced at the pile head (1.4 times of its bending moment capacity due to the 2nd tunnel T. On the contrary, tunneling right underneath the toe of pile (i.e., Test G_SU results in the smallest tilting but largest settlement of the pile group (4.6% of pile diameter and incremental mobilisation of shaft resistance (13%. Due to stress release by the twin tunneling, the axial force taken by the front piles close to tunnels was reduced and partially transferred to the rear piles. This load transfer can increase the axial force in rear piles by 24%.

  13. Cellulose insulation as an air barrier

    Energy Technology Data Exchange (ETDEWEB)

    Manning, K.

    1989-10-01

    The objective of this study was to determine if a wet sprayed cellulose wall insulation system would function satisfactorily without use of a polyethylene air/vapour barrier. The research was designed to demonstrate that this particular insulation system would form enough of a barrier to air leakage, that moisture accumulation from condensation and vapour diffusion would be insignificant. Field work conducted in Alberta, involved construction of a conventional duplex housing unit which was insulated with wet sprayed cellulose in the exterior walls and dry loose-fill cellulose in the attic areas. One half of the unit did not have a polyethylene air/vapor barrier installed. Air leakage and exterior wall moisture levels were monitored for a year following construction. Data collected during this time indicated that the moisture added to the walls during the insulating process was dissipated over the study period. The presence of polyethylene sheeting had no significant effect on the moisture levels in either the wall or attic areas of the test structure. On the other hand, testing indicated that the use of polyethylene sheeting in the wall system did serve to improve blower door air test results. In conclusion, although the air leakage resistance apparently provided by the polyethylene sheeting is significant, the amount is probably not more than could otherwise be obtained by more careful attention to sealing procedures such as those used in the airtight drywall technique. A more important finding is that the use of polyethylene sheeting is not essential in a structure which has the degree of air leakage resistance provided by the insulation system used in this project. 6 figs., 2 tabs.

  14. Static Tension Tests on Axially Loaded Pile Segments in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    This paper provides laboratory test results of static axially loaded piles in sand. With a newly developed test setup, the pile-soil interface friction was investigated by using an open-ended steel pile segment with a diameter of 0.5 m. Use of a pile length of 1 m enabled the pile-soil interface...... friction to be analyzed at a given soil horizon while increasing the vertical effective stress in the sand. Test results obtained by this approach can be analyzed as single t-z curves and compared to predictions of unit shaft friction from current design methods for offshore foundations. The test results...... showed best agreement with the traditional design method given in the American Petroleum Institute (API) design code. When t-z curves obtained from the test results were compared to t-z curve formulations found in the literature, the Zhang formulation gave good predictions of the initial and post...

  15. The Analysis of Soil Resistance During Screw Displacement Pile Installation

    Directory of Open Access Journals (Sweden)

    Krasinski Adam

    2015-02-01

    Full Text Available The application of screw displacement piles (SDP is still increasing due to their high efficiency and many advantages. However, one technological problem is a serious disadvantage of those piles. It relates to the generation of very high soil resistance during screw auger penetration, especially when piles are installed in non-cohesive soils. In many situations this problem causes difficulties in creating piles of designed length and diameter. It is necessary to find a proper method for prediction of soil resistance during screw pile installation. The analysis of screw resistances based on model and field tests is presented in the paper. The investigations were carried out as part of research project, financed by the Polish Ministry of Science and Higher Education. As a result of tests and analyses the empirical method for prediction of rotation resistance (torque during screw auger penetration in non-cohesive subsoil based on CPT is proposed.

  16. Numerical and experimental assessment of thermal performance of vertical energy piles: An application

    International Nuclear Information System (INIS)

    Gao Jun; Zhang Xu; Liu Jun; Li Kuishan; Yang Jie

    2008-01-01

    A district space heating and cooling system using geothermal energy from bearing piles was designed in Shanghai and will be installed in two years before 2010. This paper describes the pile-foundation heat exchangers applied in an energy pile system for an actual architectural complex in Shanghai, 30% of whose cooling/heating load was designed to be provided by a ground-source heat pump (GSHP) system using the energy piles. In situ performance tests of heat transfer are carried out to figure out the most efficient type of energy pile and to specify the design of energy pile system. Numerical investigation is also performed to confirm the test results and to demonstrate the medium temperature variations along the pipes. The averaged heat resistance and heat injection rate of different types of energy piles are calculated from the test and numerical results. The effect of pile type, medium flow rate and inlet temperature on thermal performance is separately discussed. From the viewpoint of energy efficiency and adjustability, the W-shaped underground heat exchanger with moderate medium flow rate is finally adopted for the energy pile system

  17. Pile Structure Program, Projected Start Date : January 1, 2010 (Implementation).

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Chris; Corbett, Catherine [Lower Columbia River Estuary Partnership; Ebberts, Blaine [U.S. Army Corps of Engineers

    2009-07-27

    The 2008 Federal Columbia River Power System Biological Opinion includes Reasonable and Prudent Alternative 38-Piling and Piling Dike Removal Program. This RPA directs the Action Agencies to work with the Estuary Partnership to develop and implement a piling and pile dike removal program. The program has since evolved to include modifying pile structures to enhance their habitat value and complexity by adding large woody debris. The geographic extent of the Pile Structure Program (PSP) includes all tidally-influenced portions of the lower Columbia River below Bonneville Dam; however, it will focus on the mainstem. The overarching goal of the PSP is to enhance and restore ecosystem structure and function for the recovery of federally listed salmonids through the active management of pile structures. To attain this goal, the program team developed the following objectives: (1) Develop a plan to remove or modify pile structures that have lower value to navigation channel maintenance, and in which removal or modification will present low-risk to adjacent land use, is cost-effective, and would result in increased ecosystem function. (2) Determine program benefits for juvenile salmonids and the ecosystem through a series of intensively monitored pilot projects. (3) Incorporate best available science and pilot project results into an adaptive management framework that will guide future management by prioritizing projects with the highest benefits. The PSP's hypotheses, which form the basis of the pilot project experiments, are organized into five categories: Sediment and Habitat-forming Processes, Habitat Conditions and Food Web, Piscivorous Fish, Piscivorous Birds, and Toxic Contaminant Reduction. These hypotheses are based on the effects listed in the Estuary Module (NOAA Fisheries in press) and others that emerged during literature reviews, discussions with scientists, and field visits. Using pilot project findings, future implementation will be adaptively managed

  18. Dynamic Soil-Pile Interaction for large diameter monopile foundations

    DEFF Research Database (Denmark)

    Zania, Varvara

    2013-01-01

    of the study is to analyse the dynamic interaction of the soil and a single pile embedded in it by accounting for the geometric and stiffness properties of the pile. In doing so, a semi – analytical approach is adopted based on the fundamental solution of horizontal pile vibration by Novak and Nogami (1977...... eigenfrequencies of the soil layer do not affect the soil – pile interaction. The decrease of the eigefrequency of the OWT depends on the aforementioned variation of the dynamic stiffness and the slenderness ratio of the monopile.......Monopile foundations have been used in a large extent to support offshore wind turbines (OWT), being considered as a reliable and cost effective design solution. The accurate estimation of their dynamic response characteristics is essential, since the design of support structures for OWTs has been...

  19. Static Load Test on Instrumented Pile - Field Data and Numerical Simulations

    Science.gov (United States)

    Krasiński, Adam; Wiszniewski, Mateusz

    2017-09-01

    Static load tests on foundation piles are generally carried out in order to determine load - the displacement characteristic of the pile head. For standard (basic) engineering practices this type of test usually provides enough information. However, the knowledge of force distribution along the pile core and its division into the friction along the shaft and the resistance under the base can be very useful. Such information can be obtained by strain gage pile instrumentation [1]. Significant investigations have been completed on this technology, proving its utility and correctness [8], [10], [12]. The results of static tests on instrumented piles are not easy to interpret. There are many factors and processes affecting the final outcome. In order to understand better the whole testing process and soil-structure behavior some investigations and numerical analyses were done. In the paper, real data from a field load test on instrumented piles is discussed and compared with numerical simulation of such a test in similar conditions. Differences and difficulties in the results interpretation with their possible reasons are discussed. Moreover, the authors used their own analytical solution for more reliable determination of force distribution along the pile. The work was presented at the XVII French-Polish Colloquium of Soil and Rock Mechanics, Łódź, 28-30 November 2016.

  20. ‘Shrink’ losses in commercially sized corn silage piles: Quantifying total losses and where they occur

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, P.H.; Swanepoel, N.; Heguy, J.M.; Price, T.; Meyer, D.M., E-mail: phrobinson@ucdavis.edu [Department of Animal Science, UCCE Stanislaus, San Joaquin & Merced Counties, University of California, Davis, CA 95616 (United States)

    2016-01-15

    Silage ‘shrink’ (i.e., loss of fresh chopped crop between ensiling and feedout) represents a nutrient loss which can degrade air quality as volatile carbon compounds, degrade surface waterways due to seepage, or degrade aquifers due to seepage. Virtually no research has documented shrink in large silage piles. The term ‘shrink’ is often ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost in the drying oven (vcoDM). Corn silage piles (4 wedge, 2 rollover/wedge, 1 bunker) from 950 to 12,204 tonnes as built, on concrete (4), soil (2) and a combination (1) in California's San Joaquin Valley, using a bacterial inoculant, covered within 24 h with an oxygen barrier inner film and black/white outer plastic, fed out using large front end loaders through an electronic feed tracking system, and from the 2013 crop year, were used. Shrink as WW, oDM and vcoDM were 90 ± 17, 68 ± 18 and 28 ± 21 g/kg, suggesting that much WW shrink is water and much oDM shrink is volatiles lost during analytical oven drying. Most shrink occurred in the silage mass with losses from exposed silage faces, as well as between exposed face silage removal and the total mixed ration mixer, being low. Silage bulk density, exposed silage face management and face use rate did not have obvious impacts on any shrink measure, but age of the silage pile during silage feedout impacted shrink losses (‘older’ silage piles being higher), but most strongly for WW shrink. Real shrink losses (i.e., vcoDM) of large well managed corn silage piles are low, the exposed silage face is a small portion of losses, and many proposed shrink mitigations appeared ineffective, possibly because shrink was low overall and they are largely directed at the exposed silage face. - Highlights: • Corn silage piles were used to measure ‘shrink’ from construction to feedout • Shrink was wet weight, dry weight (oDM) and oDM volatiles corrected

  1. Estimating setup of driven piles into Louisiana clayey soils.

    Science.gov (United States)

    2010-11-15

    Two types of mathematical models for pile setup prediction, the Skov-Denver model and the newly developed rate-based model, have been established from all the dynamic and static testing data, including restrikes of the production piles, restrikes, st...

  2. Load-bearing Characters Analysis of Large Diameter Rock-Socketed Filling Piles Based on Self-Balanced Method

    Science.gov (United States)

    tongqing, Wu; liang, Li; xinjian, Liu; Xu, nianchun; Tian, Mao

    2018-03-01

    Self-balanced method is carried out on the large diameter rock-socketed filling piles of high-pile wharf at Inland River, to explore the distribution laws of load-displacement curve, pile internal force, pile tip friction resistance and pile side friction resistance under load force. The results showed that: the tip resistance of S1 and S2 test piles accounted for 53.4% and 53.6% of the pile bearing capacity, respectively, while the total side friction resistance accounted for 46.6% and 46.4% of the pile bearing capacity, respectively; both the pile tip friction resistance and pile side friction resistance can be fully played, and reach to the design requirements. The reasonability of large diameter rock-socketed filling design is verified through test analysis, which can provide basis for the optimization of high-pile wharf structural type, thus reducing the wharf project cost, and also providing reference for the similar large diameter rock-socketed filling piles of high-pile wharf at Inland River.

  3. The reactor Cabri; La pile cabri

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J.; Millot, J.P. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1964-07-01

    exceptional circumstances... - experimental investigations on power excursions linked with precise initial conditions: the aim of this work is to define the basis for theoretical research, and the limits beyond which the risks of explosion cease to be negligible. The research work will be done so as to enable checking with outside reactor experiments and to continue them in the explosion field. - studies of the behaviour of the reactor control-instrumentation. - experimental investigations related with transient operation with initial short life (study of boiling, temperature measurements, vacuum pressure and fraction...) with the aim of defining the hypotheses of a theory on swimming-pool reactor kinetics related to heat transfer phenomena, - investigations of the behaviour of fuels in reactors (these experiments are planned to be carried out in loops) Preliminary experimental results. CABRI went critical on the 21 December 1963. The first transient experiments are expected for March 1964. (authors) [French] II devenait necessaire de construire en France une pile qui permette d'etudier les conditions de fonctionnement des installations futures, de choisir, tester et mettre au point les dispositifs de securite a adopter. On a choisi une pile a eau, type de pile qui correspond aux constructions les plus nouvelles du CEA en matiere de piles laboratoire ou d'universite; il importe en effet de pouvoir evaluer les risques presentes et d'etudier les possibilites d'augmentation de puissance constamment demandees par les utilisateurs: il est particulierement interessant d'eclaircir les phenomenes d'oscillation de puissance et les risques de calefaction (burn out). Les programmes de travaux sur CABRI seront harmonises avec les travaux effectues sur les Spert americains de meme type; lors de sa construction des contacts fructueux ont ete etablis avec les specialistes americains qui ont defini les premiers de ces reacteurs. La communication donne une

  4. Development of p-y curves of laterally loaded piles in cohesionless soil.

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2014-01-01

    The research on damages of structures that are supported by deep foundations has been quite intensive in the past decade. Kinematic interaction in soil-pile interaction is evaluated based on the p-y curve approach. Existing p-y curves have considered the effects of relative density on soil-pile interaction in sandy soil. The roughness influence of the surface wall pile on p-y curves has not been emphasized sufficiently. The presented study was performed to develop a series of p-y curves for single piles through comprehensive experimental investigations. Modification factors were studied, namely, the effects of relative density and roughness of the wall surface of pile. The model tests were subjected to lateral load in Johor Bahru sand. The new p-y curves were evaluated based on the experimental data and were compared to the existing p-y curves. The soil-pile reaction for various relative density (from 30% to 75%) was increased in the range of 40-95% for a smooth pile at a small displacement and 90% at a large displacement. For rough pile, the ratio of dense to loose relative density soil-pile reaction was from 2.0 to 3.0 at a small to large displacement. Direct comparison of the developed p-y curve shows significant differences in the magnitude and shapes with the existing load-transfer curves. Good comparison with the experimental and design studies demonstrates the multidisciplinary applications of the present method.

  5. Development of p-y Curves of Laterally Loaded Piles in Cohesionless Soil

    Science.gov (United States)

    Khari, Mahdy; Kassim, Khairul Anuar; Adnan, Azlan

    2014-01-01

    The research on damages of structures that are supported by deep foundations has been quite intensive in the past decade. Kinematic interaction in soil-pile interaction is evaluated based on the p-y curve approach. Existing p-y curves have considered the effects of relative density on soil-pile interaction in sandy soil. The roughness influence of the surface wall pile on p-y curves has not been emphasized sufficiently. The presented study was performed to develop a series of p-y curves for single piles through comprehensive experimental investigations. Modification factors were studied, namely, the effects of relative density and roughness of the wall surface of pile. The model tests were subjected to lateral load in Johor Bahru sand. The new p-y curves were evaluated based on the experimental data and were compared to the existing p-y curves. The soil-pile reaction for various relative density (from 30% to 75%) was increased in the range of 40–95% for a smooth pile at a small displacement and 90% at a large displacement. For rough pile, the ratio of dense to loose relative density soil-pile reaction was from 2.0 to 3.0 at a small to large displacement. Direct comparison of the developed p-y curve shows significant differences in the magnitude and shapes with the existing load-transfer curves. Good comparison with the experimental and design studies demonstrates the multidisciplinary applications of the present method. PMID:24574932

  6. Development of p-y Curves of Laterally Loaded Piles in Cohesionless Soil

    Directory of Open Access Journals (Sweden)

    Mahdy Khari

    2014-01-01

    Full Text Available The research on damages of structures that are supported by deep foundations has been quite intensive in the past decade. Kinematic interaction in soil-pile interaction is evaluated based on the p-y curve approach. Existing p-y curves have considered the effects of relative density on soil-pile interaction in sandy soil. The roughness influence of the surface wall pile on p-y curves has not been emphasized sufficiently. The presented study was performed to develop a series of p-y curves for single piles through comprehensive experimental investigations. Modification factors were studied, namely, the effects of relative density and roughness of the wall surface of pile. The model tests were subjected to lateral load in Johor Bahru sand. The new p-y curves were evaluated based on the experimental data and were compared to the existing p-y curves. The soil-pile reaction for various relative density (from 30% to 75% was increased in the range of 40–95% for a smooth pile at a small displacement and 90% at a large displacement. For rough pile, the ratio of dense to loose relative density soil-pile reaction was from 2.0 to 3.0 at a small to large displacement. Direct comparison of the developed p-y curve shows significant differences in the magnitude and shapes with the existing load-transfer curves. Good comparison with the experimental and design studies demonstrates the multidisciplinary applications of the present method.

  7. PROCESS DIAGRAMS FOR INSTALLATION OF DRIVEN PILES IN PENETRATED WELLS

    Directory of Open Access Journals (Sweden)

    Kovalev Vladimir Aleksandrovich

    2017-03-01

    Full Text Available This article presents the main options of improved and newly devised designs and process diagrams for installation of foundations made of driven, or jack, piles in the penetrated wells with expanded shoe, mainly in weak wet (waterlogged and water-saturated soils. The article presents six options of process diagrams for installation of driven piles in penetrated wells, listing the main procedures: for well-compacted weak soils, for the case when the water ingress is excluded, for the case when it is necessary to increase the load-bearing capacity of pile's bearing face in the waterlogged soils, for the case when the load-bearing capacity of the pile shall be increased both for the end and for the sides, for the case when peat or other biogenous water-saturated soils are present at the bottom of the well, and for the case when there is no contracted zone nor practical possibility to ensure the stability of the walls. The proposed six options of process diagrams for installation of the driven piles in penetrated wells provide expansion of their area of application regarding the soil conditions, increase of load-bearing capacity, and possibility of using jack systems for driving the piles under conditions of dense urban development.

  8. Main issues of pile foundation at waterfront development and its prevention method

    Science.gov (United States)

    Manap, N.; Tan, K. Y.; Syahrom, N.

    2017-12-01

    Pile foundation is widely used in construction and building marine structures. This is because pile foundation is an important structure and should have long-term durability. However, in waterfront development, a lot of issues from the seawater should be considered distinctively because it consists of many problems that can affect the building structure especially the foundation of the building. Thus, a research should be conducted to identify issues of pile foundation at waterfront development and determine its prevention methods. The research was carried out through interviews with the developers and contractors from the projects of Lexis Hibiscus at Port Dickson, Negeri Sembilan and Redevelopment for Deep-Water Facilities at Quay 6 in Pasir Gudang, Johor, Malaysia. The objectives of this research are to identify issues of pile foundation and to determine the prevention methods of pile foundation issues at waterfront development. All respondents agreed that the main issues of pile foundations at waterfront development are the wave and tide condition. The prevention methods of the issue faced at waterfront development that are most frequently used for the pile foundation are coating system and concrete cover. This research is beneficial to all developers and contractors to ensure pile foundations at waterfront development can be protected by using the prevention methods.

  9. Geotechnical and water resource aspects of uranium mill tailings pile reclamation projects

    International Nuclear Information System (INIS)

    Caldwell, J.A.; Tackston, J.W.; Portillo, R.

    1986-01-01

    Design and construction work is currently in progress at more than twenty sites associated with the UMTRA Project - this involves final reclamation of the uranium mill tailings piles so that they are stable for at least 200 years and for up to 1000 years. Remedial action construction plans for the tailings piles involve detailed consideration of the present and possible future ground water and surface-water impacts of the pile. Since the stabilized pile is ultimately a major geotechnical structure, detailed consideration of the long-term resistance to erosion and containment of radioactive material is also required. A case history illustrates how the critical design criteria governing the remedial action activities at the various piles are applied to the pile at the Lakeview site to provide for long-term protection of the water resource and public health and safety

  10. Tension Tests On Bored Piles In Sand

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Clausen, Johan; Damkilde, Lars

    2006-01-01

    The lengths of the bored piles varied from 2 m to 6 m and all were of a diameter of 140 mm. The piles were tested to failure in tension and the load-displacement relations were recorded. The investigation has shown pronounced differences between the load bearing capacities obtained by different...... design methods. The methods proposed by Fleming et al. and Reese & O’Neill seem to produce the best match with the test results....

  11. Investigation of a North Sea oil platform drill cuttings pile

    International Nuclear Information System (INIS)

    Hartley, J.P.; Watson, T.N.

    1993-01-01

    A comprehensive study of the drill cuttings pile at North West Hutton was undertaken in August, 1992. Fifty one wells have been drilled in the field, mainly using mineral oil based drill fluids, with the cuttings discharged to sea. The cuttings pile was mapped using a 3D side scan sonar system and the periphery was defined by towed side scan sonar and gamma ray spectrometer surveys. The pile was cored by vibrocorer to a maximum depth of 2.35m. The cores were assessed geotechnically and subsampled for physical and chemical analyses. Environmental impact was investigated by grab sampling at 12 stations out to 7,500m, selected on the basis of cuttings distribution. The results are relevant to the corrosion and long-term environmental effects of oily cuttings piles, the remove/leave alone debate, and abandonment planning. The cores were subsampled for hydrocarbon, trace metals and sulphide content and grain size analysis. Metals analyses included identification of metal species to estimate bioavailability and implications of pile disturbance. Estimates of oil migration within the pile are made from correlation of the chemical analyses results with the drilling history, in particular the change from diesel to low toxicity base oil in 1984. Strong gradients were found in the faunal data which correlate well with the physical and chemical results. Dense populations of opportunists species were present adjacent to the platform, including a novel molluscan opportunist. This is the first comprehensive study of an oily cuttings pile and is a contribution to the debate on their long term impact and fate on abandonment

  12. Study of the light emitted in the moderation of a heavy-water pile; Etude de la lumiere emise dans le moderateur d'une pile a eau lourde

    Energy Technology Data Exchange (ETDEWEB)

    Breton, D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-06-15

    During the running of a reactor which uses water as a neutron moderator, a bluish light is seen to appear inside the liquid. A detailed study of this radiation, undertaken on the Fontenay-aux-Roses pile, has shown that the spectrum is identical with that which characterises the light produced by the Cerenkov effect. The light intensity as a function of the pile power grows exponentially as a function of time when the pile diverges, with a lifetime equal to that of the rise in power. An examination of the various particles present in the pile has led to the conclusion that only electrons with an energy greater than 260 keV con produce the Cerenkov light. The light source thus produced is about 2.10{sup 6} photons/cm{sup 2} of water, when the pile power equals 1 watt. (author) [French] Lors du fonctionnement d'un reacteur utilisant l'eau comme moderateur de neutrons, on constate l'apparition d'une lumiere bleutee au sein du liquide. Une etude approfondie de ce rayonnement, entreprise sur la pile Fontenay-aux-Roses a montre que le spectre est identique a celui caracterisant la lumiere produite par effet Cerenkov. L'intensite lumineuse en fonction de Ia puissance de la pile, lors d'une divergence croit exponentiellement en fonction du temps avec une periode egale a celle de la montee en puissance. L'examen des diverses particules presentes dans la pile a permis de conclure que seuls les electrons ayant une energie superieure a 260 keV peuvent produire la lumiere Cerenkov. La source lumineuse ainsi constituee est d'environ 2.10{sup 6} photons/cm{sup 2} d'eau, lorsque la puissance de la pile est egale a 1 watt. (auteur)

  13. Nondestructive methods of evaluating quality of wood in preservative-treated piles

    Science.gov (United States)

    Xiping. Wang; Robert J. Ross; John R. Erickson; John W. Forsman; Gary D. McGinnis; Rodney C. De Groot

    2000-01-01

    Stress-wave-based nondestructive evaluation methods were used to evaluate the potential quality and modulus of elasticity (MOE) of wood in used preservative-treated Douglas-fir and southern pine piles. Stress wave measurements were conducted on each pile section. Stress wave propagation speeds in the piles were then obtained to estimate their MOE. This was followed by...

  14. Seismic analysis of the pile foundation of the reactor building of the NPP ANGRA 2

    International Nuclear Information System (INIS)

    Wolf, J.P.; Arx, G.A. von; Barros, F.C.P. de; Kakubo, M.

    1981-01-01

    A pile foundation subjected to dynamic loads interacts with the surrounding soil. Frequency-dependent stiffness and radiation damping must be properly taken into account in pile-soil-pile interaction. Assuming that the soil consists of horizontal layers of elastic material with hysteretic damping, the dynamic stiffness of a group of (even battered) piles can be determined, accounting rigorously for the cavities where the soil is subsequently replaced by the piles. By way of illustration, this substructure procedure, which works in the frequency domain, is applied to the final design of the pile foundation of the Reactor Building of Angra 2 in Brazil. Below the basemat, a strongly horizontally-layered compressive soil of 36 m thickness rests on bedrock. The reactor building is founded on 202 endbearing piles and 88 floating piles of 15 m length. Every pile is modelled. Along each pile, compatibility between the pile and the soil in all three directions is formulated in seven nodes. The basemat is assumed to be rigid. On the level of bedrock a broad-banded response spectrum specifies the excitation (outcropping). (orig./WL)

  15. Airborne thermography of temperature patterns in sugar beet piles

    Science.gov (United States)

    Moore, D. G.; Bichsel, S.

    1975-01-01

    An investigation was conducted to evaluate the use of thermography for locating spoilage areas (chimneys) within storage piles and to subsequently use the information for the scheduling of their processing. Thermal-infrared quantitative scanner data were acquired initially on January 16, 1975, over the storage piles at Moorhead, Minnesota, both during the day and predawn. Photographic data were acquired during the day mission to evaluate the effect of uneven snow cover on the thermal emittance, and the predawn thermography was used to locate potential chimneys. The piles were examined the day prior for indications of spoilage areas, and the ground crew indicated that no spoilage areas were located using their existing methods. Nine spoilage areas were interpreted from the thermography. The piles were rechecked by ground methods three days following the flights. Six of the nine areas delineated by thermography were actual spoilage areas.

  16. Large scale vibration tests on pile-group effects using blast-induced ground motion

    International Nuclear Information System (INIS)

    Katsuichirou Hijikata; Hideo Tanaka; Takayuki Hashimoto; Kazushige Fujiwara; Yuji Miyamoto; Osamu Kontani

    2005-01-01

    Extensive vibration tests have been performed on pile-supported structures at a large-scale mining site. Ground motions induced by large-scale blasting operations were used as excitation forces for vibration tests. The main objective of this research is to investigate the dynamic behavior of pile-supported structures, in particular, pile-group effects. Two test structures were constructed in an excavated 4 m deep pit. Their test-structures were exactly the same. One structure had 25 steel piles and the other had 4 piles. The test pit was backfilled with sand of appropriate grain size distributions to obtain good compaction, especially between the 25 piles. Accelerations were measured at the structures, in the test pit and in the adjacent free field, and pile strains were measured. Dynamic modal tests of the pile-supported structures and PS measurements of the test pit were performed before and after the vibration tests to detect changes in the natural frequencies of the soil-pile-structure systems and the soil stiffness. The vibration tests were performed six times with different levels of input motions. The maximum horizontal acceleration recorded at the adjacent ground surface varied from 57 cm/s 2 to 1,683 cm/s 2 according to the distances between the test site and the blast areas. (authors)

  17. Numerical modeling of centrifuge cyclic lateral pile load experiments

    Science.gov (United States)

    Gerolymos, Nikos; Escoffier, Sandra; Gazetas, George; Garnier, Jacques

    2009-03-01

    To gain insight into the inelastic behavior of piles, the response of a vertical pile embedded in dry sand and subjected to cyclic lateral loading was studied experimentally in centrifuge tests conducted in Laboratoire Central des Ponts et Chaussées. Three types of cyclic loading were applied, two asymmetric and one symmetric with respect to the unloaded pile. An approximately square-root variation of soil stiffness with depth was obtained from indirect in-flight density measurements, laboratory tests on reconstituted samples, and well-established empirical correlations. The tests were simulated using a cyclic nonlinear Winkler spring model, which describes the full range of inelastic phenomena, including separation and re-attachment of the pile from and to the soil. The model consists of three mathematical expressions capable of reproducing a wide variety of monotonic and cyclic experimental p-y curves. The physical meaning of key model parameters is graphically explained and related to soil behavior. Comparisons with the centrifuge test results demonstrate the general validity of the model and its ability to capture several features of pile-soil interaction, including: soil plastification at an early stage of loading, “pinching” behavior due to the formation of a relaxation zone around the upper part of the pile, and stiffness and strength changes due to cyclic loading. A comparison of the p-y curves derived from the test results and the proposed model, as well as those from the classical curves of Reese et al. (1974) for sand, is also presented.

  18. The Influence of Time on Bearing Capacity of Driven Piles

    DEFF Research Database (Denmark)

    Jensen, J. Lysebjerg; Augustesen, A.; Sørensen, Carsten S.

    2004-01-01

    In Danish engineering practice, one of the ways to determine the ultimate bearing capacity of an axially loaded pile is by means of geostatic formulas. In the equation describing the contribution from the shaft friction to the total bearing capacity for piles located entirely or partly in clay......, a regeneration factor appears. The regeneration factor accounts for effects of dissipation of pore pressure due to pile driving and true time effects such as ageing on the ultimate bearing capacity. Normally the factor is 0.4 but in this paper, the influence of the undrained shear strength and time...... on the regeneration factor is investigated. A relation between the quantities is proposed, which in the end may imply an economical benefit in the design of pile foundations....

  19. Simulation analyses of vibration tests on pile-group effects using blast-induced ground motions

    International Nuclear Information System (INIS)

    Takayuki Hashimoto; Kazushige Fujiwara; Katsuichirou Hijikata; Hideo Tanaka; Kohji Koyamada; Atsushi Suzuki; Osamu Kontani

    2005-01-01

    Extensive vibration tests have been performed on pile-supported structures at a large-scale mining site to promote better understanding of the dynamic behavior of pile-supported structures, especially pile-group effects. Two test structures were constructed in an excavated pit. One structure was supported on 25 tubular steel piles and the other on 4. The test pit was backfilled with sand of an appropriate grain size distribution to ensure good compaction. Ground motions induced by large-scale blasting operations were used as excitation forces for the tests. The 3D Finite Element Method (3D FEM)and a Genetic Algorithm (GA) were employed to identify the shear wave velocities and damping factors of the compacted sand, especially of the surface layer. A beam-interaction spring model was employed to simulate the test results of the piles and the pile-supported structures. The superstructure and pile foundation were modeled by a one-stick model comprising lumped masses and beam elements. The pile foundations were modeled just as they were, with lumped masses and beam elements to simulate the test results showing that, for the 25-pile structure, piles at different locations showed different responses. It was confirmed that the analysis methods employed were very useful for evaluating the nonlinear behavior of the soil-pile-structure system, even under severe ground motions. (authors)

  20. Stress transfer from pile group in saturated and unsaturated soil using theoretical and experimental approaches

    Directory of Open Access Journals (Sweden)

    al-Omari Raid R.

    2017-01-01

    Full Text Available Piles are often used in groups, and the behavior of pile groups under the applied loads is generally different from that of single pile due to the interaction of neighboring piles, therefore, one of the main objectives of this paper is to investigate the influence of pile group (bearing capacity, load transfer sharing for pile shaft and tip in comparison to that of single piles. Determination of the influence of load transfer from the pile group to the surrounding soil and the mechanism of this transfer with increasing the load increment on the tip and pile shaft for the soil in saturated and unsaturated state (when there is a negative pore water pressure. Different basic properties are used that is (S = 90%, γd = 15 kN / m3, S = 90%, γd = 17 kN / m3 and S = 60%, γd =15 kN / m3. Seven model piles were tested, these was: single pile (compression and pull out test, 2×1, 3×1, 2×2, 3×2 and 3×3 group. The stress was measured with 5 cm diameter soil pressure transducer positioned at a depth of 5 cm below the pile tip for all pile groups. The measured stresses below the pile tip using a soil pressure transducer positioned at a depth of 0.25L (where L is the pile length below the pile tip are compared with those calculated using theoretical and conventional approaches. These methods are: the conventional 2V:1H method and the method used the theory of elasticity. The results showed that the method of measuring the soil stresses with soil pressure transducer adopted in this study, gives in general, good results of stress transfer compared with the results obtained from the theoretical and conventional approaches.

  1. Lateral resistance of piles near vertical MSE abutment walls.

    Science.gov (United States)

    2013-03-01

    Full scale lateral load tests were performed on eight piles located at various distances behind MSE walls. The objective of the testing was to determine the effect of spacing from the wall on the lateral resistance of the piles and on the force induc...

  2. A prospective study of outcome from rubber band ligation of piles.

    Science.gov (United States)

    Longman, R J; Thomson, W H F

    2006-02-01

    With the recent introduction of stapled anopexy it is timely to review the benefits of existing treatment options for piles. This study investigates the effectiveness and safety of rubber band ligation (RBL) of piles in the outpatient setting. Two hundred and fifty-two consecutive patients referred with piles in an 18-month period were studied prospectively. In those patients deemed suitable for banding of piles, data were collected on symptoms, proctoscopic appearance and degree of piles. Short and long-term outcome data were recorded for success of treatment and complications. Of 203 patients considered suitable and who attended for RBL, 176 kept their follow-up appointment. One hundred and forty-eight (84%) had been rendered symptom-free. A third of patients, however, had proctoscopic evidence of persistent piles, whilst in half of those patients with continuing symptoms the anal cushions appeared normal. Six (3%) patients had suffered a complication. Long-term follow-up by questionnaire found that 44% of respondents remained asymptomatic at a median of 46 months from banding. Six (5%) of 117 responders to the questionnaire had, though previously normal, suffered a postbanding impairment of continence. Most patients with piles of any degree can be safely managed by rubber band ligation, but return of symptoms in the long term affects more than half of patients treated.

  3. Gas reactor in-pile safety test project (GRIST-2)

    International Nuclear Information System (INIS)

    Kelley, A.P. Jr.; Arbtin, E.; St Pierre, R.

    1979-01-01

    Although out-of-pile tests may be expected to confirm individual phenomena models in core disruptive accident analysis codes, only in-pile tests are capable of verifying the extremely complex integrated model effects within the appropriate time phase for these accidents. For this reason, the GRIST-2 project, the purpose of which is to design and construct an in-pile helium loop capable of transient safety testing in the TREAT facility in Idaho, forms a cornerstone of the US GCFR safety program. The project organization, experiment program, facility, helium system design, and schedule which have been selected to meet the objectives are described

  4. Multi-scale sensitivity analysis of pile installation using DEM

    Science.gov (United States)

    Esposito, Ricardo Gurevitz; Velloso, Raquel Quadros; , Eurípedes do Amaral Vargas, Jr.; Danziger, Bernadete Ragoni

    2017-12-01

    The disturbances experienced by the soil due to the pile installation and dynamic soil-structure interaction still present major challenges to foundation engineers. These phenomena exhibit complex behaviors, difficult to measure in physical tests and to reproduce in numerical models. Due to the simplified approach used by the discrete element method (DEM) to simulate large deformations and nonlinear stress-dilatancy behavior of granular soils, the DEM consists of an excellent tool to investigate these processes. This study presents a sensitivity analysis of the effects of introducing a single pile using the PFC2D software developed by Itasca Co. The different scales investigated in these simulations include point and shaft resistance, alterations in porosity and stress fields and particles displacement. Several simulations were conducted in order to investigate the effects of different numerical approaches showing indications that the method of installation and particle rotation could influence greatly in the conditions around the numerical pile. Minor effects were also noted due to change in penetration velocity and pile-soil friction. The difference in behavior of a moving and a stationary pile shows good qualitative agreement with previous experimental results indicating the necessity of realizing a force equilibrium process prior to any load-test to be simulated.

  5. Cascades of pile-up and dead time

    International Nuclear Information System (INIS)

    Pomme, S.

    2008-01-01

    Count loss through a cascade of pile-up and dead time is studied. Time interval density-distribution functions and throughput factors are presented for counters with a series arrangement of pile-up and extending or non-extending dead time. A counter is considered, where an artificial dead time is imposed on every counted event, in order to control the length and type of dead time. For such a system, it is relatively easy to determine an average count-loss correction factor via a live-time clock gated by the imposed dead-time signal ('live-time mode'), or otherwise to apply a correction factor based on the inversion of the throughput function ('real-time mode'). However, these techniques do not account for additional loss through pulse pile-up. In this work, counting errors associated with neglecting cascade effects are calculated for measurements in live-time and real-time mode

  6. Investigation of Redistribution of Pile Foundation Forces Under Successive Loading of Its Elements

    Science.gov (United States)

    Sedin, Vladimir; Bikus, Kateryna; Kovba, Vladislav

    2017-12-01

    Redistribution of pile foundation forces under successive loading of its elements was investigated under laboratory conditions. A segment of pile foundation model was taken for use in the case study. Load tests on the pile foundation model segment, without joining its elements (pile and plate, which turns into grillage) and based on different combinations of static loadings were conducted. This proved that the loading of a plate causes skin friction on some length of the pile side surface as well as providing additional loading and settlement. Test results have shown that application of successive elements enables the foundation to carry loads up to 13% higher than in the case of a standard pile foundation loading with the same settlement rates.

  7. In-pile creep strain and failure of CW 316 Ti pressurized tubes

    International Nuclear Information System (INIS)

    Boutard, J.L.; Maillard, A.; Carteret, Y.; Levy, V.; Meny, L.

    1984-06-01

    The in-pile creep and failure behavior of CW 316 Ti pressurized tubes irradiated in the same rig at 660-680 0 C and 81.4 dpaF max in Phenix is presented and compared to monitors of the same heat. The in-pile plastic strains are of the same order of what is expected from the monitors and are rather independent of the dose rate in the range 4 to 9 x 10 -3 dpaF/h. Such a behavior supports the assumption that the out-of-pile deformation mechanisms are operative in pile and a certain balance occurs between modification of the microstructure, dynamic hardening and deformation mechanisms due to irradiation. Examinations by fractography and optical micrography, show that the failures are intergranular either in-pile or out-of-pile. In both cases the damage consists in intergranular wedge cracks, and no cavitation can be observed by transmission electron microscopy. Then the in-pile embrittlement which gives lower failure strain and time is to be associated with a decrease of the surface energy of grain-boundaries rather then growth and coalescence of cavities

  8. Bulk density and porosity distributions in a compost pile

    NARCIS (Netherlands)

    Ginkel, van J.T.; Raats, P.A.C.; Haneghem, van I.A.

    1999-01-01

    This paper mainly deals with the description of the initial distribution of bulk density and porosity at the moment a compost pile is built or rebuilt. A relationship between bulk density and vertical position in a pile is deduced from theoretical and empirical considerations. Formulae to calculate

  9. Acoustic emission diagnosis of concrete-piles damaged by earthquakes

    International Nuclear Information System (INIS)

    Shiotami, Tomoki; Sakaino, Norio; Ohtsu, Masayasu; Shigeishi, Mitsuhiro

    1997-01-01

    Earthquakes often impose unexpected damage on structures. Concerning the soundness of the structure, the upper portion is easily estimated by visual observation, while the lower portion located in deep underground is difficult to be estimated. Thus there exist few effective methods to investigate underground structures. In this paper, a new inspection technique for damage evaluation of concrete-piles utilizing acoustic emission (AE) is proposed, and is verified by a series of experiments. Firstly, such basic characteristics as the attenuation and effective wave-guides for detecting AE underground, are examined through laboratory tests. Secondary, fracture tests of full-scale prefabricated concrete piles are conducted, and the characteristics of the AE are examined. Finally, actual concrete-piles attacked by the 1995 Great Hanshin Earthquake are investigated. Results confirm that the estimated damages by the proposed method are in good agreement with actual damaged locations. Thus, the method is very effective for the diagnosis of the concrete-piles.

  10. Improved Design Basis for Laterally Loaded Large Diameter Pile

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    of up-to-date facilities has been: Equipment for controlling centrifuge tests, data acquisition, preparation of test samples and equipment for and making of lateral load tests. The present research has been narrowed to investigate the static and cyclic behaviour of stiff piles with a diameter of 1-3 m...... in dry sand by use of centrifuge modelling and to compare the findings with the standard p-y curves. It has been chosen to apply piles with an embedment length of 6 to 10 times the diameter of the applied piles. The general static behaviour of monopiles in dry sand has based on centrifuge tests been...... with a capacity of 3.6 MW and placed at water depths beyond 25 m. Different foundation solutions have over the years been applied for offshore turbines, but monopiles are currently the most applied foundation type and are typically with a pile diameter of 4-6 m and applied up to a water depth of 25 m...

  11. Heterogeneous dipolar theory of the exponential pile

    International Nuclear Information System (INIS)

    Mastrangelo, P.V.

    1981-01-01

    We present a heterogeneous theory of the exponential pile, closely related to NORDHEIM-SCALETTAR's. It is well adapted to lattice whose pitch is relatively large (D-2O, grahpite) and the dimensions of whose channels are not negligible. The anisotropy of neutron diffusion is taken into account by the introduction of dipolar parameters. We express the contribution of each channel to the total flux in the moderator by means of multipolar coefficients. In order to be able to apply conditions of continuity between the flux and their derivatives, on the side of the moderator, we develop in a Fourier series the fluxes found at the periphery of each channel. Using Wronski's relations of Bessel's functions, we express the multipolar coefficients of the surfaces of each channel, on the side of the moderator, by means of the harmonics of each flux and their derivatives. We retain only monopolar (A 0 sub(g)) and dipolar (A 1 sub(g)) coefficients; those of a higher order are ignored. We deduce from these coefficients the systems of homogeneous equations of the exponential pile with monopoles on their own and monopoles plus dipoles. It should be noted that the systems of homogeneous equations of the critical pile are contained in those of the exponential pile. In another article, we develop the calculation of monopolar and dipolar heterogeneous parameters. (orig.)

  12. Three-dimensional analysis for piled raft machine foundation embedded in sand

    Directory of Open Access Journals (Sweden)

    Mahmood Mahmood

    2018-01-01

    Full Text Available Three-dimensional analysis for the dynamic response of a piled raft foundation subjected to vertical vibration is presented in this study. The analysis considers several factors affecting the amplitude of displacement for deep foundation such as pile cap embedment, pile cap thickness, relative density of the sand and the boundary effect. A validation for an experimental piled raft model depending on a scale factor of (20 using at (Plaxis 3D computer program was performed. The sand is simulated using Mohr-Coloumb model while the concrete is simulated as linear elastic material. It has been found that embedding the pile cap in the soil and increasing its thickness lead to decrease the maximum amplitude of displacement. Furthermore, the predictions showed that increasing the distance between the foundation and the boundaries and increasing the relative density of the sand can significantly minimize the dynamic response of the foundation.

  13. Preliminary report on coal pile, coal pile runoff basins, and ash basins at the Savannah River Site: effects on groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1997-04-28

    Coal storage piles, their associated coal pile runoff basins and ash basins could potentially have adverse environmental impacts, especially on groundwater. This report presents and summarizes SRS groundwater and soil data that have been compiled. Also, a result of research conducted on the subject topics, discussions from noted experts in the field are cited. Recommendations are made for additional monitor wells to be installed and site assessments to be conducted.

  14. ANALYSIS OF EXISTING SCHEMES AND THE OPTIMIZING SETTLEMENT CHOIS OF PILES WORK SCHEMES IN CLAY SOILS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2016-09-01

    Full Text Available Summary. It were considered and analyzed the existing schemes of piles work in clay soils. 1. Leningrad scientific school, where the formation of pile bearing capacity use as the basis of the thixotropic clay soils hardening and radial soil pressing around the pile shaft during the piles driving with pile-driving equipment for the exploitation period. 2. Odessa scientific school, in which the uplift soil formation from the edge pile use as the basis of the pile bearing capacity during the piles driving, the formation of the pressed zones (platform in the piles edge plane, the gap formation around the pile shaft during its diving by ground pushed moving with the pile edge. 3. Preconditions of the pile bearing capacity formation of the pile by the thixotropic soil hardening in time and the radial soil pressing around the pile shaft can not give an answer to the following questions: 1 Why during the pile driving is formed the gap around the trunk of dived piles, when by condition there is a radial soil hardening around the trunk? 2 Why in the interpiled space is formed the lune (deflection, not the soil mass swelling (due to the radial hardening? 3 By what is formed the calculated soil resistance under the lower end (edge of the pile? which is about 10 times higher than the calculated soil resistance in the edge plane, according to the Building Code V.2.1-10. 2009? The justified answers on all these and other technical and technological matters give perquisites of the Odessa scientific school with additions and authors developments

  15. Dynamic load testing on the bearing capacity of prestressed tubular concrete piles in soft ground

    Science.gov (United States)

    Yu, Chuang; Liu, Songyu

    2008-11-01

    Dynamic load testing (DLT) is a high strain test method for assessing pile performance. The shaft capacity of a driven PTC (prestressed tubular concrete) pile in marine soft ground will vary with time after installation. The DLT method has been successfully transferred to the testing of prestressed pipe piles in marine soft clay of Lianyungang area in China. DLT is investigated to determine the ultimate bearing capacity of single pile at different period after pile installation. The ultimate bearing capacity of single pile was founded to increase more than 70% during the inventing 3 months, which demonstrate the time effect of rigid pile bearing capacity in marine soft ground. Furthermore, the skin friction and axial force along the pile shaft are presented as well, which present the load transfer mechanism of pipe pile in soft clay. It shows the economy and efficiency of DLT method compared to static load testing method.

  16. Optimal Pile Arrangement for Minimizing Excess Pore Water Pressure Build-Up

    DEFF Research Database (Denmark)

    Barari, Amin; Saadati, Meysam; Ibsen, Lars Bo

    2013-01-01

    Numerical analysis of pile group in a liquefiable soil was considered to investigate the influence of pile spacing on excess pore pressure distribution and liquefaction potential. The analysis is conducted using a two-dimensional plain strain finite difference program considering a nonlinear...... constitutive model for sandy soil, strength and stiffness reduction, and pile-soil interaction. The Mohr-Coulomb constitutive model coupled with Byrne pore pressure build-up model have been employed in the analysis. Numerical analysis results show that pile groups have significant influence on the dynamic...... response of sandy soil as they reduce the amount of excess pore pressure development during seismic shaking and may even prevent liquefaction....

  17. Reheating experiment in the 35-ton pile; Experience de rechauffage sur la pile de 35 tonnes

    Energy Technology Data Exchange (ETDEWEB)

    Cherot, J; Girard, Y [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    When the 35-ton pile was started up it was necessary for us, in order to study certain effects (xenon for example), to know the anti reactivity value of the rods as a function of their dimensions. We have made use of the possibility, in the reheating experiment, of raising the temperature of the graphite-uranium block by simple heating, in order to determine the anti reactivity curves of the rods, and from that the overall temperature coefficient. For the latter we have considered two solutions: first, one in which the average temperature of the pile is defined as our arithmetical mean of the different values given by the 28 thermocouples distributed throughout the pile; a second in which the temperature in likened to a poisoning and is balanced by the square of the flux. The way in which the measurements have been made is indicated, and the different instruments used are described. The method of reheating does not permit the separation of the temperature coefficients of uranium and of graphite. The precision obtained is only moderate, and suffers from the changes of various parameters necessary to other manipulations carried out simultaneously (life time modulators for example), and finally it is a function of the comparatively restricted time allowed. It is evident of course that more careful stabilisation at the different plateaux chosen would have necessitated long periods of reheating. (author) [French] Nous avions besoin lors de la montee en puissance de la pile de 35 tonnes, pour l'elude de divers effets (xenon par ex.) de la valeur de l'antireactivite des barres en fonction de leurs cotes. Nous avons profite dans l'experience rechauffage de la possibilite de monter en temperature, non nucleairement, le bloc graphite uranium, pour determiner les courbes d'antireactivite des barres et de la le coefficient global de temperature. Nous avons considere pour ce dernier deux solutions. Une premiere dans laquelle la temperature moyenne de la pile est definie comme

  18. Thermal response test data of five quadratic cross section precast pile heat exchangers.

    Science.gov (United States)

    Alberdi-Pagola, Maria

    2018-06-01

    This data article comprises records from five Thermal Response Tests (TRT) of quadratic cross section pile heat exchangers. Pile heat exchangers, typically referred to as energy piles, consist of traditional foundation piles with embedded heat exchanger pipes. The data presented in this article are related to the research article entitled "Comparing heat flow models for interpretation of precast quadratic pile heat exchanger thermal response tests" (Alberdi-Pagola et al., 2018) [1]. The TRT data consists of measured inlet and outlet temperatures, fluid flow and injected heat rate recorded every 10 min. The field dataset is made available to enable model verification studies.

  19. Study of the light emitted in the moderation of a heavy-water pile; Etude de la lumiere emise dans le moderateur d'une pile a eau lourde

    Energy Technology Data Exchange (ETDEWEB)

    Breton, D. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-06-15

    During the running of a reactor which uses water as a neutron moderator, a bluish light is seen to appear inside the liquid. A detailed study of this radiation, undertaken on the Fontenay-aux-Roses pile, has shown that the spectrum is identical with that which characterises the light produced by the Cerenkov effect. The light intensity as a function of the pile power grows exponentially as a function of time when the pile diverges, with a lifetime equal to that of the rise in power. An examination of the various particles present in the pile has led to the conclusion that only electrons with an energy greater than 260 keV con produce the Cerenkov light. The light source thus produced is about 2.10{sup 6} photons/cm{sup 2} of water, when the pile power equals 1 watt. (author) [French] Lors du fonctionnement d'un reacteur utilisant l'eau comme moderateur de neutrons, on constate l'apparition d'une lumiere bleutee au sein du liquide. Une etude approfondie de ce rayonnement, entreprise sur la pile Fontenay-aux-Roses a montre que le spectre est identique a celui caracterisant la lumiere produite par effet Cerenkov. L'intensite lumineuse en fonction de Ia puissance de la pile, lors d'une divergence croit exponentiellement en fonction du temps avec une periode egale a celle de la montee en puissance. L'examen des diverses particules presentes dans la pile a permis de conclure que seuls les electrons ayant une energie superieure a 260 keV peuvent produire la lumiere Cerenkov. La source lumineuse ainsi constituee est d'environ 2.10{sup 6} photons/cm{sup 2} d'eau, lorsque la puissance de la pile est egale a 1 watt. (auteur)

  20. Study on Dynamic Characteristics of Heavy Machine Tool-Composite Pile Foundation-Soil

    Directory of Open Access Journals (Sweden)

    CAI Li-Gang

    2014-09-01

    Full Text Available Heavy duty computer numerical control machine tools have characteristics of large self-weight, load and. The insufficiency of foundation bearing capacity leads to deformation of lathe bed, which effects machining accuracy. A combined-layer foundation model is created to describe the pile group foundation of multi-soil layer in this paper. Considering piles and soil in pile group as transversely isotropic material, equivalent constitutive relationship of composite foundation is constructed. A mathematical model is established by the introduction of boundary conditions, which is based on heavy duty computer numerical control machine tools-composite pile foundation-soil interaction system. And then, the response of different soil and pile depth is studied by a case. The model improves motion accuracy of machine tools.

  1. Smart pile-up consideration for evaluation of high count rate EDS spectra

    International Nuclear Information System (INIS)

    Eggert, F; Anderhalt, R; Nicolosi, J; Elam, T

    2012-01-01

    This work describes a new pile-up consideration for the very high count rate spectra which are possible to acquire with silicon drift detector (SDD) technology. Pile-up effects are the major and still remaining challenge with the use of SDD for EDS in scanning electron microscopes (SEM) with ultra thin windows for soft X-ray detection. The ability to increase the count rates up to a factor of 100 compared with conventional Si(Li) detectors, comes with the problem that the pile-up recognition (pile-up rejection) in pulse processors is not able to improve by the same order of magnitude, just only with a factor of about 3. Therefore, it is common that spectra will show significant pile-up effects if count rates of more than 10000 counts per second (10 kcps) are used. These false counts affect both automatic qualitative analysis and quantitative evaluation of the spectra. The new idea is to use additional inputs for pile-up calculation to shift the applicability towards very high count rates of up to 200 kcps and more, which can be easily acquired with the SDD. The additional input is the 'known' (estimated) background distribution, calculated iteratively during all automated qualitative or quantitative evaluations. This additional knowledge gives the opportunity for self adjustment of the pile-up calculation parameters and avoids over-corrections which challenge the evaluation as well as the pile-up artefacts themselves. With the proposed method the pile-up correction is no longer a 'correction' but an integral part of all spectra evaluation steps. Examples for the application are given with evaluation of very high count rate spectra.

  2. Placement of mass concrete for cast-in-place concrete piling : the effects of heat of hydration of mass concrete for cast-in-place piles.

    Science.gov (United States)

    2008-12-01

    This report describes models, ABAQUS and Schmidt, to predict the peak temperature in the center of cast-in-place concrete piling. Five concrete piles with varying diameters and made up of concrete mixes with different percentage of fly ash are used. ...

  3. The Use of Tactile Sensors and PIV Analysis for Understanding the Bearing Mechanism of Pile Groups.

    Science.gov (United States)

    You, Zhijia; Chen, Yulong

    2018-02-06

    Model tests were carried out in dry silica sand under pile loading and visualizing observation to investigate the behavior of a pile group. The pile group consisted of nine cylindrical model piles of 40 mm in diameter in most tests or three rectangular parallelepiped model piles in the visualizing observation. Pile spacings of 200 mm and 100 mm between pile centers were used in the models. Tactile sensors were installed to measure the pressure distribution in the ground and colored sand layer with particle image velocimetry (PIV) analysis to reveal the ground deformation in addition to strain gauges inside the model piles to investigate the interaction among group piles. The tests results showed that a narrower spacing between piles resulted in a wider affected area of the ground and the interaction was more significant below the tips.

  4. Subsurface barrier design alternatives for confinement and controlled advection flow

    International Nuclear Information System (INIS)

    Phillips, S.J.; Stewart, W.E.; Alexander, R.G.; Cantrell, K.J.; McLaughlin, T.J.

    1994-02-01

    Various technologies and designs are being considered to serve as subsurface barriers to confine or control contaminant migration from underground waste storage or disposal structures containing radioactive and hazardous wastes. Alternatives including direct-coupled flood and controlled advection designs are described as preconceptual examples. Prototype geotechnical equipment for testing and demonstration of these alternative designs tested at the Hanford Geotechnical Development and Test Facility and the Hanford Small-Tube Lysimeter Facility include mobile high-pressure injectors and pumps, mobile transport and pumping units, vibratory and impact pile drivers, and mobile batching systems. Preliminary laboratory testing of barrier materials and additive sequestering agents have been completed and are described

  5. Seismological analysis of group pile foundation for reactor

    International Nuclear Information System (INIS)

    Wang Demin.

    1984-01-01

    In the seismic analysis for reactor foundation of nuclear power plant, the local raise of base mat is of great significance. Base on the study of static and dynamic stability as well as soil-structure interaction of group piles on stratified soil, this paper presents a method of seismic analysis for group piles of reactor foundation at abroad, and a case history is enclosed. (Author)

  6. THE RELIABILITY ANALYSIS OF EXISTING REINFORCED CONCRETE PILES IN PERMAFROST REGIONS

    Directory of Open Access Journals (Sweden)

    Vladimir S. Utkin

    2017-06-01

    Full Text Available The article describes the general problem of safe operation of buildings and structures with the dynamics of permafrost in Russia and other countries. The global warming on Earth will lead to global disasters such as failures of buildings and structures. The main reason of these failures will be a reduction of bearing capacity and the reliability of foundations. It is necessary to organize the observations (monitoring for the process of reducing the bearing capacity of foundations to prevent such accidents and reduce negative consequences, to development of preventive measures and operational methods for the piles reliability analysis. The main load-bearing elements of the foundation are reinforced concrete piles and frozen ground. Reinforced concrete piles have a tendency to decrease the bearing capacity and reliability of the upper (aerial part and the part in the soil. The article discusses the problem of reliability analysis of existing reinforced concrete piles in upper part in permafrost regions by the reason of pile degradation in the contact zone of seasonal thawing and freezing soil. The evaluation of the probability of failure is important in itself, but also it important for the reliability of foundation: consisting of piles and frozen soil. Authors offers the methods for reliability analysis of upper part of reinforced concrete piles in the contact zone with seasonally thawed soil under different number of random variables (fuzzy variables in the design mathematical model of a limit state by the strength criterion.

  7. The architecture of tholeiitic lava flows in the Neogene flood basalt piles of eastern Iceland: constraints on the mode of emplacemement

    Science.gov (United States)

    Oskarsson, B. V.; Riishuus, M. S.

    2012-12-01

    Tholeiites comprise 50-70% of the Neogene lava piles of eastern Iceland and have been described largely as flood basalts erupted from fissures (Walker, 1958). This study incorporates lava piles found in the Greater Reydarfjördur area and emprises the large-scale architecture of selected flows and flow groups, their internal structure and textures with the intention of assessing their mode of emplacement. A range of lava morphologies have been described and include: simple (tabular) flows with a'a and rubbly flow tops, simple flows with pahoehoe crust and compound pahoehoe flows, with simple flows being most common. Special attention is given here to the still poorly understood simple flows, which are characterized by extensive sheet lobes with individual sheet lengths frequently exceeding 2 km and reaching thicknesses of ~40 m (common aspect ratios The sheets in individual flow fields are emplaced side by side with an overlapping contact and are free of tubes. Their internal structure generally constitutes an upper vesicular crust with no or minor occurrences of horizontal vesicle zones, a poorly vesicular core and a thin basal vesicular zone. The normalized core/crust thickness ratios resemble modern compound pahoehoe flows in many instances (0.4-0.7), but with the thicker flows reaching ratios of 0.9. Flow crusts are either pahoehoe, rubbly or scoriaceous with torn and partially welded scoria and clinker. Frequently, any given flow morphology is repeated in sequences of three to four flows with direct contacts. Preliminary assessments suggest that simple flows are the product of high and sustained effusion rates from seemingly short-lived fissures. Simple flows with a'a flow tops may comprise the annealed emplacement mode of sheet flows and channeled a'a, in which the flow propagated as a single unit, whereas the brecciated flow top formed by continuous tearing and brecciation as occurs in channeled lava flowing at high velocity. The absence of a clinkery basal

  8. Analysis of Bearing Capacity Pile Foundation with Using Capwap Software for Testing Pile Driving Analyzer (pda) at Fasfel Development Project Parlimbungan Ketek Sikara-Kara Mandailing Natal District (north Sumatera)

    Science.gov (United States)

    Oberlyn Simanjuntak, Johan; Suita, Diana

    2017-12-01

    Pile foundation is one type deep foundation that serves to distribute the load of hard soil structure loading which has a high bearing capacity that is located deep enough inside the soil. To determine the bearing capacity of the pile and at the same time control the Calendring results, the Pile Driving Analyzer (PDA) test at 8 pile sections from the 84 point piling section (10% of the number sections), the results were analyzed by CAPWAP SOFTWARE, and the highest bearing capacity of Ru 177 ton and the lowest bearing capacity of 111 tons, is bigger than the plan load which load plans that is 60,9 tons. Finally the PDA safe is bearing bearing capacity of the load planning.

  9. Picking up Clues from the Discard Pile (Stereo)

    Science.gov (United States)

    2008-01-01

    As NASA's Phoenix Mars Lander excavates trenches, it also builds piles with most of the material scooped from the holes. The piles, like this one called 'Caterpillar,' provide researchers some information about the soil. On Aug. 24, 2008, during the late afternoon of the 88th Martian day after landing, Phoenix's Surface Stereo Imager took separate exposures through its left eye and right eye that have been combined into this stereo view. The image appears three dimensional when seen through red-blue glasses. This conical pile of soil is about 10 centimeters (4 inches) tall. The sources of material that the robotic arm has dropped onto the Caterpillar pile have included the 'Dodo' and ''Upper Cupboard' trenches and, more recently, the deeper 'Stone Soup' trench. Observations of the pile provide information, such as the slope of the cone and the textures of the soil, that helps scientists understand properties of material excavated from the trenches. For the Stone Soup trench in particular, which is about 18 centimeters (7 inches) deep, the bottom of the trench is in shadow and more difficult to observe than other trenches that Phoenix has dug. The Phoenix team obtained spectral clues about the composition of material from the bottom of Stone Soup by photographing Caterpillar through 15 different filters of the Surface Stereo Imager when the pile was covered in freshly excavated material from the trench. The spectral observation did not produce any sign of water-ice, just typical soil for the site. However, the bigger clumps do show a platy texture that could be consistent with elevated concentration of salts in the soil from deep in Stone Soup. The team chose that location as the source for a soil sample to be analyzed in the lander's wet chemistry laboratory, which can identify soluble salts in the soil. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory

  10. Elementary calculation of the shutdown delay of a pile

    International Nuclear Information System (INIS)

    Yvon, J.

    1949-04-01

    This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)

  11. Theoretical computation background for transformation of foundations using pile drains

    Directory of Open Access Journals (Sweden)

    Ter-Martirosyan Zaven

    2017-01-01

    Full Text Available In the design of foundations for buildings and structures of various purposes, including improved risk, weak water-saturated clay soils with low mechanical characteristics are often found on a construction site. One of the possible ways of using them as a foundation is to seal them in various ways, including using pile drains of sand or rock stone material that are capable of both absorbing the load at the base and accelerating the process of filtration consolidation. This paper describes an analytical solution to the problem of interaction between the pile and the mattress with the surrounding soil of the foundation, taking into account the possibility of expanding the pile shaft. Solutions are obtained for determining the stresses in the shaft of the pile drain and in the soil under the mattress. The solution takes into account the influence of the pre-stressed state of the foundation after compaction on the formation of a stress-strain state during the erection and operation of structures. The solutions are relevant for consolidating pile drains made of rubble or for jet grouting piles, the rigidity of which is comparable to the rigidity of the surrounding soil. The paper describes the technique for determining the characteristics of the strength and deformability of the converted foundation and the results of large-scale tests at the experimental site for the construction of a large energy facility in Russia.

  12. Retrofitting Of RCC Piles By Using Basalt Fiber Reinforced Polymer BFRP Composite Part 1 Review Papers On RCC Structures And Piles Retrofitting Works.

    Directory of Open Access Journals (Sweden)

    R. Ananda Kumar

    2015-01-01

    Full Text Available Abstract Retrofitting works are immensely essential for deteriorated and damaged structures in Engineering and Medical fields in order to keep or return to the originality for safe guarding the structures and consumers. In this paper different types of methods of retrofitting review notes are given based on the experimental numerical and analytical methods results on strengthening the Reinforced cement concrete RCC structures including RCC piles. Soil-pile interaction on axial load lateral load reviews are also presented. This review paper is prepared to find out the performance of basalt fibre reinforced polymer BFRP composite retrofitted reinforced cement concrete single end bearing piles.

  13. Bore pile foundation tall buildings closed in the heritage building

    Science.gov (United States)

    Triastuti, Nusa Setiani

    2017-11-01

    Bore pile foundation for high building surroundings heritage building should be not damage. Construction proses must good, no necking, no mixed deep water, no sliding soil, nonporous concrete. Objective the execution of bore pile so that heritage buildings and neighboring buildings that are old do not experience cracks, damage and tilting. The survey methodology was observe the process of the implementation of the dominant silt, clay soil, in addition a limited space and to analyze the results of loading tests, investigations of soil and daily reports. Construction process determines the success of the structure bore pile in high building structure bearing, without damaging a heritage building. Attainment the hard soil depth, density concrete, observable clean reinforcement in the implementation. Monitoring the implementation of, among others, the face of the ground water little reduce in the area and outside the footprint of the building, no impact of vibration drilling equipment, watching the mud content on the water coming out at the time of drilling, concrete volume was monitored each 2 m bore depth of pile, The result researched heritage building was not damage. The test results bore pile axial, lateral analyzed the results have the appropriate force design required.

  14. Thermal response test data of five quadratic cross section precast pile heat exchangers

    Directory of Open Access Journals (Sweden)

    Maria Alberdi-Pagola

    2018-06-01

    Full Text Available This data article comprises records from five Thermal Response Tests (TRT of quadratic cross section pile heat exchangers. Pile heat exchangers, typically referred to as energy piles, consist of traditional foundation piles with embedded heat exchanger pipes. The data presented in this article are related to the research article entitled “Comparing heat flow models for interpretation of precast quadratic pile heat exchanger thermal response tests” (Alberdi-Pagola et al., 2018 [1]. The TRT data consists of measured inlet and outlet temperatures, fluid flow and injected heat rate recorded every 10 min. The field dataset is made available to enable model verification studies.

  15. Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality

    Science.gov (United States)

    The EPA report, Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality, summarizes the research findings on the best practices for building roadside vegetative barriers to improve air quality. This fact sheet describ

  16. 20051655 - Petronas, Capacity of Driven Piles Offshore Malaysia

    DEFF Research Database (Denmark)

    Augustesen, Anders; Andersen, Lars

    This document is the third of four notes concerning the vertical capacity of piles. It includes an assessment of the effect of previous static load testing upon the measured capacity, i.e. preshearing effects.......This document is the third of four notes concerning the vertical capacity of piles. It includes an assessment of the effect of previous static load testing upon the measured capacity, i.e. preshearing effects....

  17. 3D Numerical Modeling of Pile Group Responses to Excavation-Induced Stress Release in Silty Clay

    Directory of Open Access Journals (Sweden)

    M. A. Soomro

    2018-02-01

    Full Text Available Development of underground transportation systems consists of tunnels, basement construction excavations and cut and cover tunnels which may encounter existing pile groups during their construction. Since many previous studies mainly focus on the effects of excavations on single piles, settlement and load transfer mechanism of a pile group subjected to excavation-induced stress release are not well investigated and understood. To address these two issues, three-dimensional coupled-consolidation numerical analysis is conducted by using a hypoplastic model which takes small-strain stiffness into account. A non-linear pile group settlement was induced. This may be attributed to reduction of shaft resistance due to excavation induced stress release, the pile had to settle substantially to further mobilise end-bearing. Compared to the Sp of the pile group, induced settlement of the single pile is larger with similar settlement characteristics. Due to the additional settlement of the pile group, factor of safety for the pile group can be regarded as decreasing from 3.0 to 1.4, based on a displacement-based failure load criterion. Owing to non-uniform stress release, pile group tilted towards the excavation with value of 0.14%. Due to excavation-induced stress release and dragload, head load of rear piles was reduced and transferred to rear piles. This load transfer can increase the axial force in front piles by 94%.

  18. Bearing capacity of helical pile foundation in peat soil from different, diameter and spacing of helical plates

    Science.gov (United States)

    Fatnanta, F.; Satibi, S.; Muhardi

    2018-03-01

    In an area dominated by thick peat soil layers, driven piles foundation is often used. These piles are generally skin friction piles where the pile tips do not reach hard stratum. Since the bearing capacity of the piles rely on the resistance of their smooth skin, the bearing capacity of the piles are generally low. One way to increase the bearing capacity of the piles is by installing helical plates around the pile tips. Many research has been performed on helical pile foundation. However, literature on the use of helical pile foundation on peat soil is still hardly found. This research focus on the study of axial bearing capacity of helical pile foundation in peat soil, especially in Riau Province. These full-scale tests on helical pile foundation were performed in a rectangular box partially embedded into the ground. The box is filled with peat soil, which was taken from Rimbo Panjang area in the district of Kampar, Riau Province. Several helical piles with different number, diameter and spacing of the helical plates have been tested and analysed. The tests result show that helical pile with three helical plates of uniform diameter has better bearing capacity compared to other helical piles with varying diameter and different number of helical plates. The bearing capacity of helical pile foundation is affected by the spacing between helical plates. It is found that the effective helical plates spacing for helical pile foundation with diameter of 15cm to 35cm is between 20cm to 30cm. This behaviour may be considered to apply to other type of helical pile foundations in peat soil.

  19. Deformation Measurement of a Driven Pile Using Distributed Fibre-optic Sensing

    Science.gov (United States)

    Monsberger, Christoph; Woschitz, Helmut; Hayden, Martin

    2016-03-01

    New developments in distributed fibre-optic sensing allow the measurement of strain with a very high precision of about 1 µm / m and a spatial resolution of 10 millimetres or even better. Thus, novel applications in several scientific fields may be realised, e. g. in structural monitoring or soil and rock mechanics. Especially due to the embedding capability of fibre-optic sensors, fibre-optic systems provide a valuable extension to classical geodetic measurement methods, which are limited to the surface in most cases. In this paper, we report about the application of an optical backscatter reflectometer for deformation measurements along a driven pile. In general, pile systems are used in civil engineering as an efficient and economic foundation of buildings and other structures. Especially the length of the piles is crucial for the final loading capacity. For optimization purposes, the interaction between the driven pile and the subsurface material is investigated using pile testing methods. In a field trial, we used a distributed fibre-optic sensing system for measuring the strain below the surface of an excavation pit in order to derive completely new information. Prior to the field trial, the fibre-optic sensor was investigated in the laboratory. In addition to the results of these lab studies, we briefly describe the critical process of field installation and show the most significant results from the field trial, where the pile was artificially loaded up to 800 kN. As far as we know, this is the first time that the strain is monitored along a driven pile with such a high spatial resolution.

  20. 40 CFR 411.30 - Applicability; description of the materials storage piles runoff subcategory.

    Science.gov (United States)

    2010-07-01

    ... materials storage piles runoff subcategory. 411.30 Section 411.30 Protection of Environment ENVIRONMENTAL... Materials Storage Piles Runoff Subcategory § 411.30 Applicability; description of the materials storage piles runoff subcategory. The provisions of this subpart are applicable to discharges resulting from the...

  1. The role of the waveform in pulse pile-up

    International Nuclear Information System (INIS)

    Datlowe, D.W.

    1977-01-01

    Pulse pile-up is the distortion of pulse-height distributions due to the overlap of detector responses to the arrival of two or more particles or photons within the detector resolving time. This paper presents a computational technique for simulating pile-up effects, which includes explicitly the dependence on the pulse-shape of the detector system. The basis of the technique is the manipulation of probability densities. The method is applicable to all types of linear pulse counting systems for nucleons, electrons, and photons, as long as the result is a pulse-height distribution. The algorithms are highly efficient in the amount of computing required for simulations, and internal checks for the numerical accuracy of the results are included. Studies of pile-up by monoenergetic pulses are used to determine the interrelationship between pulse shapes and spectral features; this information can be used to minimize pile-up. For broad spectra, the square wave approximation is compared with the present model including the correct waveform; introducing the pulse shape information smooths spectral features but does not qualitatively change the spectrum. (Auth.)

  2. Observation of Spectral Signatures of 1/f Dynamics in Avalanches on Granular Piles

    Science.gov (United States)

    Kim, Yong W.; Nishino, Thomas K.

    1997-03-01

    Granular piles of monodisperse glass spheres, 0.46+0.03 mm in diameter, have been studied. The base diameter of the pile has been varied from 3/8" to 2" in 1/8" increments. A single-grain dispenser with greater than 95consisting of a stepping motor-actuated reciprocating arm with a single-grain scoop. Each grain is dropped on the apex of the pile with lowest possible landing velocity at intervals at least 30longer than the duration of largest avalanches for each given pile. Each grain being added and being lost in avalanches from the pile is optically detected and recorded. The power spectrum of the net addition of grains to the pile as a function of time is found to be robustly 1/f for all base sizes. A wide variety of dynamical properties of 1/f systems, as obtained from the high precision data, will be presented.

  3. Numerical Simulation by using Soldiers Pile of the Embankment on Semarang-Solo Highway

    Science.gov (United States)

    Tumanduk, M. S. S. S.; Maki, T. S.; Pangkey, T. U. Y.; Pandeiroth, Y. C.

    2018-02-01

    Semarang-Solo highway works section II Gedawang-Penggaron constitutes a labile area. It is thought to be effect of the existence of coat clay shale which have moulded. For the purpose of anticipating the embankment mass movement it is placed line bored pile and stringed up (soldiers pile). The objective of this research is to know the efficient use of soldier’s pile of the embankment on Semarang-Solo highway section II Gedawang-Penggaron pursuant based upon numerical simulation. The result of analysis depicts that original slope in a stabil state with horizontal displacement which equal to 0.06 m and safety factor (SF) which equal to 1.31. The strengthened embankment with bored pile is not effective to give am SF improvement at slope so that, at this phase, the slope cannot be slid to be safe enough from landslide namely with horizontal displacement which equal to 0.20 m and SF which equal to 1.09. The effect of traffic load horizontal displacement is which equal to 0.21 m with SF which equal to 1.00. The earthquake simulation results horizontal displacement which equal to 0.75 m with SF which equal to 1.00. Long variation of bored pile of phase II by neglecting bored pile phase III at the depth 35 m yields horizontal displacement which equal to 0.03 m and SF optimum which equal to 2.17. The variation of pile location by placing bored pile under embankment slope foot with distance from the location of bored pile of phase II which equal to 20 m without changing the profile of the existing bored pile creates the horizontal displacement which equals to 0.02 m with SF which equal to 2.29. The result of the horizontal displacement and SF of the two alternative is safer compared to the existing condition (SF>1.5).

  4. Small-Scale Quasi-Static Tests on Non-Slender Piles Situated in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    In the period from February 2009 till March 2011 a series of small-scale tests on pile foundations has been conducted at Aalborg University. In all the tests the piles have been exposed to quasi-static loading and all the tests have been conducted in a pressure tank. The objective of the tests has...... been to investigate the effect of pile diameter and length to diameter ratio on the soil response in sand for non-slender piles. Further, the tests have been conducted to calibrate a three-dimensional numerical model in the commercial program FLAC3D....

  5. Design of Jetty Piles Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Yongjei Lee

    2014-01-01

    Full Text Available To overcome the complication of jetty pile design process, artificial neural networks (ANN are adopted. To generate the training samples for training ANN, finite element (FE analysis was performed 50 times for 50 different design cases. The trained ANN was verified with another FE analysis case and then used as a structural analyzer. The multilayer neural network (MBPNN with two hidden layers was used for ANN. The framework of MBPNN was defined as the input with the lateral forces on the jetty structure and the type of piles and the output with the stress ratio of the piles. The results from the MBPNN agree well with those from FE analysis. Particularly for more complex modes with hundreds of different design cases, the MBPNN would possibly substitute parametric studies with FE analysis saving design time and cost.

  6. Centrifuge modelling of drained lateral pile - soil response

    DEFF Research Database (Denmark)

    Klinkvort, Rasmus Tofte

    of rigid piles. The tests have been performed in homogeneously dense dry or saturated Fontainebleau sand in order to mimic simplified drained offshore soil conditions. Approximately half of the tests have been carried out to investigate the centrifuge procedure in order to create a methodology of testing...... tests were used to investigate the pile - soil interaction to gain a better in-sight into the complex problem. A monotonic test series was carried out initially and then pile - soil interaction curves were deduced from these tests and compared with methodologies used today. The results indicate...... that the current methodologies can be improved and a modification to the methodology has been proposed. Secondly, a cyclic test series was carried out. The accumulation of displacement and the change in secant stiffness of the total response of these tests were evaluated. A simple mathematical model was proposed...

  7. Effect of piles on the seismic response of mosques minarets

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed Abdel-Motaal

    2014-03-01

    Minaret (60.0-m height was studied to investigate the effects of soil stiffness, pile length, diameter, and arrangement, on the minaret and pile dynamic behavior. Comparison between study results and conventional analysis method is illustrated. Study results, discussion, and conclusion are given.

  8. Numerical Modelling of Large-Diameter Steel Piles at Horns Rev

    DEFF Research Database (Denmark)

    Augustesen, Anders Hust; Brødbæk, K. T.; Møller, M.

    2009-01-01

    Today large-diameter monopiles are the most common foundation type used for large offshore wind farms. This paper aims to investigate the behaviour of monopiles under monotonic loading taking the interaction between the pile and the subsoil into account. Focus is paid to a monopile used as founda......Today large-diameter monopiles are the most common foundation type used for large offshore wind farms. This paper aims to investigate the behaviour of monopiles under monotonic loading taking the interaction between the pile and the subsoil into account. Focus is paid to a monopile used...... as foundation for a wind turbine at Horns Rev located in the Danish sector of the North Sea. The outer diameter of the pile is 4 m and the subsoil at the location consists primarily of sand. The behaviour of the pile is investigated under realistic loading conditions by means of a traditional Winkler...

  9. Static Load Test on Instrumented Pile – Field Data and Numerical Simulations

    Directory of Open Access Journals (Sweden)

    Krasiński Adam

    2017-09-01

    Full Text Available Static load tests on foundation piles are generally carried out in order to determine load – the displacement characteristic of the pile head. For standard (basic engineering practices this type of test usually provides enough information. However, the knowledge of force distribution along the pile core and its division into the friction along the shaft and the resistance under the base can be very useful. Such information can be obtained by strain gage pile instrumentation [1]. Significant investigations have been completed on this technology, proving its utility and correctness [8], [10], [12]. The results of static tests on instrumented piles are not easy to interpret. There are many factors and processes affecting the final outcome. In order to understand better the whole testing process and soil-structure behavior some investigations and numerical analyses were done. In the paper, real data from a field load test on instrumented piles is discussed and compared with numerical simulation of such a test in similar conditions. Differences and difficulties in the results interpretation with their possible reasons are discussed. Moreover, the authors used their own analytical solution for more reliable determination of force distribution along the pile. The work was presented at the XVII French-Polish Colloquium of Soil and Rock Mechanics, Łódź, 28–30 November 2016.

  10. Graphite reactor physics; Physique des piles a graphite

    Energy Technology Data Exchange (ETDEWEB)

    Bacher, P; Cogne, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Noc, B [Electricite de France (EDF), 75 - Paris (France)

    1964-07-01

    The study of graphite-natural uranium power reactor physics, undertaken ten years ago when the Marcoule piles were built, has continued to keep in step with the development of this type of pile. From 1960 onwards the critical facility Marius has been available for a systematic study of the properties of lattices as a function of their pitch, of fuel geometry and of the diameter of cooling channels. This study has covered a very wide field: lattice pitch varying from 19 to 38 cm. uranium rods and tubes of cross-sections from 6 to 35 cm{sup 2}, channels with diameters between 70 and 140 mm. The lattice calculation methods could thus be checked and where necessary adapted. The running of the Marcoule piles and the experiments carried out on them during the last few years have supplied valuable information on the overall evolution of the neutronic properties of the fuel as a function of irradiation. More detailed experiments have also been performed in Marius with plutonium-containing fuels (irradiated or synthetic fuels), and will be undertaken at the beginning of 1965 at high temperature in the critical facility Cesar, which is just being completed at Cadarache. Spent fuel analyses complement these results and help in their interpretation. The thermalization and spectra theories developed in France can thus be verified over the whole valid temperature range. The efficiency of control rods as a function of their dimensions, the materials of which they are made and the lattices surrounding them has been measured in Marius, and the results compared with calculation on the one hand and with the measurements carried out in EDF 1 on the other. Studies on the control proper of graphite piles were concerned essentially with the risks of spatial instability and the means of detecting and controlling them, and with flux distortions caused by the control rods. (authors) [French] Entreprise il y a dix ans a l'occasion de la construction des piles de Marcoule, l'etude de la

  11. Design and Preparation of Carbon Based Composite Phase Change Material for Energy Piles.

    Science.gov (United States)

    Yang, Haibin; Memon, Shazim Ali; Bao, Xiaohua; Cui, Hongzhi; Li, Dongxu

    2017-04-07

    Energy piles-A fairly new renewable energy concept-Use a ground heat exchanger (GHE) in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs) to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs (expanded graphite-based PCM and graphite nanoplatelet-based PCM) were prepared by vacuum impregnation for potential application in energy piles. Thereafter, a systematic study was performed and different characterization tests were carried out on two composite PCMs. The composite PCMs retained up to 93.1% of paraffin and were chemically compatible, thermally stable and reliable. The latent heat of the composite PCM was up to 152.8 J/g while the compressive strength of cement paste containing 10 wt % GNP-PCM was found to be 37 MPa. Hence, the developed composite PCM has potential for thermal energy storage applications.

  12. Model tests and numerical analyses on horizontal impedance functions of inclined single piles embedded in cohesionless soil

    Science.gov (United States)

    Goit, Chandra Shekhar; Saitoh, Masato

    2013-03-01

    Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics. Two practical pile inclinations of 5° and 10° in addition to a vertical pile embedded in cohesionless soil and subjected to lateral harmonic pile head loadings for a wide range of frequencies are considered. Results obtained with low-to-high amplitude of lateral loadings on model soil-pile systems encased in a laminar shear box show that the local nonlinearities have a profound impact on the horizontal impedance functions of piles. Horizontal impedance functions of inclined piles are found to be smaller than the vertical pile and the values decrease as the angle of pile inclination increases. Distinct values of horizontal impedance functions are obtained for the `positive' and `negative' cycles of harmonic loadings, leading to asymmetric force-displacement relationships for the inclined piles. Validation of these experimental results is carried out through three-dimensional nonlinear finite element analyses, and the results from the numerical models are in good agreement with the experimental data. Sensitivity analyses conducted on the numerical models suggest that the consideration of local nonlinearity at the vicinity of the soil-pile interface influence the response of the soil-pile systems.

  13. Stability Limits for Rubble Pile Asteroid Shapes

    Science.gov (United States)

    Scheeres, Daniel

    2018-04-01

    The stability of rubble pile asteroids are explored analytically, using simple models for their constituent components. Specifically, we look at the stability of spherical components resting and potentially rolling on each other as a function of their relative sizes, configuration and number. This talk will present some recent results in this problem. Of specific interest is a 5:1 limit on the elongation of a rubble pile body for stability, which is interestingly the same extreme elongation found for the first interstellar object. This limit is for a rubble pile consisting of stacked spheres, resting on each other in a straight line. If there are 5 or less bodies resting on each other in this configuration, there is an interval of spin rates for which the configuration is stable. If there are 6 or more bodies stacked as such, the spin rate for it to stabilize is beyond the spin rate at which it fissions. The talk will also explore additional results for different configurations of bodies resting on each other.

  14. Response of stiff piles in sand to long-term cyclic lateral loading

    DEFF Research Database (Denmark)

    Bakmar, Christian LeBlanc; Houlsby, Guy T.; Byrne, Byron W.

    2010-01-01

    . To address this, a series of laboratory tests were conducted where a stiff pile in drained sand was subjected to between 8000 and 60000 cycles of combined moment and horizontal loading. A typical design for an offshore wind turbine monopile was used as a basis for the study, to ensure that pile dimensions...... and loading ranges were realistic. A complete non-dimensional framework for stiff piles in sand is presented and applied to interpret the test results. The accumulated rotation was found to be dependent on relative density and was strongly affected by the characteristics of the applied cyclic load. The pile...... stiffness increased with number of cycles, which contrasts with the current methodology where static p - y curves are degraded to account for cyclic loading. Methods are presented to predict the change in stiffness and the accumulated rotation of a stiff pile due to long-term cyclic loading. The use...

  15. Comparative Model Tests of SDP and CFA Pile Groups in Non-Cohesive Soil

    Science.gov (United States)

    Krasiński, Adam; Kusio, Tomasz

    2015-02-01

    The research topic relates to the subject of deep foundations supported on continuous flight auger (CFA) piles and screw displacement piles (SDP). The authors have decided to conduct model tests of foundations supported on the group of piles mentioned above and also the tests of the same piles working as a single. The tests are ongoing in Geotechnical Laboratory of Gdaňsk University of Technology. The description of test procedure, interpretation and analysis of the preliminary testing series results are presented in the paper.

  16. Feasibility of the Half Pile Supporting of Hand-dug Piles%人工挖孔桩半桩支护方案可行性分析

    Institute of Scientific and Technical Information of China (English)

    张赛威

    2015-01-01

    Taking the actual deep excavation project for the study object, this paper carried out the pile numerical computation and numerical simulation. By comparing the results, the half pile for hand-dug piles is feasible.%本文以实际工程深基坑工程为研究对象,分别对桩基进行数值计算和数值模拟,通过对结果进行对比可以看出,人工挖孔桩采用半桩基是可行的。

  17. Piling up technology of goods irradiated by single plate source

    International Nuclear Information System (INIS)

    Xia Hezhou; Chen Yuxia; Cao Hongyun; Lin Yong; Zhou guoquan

    1999-01-01

    In the irradiation process of piling up goods in static state, four irradiation working sites and single plate source was adopted. The results showed that piling up in this way remarkably raised the irradiation quality of goods. The utilization rate of radioactive ray reached 22.27%

  18. Out-of-pile test of the crud separator system. (I)

    International Nuclear Information System (INIS)

    Takasaki, Akito; Iimura, Katsumichi; Tanaka, Isao

    1991-01-01

    The JMTR Project has been developing the crud separator system since 1981, and the advanced system has been fabricated for the in-pile test to be performed in the HBWR (Norway). The crud separator system removes magnetized crud circulating in a primary circuit by the permanent magnet assembly surrounded inside and outside of the separator vessel. Before the in-pile test, out-of-pile test was carried out in the JMTR Project under the condition of atmospheric pressure and room temperature, and the simplified theoretical analysis for crud separation mechanism was also carried out. The out-of-pile test results suggested that separation factor increased with increasing magnetic susceptibility of crud and crud particle diameter, and decreased with increasing flow rate. These results were in good agreement with the theoretical analysis. The test results also showed that the crud size enlarger was effective in lower separation factor region, which related to lower magnetic susceptibility of crud, smaller crud diameter and higher flow rate. (author)

  19. Torsional vibration of a pipe pile in transversely isotropic saturated soil

    Science.gov (United States)

    Zheng, Changjie; Hua, Jianmin; Ding, Xuanming

    2016-09-01

    This study considers the torsional vibration of a pipe pile in a transversely isotropic saturated soil layer. Based on Biot's poroelastic theory and the constitutive relations of the transversely isotropic medium, the dynamic governing equations of the outer and inner transversely isotropic saturated soil layers are derived. The Laplace transform is used to solve the governing equations of the outer and inner soil layers. The dynamic torsional response of the pipe pile in the frequency domain is derived utilizing 1D elastic theory and the continuous conditions at the interfaces between the pipe pile and the soils. The time domain solution is obtained by Fourier inverse transform. A parametric study is conducted to demonstrate the influence of the anisotropies of the outer and inner soil on the torsional dynamic response of the pipe pile.

  20. Case Study of CPT-based Design Methods for Axial Capacity of Driven Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

    2012-01-01

    loaded offshore driven piles in cohesionless soil has until now been the β-method given in API. The API-method is based on the effective overburden pressure at the depth in question. Previous studies show deviations between full-scale load test measurements of the axial pile capacity and the predictions...... found by means of the API-method. Compared to the test measurements, the API-method under-estimates the capacity of short piles (piles in loose sand, and gives a shaft capacity less conservative for piles in tension than for piles in compression......Today the design of onshore axially loaded driven piles in cohesionless soil is commonly made on basis of CPT-based methods because field investigations have shown strong correlation between the local shaft friction and the CPT cone resistance. However, the recommended design method for axially...

  1. INFLUENCE OF A ROUND CAP ON THE BEARING CAPACITY OF A LATERALLY LOADED PILE

    Directory of Open Access Journals (Sweden)

    Buslov Anatoliy Semenovich

    2012-07-01

    The data has proven that cap-covered piles are substantially more economical (over 40 % in terms of materials consumption rate if compared to constant cross-section piles (cap-free or broadening piles, all other factors being equal.

  2. Comparative Model Tests of SDP and CFA Pile Groups in Non-Cohesive Soil

    Directory of Open Access Journals (Sweden)

    Krasiński Adam

    2015-02-01

    Full Text Available The research topic relates to the subject of deep foundations supported on continuous flight auger (CFA piles and screw displacement piles (SDP. The authors have decided to conduct model tests of foundations supported on the group of piles mentioned above and also the tests of the same piles working as a single. The tests are ongoing in Geotechnical Laboratory of Gdaňsk University of Technology. The description of test procedure, interpretation and analysis of the preliminary testing series results are presented in the paper.

  3. Radioactive safety analysis and assessment of waste rock pile site in uranium tailings

    International Nuclear Information System (INIS)

    Liu Changrong; Liu Zehua; Wang Zhiyong; Zhou Xinghuo

    2007-01-01

    Based on theoretical calculation and in-situ test results, distribution and emissions of radioactive nuclides of uranium tailings impoundment and waste rock pile sites are analyzed in this paper. It is pointed out that 222 Rn is the main nuclide of uranium tailings impoundment and waste rock pile site. Also 222 Rn is the main source term of public dose. 222 Rn concentrations in the atmospheric environment around and individual dose to Rn gradually decrease with increasing distances to uranium tailings impoundment and waste rock pile site. Based on in-situ tests on five uranium tailings impoundment and waste rock pile sites, a decisive method and safety protection distance are presented, which can be used to guide the validation and design of radioactive safety protection in uranium tailings impoundment and waste rock pile sites. (authors)

  4. Three-dimensional finite element nonlinear dynamic analysis of pile groups for lateral transient and seismic excitations

    International Nuclear Information System (INIS)

    Maheshwari, B.K.; Truman, K.Z.; El Naggar, M.H.; Gould, P.L.

    2004-01-01

    The effects of material nonlinearity of soil and separation at the soil-pile interface on the dynamic behaviour of a single pile and pile groups are investigated. An advanced plasticity-based soil model, hierarchical single surface (HiSS), is incorporated in the finite element formulation. To simulate radiation effects, proper boundary conditions are used. The model and algorithm are verified with analytical results that are available for elastic and elastoplastic soil models. Analyses are performed for seismic excitation and for the load applied on the pile cap. For seismic analysis, both harmonic and transient excitations are considered. For loading on the pile cap, dynamic stiffness of the soil-pile system is derived and the effect of nonlinearity is investigated. The effects of spacing between piles are investigated, and it was found that the effect of soil nonlinearity on the seismic response is very much dependent on the frequency of excitation. For the loading on a pile cap, the nonlinearity increases the response for most of the frequencies of excitation while decreasing the dynamic stiffness of the soil-pile system. (author)

  5. Towards building a neural network model for predicting pile static load test curves

    Directory of Open Access Journals (Sweden)

    Alzo’ubi A. K.

    2018-01-01

    Full Text Available In the United Arab Emirates, Continuous Flight Auger piles are the most widely used type of deep foundation. To test the pile behaviour, the Static Load Test is routinely conducted in the field by increasing the dead load while monitoring the displacement. Although the test is reliable, it is expensive to conduct. This test is usually conducted in the UAE to verify the pile capacity and displacement as the load increase and decreases in two cycles. In this paper we will utilize the Artificial Neural Network approach to build a model that can predict a complete Static Load Pile test. We will show that by integrating the pile configuration, soil properties, and ground water table in one artificial neural network model, the Static Load Test can be predicted with confidence. We believe that based on this approach, the model is able to predict the entire pile load test from start to end. The suggested approach is an excellent tool to reduce the cost associated with such expensive tests or to predict pile’s performance ahead of the actual test.

  6. Contribution to Estimating Bearing Capacity of Pile in Clayey Soils

    Science.gov (United States)

    Drusa, Marián; Gago, Filip; Vlček, Jozef

    2016-12-01

    The estimation of real geotechnical parameters is key factor for safe and economic design of geotechnical structures. One of these are pile foundations, which require proper design and evaluation due to accessing more deep foundation soil and because remediation work of not bearable piles or broken piles is a crucial operation. For this reason, geotechnical field testing like cone penetration test (CPT), standard penetration (SPT) or dynamic penetration test (DP) are realized in order to receive continuous information about soil strata. Comparing with rotary core drilling type of survey with sampling, these methods are more progressive. From engineering geologist point of view, it is more important to know geological characterization of locality but geotechnical engineers have more interest above the real geotechnical parameters of foundation soils. The role of engineering geologist cannot be underestimated because important geological processes in origin or during history can explain behaviour of a geological environment. In effort to streamline the survey, investigation by penetration tests is done as it is able to provide enough information for designers. This paper deals with actual trends in pile foundation design; because there are no new standards and usable standards are very old. Estimation of the bearing capacity of a single pile can be demonstrated on the example of determination of the cone factor Nk from CPT testing. Then results were compared with other common methods.

  7. Contribution to Estimating Bearing Capacity of Pile in Clayey Soils

    Directory of Open Access Journals (Sweden)

    Drusa Marián

    2016-12-01

    Full Text Available The estimation of real geotechnical parameters is key factor for safe and economic design of geotechnical structures. One of these are pile foundations, which require proper design and evaluation due to accessing more deep foundation soil and because remediation work of not bearable piles or broken piles is a crucial operation. For this reason, geotechnical field testing like cone penetration test (CPT, standard penetration (SPT or dynamic penetration test (DP are realized in order to receive continuous information about soil strata. Comparing with rotary core drilling type of survey with sampling, these methods are more progressive. From engineering geologist point of view, it is more important to know geological characterization of locality but geotechnical engineers have more interest above the real geotechnical parameters of foundation soils. The role of engineering geologist cannot be underestimated because important geological processes in origin or during history can explain behaviour of a geological environment. In effort to streamline the survey, investigation by penetration tests is done as it is able to provide enough information for designers. This paper deals with actual trends in pile foundation design; because there are no new standards and usable standards are very old. Estimation of the bearing capacity of a single pile can be demonstrated on the example of determination of the cone factor Nk from CPT testing. Then results were compared with other common methods.

  8. Mn2C sheet as an electrode material for lithium-ion battery: A first-principles prediction

    International Nuclear Information System (INIS)

    Zhou, Yungang; Zu, Xiaotao

    2017-01-01

    Graphical abstract: Combined with strong Li bond, low Li diffusion barrier, superior electrical conductivity and high theoretical capacity, Mn 2 C Sheet is found to be a new promising electrode material for Lithium-Ion Battery. - Highlights: • Li atom bind strongly with Mn 2 C sheet with a very low adsorption energy. • Pristine Mn 2 C sheet exhibits metallic character. • Li atom can easily and freely migrate on the Mn 2 C sheet. • Lithiation to a high content is feasible. • Theoretical capacity of Mn 2 C sheet arrives at 879 mAhg −1 . - Abstract: A search for high-efficiency electrode materials is crucial for the application of Li-ion batteries (LIBs). Using density functional theory (DFT), we assess the Mn 2 C sheet, a new MXene, as a suitable electrode material. Our studies show that Li atoms can bind strongly to the Mn 2 C sheet, with low adsorption energy of −1.93 eV. A pristine Mn 2 C sheet exhibits metallic characteristic, offering an intrinsic advantage for the transportation of electrons in material. A very low energy barrier of 0.05 eV is predicted, showing that Li ion can easily and freely migrate on the Mn 2 C sheet. In addition, with the increase of Li content, adsorption energy varies minimally within a range of energy that spans only 0.27 eV, showing that lithiation to a high content is feasible. Furthermore, we found that, because of the bilayer adsorptions on both sides of the Mn 2 C sheet, the theoretical capacity of the Mn 2 C sheet is 879 mAhg −1 , which is greater than that of most two-dimentional (2D) electrode materials. All these results reveal a new promising MXene material for LIBs. We also studied the effects of oxidation and fluorination on the electrochemical properties of the Mn 2 C sheet and found that oxidation and fluorination will fade the electrochemical properties of the Mn 2 C sheet in general.

  9. Instability risk assessment of construction waste pile slope based on fuzzy entropy

    Science.gov (United States)

    Ma, Yong; Xing, Huige; Yang, Mao; Nie, Tingting

    2018-05-01

    Considering the nature and characteristics of construction waste piles, this paper analyzed the factors affecting the stability of the slope of construction waste piles, and established the system of the assessment indexes for the slope failure risks of construction waste piles. Based on the basic principles and methods of fuzzy mathematics, the factor set and the remark set were established. The membership grade of continuous factor indexes is determined using the "ridge row distribution" function, while that for the discrete factor indexes was determined by the Delphi Method. For the weight of factors, the subjective weight was determined by the Analytic Hierarchy Process (AHP) and objective weight by the entropy weight method. And the distance function was introduced to determine the combination coefficient. This paper established a fuzzy comprehensive assessment model of slope failure risks of construction waste piles, and assessed pile slopes in the two dimensions of hazard and vulnerability. The root mean square of the hazard assessment result and vulnerability assessment result was the final assessment result. The paper then used a certain construction waste pile slope as the example for analysis, assessed the risks of the four stages of a landfill, verified the assessment model and analyzed the slope's failure risks and preventive measures against a slide.

  10. 水下挖孔灌注桩施工技术在复合地层中的应用%Application of Construction Techniques of Underwater Dug Piles to Construction of Underwater Dug Piles in Compound Stratum

    Institute of Scientific and Technical Information of China (English)

    王南海; 王吉兵

    2012-01-01

    为确保复合地层条件下水下挖孔灌注桩施工顺利,以猫铺2号大桥为背景,采取集水坑截水、无渗透排水等措施进行桩基施工.在河道上、下游远离桩基15 m处分别开挖1个上口半径8 m的集水坑,自然放坡,深度开挖至砂卵石层底;在河道上、下游远离施工区域挖掘1条宽2m、深1.5m的倒梯形水渠并铺设塑料薄膜,进、出水口设置在集水坑影响范围外;在集水坑位置搭设支架,安装倒链拴大流量潜水泵,将集水坑内的水泵至水渠内;采用间隔交错跳挖施工顺序施工水下挖孔灌注桩.在河滩砂卵石地层相同施工条件下,挖孔桩成孔和冲击成孔的工期、造价与环保效益的对比结果表明:对于单排4根桩,挖孔灌注桩的工期、造价分别为52 d、103 832元,均小于冲击成孔的工期和造价且较为环保.%To ensure the smooth construction of the underwater dug piles under the conditions of compound stratum, the Maopu Bridge No. 2 was cited as an example, the piles of the bridge were constructed by the measures of collecting water by the catch pits and dewatering with no seeping. At the places of 15 m far from the piles upstream and downstream in the river channel, a catch pit with its upper radius being 8 m and with natural slope was respectively excavated to the sand and pebble layer and at the place far from the construction area, an inverted trapezoidal water channel, 2 m wide and 1. 5 m deep, was also excavated and was laid with the plastic sheets. The water inlet and outlet were set beyond the influential range of the catch pit and at the catch pit, the scaffolding was set up and the high flow chain submersible pumps were installed. The water in the catch pits was pumped out to the water channel and the underwater dug piles were constructed by the construction sequences of alternative andinterval excavation. The comparison of the construction time schedules, cost, and environment benefits of the

  11. Seismic soil-structure interaction of foundations with large piles

    International Nuclear Information System (INIS)

    Zeevaert, L.

    1996-01-01

    In seismic regions with soft soil deposits subjected to ground surface subsidence, there is the necessity to support the weight of constructions on large diameter piles or piers hearing on deep firm strata. To justify the action of these elements working under flexo compression and shear, it is necessary to perform calculations of soil pile interaction from a practical engineering point of view and estimate the order of magnitude of the forces and displacements to which these elements will be subjected during the seismic action assigned to the foundation. In this paper we defined a pier as a large diameter pile constructed on site. Furthermore, in the seismic analysis it is necessary to evaluate the seismic pore water pressure to learn on the effective seismic soil stresses close to the ground surface. (author)

  12. Comparison of Three Different Methods for Pile Integrity Testing on a Cylindrical Homogeneous Polyamide Specimen

    Science.gov (United States)

    Lugovtsova, Y. D.; Soldatov, A. I.

    2016-01-01

    Three different methods for pile integrity testing are proposed to compare on a cylindrical homogeneous polyamide specimen. The methods are low strain pile integrity testing, multichannel pile integrity testing and testing with a shaker system. Since the low strain pile integrity testing is well-established and standardized method, the results from it are used as a reference for other two methods.

  13. Study of the light emitted in the moderation of a heavy-water pile

    International Nuclear Information System (INIS)

    Breton, D.

    1958-06-01

    During the running of a reactor which uses water as a neutron moderator, a bluish light is seen to appear inside the liquid. A detailed study of this radiation, undertaken on the Fontenay-aux-Roses pile, has shown that the spectrum is identical with that which characterises the light produced by the Cerenkov effect. The light intensity as a function of the pile power grows exponentially as a function of time when the pile diverges, with a lifetime equal to that of the rise in power. An examination of the various particles present in the pile has led to the conclusion that only electrons with an energy greater than 260 keV con produce the Cerenkov light. The light source thus produced is about 2.10 6 photons/cm 2 of water, when the pile power equals 1 watt. (author) [fr

  14. Analysis Method for Laterally Loaded Pile Groups Using an Advanced Modeling of Reinforced Concrete Sections.

    Science.gov (United States)

    Stacul, Stefano; Squeglia, Nunziante

    2018-02-15

    A Boundary Element Method (BEM) approach was developed for the analysis of pile groups. The proposed method includes: the non-linear behavior of the soil by a hyperbolic modulus reduction curve; the non-linear response of reinforced concrete pile sections, also taking into account the influence of tension stiffening; the influence of suction by increasing the stiffness of shallow portions of soil and modeled using the Modified Kovacs model; pile group shadowing effect, modeled using an approach similar to that proposed in the Strain Wedge Model for pile groups analyses. The proposed BEM method saves computational effort compared to more sophisticated codes such as VERSAT-P3D, PLAXIS 3D and FLAC-3D, and provides reliable results using input data from a standard site investigation. The reliability of this method was verified by comparing results from data from full scale and centrifuge tests on single piles and pile groups. A comparison is presented between measured and computed data on a laterally loaded fixed-head pile group composed by reinforced concrete bored piles. The results of the proposed method are shown to be in good agreement with those obtained in situ.

  15. Analysis Method for Laterally Loaded Pile Groups Using an Advanced Modeling of Reinforced Concrete Sections

    Directory of Open Access Journals (Sweden)

    Stefano Stacul

    2018-02-01

    Full Text Available A Boundary Element Method (BEM approach was developed for the analysis of pile groups. The proposed method includes: the non-linear behavior of the soil by a hyperbolic modulus reduction curve; the non-linear response of reinforced concrete pile sections, also taking into account the influence of tension stiffening; the influence of suction by increasing the stiffness of shallow portions of soil and modeled using the Modified Kovacs model; pile group shadowing effect, modeled using an approach similar to that proposed in the Strain Wedge Model for pile groups analyses. The proposed BEM method saves computational effort compared to more sophisticated codes such as VERSAT-P3D, PLAXIS 3D and FLAC-3D, and provides reliable results using input data from a standard site investigation. The reliability of this method was verified by comparing results from data from full scale and centrifuge tests on single piles and pile groups. A comparison is presented between measured and computed data on a laterally loaded fixed-head pile group composed by reinforced concrete bored piles. The results of the proposed method are shown to be in good agreement with those obtained in situ.

  16. Progress In Developing An In-Pile Acoustically Telemetered Sensor Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James A.; Garrett, Steven L.; Heibel, Michael D.; Agarwal, Vivek; Heidrich, Brenden J.

    2016-09-01

    A salient grand challenge for a number of Department of Energy programs such as Fuels Cycle Research and Development ( includes Accident Tolerant Fuel research and the Transient Reactor Test Facility Restart experiments), Light Water Sustainability, and Advanced Reactor Technologies is to enhance our fundamental understanding of fuel and materials behavior under irradiation. Robust and accurate in-pile measurements will be instrumental to develop and validate a computationally predictive multi-scale understanding of nuclear fuel and materials. This sensing technology will enable the linking of fundamental micro-structural evolution mechanisms to the macroscopic degradation of fuels and materials. The in situ sensors and measurement systems will monitor local environmental parameters as well as characterize microstructure evolution during irradiation. One of the major road blocks in developing practical robust, and cost effective in-pile sensor systems, are instrument leads. If a wireless telemetry infrastructure can be developed for in-pile use, in-core measurements would become more attractive and effective. Thus to be successful in accomplishing effective in-pile sensing and microstructure characterization an interdisciplinary measurement infrastructure needs to be developed in parallel with key sensing technology. For the discussion in this research, infrastructure is defined as systems, technology, techniques, and algorithms that may be necessary in the delivery of beneficial and robust data from in-pile devices. The architecture of a system’s infrastructure determines how well it operates and how flexible it is to meet future requirements. The limiting path for the effective deployment of the salient sensing technology will not be the sensors themselves but the infrastructure that is necessary to communicate data from in-pile to the outside world in a non-intrusive and reliable manner. This article gives a high level overview of a promising telemetry

  17. Geomorphic reclmation of a coal refuse pile

    Science.gov (United States)

    Hopkinson, L. C.; Quaranta, J.

    2017-12-01

    Geomorphic reclamation is a technique that may offer opportunities to improve mine reclamation in Central Appalachia. The design approach is based on constructing a steady-state, mature landform condition and takes into account the long-term climatic conditions, soil types, terrain grade, and vegetation. Geomorphic reclamation has been applied successfully in semi-arid regions but has not yet been applied in Central Appalachia. This work describes a demonstration study where geomorphic landforming techniques are being applied to a coarse coal refuse pile in southern West Virginia, USA. The reclamation design includes four geomorphic watersheds that radially drain runoff from the pile. Each watershed has one central draining channel and incorporates compound slope profiles similarly to naturally eroded slopes. Planar slopes were also included to maintain the impacted area. The intent is to alter the hydrology to decrease water quality treatment costs. The excavation cut and fill volumes are comparable to those of more conventional refuse pile reclamation designs. If proven successful then this technique can be part of a cost-effective solution to improve water quality at active and future refuse facilities, abandoned mine lands, bond forfeiture sites, landfills, and major earthmoving activities within the region.

  18. Disaggregation of small, cohesive rubble pile asteroids due to YORP

    Science.gov (United States)

    Scheeres, D. J.

    2018-04-01

    The implication of small amounts of cohesion within relatively small rubble pile asteroids is investigated with regard to their evolution under the persistent presence of the YORP effect. We find that below a characteristic size, which is a function of cohesive strength, density and other properties, rubble pile asteroids can enter a "disaggregation phase" in which they are subject to repeated fissions after which the formation of a stabilizing binary system is not possible. Once this threshold is passed rubble pile asteroids may be disaggregated into their constituent components within a finite time span. These constituent components will have their own spin limits - albeit potentially at a much higher spin rate due to the greater strength of a monolithic body. The implications of this prediction are discussed and include modification of size distributions, prevalence of monolithic bodies among meteoroids and the lifetime of small rubble pile bodies in the solar system. The theory is then used to place constraints on the strength of binary asteroids characterized as a function of their type.

  19. The impact of wind energy turbine piles on ocean dynamics

    Science.gov (United States)

    Grashorn, Sebastian; Stanev, Emil V.

    2016-04-01

    The small- and meso-scale ocean response to wind parks has not been investigated in the southern North Sea until now with the help of high-resolution numerical modelling. Obstacles such as e.g. wind turbine piles may influence the ocean current system and produce turbulent kinetic energy which could affect sediment dynamics in the surrounding area. Two setups of the unstructured-grid model SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) have been developed for an idealized channel including a surface piercing cylindrical obstacle representing the pile and a more realistic test case including four exemplary piles. Experiments using a constant flow around the obstacles and a rotating M2 tidal wave are carried out. The resulting current and turbulence patterns are investigated to estimate the influence of the obstacles on the surrounding ocean dynamics. We demonstrate that using an unstructured ocean model provides the opportunity to embed a high-resolution representation of a wind park turbine pile system into a coarser North Sea setup, which is needed in order to perform a seamless investigation of the resulting geophysical processes.

  20. Study on the measures of tunnels side-crossing bridge based on sheltering effects of isolation piles

    Science.gov (United States)

    Tang, Jian; Liu, Jun yan; Liu, Yan

    2017-08-01

    Based on the transit line 3, we studied the effect of the bridge piles crossed closely from the side by the shield tunnel. Using the three-dimensional finite element numerical analysis software Midas GTS/NX, we analyzed the effect of shield tunnel on pile deformation, statistics are obtained that under the condition of pile, subgrade reinforcement and ground changes. The calculation results show that in the condition of reinforcement, the new tunnel shield crossing through the pile caused longitudinal disturbance of the tunnel surrounding strata along the tunnel, where the soil over the area is within a certain range of pile and settlement deformation of surface subsidence occurs, changing the surface roughly to the shape of “V”. The maximum value appears above the shield tunnel and the value is high. In combination with engineering geology, hydrogeology and environment factors, this paper adopted isolation pile reinforcement to the pile, and the simulated results show that, pile settlement was significantly reduced under the condition of pile reinforcement. The calculation results show the rationality of the reinforcement scheme to a certain extent, which provides a theoretical basis for the similar tunnel.

  1. Radiation Protection in the Experimental Pile Marius

    International Nuclear Information System (INIS)

    Cohendy, G.

    1962-01-01

    Measurements made around the experimental pile 'Marius' made it possible to determine the valid characteristics of the slabs designed to improve the biological protection by covering the charge and discharge pits. These measurements also made it possible to evaluate the risks occurring when the pile is operating at various Powers and to make a reasonable estimate of the value of the ratio of the total danger due to neutrons (thermal and fast) and γ radiation and to the danger due only to the γ radiation. A knowledge of this ratio makes it possible to make satisfactory evaluations with a single apparatus which is really portable. (author) [fr

  2. Investigation of pile foundations of nuclear power plants with help of non linear analyses

    International Nuclear Information System (INIS)

    Diaz, B.E.; Schulz, M.; Costa, E.; Vaz, L.E.

    1984-01-01

    A few important 1300 MW PWR nuclear power plants have been built over pile foundations. The design requirements of Nuclear Power Plants prescribe accurate investigation of the as built conditions of the foundation. This study must take into account the actual concrete strength existent among and along the pile shafts of the foundation. In order to simulate the structural response of the foundation up to the failure, a non linear analysis must be performed. In this paper the required computer analysis procedures will be described. It can be verified that the redistribution of the internal forces in this highly hyperstatic soil-structure system can be of two types. The total applied forces over the foundation are redistributed among the piles and for each pile itself a local redistribution of forces takes place along the pile shaft. This type of analysis allows an accurate investigation of the actual safety margin existent in the pile foundation, based on the actual as built conditions of the construction. (Author) [pt

  3. Design of anti-slide piles for slope stabilization in Wanzhou city, Three Gorges Area, China

    Science.gov (United States)

    Zhou, Chunmei; van Westen, Cees

    2013-04-01

    This study is related to the design of anti-slide piles for several landslides in Wanzhou city located in the Three Gorges area. Due to the construction of the Three Gorges Reservoir the hydro-geological conditions in this area have deteriorated significantly, leading to larger instability problems. China has invested a lot of money in slope stabilization measures for the treatment of landslides in the Three Gorges area. One of the methods for the stabilization of large landslides is the design of anti-sliding piles. This paper focuses on extensive slope stability analysis and modeling of the mechanical behavior of the landslide masses, and the parameters required for designing the number, size and dimensions of reinforced concrete stabilization piles. The study focuses on determining the rock parameters, anchor depth, and the pile and soil interaction coefficient. The study aims to provide guidelines for anti-slide pile stabilization works for landslides in the Wanzhou area. The research work contains a number of aspects. First a study is carried out on the distribution of pressures expected on the piles, using two different methods that take into account the expected pore water pressure and seismic acceleration. For the Ercengyan landslide , the Limit Equilibrium Method and Strength Reduction Method of FEM are compared through the results of the landslide pressure distributions on the piles and stress fields in the piles. The second component is the study of the required anchor depth of antislide piles, which is carried out using a statistical analysis with data from 20 landslides that have been controlled with anti-sliding piles. The rock characteristics of the anchor locations were obtained using laboratory tests, and a classification of rock mass quality is made for the anchors of antislide piles. The relationship between the critical anchor height and the angle of the landslide slip surface is determined. Two different methods are presented for the length

  4. Effects of Pile Driving on the Residency and Movement of Tagged Reef Fish.

    Directory of Open Access Journals (Sweden)

    Joseph D Iafrate

    Full Text Available The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of pile driving occurring in coastal habitats throughout the world. Behavioral impacts of sound generated from these activities on fish typically have a greater area of influence than physical injury, and may therefore adversely affect a greater portion of the local population. This study used acoustic telemetry to assess the movement, residency, and survival of 15 sheepshead (Archosargus probatocephalus and 10 grey snapper (Lutjanus griseus in Port Canaveral, Florida, USA, in response to 35 days of pile driving at a wharf complex. No obvious signs of mortality or injury to tagged fish were evident from the data. Received sound pressure levels from pile strikes on the interior of the wharf, where reef fish primarily occur, were on average 152-157 dB re 1 μPa (peak. No significant decrease in sheepshead daytime residency was observed during pile driving within the central portion of the wharf and area of highest sound exposure, and no major indicators of displacement from the exposure wharf with the onset of pile driving were observed. There was evidence of potential displacement from the exposure wharf that coincided with the start of pile driving observed for 2 out of 4 grey snapper, along with a decrease in daytime residency for a subset of this species with high site fidelity prior to the event. Results indicate that snapper may be more likely to depart an area of pile driving disturbance more readily than sheepshead, but were less at risk for behavioral impact given the lower site fidelity of this species.

  5. Barrier capability of Zr-N films with titanium addition against copper diffusion

    International Nuclear Information System (INIS)

    Wang Ying; Cao Fei; Yang Xiaodong; Ding Minghui

    2009-01-01

    Zr-Ti-N film prepared by sputtering deposition has been employed as a potential diffusion barrier for Cu metallization. It is thought that the existing states of Ti and Zr in the films are Ti-N and Zr-N phase in Zr-Ti-N films. Material analysis by XRD, XPS and sheet resistance measurement reveal that the failure of Zr-N film is mainly due to the formation of Cu 3 Si precipitates at the Zr-N/Si interface by Cu diffusion through the grain boundaries or local defects of the Zr-N barrier layer into Si substrate. In conjunction with sheet resistance measurement, XRD and XPS analyses, the Cu/Zr-Ti-N/Si contact system has high thermal stability at least up to 700 deg. C. The incorporation of Ti atoms into Zr-N barrier layer was shown to be beneficial in improving the thermal stability of the Cu/barrier/Si contact system.

  6. Are cometary nuclei primordial rubble piles?

    Science.gov (United States)

    Weissman, P. R.

    1986-01-01

    Whipple's icy conglomerate model for the cometary nucleus has had considerable sucess in explaining a variety of cometary phenomena such as gas production rates and nongravitational forces. However, as discussed here, both observational evidence and theoretical considerations suggest that the cometary nucleus may not be a well-consolidated single body, but may instead be a loosely bound agglomeration of smaller fragments, weakly bonded and subject to occasional or even frequent disruptive events. The proposed model is analogous to the 'rubble pile' model suggested for the larger main-belt asteroids, although the larger cometary fragments are expected to be primordial condensations rather than collisionally derived debris as in the asteroid case. The concept of cometary nuclei as primordial rubble piles is proposed as a modification of the basic Whipple model, not as a replacement for it.

  7. Effect of pile-driving sounds on the survival of larval fish

    NARCIS (Netherlands)

    Bolle, L.J.; Jong, C.A.F. de; Bierman, S.M.; Beek, P.J.G. van van; Wessels, P.W.; Blom, E.; Damme, C.J.G. van; Winter, H.V.; Dekeling, R.P.A.

    2016-01-01

    Concern exists about the potential effects of pile-driving sounds on fish, but evidence is limited, especially for fish larvae. A device was developed to expose larvae to accurately reproduced pile-driving sounds. Controlled exposure experiments were carried out to examine the lethal effects in

  8. Towards Intelligent Interpretation of Low Strain Pile Integrity Testing Results Using Machine Learning Techniques.

    Science.gov (United States)

    Cui, De-Mi; Yan, Weizhong; Wang, Xiao-Quan; Lu, Lie-Min

    2017-10-25

    Low strain pile integrity testing (LSPIT), due to its simplicity and low cost, is one of the most popular NDE methods used in pile foundation construction. While performing LSPIT in the field is generally quite simple and quick, determining the integrity of the test piles by analyzing and interpreting the test signals (reflectograms) is still a manual process performed by experienced experts only. For foundation construction sites where the number of piles to be tested is large, it may take days before the expert can complete interpreting all of the piles and delivering the integrity assessment report. Techniques that can automate test signal interpretation, thus shortening the LSPIT's turnaround time, are of great business value and are in great need. Motivated by this need, in this paper, we develop a computer-aided reflectogram interpretation (CARI) methodology that can interpret a large number of LSPIT signals quickly and consistently. The methodology, built on advanced signal processing and machine learning technologies, can be used to assist the experts in performing both qualitative and quantitative interpretation of LSPIT signals. Specifically, the methodology can ease experts' interpretation burden by screening all test piles quickly and identifying a small number of suspected piles for experts to perform manual, in-depth interpretation. We demonstrate the methodology's effectiveness using the LSPIT signals collected from a number of real-world pile construction sites. The proposed methodology can potentially enhance LSPIT and make it even more efficient and effective in quality control of deep foundation construction.

  9. An experimental study on the resistance and movement of short pile installed in sands under horizontal pullout load

    Directory of Open Access Journals (Sweden)

    Oh Kyun Kwon

    2014-03-01

    Full Text Available In this study, the model tests were conducted on the short piles installed in sands under a horizontal pullout load to investigate their behavior characteristics. From the horizontal loading tests where dimensions of the pile diameter and length, and loading point were varied, the horizontal pullout resistance and the rotational and translational movement pattern of the pile were investigated. As a result, the horizontal pullout resistance of the pile embedded in sands was dependent on the pile length, diameter, loading point, etc. The ultimate horizontal pullout load tended to increase as the loading point (h/L moved to the bottom from the top of the pile, regardless of the ratio between the pile length and diameter (L/D, reached the maximum value at the point of h/L = 0.75, and decreased afterwards. When the horizontal pullout load acted on the upper part above the middle of the pile, the pile rotated clockwise and moved to the pullout direction, and the pivot point of the pile was located at 150–360mm depth below the ground surface. On the other hand, when the horizontal pullout load acted on the lower part of the pile, the pile rotated counterclockwise and travelled horizontally, and the rotational angle was very small.

  10. Assessment of Feasibility of Suction Pile/Anchor Installation and Pullout Testing through Field Tests

    Directory of Open Access Journals (Sweden)

    R. Vijaya

    2014-09-01

    Full Text Available Suction pile anchors are large cylindrical (inverted bucket type structure open at the bottom and closed at the top and largely used for mooring of offshore platforms, exploratory vessels etc. Prediction of the mooring capacity of suction piles is a critical issue faced by the design engineers and rational methods are required to produce reliable designs. Tests have been conducted in an existing natural pond within NIOT campus with the objective of developing methodology of deployment, design and logistics for suction pile installation and testing of mooring capacity under static pullout. Small size suction piles with varying diameters and lengths have been used in the tests. The tests have been carried out in the natural pond with constant water depth of 1.5 m with the top 1.5 m layer of bed comprising soft marine clay. It is found that pile geometry, aspect ratio and angle of pullout have a significant influence on the response to pullout. As angle of mooring load application changes from vertical to horizontal the reaction offered by the suction pile changes from skin friction to passive soil resistance. Resistance offered by the internal plug of soil is found to vary according to dimension of the anchor piles.

  11. Asymptotic analysis of a pile-up of regular edge dislocation walls

    KAUST Repository

    Hall, Cameron L.

    2011-12-01

    The idealised problem of a pile-up of regular dislocation walls (that is, of planes each containing an infinite number of parallel, identical and equally spaced dislocations) was presented by Roy et al. [A. Roy, R.H.J. Peerlings, M.G.D. Geers, Y. Kasyanyuk, Materials Science and Engineering A 486 (2008) 653-661] as a prototype for understanding the importance of discrete dislocation interactions in dislocation-based plasticity models. They noted that analytic solutions for the dislocation wall density are available for a pile-up of regular screw dislocation walls, but that numerical methods seem to be necessary for investigating regular edge dislocation walls. In this paper, we use the techniques of discrete-to-continuum asymptotic analysis to obtain a detailed description of a pile-up of regular edge dislocation walls. To leading order, we find that the dislocation wall density is governed by a simple differential equation and that boundary layers are present at both ends of the pile-up. © 2011 Elsevier B.V.

  12. Asymptotic analysis of a pile-up of regular edge dislocation walls

    KAUST Repository

    Hall, Cameron L.

    2011-01-01

    The idealised problem of a pile-up of regular dislocation walls (that is, of planes each containing an infinite number of parallel, identical and equally spaced dislocations) was presented by Roy et al. [A. Roy, R.H.J. Peerlings, M.G.D. Geers, Y. Kasyanyuk, Materials Science and Engineering A 486 (2008) 653-661] as a prototype for understanding the importance of discrete dislocation interactions in dislocation-based plasticity models. They noted that analytic solutions for the dislocation wall density are available for a pile-up of regular screw dislocation walls, but that numerical methods seem to be necessary for investigating regular edge dislocation walls. In this paper, we use the techniques of discrete-to-continuum asymptotic analysis to obtain a detailed description of a pile-up of regular edge dislocation walls. To leading order, we find that the dislocation wall density is governed by a simple differential equation and that boundary layers are present at both ends of the pile-up. © 2011 Elsevier B.V.

  13. Retrofitting Of RCC Piles By Using Basalt Fiber Reinforced Polymer BFRP Composite Part 1 Review Papers On RCC Structures And Piles Retrofitting Works.

    OpenAIRE

    R. Ananda Kumar; Dr. C. Selvamony; A. Seeni; Dr. T. R. Sethuraman

    2015-01-01

    Abstract Retrofitting works are immensely essential for deteriorated and damaged structures in Engineering and Medical fields in order to keep or return to the originality for safe guarding the structures and consumers. In this paper different types of methods of retrofitting review notes are given based on the experimental numerical and analytical methods results on strengthening the Reinforced cement concrete RCC structures including RCC piles. Soil-pile interaction on axial load lateral lo...

  14. Effects of Diameter on Initial Stiffness of P-Y Curves for Large-Diameter Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo; Augustesen, Anders Hust

    2010-01-01

    is developed for slender piles with diameters up to approximately 2.0 m. Hence, the method is not validated for piles with diameters of 4–6 m. The aim of the paper is to extend the p-y curve method to large-diameter non-slender piles in sand by considering the effects of the pile diameter on the soil-pile...... interaction. Hence, a modified expression for the p-y curves for statically loaded piles in sand is proposed in which the initial slope of the p-y curves depends on the depth below the soil surface, the pile diameter and the internal angle of friction. The evaluation is based on three-dimensional numerical...... analyses by means of the commercial program FLAC3D incorporating a Mohr-Coulomb failure criterion. The numerical model is validated with laboratory tests in a pressure tank at Aalborg University....

  15. Recent hydrological observations from the Riverton and Maybell tailings piles

    International Nuclear Information System (INIS)

    Tokunaga, T.; Narasimhan, T.N.

    1982-01-01

    This paper reports on field and laboratory hydrologic studies of two inactive uranium mill tailings piles under the Uranium Mill Tailings Remedial Action Program (UMTRA). The ultimate goal of the studies is to evaluate the nature of the contaminant potential of the piles with sufficient detail so that appropriate remedial measures can be designed and implemented under the UMTRA Program. The field studies included the monitoring of hydraulic head profiles of the piles and infiltration tests. Both the field and laboratory results from the Riverton tailings indicate a great deal of spatial variability in hydraulic properties. It is determined that the bulk of the precipitation input at the Riverton tailings is lost by evapotranspiration within the upper meter of soil cover and tailings

  16. Spontaneous vegetation on overburden piles in the Coal Basin of Santa Catarina, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    dos Santos, R.; Citadini-Zanette, V.; Leal-Filho, L.S.; Hennies, W.T. [University of Extremo Sul Catarinense, Criciuma (Brazil)

    2008-09-15

    The objective of this work was to select indigenous vegetal species for restoration programs aiming at the regeneration of ombrophilous dense forest. Thirty-five spoil piles located in the county of Sideropolis, Santa Catarina, that received overburden disposal for 39 years (1950-1989) were selected for study because they exhibited remarkable spontaneous regrowth of trees compared to surrounding spoil piles. Floristic inventory covered the whole area of the 35 piles, whereas survey on phytosociology and natural regeneration studies were conducted in 70 plots distributed along the 35 piles. Floristic inventory recorded 83 species from 28 botanical families. Herbaceous terricolous plants constituted the predominant species (47.0%), followed by shrubs (26.5%), trees (19.3%), and vines (7.2%). Severe chemical (acidic pH and lack of nutrients) and physical (coarse substrate and slope angle of 40-50{sup o} characteristics displayed by the overburden piles constituted limitations to floristic diversity and size of indigenous trees, indicating the need for substrate reclamation prior to forest restoration.

  17. Design and Preparation of Carbon Based Composite Phase Change Material for Energy Piles

    Science.gov (United States)

    Yang, Haibin; Memon, Shazim Ali; Bao, Xiaohua; Cui, Hongzhi; Li, Dongxu

    2017-01-01

    Energy piles—A fairly new renewable energy concept—Use a ground heat exchanger (GHE) in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs) to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs (expanded graphite-based PCM and graphite nanoplatelet-based PCM) were prepared by vacuum impregnation for potential application in energy piles. Thereafter, a systematic study was performed and different characterization tests were carried out on two composite PCMs. The composite PCMs retained up to 93.1% of paraffin and were chemically compatible, thermally stable and reliable. The latent heat of the composite PCM was up to 152.8 J/g while the compressive strength of cement paste containing 10 wt % GNP-PCM was found to be 37 MPa. Hence, the developed composite PCM has potential for thermal energy storage applications. PMID:28772752

  18. STABILIZATION OF A FAILED SLOPE WITH PILED STRUCTURES

    Directory of Open Access Journals (Sweden)

    M. Rifat KAHYAOĞLU

    2008-01-01

    Full Text Available Neogene aged units of a densely populated region of Western Turkey along the Aegean Sea coastline is susceptible to landslides causing frequent economic loss especially following raining seasons. Several landslides took place in the area covering a narrow band of the coastline between Izmir and Söke (Aydın. Countermeasures against these relatively small-scale slope failures in the region often involve construction of either reinforced concrete retaining walls or stabilizing piles, which can be easily constructed by local contractors. In this study borings, in-situ and laboratory soil mechanics tests, geophysical and geological investigations have been performed in order to investigate the landslide occurred in the yard of an elementary school in Söke township. The analysis of two rows of piled retaining system constructed to reuse the school building against a potential slides are presented. Three inclinometer measurements have been performed after completion of the bored pile system. It has been concluded that the measured and the calculated displacement values are both small. There is no problem of the built project by means of moments and displacements.

  19. Comparison of Design Methods for Axially Loaded Driven Piles in Cohesionless Soil

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2012-01-01

    For offshore wind turbines on deeper waters, a jacket sub-structure supported by axially loaded piles is thought to be the most suitable solution. The design method recommended by API and two CPT-based design methods are compared for two uniform sand profiles. The analysis show great difference...... in the predictions of bearing capacities calculated by means of the three methods for piles loaded in both tension and compression. This implies that further analysis of the bearing capacity of axially loaded piles in sand should be conducted....

  20. Mathematical Model and Analysis of Negative Skin Friction of Pile Group in Consolidating Soil

    Directory of Open Access Journals (Sweden)

    Gangqiang Kong

    2013-01-01

    Full Text Available In order to calculate negative skin friction (NSF of pile group embedded in a consolidating soil, the dragload calculating formulas of single pile were established by considering Davis one-dimensional nonlinear consolidation soils settlement and hyperbolic load-transfer of pile-soil interface. Based on effective influence area theory, a simple semiempirical mathematical model of analysis for predicting the group effect of pile group under dragload was described. The accuracy and reliability of mathematical models built in this paper were verified by practical engineering comparative analysis. Case studies were studied, and the prediction values were found to be in good agreement with those of measured values. Then, the influences factors, such as, soil consolidation degree, the initial volume compressibility coefficient, and the stiffness of bearing soil, were analyzed and discussed. The results show that the mathematical models considering nonlinear soil consolidation and group effect can reflect the practical NSF of pile group effectively and accurately. The results of this paper can provide reference for practical pile group embedded in consolidating soil under NSF design and calculation.

  1. A new method for testing pile by single-impact energy and P-S curve

    Science.gov (United States)

    Xu, Zhao-Yong; Duan, Yong-Kang; Wang, Bin; Hu, Yi-Li; Yang, Run-Hai; Xu, Jun; Zhao, Jin-Ming

    2004-11-01

    By studying the pile-formula and stress-wave methods ( e.g., CASE method), the authors propose a new method for testing piles using the single-impact energy and P-S curves. The vibration and wave figures are recorded, and the dynamic and static displacements are measured by different transducers near the top of piles when the pile is impacted by a heavy hammer or micro-rocket. By observing the transformation coefficient of driving energy (total energy), the consumed energy of wave motion and vibration and so on, the vertical bearing capacity for single pile is measured and calculated. Then, using the vibration wave diagram, the dynamic relation curves between the force ( P) and the displacement ( S) is calculated and the yield points are determined. Using the static-loading test, the dynamic results are checked and the relative constants of dynamic-static P-S curves are determined. Then the subsidence quantity corresponding to the bearing capacity is determined. Moreover, the shaped quality of the pile body can be judged from the formation of P-S curves.

  2. The effect of pulse pile-up on discrimination between neutrons and gamma rays

    International Nuclear Information System (INIS)

    Whittlestone, S.

    1980-01-01

    Pulse pile-up lengthens the rise-time of pulses. With an organic scintillator such as NE 213, pile-up can cause a short rise-time pulse originating from gamma rays to be interpreted by a rise-time analyser as a neutron. The degradation of pulse shape analyser performance at high count rates is shown to be directly related to pulse pile-up. Using this relationship, the contribution of piled-up gamma rays and neutrons to count rate related errors is calculated for a time-dependent fast neutron energy spectrum measurement. Errors of a few per cent occur even when the probability of a count per burst is as low as 0.01. (orig.)

  3. Assessment of cover systems at the Grand Junction, Colorado, uranium mill tailings pile: 1987 field measurements

    International Nuclear Information System (INIS)

    Gee, G.W.; Campbell, M.D.; Freeman, H.D.; Cline, J.F.

    1989-02-01

    Four Pacific Northwest Laboratory (PNL) scientists and a technician conducted an onsite evaluation of radon gas exhalation, water content profiles, and plant and animal intrusion for a series of cover systems located on the uranium mill tailings pile at Grand Junction, Colorado. These six plots were sampled extensively down to the radon control layer (e.g., asphalt or wet clay) for soil moisture content and permeability. Radon gas emission through the surface was measured. Soil samples were collected and analyzed in the lab for particle-size distribution, particle density, bulk density, and ambient water content. Prairie dog burrows were excavated to discover the extent to which they penetrated the barriers. Plant type, density, and cover characteristics were measured

  4. Barytes board: a cost effective radiation barrier material for use in diagnostic x-ray suites

    International Nuclear Information System (INIS)

    Coalter, G.C.; Metcalfe, P.E.

    1987-01-01

    The use of barium based products in protective barrier materials proved successful for many years until their cost of manufacture and increases in labour costs for fixing and stopping saw the introduction of lead ply as the material of choice in diagnostic X-ray suites. Whilst the advantage of sheet lead as a barrier for diagnostic X-rays, where the photoelectric effect predominates is recognised, this precedence is somewhat negated by the high cost of manufacture and delays in supply. Lead lined ply also requires external cladding after erection for an acceptable finish to be obtained. Such cost increases have prompted us to re-evaluate the use of precast barium plaster sheets (Barytes Board) as an alternative barrier material

  5. Displacement pile installation effects in sand

    NARCIS (Netherlands)

    Beijer-Lundberg, A.

    2015-01-01

    Installation effects govern the post-installation behaviour of displacement piles in sand. These effects are currently not completely understood. Suitable experimental techniques to model these installation effects include field, laboratory and experimental models. In the current thesis a

  6. Reliability techniques and Coupled BEM/FEM for interaction pile-soil

    Directory of Open Access Journals (Sweden)

    Ahmed SAHLI

    2017-06-01

    Full Text Available This paper deals with the development of a computational code for the modelling and verification of safety in relation to limit states of piles found in foundations of current structures. To this end, it makes use of reliability techniques for the probabilistic analysis of piles modelled with the finite element method (FEM coupled to the boundary element method (BEM. The soil is modelled with the BEM employing Mindlin's fundamental solutions, suitable for the consideration of a three-dimensional infinite half-space. The piles are modelled as bar elements with the MEF, each of which is represented in the BEM as a loading line. The finite element of the employed bar has four nodes and fourteen nodal parameters, three of which are displacements for each node plus two rotations for the top node. The slipping of the piles in relation to the mass is carried out using adhesion models to define the evolution of the shaft tensions during the transfer of load to the soil. The reliability analysis is based on three methods: first order second moment (FOSM, first order reliability method and Monte Carlo method.

  7. Neutron spectrum in small iron pile surrounded by lead reflector

    International Nuclear Information System (INIS)

    Kimura, Itsuro; Hayashi, S.A.; Kobayashi, Katsuhei; Matsumura, Tetsuo; Nishihara, Hiroshi.

    1978-01-01

    In order to save the quantity of sample material, a possibility to assess group constants of a reactor material through measurement and analysis of neutron spectrum in a small sample pile surrounded by a reflector of heavy moderator, was investigated. As the sample and the reflector, we chose iron and lead, respectively. Although the time dispersion in moderation of neutrons was considerably prolonged by the lead reflector, this hardly interferes with the assessment of group constants. Theoretical calculation revealed that both the neutron flux spectrum and the sensitivity coefficient of group constants in an iron sphere, 35 cm in diameter surrounded by the lead reflector, 25 cm thick, were close to those of the bare iron sphere, 108 cm in diameter. The neutron spectra in a small iron pile surrounded by a lead reflector were experimentally obtained by the time-of-flight method with an electron linear accelerator and the result was compared with the predicted values. It could be confirmed that a small sample pile surrounded by a reflector, such as lead, was as useful as a much larger bulk pile for the assessment of group constants of a reactor material. (auth.)

  8. Recovery of small pile burn scars in conifer forests of the Colorado Front Range

    Science.gov (United States)

    Charles C. Rhoades; Paula J. Fornwalt; Mark W. Paschke; Amber Shanklin; Jayne L. Jonas

    2015-01-01

    The ecological consequences of slash pile burning are a concern for land managers charged with maintaining forest soil productivity and native plant diversity. Fuel reduction and forest health management projects have created nearly 150,000 slash piles scheduled for burning on US Forest Service land in northern Colorado. The vast majority of these are small piles (

  9. Rehabilitating slash pile burn scars in upper montane forests of the Colorado Front Range

    Science.gov (United States)

    Paula J. Fornwalt; Charles C. Rhoades

    2011-01-01

    Slash pile burning is widely conducted by land managers to dispose of unwanted woody fuels, yet this practice typically has undesirable ecological impacts. Simple rehabilitation treatments may be effective at ameliorating some of the negative impacts of pile burning on plants and soils. Here, we investigated: (1) the impacts of slash pile burning on soil nitrogen and...

  10. Uranium migration and retention during weathering of a granitic waste rock pile

    International Nuclear Information System (INIS)

    Boekhout, F.; Gérard, M.; Kanzari, A.; Michel, A.; Déjeant, A.; Galoisy, L.; Calas, G.; Descostes, M.

    2015-01-01

    Highlights: • We investigate the environmental impact of the granitic waste rock piles. • The majority of the waste rocks in the pile is barren- or overburden rock. • The main neo-formed U-bearing phases are (Ca) and (Cu) uranyl phosphates. • Under circum-neutral pH conditions they do not pose an environment threat. - Abstract: This study investigates the post-mining evolution of S-type granitic waste rocks around a former uranium mine, Vieilles Sagnes (Haute Vienne, NW Massif Central, France). This mine was operated between 1957 and 1965 in the La Crouzille former world-class uranium mining district and is representative of intra-granitic vein-type deposits. 50 years after mine closure and the construction and subsequent re-vegetation of the granitic waste rock pile, we evaluate the environmental evolution of the rock pile, including rock alteration, neo-formation of U-bearing phases during weathering, and U migration. Vertical trenches have been excavated through the rock pile down to an underlying paleo-soil, allowing the investigation of the vertical differentiation of the rock pile and its influence on water pathways, weathering processes and U migration and retention. Arenization dominantly drives liberation of U, by dissolution of uraninite inclusions in the most alterable granitic minerals (i.e. K-feldspar and biotite). Retention of U in the matrix at the base of the waste rock pile, and in the underlying paleo-soil most likely occurs by precipitation of (nano-) uranyl phosphates or a combination of co-precipitation and adsorption reactions of U onto Fe (oxy)hydroxides and/or clay minerals. Even though U-migration was observed, U is retained in stable secondary mineral phases, provided the current conditions will not be modified

  11. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    Energy Technology Data Exchange (ETDEWEB)

    Testa, M., E-mail: marianna.testa@lnf.infn.it

    2016-07-11

    The large rate of multiple simultaneous proton–proton interactions, or pile-up, generated by the Large Hadron Collider in Run 1 required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are presented here. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  12. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    International Nuclear Information System (INIS)

    Testa, M.

    2016-01-01

    The large rate of multiple simultaneous proton–proton interactions, or pile-up, generated by the Large Hadron Collider in Run 1 required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are presented here. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  13. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    CERN Document Server

    Testa, Marianna; The ATLAS collaboration

    2015-01-01

    The large rate of multiple simultaneous proton-proton interactions, or pile-up, generated by the Large Hadron Collider in Run I required the development of many new techniques to mitigate the adverse effects of these conditions. The methods employed to correct for the impact of pile-up on jet energy, shapes and multiplicity with the ATLAS detector are here presented. They include energy correction techniques based on estimates of the average pile-up energy density and jet-to-vertex association techniques. Extensions of these methods to reduce the impact of pile-up on jet shapes use both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC are also shown.

  14. Dynamic stiffness and seismic input motion of a group of battered piles

    International Nuclear Information System (INIS)

    Wolf, J.P.

    1979-01-01

    The dynamic stiffness (impedance function) and the corresponding seismic input motion of a group of battered piles, which can be end-bearing and floating, situated in any desired configuration in horizontally stratified soil, are determined. The soil and the piles consist of (frequency-dependent) visco-elastic material with hysteretic damping. The base mat can be rigid or flexible. Any seismic excitation, for which the free-field motion can be calculated, can be specified (body waves, propagating at an arbitrary angle, generalized surface waves). The soil is discretized by toroidal finite elements in conjunction with a Fourier expansion in the circumferential direction. Radiation and hysteretic damping are accounted for. The dynamic-flexibility matrix of the soil is generated, superimposing the basic dynamic-flexibility coefficients calculated by applying sequentially a horizontal and a vertical force at all nodes located on the axis of symmetry. The influence of the soil which is subsequently replaced by piles is taken into consideration. Pile-soil-pile interaction is accounted for in this method. The formulation can also be applied to embedded foundation and buried structures such as tunnels and pipe systems. (Auth.)

  15. Decommissioning and dismantling of 305-M test pile at the Savannah River Plant

    International Nuclear Information System (INIS)

    Horton, H.L.

    1985-01-01

    The 305-M Test Pile was started up at the Savannah River Plant in 1952 and operated until 1981. The pile was used to measure the uranium content of reactor fuel. In 1984 work began to decommission and dismantle the pile. Extensive procedures were used that included a detailed description of the radiological controls and safety measures. These controls allowed the job to be completed with radiation doses as low as reasonably achievable

  16. Applicability of Various Load Test Interpretation Criteria in Measuring Driven Precast Concrete Pile Uplift Capacity

    Directory of Open Access Journals (Sweden)

    Maria Cecilia M. Marcos

    2018-04-01

    Full Text Available This paper presented a comprehensive analysis of load test interpretation criteria to determine their suitability to driven precast concrete (PC pile uplift capacity. A database was developed containing static pile load tests and utilized for the evaluation. The piles were round and square cross-sections under drained and undrained loading. To explore and compare their behavior, the stored data were categorized into four groups. In general, the trends of every criterion for the four groups were notably the same. In both drained and undrained loading, slightly larger interpreted capacities were demonstrated by square piles than by round piles. Moreover, round piles demonstrated more ductile load-displacement response than square piles especially in undrained loading. Statistical analyses presented that smaller values of displacements exhibited higher coefficient of variation. The drained and undrained tests were compared and results showed less variability in drained than undrained loading and capacity ratios (Qx/QCHIN in drained loading were slightly higher than in undrained loading. The interrelationship and applicability of these criteria as well as the design recommendations in terms of normalized capacity and displacement were given based on the analyses.

  17. Constituent-level pile-up mitigation techniques in ATLAS

    CERN Document Server

    The ATLAS collaboration

    2017-01-01

    Pile-up of simultaneous proton-proton collisions at the LHC has a significant impact on jet reconstruction. In this note the performance of several pile-up mitigation techniques is evaluated in detailed simulations of the ATLAS experiment. Four algorithms that act on the jet-constituent level are evaluated: SoftKiller, the cluster vertex fraction algorithm and Voronoi and constituent subtraction. We find that application of these constituent-level algorithms improves the resolution of low-transverse-momentum jets. The improvement is significant for collisions with 80-200 simultaneous proton-proton collisions envisaged in future runs of the LHC.

  18. Centrifuge modelling of a laterally cyclic loaded pile

    DEFF Research Database (Denmark)

    Klinkvort, Rasmus Tofte; Leth, Caspar Thrane; Hededal, Ole

    2010-01-01

    A total number of 9 static and 6 cyclic centrifuge tests on laterally loaded piles in very dense, dry sand was erformed. The prototype dimensions of the piles were 1 meter in diameter and penetration depths varying from 6 to 10 meters. The static tests were used to investigate the initial subgrade...... reaction modulus and as a reference for cyclic tests. For the cyclic tests the accumulation of deflections and the change in secant stiffness of the soil from repetitive loading were investigated. From all the tests carried out accumulations of deflections were seen. rom the centrifuge tests it was seen...

  19. Field monitoring of static, dynamic, and statnamic pile loading tests using fibre Bragg grating strain sensors

    Science.gov (United States)

    Li, Jin; Correia, Ricardo P.; Chehura, Edmon; Staines, Stephen; James, Stephen W.; Tatam, Ralph; Butcher, Antony P.; Fuentes, Raul

    2009-10-01

    Pile loading test plays an important role in the field of piling engineering. In order to gain further insight into the load transfer mechanism, strain gauges are often used to measure local strains along the piles. This paper reports a case whereby FBG strain sensors was employed in a field trial conducted on three different types of pile loading tests in a glacial till. The instrumentation systems were configured to suit the specific characteristic of each type of test. Typical test results are presented. The great potential of using FBG sensors for pile testing is shown.

  20. Determination of rheological parameters of pile foundations for bridges for earthquake analysis

    Science.gov (United States)

    1997-07-01

    In the seismic design criteria for highway bridges, there is a significant lack of guidance on ways to incorporate the effect of soil-structure interaction in determining seismic response. For this study, a simple analytical model for pile and pile g...

  1. Mineralogical and micromorphological modifications in soil affected by slash pile burn

    Science.gov (United States)

    M. M. Nobles; W. J. Massman; M. Mbila; G. Butters

    2010-01-01

    Silvicultural practices, such as slash pile burning, are commonly used for fire and ecosystem management. This management technique can drastically alter chemical, physical and biological soil properties due to the high temperatures achieved during the prolonged severe burn. Little is known, however, about the impact of high-temperature slash pile burning on soil...

  2. Design criteria and fabrication in-pile test section of HANARO fuel test loop

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. Y.

    1997-10-01

    Safety state fuel test loop will be equipped in HANARO to obtain the development and betterments of advanced fuel and materials through the irradiation tests. The objective of this study is to determine the design criteria and technical specification of in-pile test section and to specify the manufacturing requirements of in-pile test section. HANARO fuel test loop was designed to meet the CANDU and PWR fuel testing and in-pile section will be manufactured and installed in HANARO. The design criteria and technical specification of in-pile test section could be used the fuel and materials design with for irradiation testing IPS of HANARO fuel test loop. This results will become guidances for the planning and programming of irradiation testing. (author). 12 refs., tabs., figs.

  3. Clinical efficacy of Jalaukawacharana (leech application) in Thrombosed piles.

    Science.gov (United States)

    Bhagat, Pradnya J; Raut, Subhash Y; Lakhapati, Arun M

    2012-04-01

    'Arsha' (hemorrhoids) is an ailment that affects all economical groups of population. Though the disease is within the limits of management, it has its own complications like severe hemorrhage, inflammation, and thrombosis, by which a patient gets severe pain and is unable to continue his routine work. Prior to surgical treatment of hemorrhoids, associated conditions like inflammation, strangulation, thrombosis, etc. need to be managed. Thrombosed piles possibly occur due to high venous pressure associated with severe anal pain. Leech (Hirudina medicanalis) application is found to be effective in reducing pain. In thrombosed piles, leech application has shown thrombolytic action, which contributes in re-establishment of circulation. It is observed in the study that, pus and mucous discharge have been reduced after leech application; which may be due to antimicrobial and mucolytic properties of leech. This method of treatment is found to be effective and increase the quality of life in patients suffering with thrombosed piles.

  4. Enhanced in-pile instrumentation at the advanced test reactor

    Energy Technology Data Exchange (ETDEWEB)

    Rempe, J. L.; Knudson, D. L.; Daw, J. E.; Unruh, T.; Chase, B. M.; Palmer, J.; Condie, K. G.; Davis, K. L. [Idaho National Laboratory, MS 3840, P.O. Box 1625, Idaho Falls, ID 83415 (United States)

    2011-07-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory. To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility in 2007 to support the development and deployment of enhanced in-pile sensors. This paper reports results from this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and realtime flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted. (authors)

  5. Enhanced In-Pile Instrumentation at the Advanced Test Reactor

    Science.gov (United States)

    Rempe, Joy L.; Knudson, Darrell L.; Daw, Joshua E.; Unruh, Troy; Chase, Benjamin M.; Palmer, Joe; Condie, Keith G.; Davis, Kurt L.

    2012-08-01

    Many of the sensors deployed at materials and test reactors cannot withstand the high flux/high temperature test conditions often requested by users at U.S. test reactors, such as the Advanced Test Reactor (ATR) at the Idaho National Laboratory. To address this issue, an instrumentation development effort was initiated as part of the ATR National Scientific User Facility in 2007 to support the development and deployment of enhanced in-pile sensors. This paper provides an update on this effort. Specifically, this paper identifies the types of sensors currently available to support in-pile irradiations and those sensors currently available to ATR users. Accomplishments from new sensor technology deployment efforts are highlighted by describing new temperature and thermal conductivity sensors now available to ATR users. Efforts to deploy enhanced in-pile sensors for detecting elongation and real-time flux detectors are also reported, and recently-initiated research to evaluate the viability of advanced technologies to provide enhanced accuracy for measuring key parameters during irradiation testing are noted.

  6. A Systematic Approach for Determining Vertical Pile Depth of Embedment in Cohensionless Soils to Withstand Lateral Barge Train Impact Loads

    Science.gov (United States)

    2017-01-30

    at the top of the piles, vertical pile groups must be designed to exhibit long-pile behavior (e.g., nominal change of deflection at the pile cap...smeared crack” pile properties (and thus, the advisability of using COM624G for analysis) for the incremental pushover design method, as compared...to show nominal change as the pile-tip depth is increased. This same behavior should exist for piles in any homogeneous, cohesionless soil. From

  7. Analytical Method Used to Calculate Pile Foundations with the Widening Up on a Horizontal Static Impact

    Science.gov (United States)

    Kupchikova, N. V.; Kurbatskiy, E. N.

    2017-11-01

    This paper presents a methodology for the analytical research solutions for the work pile foundations with surface broadening and inclined side faces in the ground array, based on the properties of Fourier transform of finite functions. The comparative analysis of the calculation results using the suggested method for prismatic piles, piles with surface broadening prismatic with precast piles and end walls with precast wedges on the surface is described.

  8. Performance of pile-up mitigation techniques for jets in pp collisions with the ATLAS detector

    CERN Document Server

    Testa, Marianna; The ATLAS collaboration

    2015-01-01

    The large rate of multiple simultaneous proton-proton interactions, or pile-up, generated by the Large Hadron Collider in Run I required the development of many new techniques to mitigate the adverse effects of these conditions. This presentation shows the methods employed to correct for the impact of pile-up on jet energy, jet shapes, and even spurious additional jets. Energy correction techniques that incorporate sophisticated estimates of the average pile-up energy density and tracking information are described in detail. Jet-to-vertex association techniques are also presented. We also describe the extension of these techniques to ameliorate the effect of pile-up on jet shapes using both subtraction and grooming procedures. Prospects for pile-up suppression at the HL-LHC will be also discussed.

  9. Analysis of Driven Pile Capacity within Pre-Bored Soil : Research Project Capsule

    Science.gov (United States)

    2017-10-01

    Pre-boring is a method used to facilitate large displacement pile driving in hard/dense soils (see Figure 1). By pre-boring a pilot hole, the end bearing and side friction within the pre-bored zone are reduced, thus aiding pile driving installation. ...

  10. Development of In-pile Plug Assembly and Primary Shutter for Cold Neutron Guide System

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jin Won; Cho, Yeong Garp; Ryu, Jeong Soo; Lee, Jung Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-12-15

    The HANARO, a 30 MW multi-purpose research reactor in Korea, will be equipped with a neutron guide system, in order to transport cold neutrons from the neutron source to the neutron scattering instruments in the neutron guide hall near the reactor building. The neutron guide system of HANARO consists of the in-pile plug assembly with in-pile guides, the primary shutter with in-shutter guides, the neutron guides in the guide shielding room with dedicated secondary shutters, and the neutron guides connected to the instruments in the neutron guide hall. The functions of the in-pile plug assembly are to shield the reactor environment from a nuclear radiation and to support the neutron guides and maintain them precisely oriented. The primary shutter is a mechanical device to be installed just after the in-pile plug assembly, which stops neutron flux on demand. This report describes the mechanical design, fabrication, and installation procedure of the in-pile plug assembly and the primary shutter for the neutron guide system at HANARO. A special tool and procedure for a replacement of in-pile plug and guide cassette is also presented with the interface condition in the reactor hall.

  11. Design and Preparation of Carbon Based Composite Phase Change Material for Energy Piles

    Directory of Open Access Journals (Sweden)

    Haibin Yang

    2017-04-01

    Full Text Available Energy piles—A fairly new renewable energy concept—Use a ground heat exchanger (GHE in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs (expanded graphite-based PCM and graphite nanoplatelet-based PCM were prepared by vacuum impregnation for potential application in energy piles. Thereafter, a systematic study was performed and different characterization tests were carried out on two composite PCMs. The composite PCMs retained up to 93.1% of paraffin and were chemically compatible, thermally stable and reliable. The latent heat of the composite PCM was up to 152.8 J/g while the compressive strength of cement paste containing 10 wt % GNP-PCM was found to be 37 MPa. Hence, the developed composite PCM has potential for thermal energy storage applications.

  12. Simplified Model for the Hybrid Method to Design Stabilising Piles Placed at the Toe of Slopes

    Directory of Open Access Journals (Sweden)

    Dib M.

    2018-01-01

    Full Text Available Stabilizing precarious slopes by installing piles has become a widespread technique for landslides prevention. The design of slope-stabilizing piles by the finite element method is more accurate comparing to the conventional methods. This accuracy is because of the ability of this method to simulate complex configurations, and to analyze the soil-pile interaction effect. However, engineers prefer to use the simplified analytical techniques to design slope stabilizing piles, this is due to the high computational resources required by the finite element method. Aiming to combine the accuracy of the finite element method with simplicity of the analytical approaches, a hybrid methodology to design slope stabilizing piles was proposed in 2012. It consists of two steps; (1: an analytical estimation of the resisting force needed to stabilize the precarious slope, and (2: a numerical analysis to define the adequate pile configuration that offers the required resisting force. The hybrid method is applicable only for the analysis and the design of stabilizing piles placed in the middle of the slope, however, in certain cases like road constructions, piles are needed to be placed at the toe of the slope. Therefore, in this paper a simplified model for the hybrid method is dimensioned to analyze and design stabilizing piles placed at the toe of a precarious slope. The validation of the simplified model is presented by a comparative analysis with the full coupled finite element model.

  13. Study on Load-Bearing Characteristics of a New Pile Group Foundation for an Offshore Wind Turbine

    Directory of Open Access Journals (Sweden)

    Ruiqing Lang

    2014-01-01

    Full Text Available Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect.

  14. Study on load-bearing characteristics of a new pile group foundation for an offshore wind turbine.

    Science.gov (United States)

    Lang, Ruiqing; Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect.

  15. Study on Load-Bearing Characteristics of a New Pile Group Foundation for an Offshore Wind Turbine

    Science.gov (United States)

    Liu, Run; Lian, Jijian; Ding, Hongyan

    2014-01-01

    Because offshore wind turbines are high-rise structures, they transfer large horizontal loads and moments to their foundations. One of the keys to designing a foundation is determining the sensitivities and laws affecting its load-bearing capacity. In this study, this procedure was carried out for a new high-rise cap pile group foundation adapted to the loading characteristics of offshore wind turbines. The sensitivities of influential factors affecting the bearing properties were determined using an orthogonal test. Through a combination of numerical simulations and model tests, the effects of the inclination angle, length, diameter, and number of side piles on the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity were determined. The results indicate that an increase in the inclination angle of the side piles will increase the vertical bearing capacity, horizontal bearing capacity, and bending bearing capacity. An increase in the length of the side piles will increase the vertical bearing capacity and bending bearing capacity. When the length of the side piles is close to the central pile, the increase is more apparent. Finally, increasing the number of piles will increase the horizontal bearing capacity; however, the growth rate is small because of the pile group effect. PMID:25250375

  16. Relaxation Dynamics of a Granular Pile on a Vertically Vibrating Plate

    Science.gov (United States)

    Tsuji, Daisuke; Otsuki, Michio; Katsuragi, Hiroaki

    2018-03-01

    Nonlinear relaxation dynamics of a vertically vibrated granular pile is experimentally studied. In the experiment, the flux and slope on the relaxing pile are measured by using a high-speed laser profiler. The relation of these quantities can be modeled by the nonlinear transport law assuming the uniform vibrofluidization of an entire pile. The fitting parameter in this model is only the relaxation efficiency, which characterizes the energy conversion rate from vertical vibration into horizontal transport. We demonstrate that this value is a constant independent of experimental conditions. The actual relaxation is successfully reproduced by the continuity equation with the proposed model. Finally, its specific applicability toward an astrophysical phenomenon is shown.

  17. Design method of large-diameter rock-socketed pile with steel casing

    Science.gov (United States)

    Liu, Ming-wei; Fang, Fang; Liang, Yue

    2018-02-01

    There is a lack of the design and calculation method of large-diameter rock-socketed pile with steel casing. Combined with the “twelfth five-year plan” of the National Science & Technology Pillar Program of China about “Key technologies on the ports and wharfs constructions of the mountain canalization channels”, this paper put forward the structured design requirements of concrete, steel bar distribution and steel casing, and a checking calculation method of the bearing capacity of the normal section of the pile and the maximum crack width at the bottom of the steel casing. The design method will have some degree of guiding significance for the design of large-diameter rock-socketed pile with steel casing.

  18. Earthquakes - dynamic loads on the foundation piles of a nuclear reactor

    International Nuclear Information System (INIS)

    Henning, F.; Dufour, C.; Fuzier, J.P.; Cheyrezy, M.

    1976-01-01

    The purpose of this paper is to analyse the behaviour of a piled foundation of a nuclear power plant submitted to earthquake loadings. The actual horizontal stiffness of the compound 'soil + structure' is calculated from the stiffness of the piles and the dynamic characteristics of the different layers of soil. The maximum amplitude of the horizontal displacement of the raft foundation is obtained by an iterative calculation from the displacement spectrum applied to the surrounding earth. At this stage, the moment diagrams for the different types of piles and their required reinforcement are calculated. The response of the nuclear plant components is determined from the displacement spectrum previously obtained for the raft. (author)

  19. Shake table test of soil-pile groups-bridge structure interaction in liquefiable ground

    Science.gov (United States)

    Tang, Liang; Ling, Xianzhang; Xu, Pengju; Gao, Xia; Wang, Dongsheng

    2010-03-01

    This paper describes a shake table test study on the seismic response of low-cap pile groups and a bridge structure in liquefiable ground. The soil profile, contained in a large-scale laminar shear box, consisted of a horizontally saturated sand layer overlaid with a silty clay layer, with the simulated low-cap pile groups embedded. The container was excited in three El Centro earthquake events of different levels. Test results indicate that excessive pore pressure (EPP) during slight shaking only slightly accumulated, and the accumulation mainly occurred during strong shaking. The EPP was gradually enhanced as the amplitude and duration of the input acceleration increased. The acceleration response of the sand was remarkably influenced by soil liquefaction. As soil liquefaction occurred, the peak sand displacement gradually lagged behind the input acceleration; meanwhile, the sand displacement exhibited an increasing effect on the bending moment of the pile, and acceleration responses of the pile and the sand layer gradually changed from decreasing to increasing in the vertical direction from the bottom to the top. A jump variation of the bending moment on the pile was observed near the soil interface in all three input earthquake events. It is thought that the shake table tests could provide the groundwork for further seismic performance studies of low-cap pile groups used in bridges located on liquefiable groun.

  20. Reconfigurable origami sonic barriers with tunable bandgaps for traffic noise mitigation

    Science.gov (United States)

    Thota, M.; Wang, K. W.

    2017-10-01

    An origami sonic barrier composed of cylindrical inclusions attached onto an origami sheet is proposed. The idea allows for tunable sound blocking properties for application in attenuating complex traffic noise spectra. Folding of the underlying origami sheet transforms the periodicity of the inclusions between different Bravais lattices, viz. between a square and a hexagonal lattice, and such significant lattice re-configuration leads to drastic tuning of dispersion characteristics. The wave tuning capabilities are corroborated via performing theoretical and numerical investigations using a plane wave expansion method and an acoustic simulation package of COMSOL, while experiments are performed on a one-seventh scaled-down model of origami sonic barrier to demonstrate the lattice re-configuration between different Bravais lattices and the associated bandgap adaptability. Good sound blocking performance in the frequency range of traffic noise spectra combined with less efforts, required for actuating one-degree of freedom folding mechanism, makes the origami sonic barrier a potential candidate for mitigating complex traffic noise.

  1. Static Test and Result Analysis on Different Types of Pile Composite Foundation in the Same Field

    Directory of Open Access Journals (Sweden)

    Zhao Tuo

    2015-01-01

    Full Text Available Combining with the situation of soil test site, the large scale experiment was studying about natural foundation, rammed soil-cement piles, CFG pile and gravel pil. A series of conclusions were given from p-s curve, the fitting curve, and the Angle of the stress ratio of pile-soil composite modulus. It has certain guiding significance for the design and construction of pile type, which is used in North China area.

  2. Method of vertically and horizontally cutting steel pipe piles and removing them based on the development of a steel pipe pile vertically cutting machine; Kokanko tatehoko setsudanki no kaihatsu ni yoru kochi chubu no juo setsudan tekkyo koho

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, S.; Takeshita, A.; Kobayashi, K.

    1997-07-25

    A machine for vertically cutting steel pipe piles has newly been developed for the purpose of removing the end portions the shore protection steel pipe piles which interfere with the shield tunneling work in the Ohokagawa River tunneling section on the Minato Mirai 21 Line. This paper reports the development of the machine for vertically cutting steel pipe piles, and a method of cutting the shield tunneling work hindering piles under the ground by using this machine. The obstacle-constituting portions of the piles are removed by destroying the copings, excavating the interior of the piles to make the same hollow so that a cutting machine can be inserted, and cutting the piles vertically and horizontally. The basic structure of the cutting machine comprises a lower cutting unit for making forward and backward and upward and downward movements of a cutter, and an upper movable unit for controlling the rotation of the cutting unit. The cutting of a pile is done by projecting the cutter by a cylinder the base of which is joined to a cutter driver, and then moving the rotating cutter upward. The amounts of movements of these parts are detected by sensors, and an arbitrary range of the underground portion of a pile can be cut by a remote control operation. 10 figs., 1 tab.

  3. Backfilling of a Scour Hole around a Pile in Waves and Current

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Petersen, Thor Ugelvig; Locatelli, Luca

    2013-01-01

    This paper presents the results of an experimental investigation of the backfilling of scour holes around circular piles. Scour holes around a pile are generated either by a current or a wave. Subsequently, the flow climate is changed from current to wave, combined waves and current, or wave...... around the pile for the same wave (or combined waves and current) climate. The time scale of backfilling has been determined as a function of three parameters, namely, (1) the Keulegan-Carpenter number of the initial wave or current (which generates the initial scour hole); (2) that of the subsequent...

  4. INTERACTION OF SOIL-CEMENT PILE SUPPORTING STRUCTURES WITH THE BODY OF A LANDSLIDE

    Directory of Open Access Journals (Sweden)

    D. Y. Ihnatenko

    2017-10-01

    Full Text Available Purpose. Analysis and comparison of the landslide slope finite element model calculation results of the appliance of soil-cement piles, depending on the variation of the retaining structure rigidity, makes it possible to evaluate the effectiveness of their application and the cooperative work of piles with the displacement body. It also makes it possible to make a conclusion about the advantages of using this anti-landslide protection method of the slope. Methodology. Analysis of geomorphological data obtained from the results of laboratory studies of soils on the slope section is considered. Creation of a three-dimensional finite-element slope model according to the constructed sections and depths of the soil layers. Calculation of the nonlinear problem of finite element modeling of the slope with applying of soil-cement piles of various rigidity. Findings. The obtained results of calculating the finite element model of the landslide slope, and the analysis of the stress-strain state of the construction with soil-cement piles has been carried out. Originality. Despite the widespread of using soil-cement piles as enclosing structures for the construction of foundation pits and reinforcement of foundations of emergency structures, special attention should be paid to the study of the expediency of using soil-cement retaining pile structures on landslide areas. Practical value. It is known that soil-cement retaining piles are expediently in use as a protective element, which interacts quite well with the ground environment due to its structure of the initial material. Using of modern computer programs of finite element modeling makes it possible to calculate the efficiency of the use of soil-cement piles and to determine the parameters of the necessary retaining structure according to the given geological structure of the slope, and also, depending on its shape and the physical characteristics of the soils, to compare the performance of different

  5. Assessing the Extent of Sediment Contamination Around Creosote-treated Pilings Through Chemical and Biological Analyses

    Science.gov (United States)

    Stefansson, E. S.

    2008-12-01

    Creosote is a common wood preservative used to treat marine structures, such as docks and bulkheads. Treated dock pilings continually leach polycyclic aromatic hydrocarbons (PAHs) and other creosote compounds into the surrounding water and sediment. Over time, these compounds can accumulate in marine sediments, reaching much greater concentrations than those in seawater. The purpose of this study was to assess the extent of creosote contamination in sediments, at a series of distances from treated pilings. Three pilings were randomly selected from a railroad trestle in Fidalgo Bay, WA and sediment samples were collected at four distances from each: 0 meters, 0.5 meters, 1 meter, and 2 meters. Samples were used to conduct two bioassays: an amphipod bioassay (Rhepoxynius abronius) and a sand dollar embryo bioassay. Grain size and PAH content (using a fluorometric method) were also measured. Five samples in the amphipod bioassay showed significantly lower effective survival than the reference sediment. These consisted of samples closest to the piling at 0 and 0.5 meters. One 0 m sample in the sand dollar embryo bioassay also showed a significantly lower percentage of normal embryos than the reference sediment. Overall, results strongly suggest that creosote-contaminated sediments, particularly those closest to treated pilings, can negatively affect both amphipods and echinoderm embryos. Although chemical data were somewhat ambiguous, 0 m samples had the highest levels of PAHs, which corresponded to the lowest average survival in both bioassays. Relatively high levels of PAHs were found as far as 2 meters away from pilings. Therefore, we cannot say how far chemical contamination can spread from creosote-treated pilings, and at what distance this contamination can still affect marine organisms. These results, as well as future research, are essential to the success of proposed piling removal projects. In addition to creosote-treated pilings, contaminated sediments must

  6. Natural radioactivity at CBPP waste pile

    International Nuclear Information System (INIS)

    Kovac, Jadranka; Marovic, Gordana

    2008-01-01

    Electrical power requirements will necessitate doubling the present generating capacity in Croatia in the future. As a result, environmental discharges associated with the coal power industry will considerably increase. Burning of coal is one source of enhanced radiation exposure to naturally occurring elements, particularly members of uranium and thorium decay chains. By coal burning (in CBPP at about 1700 C degrees) the activity originating from uranium and thorium is redistributed from underground (where the impact on humanity is nil) and liberated into the environment. Most of the radioactive substances are concentrated in the ash and slag, which are heavy and drop to the bottom of a furnace, lately transported to deposit pile, from where some activity may leach into aquifer, or be dispersed by wind. Lighter fly ash, however, is carried up the chimney and into the atmosphere and irradiates people and contaminates food crops. Also, 222 Rn escapes into the atmosphere during incineration, while the non-gaseous members of the uranium decay series remain in the ash and slag. Extensive investigations have been performed in the coal burning power plant (CBPP) Plomin in Croatia and at deposit pile. A network of radon escalation measurements, in-situ gamma-spectrometric measurements and monitoring of waste pile were organized. The results of the measurements confirm that the ash/slag deposite site are well monitored and involve all the necessary protective measures. All obtained data can be used as a valuable database for future estimations and modeling of the impact of radioactive pollution to the marine environment. (author)

  7. In-pile experiments on fuel rod behaviour during a LOCA

    International Nuclear Information System (INIS)

    Sepold, E.H.; Karb, E.H.; Pruessmann, M.

    1981-07-01

    This report describes the results of the Test Series G2/3 within the in-pile experimental program for the investigation of LWR fuel rod behavior. The results were obtained with single rods of a PWR design in the DK loop of the FR2 reactor at the Kernforschungszentrum Karlsruhe (KfK). The in-pile tests with the objective of investigating the influence of a nuclear environment on the mechanisms of fuel rod failure were being performed with irradiated and unirradiated rods. The main parameter of the test program ist the burnup, ranging from 2500 to 35000 MWd/t. The results of test series G2/3 (35000 MWd/t) with respect to the burst data, i.e. burst temperature, burst pressure, and burst strain, do not indicate major differences from the in-pile tests with unirradiated test specimens. (orig.) [de

  8. In-pile experiemts on fuel rod behavior during a LOCA

    International Nuclear Information System (INIS)

    Pruessmann, M.; Karb, E.H.; Sepold, L.

    1981-02-01

    This report describes the results of the Test Series G1 within the in-pile experimental program for the investigation of LWR fuel rod behavior. The results were obtained with single rods of a PWR design in the DK loop of the FR2 reactor at the Kernforschungszentrum Karlsruhe (KfK). The in-pile tests with the objective of investigating the influence of a nuclear environment on the mechansims of fuel rod failure were being performed with irradiated and unirradiated rods. The main parameter of the test program is the burnup ranging from 2500 to 35 000 MWd/t. The results of test series G1 (35 000 MWd/t) with respect to the burst data, i.e. burst temperature, burst pressure, and burst strain, do not indicate major differences from the in-pile tests with unirradiated test specimens. (orig.) [de

  9. Statistical Estimation of Subgrade Reaction Coefficient For Horizontally Loaded Piles

    International Nuclear Information System (INIS)

    Honjo, Yusuke; Zaika, Yulvi; Pokharel, Gyaneswor

    2002-01-01

    Appropriate horizontal subgrade reaction (k h ) is required to evaluate stress and displacement in horizontal loading pile. In order to obtain more accurate prediction of pile behavior, statistical analysis is employed. Based on 21 data set gathered on horizontal loading piles, inverse analysis and regression analysis are carried out. The main value and uncertainty are obtained by inverse analysis, could be employed in the regression analysis. The relationship between the lateral resistant constant (k c ) and SPT N value takes into account in correlated and uncorrelated condition. The results are compared with Port and Harbor Technical Research Institute (JPHA, 1999) and Japan Highway Bridge Specification IV (JRA, 1996). The computed values are found to be very close to the JPHA line and within the range of JRA lines in diameter 0.5 m and 2 m

  10. Multi-shape pulse pile-up correction: The MCPPU code

    International Nuclear Information System (INIS)

    Sabbatucci, Lorenzo; Scot, Viviana; Fernandez, Jorge E.

    2014-01-01

    In spectroscopic measurements with high counting rate, pulse pile-up (PPU) is a common distortion of the spectrum. It is fully ascribable to the pulse handling circuitry of the detector and it is not comprised in the detector response function which is well explained by a purely physical model. Since PPU occurs after the transport inside the detector, this is the first correction to perform in case of spectrum unfolding. Many producers include electronic rejection circuits to limit the appearance of PPU, but it is never suppressed completely. Therefore, it is always necessary to correct PPU distortions after the measurement. In the present work, it is described the post-processing tool MCPPU (Monte Carlo Pulse Pile-Up), based on the MC algorithm developed by Guo et al. (2004, 2005). MCPPU automatically determines the dead time of the counting system and corrects for PPU effects even in the presence of electronic suppression. The capability of allowing a user defined pulse shape makes the code suitable to be used with any kind of detector. The features of MCPPU are illustrated with some examples. - Highlights: • Pulse pile-up (PPU) is a common distortion in radiation detection. • MCPPU is a Monte Carlo code to perform post-processing PPU correction. • MCPPU evaluates automatically the dead time to use in the pile-up recovery. • The measured pulse shape can be introduced as a normalized discrete distribution. • MCPPU is compatible with detectors using electronic rejection circuitry

  11. Static Buckling Model Tests and Elasto-plastic Finite Element Analysis of a Pile in Layers with Various Thicknesses

    Science.gov (United States)

    Okajima, Kenji; Imai, Junichi; Tanaka, Tadatsugu; Iida, Toshiaki

    Damage to piles in the liquefied ground is frequently reported. Buckling by the excess vertical load could be one of the causes of the pile damage, as well as the lateral flow of the ground and the lateral load at the pile head. The buckling mechanism is described as a complicated interaction between the pile deformation by the vertical load and the earth pressure change cased by the pile deformation. In this study, series of static buckling model tests of a pile were carried out in dried sand ground with various thickness of the layer. Finite element analysis was applied to the test results to verify the effectiveness of the elasto-plastic finite element analysis combining the implicit-explicit mixed type dynamic relaxation method with the return mapping method to the pile buckling problems. The test results and the analysis indicated the possibility that the buckling load of a pile decreases greatly where the thickness of the layer increases.

  12. Kinematic Interaction and Rocking Effects on the Seismic Response of Viaducts on Pile Foundations

    International Nuclear Information System (INIS)

    Dezi, F.; Carbonari, S.; Leoni, G.

    2008-01-01

    This paper is aimed at providing a contribution for a more accurate and effective design of bridges founded on piles. A numerical model is employed herein to determine the stresses and displacements in the piles taking into account soil-foundation-structure interaction. A 3D finite element approach is developed for piles and superstructure whereas the soil is assumed to be a Winkler-type medium. The method is applied to single piers representative for a class of bridges. Varying the soil layers characteristics and the pile spacing (from 3 to 5 diameters), bending and axial stresses along piles as well as the pier base shear are computed. A comparison with respect to a fixed-base model is provided. Special issues such as the contribution of the soil profile, of the local amplification and of the rocking at the foundation level are discussed. Soil-structure interaction is found to be essential for effective design of bridges especially for squat piers and soft soil

  13. Dynamic soil-pile-interaction effects on eigenfrequency and damping of slender structures

    DEFF Research Database (Denmark)

    Zania, Varvara

    2014-01-01

    after a rigorous solution of horizontal soil – pile vibration, while the modified SSI eigenperiod and damping are calculated accounting for the cross coupling stiffness and damping terms of the soil – pile system. Disregarding the off diagonal terms is considered inappropriate since it results to non...

  14. Soft Costs Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-05-01

    This fact sheet is an overview of the systems integration subprogram at the U.S. Department of Energy SunShot Initiative. Soft costs can vary significantly as a result of a fragmented energy marketplace. In the U.S., there are 18,000 jurisdictions and 3,000 utilities with different rules and regulations for how to go solar. The same solar equipment may vary widely in its final installation price due to process and market variations across jurisdictions, creating barriers to rapid industry growth. SunShot supports the development of innovative solutions that enable communities to build their local economies and establish clean energy initiatives that meet their needs, while at the same time creating sustainable solar market conditions.

  15. Altering critical depinning current via domain wall pile-up in magnetic nanowires

    International Nuclear Information System (INIS)

    Geng, Liwei D.; Jin, Yongmei M.

    2015-01-01

    An important role of domain wall pile-up in current-driven domain wall depinning in magnetic nanowires is revealed using micromagnetic simulations. It is found that the critical current for domain wall depinning can be substantially reduced and conveniently tuned by controlling domain wall number in the pile-up at pinning site, in analogy to dislocation pile-up responsible for Hall–Petch effect in mechanical strength. Domain wall pinning and depinning at an s-shape bend is considered, and the effects of curvature and current crowding in magnetic circuit on domain wall behaviors are discussed. - Highlights: • Advance fundamental knowledge of current-driven domain wall phenomena. • Provide a novel approach to drastically reduce the critical depinning current. • Solve an outstanding problem of effective control of domain wall pinning/depinning. • Report appealing new findings of magnetic domain wall pile-up mechanism. • Overcome the limitations of materials properties for domain wall-based devices

  16. A simplified computing method of pile group to seismic loads using thin layer element

    International Nuclear Information System (INIS)

    Masao, T.; Hama, I.

    1995-01-01

    In the calculation of pile group, it is said that the results of response by thin layer method give the correct solution with the isotropic and homogeneous soil material in each layer, on the other hand this procedure spends huge computing time. Dynamic stiffness matrix of thin layer method is obtained from inversion of flexibility matrix between pile-i and pile-j. This flexibility matrix is full matrix and its size increase in proportion to the number of piles and thin layers. The greater part of run time is taken into the inversion of flexibility matrix against point loading. We propose the method of decreasing the run time for computing by reducing to banded matrix of flexibility matrix. (author)

  17. Interaction of the Bored Sand and Gravel Drain Pile with the Surrounding Compacted Loam Soil and Foundation Raft Taking into Account Rheological Properties of the Loam Soil and Non-Linear Properties of the Drain Pile

    Science.gov (United States)

    Ter-Martirosyan, Z. G.; Ter-Martirosyan, A. Z.; Anzhelo, G. O.; Buslov, A. S.

    2018-01-01

    The task of the interaction of the sand and gravel drain pile with the surrounding loam soil after its preliminary deep compaction and formation of the composite ground cylinder from the drain pile and surrounding compacted loam soil (cells) is considered in the article. It is seen that the subsidence and carrying capacity of such cell considerably depends on physical and mechanical properties of the compacted drain piles and surrounding loam soil as well as their diameter and intercellular distance. The strain-stress state of the cell is considered not taking into account its component elements, but taking into account linear and elastic-plastic properties of the drain pile and creep flow of the surrounding loam soil. It is stated that depending on these properties the distribution and redistribution of the load on a cell takes place from the foundation raft between the drain pile and surrounding soil. Based on the results of task solving the formulas and charts are given demonstrating the ratio of the load between the drain pile and surrounding loam soil in time.

  18. Statistical fluctuations of the number of neutrons in a pile; Fluctuations statistiques du nombre de neutrons dans une pile

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The theory of the statistical fluctuations in a pile is extended to the space dependent case, and gives the fluctuations of the number of neutrons in a cell of the core or reflector of the pile. This number changes through elementary processes occurring at random, which are, capture, source, fission and scattering. Of all these processes, fission is the only one which changes more than one neutron at a time and so is responsible of the deviation of the fluctuations from a Poisson law. The importance of this deviation depends on the dimensions of the cell compared to the slowing down length. When the dimensions are small, the fluctuations close to a Poisson law. (author) [French] La theorie des fluctuations statistiques est etendue au cas local et donne les fluctuations du nombre de neutrons dans une cellule situee dans le coeur ou le reflecteur de la pile. Ce nombre evolue au cours du temps sous l'influence de phenomenes aleatoires qui sont la capture, la diffusion, les sources et les neutrons secondaires de fission. L'emission simultanee de plusieurs neutrons distingue ce phenomene des precedents qui n'affectent qu'un neutron individuellement. L'importance de ce phenomene sur la loi de fluctuation depend des dimensions de la cellule par rapport a la longueur de ralentissement. Quand ces dimensions sont petites, le caractere particulier de ce phenomene disparait. (auteur)

  19. Analysis of uplift loads of precast-concrete piles in porous soils

    Directory of Open Access Journals (Sweden)

    Stélio Maia Menezes

    2006-01-01

    Full Text Available This paper presents the analysis of uplift load tests in three precast-concrete piles carried out in a collapsible sandy soil. The piles with 12 meters (m length and 0.17 x 0.17 square meter (m2 cross section were instrumented with strain gauges, in order to know the load transfer in depth. Three tests performed in a slow maintained load way were conducted in a natural condition of moisture content soil. A fourth test was carried out after the previous soaking of the soil around the pile head. The tests were performed in the experimental research site at the Universidade Estadual Paulista “Júlio de Mesquita Filho” (Unesp. The results obtained were evaluated by analytical and empirical methods.

  20. Acoustic Emission Signal Processing Technique to Characterize Reactor In-Pile Phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Vivek Agarwal; Magdy Samy Tawfik; James A Smith

    2014-07-01

    Existing and developing advanced sensor technologies and instrumentation will allow non-intrusive in-pile measurement of temperature, extension, and fission gases when coupled with advanced signal processing algorithms. The transmitted measured sensor signals from inside to the outside of containment structure are corrupted by noise and are attenuated, thereby reducing the signal strength and signal-to-noise ratio. Identification and extraction of actual signal (representative of an in-pile phenomenon) is a challenging and complicated process. In this paper, empirical mode decomposition technique is proposed to reconstruct actual sensor signal by partially combining intrinsic mode functions. Reconstructed signal corresponds to phenomena and/or failure modes occurring inside the reactor. In addition, it allows accurate non-intrusive monitoring and trending of in-pile phenomena.

  1. Effect of heterogeneity and anisotropy related to the construction method on transfer processes in waste rock piles.

    Science.gov (United States)

    Lahmira, Belkacem; Lefebvre, René; Aubertin, Michel; Bussière, Bruno

    2016-01-01

    Waste rock piles producing acid mine drainage (AMD) are partially saturated systems involving multiphase (gas and liquid) flow and coupled transfer processes. Their internal structure and heterogeneous properties are inherited from their wide-ranging material grain sizes, their modes of deposition, and the underlying topography. This paper aims at assessing the effect of physical heterogeneity and anisotropy of waste rock piles on the physical processes involved in the generation of AMD. Generic waste rock pile conditions were represented with the numerical simulator TOUGH AMD based on those found at the Doyon mine waste rock pile (Canada). Models included four randomly distributed material types (coarse, intermediate, fine and very fine-grained). The term "randomly" as used in this study means that the vertical profile and spatial distribution of materials in waste rock piles (internal structure) defy stratigraphy principles applicable to natural sediments (superposition and continuity). The materials have different permeability and capillary properties, covering the typical range of materials found in waste rock piles. Anisotropy with a larger horizontal than vertical permeability was used to represent the effect of pile construction by benches, while the construction by end-dumping was presumed to induce a higher vertical than horizontal permeability. Results show that infiltrated precipitation preferentially flows in fine-grained materials, which remain almost saturated, whereas gas flows preferentially through the most permeable coarse materials, which have higher volumetric gas saturation. Anisotropy, which depends on pile construction methods, often controls global gas flow paths. Construction by benches favours lateral air entry close to the pile slope, whereas end-dumping leads to air entry from the surface to the interior of the pile by secondary gas convection cells. These results can be useful to construct and rehabilitate waste rock piles to minimize

  2. Estimate of the residual loads obtained in the end of piles driven in porous soils

    Directory of Open Access Journals (Sweden)

    David de Carvalho

    2005-02-01

    Full Text Available In the geotechnical engineering the study about the quantification of the residual loads in the pile end, after the end of the first loading of the load test attempt, highlighted some works on its interpretation in the curve load versus pile settlement. The construction of a mathematical model to study such a phenomenon is based on the Relations of Cambefort Precast-concrete piles were specially built for this research. They have special elements installed all along their length where the residual loads inlaid in the pile end region could be measured by means of deformation strain gauges.

  3. Strain measurements by fiber Bragg grating sensors for in situ pile loading tests

    Science.gov (United States)

    Schmidt-Hattenberger, Cornelia; Straub, Tilmann; Naumann, Marcel; Borm, Günter; Lauerer, Robert; Beck, Christoph; Schwarz, Wolfgang

    2003-07-01

    A fiber Bragg grating (FBG) sensor network has been installed into a large diameter concrete pile on a real construction site. The intention was to monitor its deformation behavior during several quasi-static loading cycles. The skin friction between pile and subsoil affecting the ultimate bearing capacity of the pile as well as the settlement behavior of the structure under investigation has been derived from our measurements. A comparison between the results of the fiber Bragg grating sensors and conventional concrete strain gages (CSG) has shown excellent correspondence.

  4. ESTIMATION OF AGING EFFECTS OF PILES IN MALAYSIAN OFFSHORE LOCATIONS

    Directory of Open Access Journals (Sweden)

    JERIN M. GEORGE

    2017-04-01

    Full Text Available An increasing demand for extending life and subsequently higher loading requirements of offshore jacket platforms are among the key problems faced by the offshore industry. The Aging effect has been proved to increase the axial capacity of piles, but proper methods to estimate and quantify these effects have not been developed. Borehole data from ten different Malaysian offshore locations have been analysed and they were employed to estimate the setup factor for different locations using AAU method. The setup factors found were used in the Skov and Denver equation to calculate capacity ratios of the offshore piles. The study showed that there will be an average improvement in the axial capacity of offshore piles by 42.2% and 34.9% for clayey and mixed soils respectively after a time equal to the normal design life (25 years of a jacket platform.

  5. Response of stiff piles to random two-way lateral loading

    DEFF Research Database (Denmark)

    Bakmar, Christian LeBlanc; Byrne, B.W.; Houlsby, G. T.

    2010-01-01

    A model for predicting the accumulated rotation of stiff piles under random two-way loading is presented. The model is based on a strain superposition rule similar to Miner's rule and uses rainflow-counting to decompose a random time-series of varying loads into a set of simple load reversals. Th....... The method is consistent with the work of LeBlanc et al. (2010) and is supported by 1g laboratory tests. An example is given for an offshore wind turbine indicating that accumulated pile rotation during the life of the turbine is dominated by the worst expected load.......A model for predicting the accumulated rotation of stiff piles under random two-way loading is presented. The model is based on a strain superposition rule similar to Miner's rule and uses rainflow-counting to decompose a random time-series of varying loads into a set of simple load reversals...

  6. Piloting procedure for a pile running below critical level

    International Nuclear Information System (INIS)

    Lacour, J.; Raievski, V.

    1957-01-01

    The knowledge of the subcritical state of a reactor in the course of starting up makes it possible to avoid passing too quickly through the critical state. The problem arises every time the pile is put into action again following, for example, an appreciable modification in the fuel charge, or an accidental fall of the security rods during a run at high flux or at high temperature. The method described provides a mean of knowing at each moment the anti-reactivity value of the pile by means of a direct-reading instrument mounted on the control board. This result is obtained by superimposing a fixed frequency oscillation on the normal movement of a control rod, and reading on a phase-meter the dephasing of the neutron density. Theory shows, and experiments confirm, that for a given frequency the dephasing depends only on the lifetime of the fast neutrons, the characteristics of the slow neutrons and the anti-reactivity of the pile. The minimum time necessary for an anti-reactivity determination is equal to a modulation period (from 1 to 4 seconds). (authors) [fr

  7. International dosimetry experiment on the zero power pile of the Boris Kidric Institute at Vinca (Yugoslavia) (1961); Experience internationale de dosimetrie sur la pile de puissance nulle de l'Institut Boris Kidric de Vinca (Yougoslavie) (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Weill, J; Furet, J; Baillet, J; Donvez, G; Duchene, J; Gras, R; Mercier, R [Commissariat a l' Energie Atomique, Section Autonome d' Electronique des Reacteurs, Saclay (France). Centre d' Etudes Nucleaires; Chenouard, J; Lecomte, J [Commissariat a l' Energie Atomique, Dept. de Physico - Chimie, Service des Isotopes Stables, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    On the occasion of the international dosimetry experiment on the zero power pile of the Yugoslavian Atomic Energy Centre at Vinca, the Commissariat a l'energie Atomique had agreed to prepare the measurement and security equipment and see to the manipulation of the heavy water, and in addition was responsible for the operation and the starting up of the pile during the experiment. The measurement and security apparatus, developed at Saclay and installed on the pile for low and high pressure runs, is listed, together with the safety equipment added near the control room. The various operations and manipulations carried out on the pile are described: filling with heavy water, starting up, determination of the critical level, testing the efficiency of the rods, operating the pile during the experiments. By operating to a carefully planned schedule, the experiments were, finished before the date fixed by the International Atomic Agency. (authors) [French] Dans le cadre de l'experience internationale de dosimetrie sur la pile de puissance nulle du Centre d'Etudes Nucleaires Yougoslave de Vinca, le Commissariat a l'Energie Atomique avait accepte de preparer l'equipement de controle et de securite, de pourvoir a la manipulation de l'eau lourde de la pile et avait la responsabilite de son fonctionnement et de sa mise en marche pendant l'experience. On enumere ici l'appareillage de controle et de securite installe sur la pile pour les marches a basse et haute puissances, appareillage mis au point a Saclay, ainsi que les protections ajoutees a proximite de la salle de controle. On decrit les differentes manipulations et operations effectuees sur la pile: remplissage d'eau lourde, demarrage, recherche du niveau critique, verification de l'efficacite des barres, conduite de la pile pendant les experiences. Grace a un planning tres serre qui a pu etre tenu, les experiences ont pu etre terminees avant la date prevue par l'Agence Atomique Internationale. (auteurs)

  8. Numerical modeling of Thermal Response Tests in Energy Piles

    Science.gov (United States)

    Franco, A.; Toledo, M.; Moffat, R.; Herrera, P. A.

    2013-05-01

    Nowadays, thermal response tests (TRT) are used as the main tools for the evaluation of low enthalpy geothermal systems such as heat exchangers. The results of TRT are used for estimating thermal conductivity and thermal resistance values of those systems. We present results of synthetic TRT simulations that model the behavior observed in an experimental energy pile system, which was installed at the new building of the Faculty of Engineering of Universidad de Chile. Moreover, we also present a parametric study to identify the most influent parameters in the performance of this type of tests. The modeling was developed using the finite element software COMSOL Multiphysics, which allows the incorporation of flow and heat transport processes. The modeled system consists on a concrete pile with 1 m diameter and 28 m deep, which contains a 28 mm diameter PEX pipe arranged in a closed circuit. Three configurations were analyzed: a U pipe, a triple U and a helicoid shape implemented at the experimental site. All simulations were run considering transient response in a three-dimensional domain. The simulation results provided the temperature distribution on the pile for a set of different geometry and physical properties of the materials. These results were compared with analytical solutions which are commonly used to interpret TRT data. This analysis demonstrated that there are several parameters that affect the system response in a synthetic TRT. For example, the diameter of the simulated pile affects the estimated effective thermal conductivity of the system. Moreover, the simulation results show that the estimated thermal conductivity for a 1 m diameter pile did not stabilize even after 100 hours since the beginning of the test, when it reached a value 30% below value used to set up the material properties in the simulation. Furthermore, we observed different behaviors depending on the thermal properties of concrete and soil. According to the simulations, the thermal

  9. Avoidance of wind farms by harbour seals is limited to pile driving activities.

    Science.gov (United States)

    Russell, Debbie J F; Hastie, Gordon D; Thompson, David; Janik, Vincent M; Hammond, Philip S; Scott-Hayward, Lindesay A S; Matthiopoulos, Jason; Jones, Esther L; McConnell, Bernie J

    2016-12-01

    As part of global efforts to reduce dependence on carbon-based energy sources there has been a rapid increase in the installation of renewable energy devices. The installation and operation of these devices can result in conflicts with wildlife. In the marine environment, mammals may avoid wind farms that are under construction or operating. Such avoidance may lead to more time spent travelling or displacement from key habitats. A paucity of data on at-sea movements of marine mammals around wind farms limits our understanding of the nature of their potential impacts.Here, we present the results of a telemetry study on harbour seals Phoca vitulina in The Wash, south-east England, an area where wind farms are being constructed using impact pile driving. We investigated whether seals avoid wind farms during operation, construction in its entirety, or during piling activity. The study was carried out using historical telemetry data collected prior to any wind farm development and telemetry data collected in 2012 during the construction of one wind farm and the operation of another.Within an operational wind farm, there was a close-to-significant increase in seal usage compared to prior to wind farm development. However, the wind farm was at the edge of a large area of increased usage, so the presence of the wind farm was unlikely to be the cause.There was no significant displacement during construction as a whole. However, during piling, seal usage (abundance) was significantly reduced up to 25 km from the piling activity; within 25 km of the centre of the wind farm, there was a 19 to 83% (95% confidence intervals) decrease in usage compared to during breaks in piling, equating to a mean estimated displacement of 440 individuals. This amounts to significant displacement starting from predicted received levels of between 166 and 178 dB re 1 μPa (p-p) . Displacement was limited to piling activity; within 2 h of cessation of pile driving, seals were distributed as

  10. The Ultimate Pile Bearing Capacity from Conventional and Spectral Analysis of Surface Wave (SASW) Measurements

    Science.gov (United States)

    Faizah Bawadi, Nor; Anuar, Shamilah; Rahim, Mustaqqim A.; Mansor, A. Faizal

    2018-03-01

    A conventional and seismic method for determining the ultimate pile bearing capacity was proposed and compared. The Spectral Analysis of Surface Wave (SASW) method is one of the non-destructive seismic techniques that do not require drilling and sampling of soils, was used in the determination of shear wave velocity (Vs) and damping (D) profile of soil. The soil strength was found to be directly proportional to the Vs and its value has been successfully applied to obtain shallow bearing capacity empirically. A method is proposed in this study to determine the pile bearing capacity using Vs and D measurements for the design of pile and also as an alternative method to verify the bearing capacity from the other conventional methods of evaluation. The objectives of this study are to determine Vs and D profile through frequency response data from SASW measurements and to compare pile bearing capacities obtained from the method carried out and conventional methods. All SASW test arrays were conducted near the borehole and location of conventional pile load tests. In obtaining skin and end bearing pile resistance, the Hardin and Drnevich equation has been used with reference strains obtained from the method proposed by Abbiss. Back analysis results of pile bearing capacities from SASW were found to be 18981 kN and 4947 kN compared to 18014 kN and 4633 kN of IPLT with differences of 5% and 6% for Damansara and Kuala Lumpur test sites, respectively. The results of this study indicate that the seismic method proposed in this study has the potential to be used in estimating the pile bearing capacity.

  11. Dislocation pile-ups, slip-bands, ellipsoids, and cracks

    International Nuclear Information System (INIS)

    Brown, Lawrence M.

    2005-01-01

    The classic theories of dislocation pile-ups, initiated by Eshelby, Frank and Nabarro, and by Leibfried, can be greatly simplified if it is recognised that the dislocations in the pile-up will experience uniform stress if they are lodged in an ellipsoidal interface. Elementary algebra then produces the familiar results from continuum theory. It seems possible that the ellipsoid construction may represent physical reality if it is taken to represent a three-dimensional slip-band. If so, there are concentrated forces spreading the band perpendicular to the slip band as well as parallel to it. Such ellipsoids also represent Mode II and Mode III cracks, and give a method for dealing with the more complicated Mode I cracks

  12. The characterization of Vicker's microhardness indentations and pile-up profiles as a strain-hardening microprobe

    International Nuclear Information System (INIS)

    Santos, C. Jr.

    1998-04-01

    Microhardness measurements have long been used to examine strength properties and changes in strength properties in metals, for example, as induced by irradiation. Microhardness affords a relatively simple test that can be applied to very small volumes of material. Microhardness is nominally related to the flow stress of the material at a fixed level of plastic strain. Further, the geometry of the pile-up of material around the indentation is related to the strain-hardening behavior of a material; steeper pile-ups correspond to smaller strain-hardening rates. In this study the relationship between pile-up profiles and strain hardening is examined using both experimental and analytical methods. Vickers microhardness tests have been performed on a variety of metal alloys including low alloy, high Cr and austenitic stainless steels. The pile-up topology around the indentations has been quantified using confocal microscopy techniques. In addition, the indentation and pile-up geometry has been simulated using finite element method techniques. These results have been used to develop an improved quantification of the relationship between the pile-up geometry and the strain-hardening constitutive behavior of the test material

  13. Fiber Bragg Grating-Based Performance Monitoring of Piles Fiber in a Geotechnical Centrifugal Model Test

    Directory of Open Access Journals (Sweden)

    Xiaolin Weng

    2014-01-01

    Full Text Available In centrifugal tests, conventional sensors can hardly capture the performance of reinforcement in small-scale models. However, recent advances in fiber optic sensing technologies enable the accurate and reliable monitoring of strain and temperature in laboratory geotechnical tests. This paper outlines a centrifugal model test, performed using a 60 g ton geocentrifuge, to investigate the performance of pipe piles used to reinforce the loess foundation below a widened embankment. Prior to the test, quasidistributed fiber Bragg grating (FBG strain sensors were attached to the surface of the pipe piles to measure the lateral friction resistance in real time. Via the centrifuge actuator, the driving of pipe piles was simulated. During testing, the variations of skin friction distribution along the pipe piles were measured automatically using an optical fiber interrogator. This paper represents the presentation and detailed analysis of monitoring results. Herein, we verify the reliability of the fiber optic sensors in monitoring the model piles without affecting the integrity of the centrifugal model. This paper, furthermore, shows that lateral friction resistance developed in stages with the pipe piles being pressed in and that this sometimes may become negative.

  14. Greenhouse gas emissions during composting of dairy manure: Delaying pile mixing does not reduce overall emissions

    Science.gov (United States)

    The effect of the timing of pile mixing on greenhouse gas (GHG) emissions during dairy manure composting was determined using large flux chambers designed to completely cover replicate pilot-scale compost piles. GHG emissions from compost piles that were mixed at 2, 3, 4, or 5 weeks after initial c...

  15. Effect of relative pile’s stiffness on lateral pile response under loading of large eccentricity

    DEFF Research Database (Denmark)

    Zania, Varvara; Hededal, Ole; Klinkvort, R.T.

    2015-01-01

    The wide application of monopiles as foundations for offshore wind turbines has raised the issue of the suitability of the p –y curves proposed by API for lateral pile loading, since the latter were developed after full-scale tests on flexible and slender piles. This study investigates the role...... of the relative pile’s stiffness, when it is subjected to lateral load of large eccentricity. Employing centrifuge experiments, a hollow steel pile well instrumented with strain gauge pairs has been subjected to lateral load. The bending moment distribution of the model pile embedded in uniform, dense, dry sand...... was obtained under two different stress levels and two different embedment depths. Hence, the p – y curves were obtained providing an insight into the effect of the relative pile’s stiffness on the soil – pile interaction, while the effect of the installation process could also be evaluated....

  16. Numerical investigation on the thermo-mechanical behavior of a quadratic cross section pile heat exchanger

    DEFF Research Database (Denmark)

    Alberdi Pagola, Maria; Madsen, Søren; Lund Jensen, Rasmus

    2017-01-01

    Pile heat exchangers are traditional foundation piles with built in heat exchangers. As such, the footing of the building both serves as a structural component and a heating/cooling supply element. The existing geotechnical design standards do not consider the nature of thermo-active foundations...... and, therefore, there is a need to develop guidelines to design them properly. This paper contributes by studying the thermo-mechanical behavior of the precast piles which are 15-meter long and have a quadratic cross section and a W-shape pipe heat exchanger. This article aims to numerically assess...... the additional changes in the pile load transfer generated by its heating and cooling. In addressing this objective, a preliminary multi-physical finite element analysis is conducted which serves as a tool for exploring: i) the thermally induced mechanical stresses within the concrete and on the pile-soil axial...

  17. The formation of technic soil in a revegetated uranium ore waste rock pile (Limousin, France)

    Science.gov (United States)

    Boekhout, Flora; Gérard, Martine; Kanzari, Aisha; Calas, Georges; Descostes, Michael

    2014-05-01

    Mining took place in France between 1945 and 2001 during which time ~210 different sites were exploited and/or explored. A total of 76 Kt of uranium was produced, 52 Mt of ore was extracted, but also 200 Mt of waste rocks was produced, the majority of which, with uranium levels corresponding to the natural environment. So far, the processes of arenisation and technic soil formation in waste rock piles are not well understood but have important implications for understanding the environmental impact and long-term speciation of uranium. Understanding weathering processes in waste rock piles is essential to determine their environmental impact. The main objectives of this work are to assess 1) the micromorphological features and neo-formed U-bearing phases related to weathering and 2) the processes behind arenisation of the rock pile. The site that was chosen is the Vieilles Sagnes waste rock pile in Fanay (Massif Central France) that represents more or less hydrothermally altered granitic rocks that have been exposed to weathering since the construction of the waste rock pile approximately 50 years ago. Two trenches were excavated to investigate the vertical differentiation of the rock pile. This site serves as a key location for studying weathering processes of waste rock piles, as it has not been reworked after initial construction and has therefore preserved information on the original mineralogy of the waste rock pile enabling us to access post emplacement weathering processes. The site is currently overgrown by moss, meter high ferns and small trees. At present day the rock pile material can be described as hydrothermally altered rocks and rock fragments within a fine-grained silty clay matrix exposed to surface conditions and weathering. A sandy "paleo" technic soil underlies the waste rock pile and functions as a natural liner by adsorption of uranium on clay minerals. Post-mining weathering of rock-pile material is superimposed on pre-mining hydrothermal and

  18. Axial compressive bearing capacity of piles in oil-contaminated sandy soil using FCV

    NARCIS (Netherlands)

    Mohammadi, Amirhossein; Ebadi, Taghi; Eslami, Abolfazl; Zee, van der S.E.A.T.M.

    2018-01-01

    Oil and its derivatives contaminate many soils and not only affect their chemical and biological properties but also their geotechnical properties. As oil contamination may deteriorate the functioning of piles, this paper addresses the effects of oil contamination on soil–pile interactions. Axial

  19. NEET In-Pile Ultrasonic Sensor Enablement-Final Report

    Energy Technology Data Exchange (ETDEWEB)

    J. Daw; J. Rempe; J. Palmer; P. Ramuhalli; R. Montgomery; H.T. Chien; B. Tittmann; B. Reinhardt; P. Keller

    2014-09-01

    Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which is a collaborative effort between the Idaho National Laboratory, the Pacific Northwest National Laboratory, the Argonne National Laboratory, and the Pennsylvania State University. The objective of this report is to document the objectives and accomplishments from this three year project. As summarized within this document, significant work has been accomplished during this three year project.

  20. Reheating experiment in the 35-ton pile

    International Nuclear Information System (INIS)

    Cherot, J.; Girard, Y.

    1957-01-01

    When the 35-ton pile was started up it was necessary for us, in order to study certain effects (xenon for example), to know the anti reactivity value of the rods as a function of their dimensions. We have made use of the possibility, in the reheating experiment, of raising the temperature of the graphite-uranium block by simple heating, in order to determine the anti reactivity curves of the rods, and from that the overall temperature coefficient. For the latter we have considered two solutions: first, one in which the average temperature of the pile is defined as our arithmetical mean of the different values given by the 28 thermocouples distributed throughout the pile; a second in which the temperature in likened to a poisoning and is balanced by the square of the flux. The way in which the measurements have been made is indicated, and the different instruments used are described. The method of reheating does not permit the separation of the temperature coefficients of uranium and of graphite. The precision obtained is only moderate, and suffers from the changes of various parameters necessary to other manipulations carried out simultaneously (life time modulators for example), and finally it is a function of the comparatively restricted time allowed. It is evident of course that more careful stabilisation at the different plateaux chosen would have necessitated long periods of reheating. (author) [fr

  1. Occupational PAH Exposures during Prescribed Pile Burns

    Science.gov (United States)

    Robinson, M. S.; Anthony, T. R.; Littau, S. R.; Herckes, P.; Nelson, X.; Poplin, G. S.; Burgess, J. L.

    2008-01-01

    Wildland firefighters are exposed to particulate matter and gases containing polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens. Our objective was to evaluate the extent of firefighter exposure to particulate and PAHs during prescribed pile burns of mainly ponderosa pine slash and determine whether these exposures were correlated with changes in urinary 1-hydroxypyrene (1-HP), a PAH metabolite. Personal and area sampling for particulate and PAH exposures were conducted on the White Mountain Apache Tribe reservation, working with 21 Bureau of Indian Affairs/Fort Apache Agency wildland firefighters during the fall of 2006. Urine samples were collected pre- and post-exposure and pulmonary function was measured. Personal PAH exposures were detectable for only 3 of 16 PAHs analyzed: naphthalene, phenanthrene, and fluorene, all of which were identified only in vapor-phase samples. Condensed-phase PAHs were detected in PM2.5 area samples (20 of 21 PAHs analyzed were detected, all but naphthalene) at concentrations below 1 μg m−3. The total PAH/PM2.5 mass fractions were roughly a factor of two higher during smoldering (1.06 ± 0.15) than ignition (0.55 ± 0.04 μg mg−1). There were no significant changes in urinary 1-HP or pulmonary function following exposure to pile burning. In summary, PAH exposures were low in pile burns, and urinary testing for a PAH metabolite failed to show a significant difference between baseline and post-exposure measurements. PMID:18515848

  2. Performance of pile supported sign structures : [brief].

    Science.gov (United States)

    2015-05-01

    Sign structures in Wisconsin are typically supported by drilled shaft foundations or spread : footing foundations. However, when the soil conditions are not suitable to be supported on : drilled shafts or spread footings, a group of piles could suppo...

  3. Protection for work in the pressure tank of the pile G2; Protection des travaux dans le caisson de la pile G2

    Energy Technology Data Exchange (ETDEWEB)

    Chassany, J Ph; Rodier, J [Commissariat a l' Energie Atomique, Service de Protection contre les Radiations, Marcoule (France). Centre d' Etudes Nucleaires

    1961-07-01

    While the pile was shut down after a three-month run at full power, the secondary circuit was cleaned and some alterations were carried out. The pile contained 100 tons of uranium, half of which made up the periphery and was irradiated uranium. The possibility of carrying on work inside the pressure tank was not considered at the time of construction. Because of the heat and the irradiation it was only possible to remain in the pressure tank for a limited period of time, and several operators received doses of the order of 1.5 rem. Cotton clothing gave satisfactory protection against contamination and was more comfortable than the vinyl equipment. The work lasted for 17 days and involved 881 incursions into the pressure tank. (author) [French] Un nettoyage et des modifications ont ete realises dans le circuit secondaire pendant l'arret de la pile apres un fonctionnement de trois mois a pleine puissance. La pile contenait 100 tonnes d'uranium dont la moitie, composant la peripherie, etait de l'uranium irradie. La possibilite d'entreprendre un travail a l'interieur du caisson n'avait pas ete envisage lors de la construction. Le temps de sejour dans le caisson etait a la fois limite par l'irradiation et la chaleur, plusieurs operateurs, ont integre une dose de l'ordre de 1,5 rem. Les vetements de coton ont apporte une protection contre la contamination satisfaisante et un confort relatif par rapport aux equipements de vinyle. L'intervention a dure 17 jours, a comporte 881 entrees dans le caisson. (auteur)

  4. Remote-welding technique for assembling in-pile IASCC capsule in hot cell

    International Nuclear Information System (INIS)

    Kawamata, Kazuo; Ishii, Toshimitsu; Kanazawa, Yoshiharu; Iwamatsu, Shigemi; Ohmi, Masao; Shimizu, Michio; Matsui, Yoshinori; Saito, Jun-ichi; Ugachi, Hirokazu; Kaji, Yoshiyuki; Tsukada, Takashi

    2006-01-01

    In order to investigate behavior of the irradiation assisted stress corrosion cracking (IASCC) caused by the simultaneous effects of neutron irradiation and high temperature water environment in such a light water reactor (LWR), it is necessary to perform crack growth tests in an in-pile IASCC capsule irradiated in the Japan Materials Testing Reactor (JMTR). The development of the remote-welding technique is essential for remotely assembling the in-pile IASCC capsule installing the pre-irradiated CT specimens. This report describes a new remote-welding machine developed for assembling the in-pile IASCC capsule. The remote-welding technique that the capsule tube is rotated light under the fixed torch was applied to the machine for the welding of thick and large-diameter tubes. The assembly work of four in-pile IASCC capsules having pre-irradiated CT specimens in the hot cell was succeeded for performing the crack growth test under the neutron irradiation in JMTR. The irradiation test of two capsules has been already finished in JMTR without problems. (author)

  5. Characterization of Odorant Compounds from Mechanical Aerated Pile Composting and Static Aerated Pile Composting.

    Science.gov (United States)

    Kumari, Priyanka; Lee, Joonhee; Choi, Hong-Lim

    2016-04-01

    We studied airborne contaminants (airborne particulates and odorous compounds) emitted from compost facilities in South Korea. There are primarily two different types of composting systems operating in Korean farms, namely mechanical aerated pile composting (MAPC) and aerated static pile composting (SAPC). In this study, we analyzed various particulate matters (PM10, PM7, PM2.5, PM1, and total suspended particles), volatile organic compounds and ammonia, and correlated these airborne contaminants with microclimatic parameters, i.e., temperature and relative humidity. Most of the analyzed airborne particulates (PM7, PM2.5, and PM1) were detected in high concentration at SAPC facilities compered to MAPC; however these differences were statistically non-significant. Similarly, most of the odorants did not vary significantly between MAPC and SAPC facilities, except for dimethyl sulfide (DMS) and skatole. DMS concentrations were significantly higher in MAPC facilities, whereas skatole concentrations were significantly higher in SAPC facilities. The microclimate variables also did not vary significantly between MAPC and SAPC facilities, and did not correlate significantly with most of the airborne particles and odorous compounds, suggesting that microclimate variables did not influence their emission from compost facilities. These findings provide insight into the airborne contaminants that are emitted from compost facilities and the two different types of composting agitation systems.

  6. Geology and hydrology in the vicinity of the inactive uranium mill tailings pile, Ambrosia Lake, New Mexico

    International Nuclear Information System (INIS)

    Purtymun, W.D.; Wienke, C.L.; Dreesen, D.R.

    1977-06-01

    A study was made of the geology and hydrology of the immediate area around a uranium mill at Ambrosia Lake, New Mexico. The mill was in operation from June 1958 through April 1963 and produced 2.7 x 10 9 kg of tailings. The possible environmental consequences of this inactive tailings pile must first be delineated so that stabilization needs and future stabilization success can be properly assessed. The Ambrosia Lake area is underlain by over 1000 m of alternating shales, siltstones, and sandstones that dip gently to the northeast into the San Juan Basin. Water-bearing sandstones make up less than 25 percent of this sedimentary section. Water quality in the sandstones is fair to poor, with total dissolved solids ranging from 500 to 2000 mg/l. The present total volume of tailings is estimated at 1.5 x 10 6 m 3 and ranges in thickness from about 1 to 10 m. The tailings pile is underlain by the Mancos shale which dips to the northeast. The shale is about 120 m thick with three interbedded silty sandstones that are about 9 m in thickness. One of these sandstones outcrops beneath the western part of the pile; the eastern part of the pile is underlain by shale. Ground water in the shales and sandstones beneath the pile is recharged by runoff north of the pile and from three ponds located north, northeast, and east of the pile. The movement of water in shale and sandstones is to the southwest. Secondary recharge to the water in the shales and sandstone is from the basin within the tailings pile. Water in the southeast part of the tailings basin is forming a ground water mound above the underlying sediments. The major transport mechanisms of tailings and possible contaminants from the pile include wind erosion, surface water runoff, movement of ground water beneath the pile, and gaseous diffusion from the pile

  7. Thermal integrity profiling for augered cast-in-place piles – implementation plan : summary.

    Science.gov (United States)

    2017-09-01

    Auger-cast-in-place (ACIP) piles are created when an auger the diameter and length of the desired pile is drilled into the ground. Concrete is pumped through the central axis of the auger as it is withdrawn, pulling up excavated soil as concrete fill...

  8. Experimental evaluation of the dynamic characteristics of a massive pile foundation

    International Nuclear Information System (INIS)

    Guelkan, P.; Erdik, M.

    1985-01-01

    Forced vibration tests on a 23 m square, 3 m thick pile foundation are described. Utilizing the recorded horizontal acceleration of the pile cap as a function of the driving frequency, the effective stiffness and damping of the systems were calculated, and these were compared with the theoretically determined values. The agreement between theory and experiment was rather poor for the frequencies at which the tests were conducted. (orig.)

  9. Critical sizes and flux distributions in the shut down pile; Tailles critiques et cartes de flux a froid

    Energy Technology Data Exchange (ETDEWEB)

    Banchereau, A; Berthier, P; Genthon, J P; Gourdon, C; Lattes, R; Martelly, J; Mazancourt, R de; Portes, L; Sagot, M; Schmitt, A P; Tanguy, P; Teste du Bailler, A; Veyssiere, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    An important part of the experiments carried out on the reactor G1 during a period of shut-down has consisted in determinations of critical sizes, and measurements of flux distribution by irradiations of detectors. This report deals with the following points: 1- Critical sizes of the flat pile, the long pile and the uranium-thorium pile. 2- Flux charts of the same piles, and study of an exponential experiment. 3- Determination of the slit effect. 4- Calculation of the anisotropy of the lattice. 5- Description of the experimental apparatus of the irradiation measurements. (author) [French] Une part importante des experiences a froid effectuees sur le reacteur G1 a consiste en des determinations de tailles critiques et des mesures de distributions de flux par irradiations de detecteurs. Le present rapport traite les points suivants: 1- Tailles critiques de la pile plate, de la pile longue, de la pile a uranium-thorium. 2 - Cartes de flux des memes piles et etude d'une experience exponentielle. 3 - Determination de l'effet de fente. 4 - Calcul de l'anisotropie du reseau. 5 - Description de l'appareillage experimental des mesures d'irradiations. (auteur)

  10. Critical sizes and flux distributions in the shut down pile; Tailles critiques et cartes de flux a froid

    Energy Technology Data Exchange (ETDEWEB)

    Banchereau, A.; Berthier, P.; Genthon, J.P.; Gourdon, C.; Lattes, R.; Martelly, J.; Mazancourt, R. de; Portes, L.; Sagot, M.; Schmitt, A.P.; Tanguy, P.; Teste du Bailler, A.; Veyssiere, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    An important part of the experiments carried out on the reactor G1 during a period of shut-down has consisted in determinations of critical sizes, and measurements of flux distribution by irradiations of detectors. This report deals with the following points: 1- Critical sizes of the flat pile, the long pile and the uranium-thorium pile. 2- Flux charts of the same piles, and study of an exponential experiment. 3- Determination of the slit effect. 4- Calculation of the anisotropy of the lattice. 5- Description of the experimental apparatus of the irradiation measurements. (author) [French] Une part importante des experiences a froid effectuees sur le reacteur G1 a consiste en des determinations de tailles critiques et des mesures de distributions de flux par irradiations de detecteurs. Le present rapport traite les points suivants: 1- Tailles critiques de la pile plate, de la pile longue, de la pile a uranium-thorium. 2 - Cartes de flux des memes piles et etude d'une experience exponentielle. 3 - Determination de l'effet de fente. 4 - Calcul de l'anisotropie du reseau. 5 - Description de l'appareillage experimental des mesures d'irradiations. (auteur)

  11. Asymptotic expressions for the nearest and furthest dislocations in a pile-up against a grain boundary

    KAUST Repository

    Hall, Cameron L.

    2010-10-14

    In 1965, Armstrong and Head explored the problem of a pile-up of screw dislocations against a grain boundary. They used numerical methods to determine the positions of the dislocations in the pile-up and they were able to fit approximate formulae for the locations of the first and last dislocations. These formulae were used to gain insights into the Hall-Petch relationship. More recently, Voskoboinikov et al. used asymptotic techniques to study the equivalent problem of a pile-up of a large number of screw dislocations against a bimetallic interface. In this paper, we extend the work of Voskoboinikov et al. to construct systematic asymptotic expressions for the formulae proposed by Armstrong and Head. The further extension of these techniques to more general pile-ups is also outlined. As a result of this work, we show that a pile-up against a grain boundary can become equivalent to a pile-up against a locked dislocation in the case where the mismatch across the boundary is small. © 2010 Taylor & Francis.

  12. Asymptotic expressions for the nearest and furthest dislocations in a pile-up against a grain boundary

    KAUST Repository

    Hall, Cameron L.

    2010-01-01

    In 1965, Armstrong and Head explored the problem of a pile-up of screw dislocations against a grain boundary. They used numerical methods to determine the positions of the dislocations in the pile-up and they were able to fit approximate formulae for the locations of the first and last dislocations. These formulae were used to gain insights into the Hall-Petch relationship. More recently, Voskoboinikov et al. used asymptotic techniques to study the equivalent problem of a pile-up of a large number of screw dislocations against a bimetallic interface. In this paper, we extend the work of Voskoboinikov et al. to construct systematic asymptotic expressions for the formulae proposed by Armstrong and Head. The further extension of these techniques to more general pile-ups is also outlined. As a result of this work, we show that a pile-up against a grain boundary can become equivalent to a pile-up against a locked dislocation in the case where the mismatch across the boundary is small. © 2010 Taylor & Francis.

  13. The transformation of weak saturated soils using piles-drains for improving its mechanical properties

    Science.gov (United States)

    Ter-Martirosyan, Z. G.; Ter-Martirosyan, A. Z.; Sidorov, V. V.

    2018-04-01

    In practice of increased responsibility structures design there are often weak saturated clayey soils with low characteristics of deformability and strength take place on the construction site. In these cases, foundations using piles-drains of sandy or coarse material are recommended by norms, which is able to bear the load and to accelerate the consolidation process. The presented solutions include an analytical solution of the interaction problem between piles and slab raft foundation with the surrounding soil of the base with the possibility of extension of pile shaft. The closed-form solutions to determine the stresses in pile shaft and in the soil under the foundation slab are obtained. The article presents the results of large scale tests in the pilot area construction of major energy facilities in Russia.

  14. Nondestructive evaluation of potential quality of creosote-treated piles removed from service

    Science.gov (United States)

    Xiping. Wang; Robert J. Ross; John R. Erickson; John W. Forsman; Gary D. McGinnis; Rodney C. De Groot

    2001-01-01

    Stress-wave-based nondestructive evaluation methods were used to evaluate the potential quality and modulus of elasticity (MOE) of wood from creosote-treated Douglas-fir and southern pine piles removed from service. Stress-wave measurements were conducted on each pile section. Stress-wave propagation speeds were obtained to estimate the MOE of the wood. Tests were then...

  15. Effect of heat build-up on carbon emissions in chimato compost piles ...

    African Journals Online (AJOL)

    A study was conducted to determine impacts of heat build-up of chimato compost piles TD0, TD20, TD40, TD50, TD60, TD80 and TD100, made by blending maize stalks with 0, 20, 40, 50, 60, 80 and 100% Tithonia diversifolia, respectively, on carbon losses and emissions during composting. Compost piles temperatures ...

  16. Physical deterioration of preservative treated poles and pilings exposed to salt water

    Science.gov (United States)

    Grant T. Kirker; Jessie Glaeser; Stan T. Lebow; Frederick Green III; Carol A. Clausen

    2011-01-01

    This report details the results of laboratory analyses of wooden pilings sent to the USDA Forest Products Laboratory in March 2011. These samples were removed from coastal wooden posts, poles, piles, and deck boards. A total of 22 samples, consisting of either core borings or surface fiber samples, were removed from four installations along the South Carolina coast....

  17. RATE-DEPENDENT PULL-OUT BEARING CAPACITY OF PILES BY SIMILITUDE MODEL TESTS USING SEEPAGE FORCE

    Science.gov (United States)

    Kato, Tatsuya; Kokusho, Takaji

    Pull-out test of model piles was conducted by varying the pull-out velocity and skin friction of piles using a seepage force similitude model test apparatus. Due to the seepage consolidation under the pressure of 150kPa, the effective stress distribution in a prototype saturated soil of 17m could be successfully reproduced in the model ground of 28cm thick, in which the pull-out tests were carried out. The pull-out load rose to a peak value at small displacement, and then decreased to a residual value. At the same time, pore pressure in the vicinity of the pile decreased due to suction near the tip and the positive dilatancy near the pile skin. The maximum pull-out load, pile axial load, side friction and the corresponding displacement increased dramatically with increasing pull-out velocity. It was found that these rate-dependent trends become more prominent with increasing skin friction.

  18. CMHC research project: Testing of air barriers construction details: Report

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This project was conducted to quantify the air leakage characteristics of the header joist, the electric outlets, and the window openings in wood-frame walls. The study evaluated the sealed internal membrane method, where polyethylene sheet and sealant provide the air barrier; the external air barrier method, which uses a continuous vapour permeable membrane (spun-bonded olefin film), sandwiched between two layers of external wall sheathing; and the airtight drywall method, where the interior gypsum board finish, together with framing materials and gaskets, are used as the air barrier. In addition, the traditional approach to wood-frame wall construction, where no special attention is given to achieving a continuous air barrier, was evaluated for comparison.

  19. 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...

  20. Protection measurements on the Ulysse pile during its start-up

    International Nuclear Information System (INIS)

    Tattegrain, A.; Satge, H.

    1963-01-01

    The authors report measurements which aimed at verifying protection calculations made for the Ulysse atomic pile. They measured thermal, epithermal flows and the fast flow (when high enough to be measured). They also measured the gamma flow in some parts of the reactor. The authors describe the protections present on the different faces of the pile. These are made of baryte concrete and borated concrete. They indicate the detectors used to measure the different flows, and discuss the results obtained in the different channels

  1. Load and resistance factor design of bridge foundations accounting for pile group-soil interaction.

    Science.gov (United States)

    2015-11-01

    Pile group foundations are used in most foundation solutions for transportation structures. Rigorous and reliable pile design methods are : required to produce designs whose level of safety (probability of failure) is known. By utilizing recently dev...

  2. Pulse pile-up in nuclear particle detection systems with rapidly varying counting rates

    International Nuclear Information System (INIS)

    Datlowe, D.W.

    1977-01-01

    Pulse pile-up in nuclear particle detection systems is the distortion of the measured pulse height distribution which occurs when there is a significant probability that more than one particle will arrive within the detector resolving time. This paper treats the problem in cases where the probability of pile-up varies on a time scale comparable to the rise time of the detector system electronics. These variations introduce structure into the pulse height distributions which cannot occur for a time-independent pile-up probability. Three classes of problems which exemplify these effects are as follows: 1) Pile-up rejection circuits. 2) Cascaded nuclear decays, in which the lifetime for emission of a second X-ray is comparable to the detector rise time. 3) Bursts of particles where the intensity is modulated on a time scale comparable to the detector rise time. These problems are solved computationally by an extension of a numerical technique previously developed. (Auth.)

  3. Integration of Small-Diameter Wood Harvesting in Early Thinnings using the Two pile Cutting Method

    Energy Technology Data Exchange (ETDEWEB)

    Kaerhae, Kalle (Metsaeteho Oy, P.O. Box 101, FI-00171 Helsinki (Finland))

    2008-10-15

    Metsaeteho Oy studied the integrated harvesting of industrial roundwood (pulpwood) and energy wood based on a two-pile cutting method, i.e. pulpwood and energy wood fractions are stacked into two separate piles when cutting a first-thinning stand. The productivity and cost levels of the integrated, two-pile cutting method were determined, and the harvesting costs of the two-pile method were compared with those of conventional separate wood harvesting methods. In the time study, when the size of removal was 50 dm3, the productivity in conventional whole-tree cutting was 6% higher than in integrated cutting. With a stem size of 100 dm3, the productivity in whole-tree cutting was 7% higher than in integrated cutting. The results indicated, however, that integrated harvesting based on the two-pile method enables harvesting costs to be decreased to below the current cost level of separate pulpwood harvesting in first thinning stands. The greatest cost-saving potential lies in small-sized first thinnings. The results showed that, when integrated wood harvesting based on the two-pile method is applied, the removals of both energy wood and pulpwood should be more than 15-20 m3/ha at the harvesting sites in order to achieve economically viable integrated procurement

  4. From the pile of Volta to fuel cells

    CERN Multimedia

    2000-01-01

    Volta designed his pile by associating two different metals and liquid conducting electricity. He recognized the possibility of increasing the "voltage" by placing cells in series (a pile). This invention led to a wonderful development of science and technology, including the concept of fuel cell in 1839 by GROVE. But efficient research began only in the 20th century after the development of electrochemical thermodynamics by Nemst. His assistants conducted research on fuel cell designed by Bacon before world warII, developed NASA for the Apollo space flights. Research for effecient and clean electricity generation has led to the defferent kinds of fuel cells now under development (APC, PAPC, PAMPC, MCPC and SOPC) which will be briefly described with their applications.

  5. MODEL TESTS AND 3D ELASTIC FINITE ELEMENT ANALYSIS FOR STEEL PIPE PILES WITH WINGS IN STALLED IN SOIL CEMENT COLUMN

    Science.gov (United States)

    Tamai, Toshiyuki; Teramoto, Shuntarou; Kimura, Makoto

    Steel pipe piles with wings installed in soil cement column is a composite foundation of pile consisting of soil improvement with cement and steel pipe with wings. This type of pile shows higher vertical bearing capacity when compared to steel pipe piles that are installed without soil cement. It is thought the wings contribute to higher bearing capacity of this type of piles. The wings are also thought to play the role of structural unification of pile foundations and load transfer. In this study, model test and 3D elastic finite element analysis was carried out in order to elucidate the effect of wings on the structural unification of pile foundation and the load transfer mechanism. Firstly, the model test was carried out in order to grasp the influence of pile with and without wings, the shape of wings of the pile and the unconfined compression strength of the soil cement on the structural unification of the pile foundation. The numerical analysis of the model test was then carried out on the intermediate part of the pile foundation with wings and mathematical model developed. Finally load tran sfer mechanism was checked for the entire length of the pile through this mathematical model and the load sharing ratio of the wings and stress distribution occurring in the soil cement clarified. In addition, the effect of the wing interval on the structural unification of the pile foundation and load transfer was also checked and clarified.

  6. In-pile loop experiments in water chemistry and corrosion

    International Nuclear Information System (INIS)

    Kysela, J.; Jindrich, K.; Masarik, V.; Fric, Z.; Chotivka, V.; Hamerska, H.; Vsolak, R.; Erben, O.

    1986-08-01

    Methods and techniques used were as follows: (a) Method of polarizing resistance for remote monitoring of instantaneous rate of uniform corrosion. (b) Out-of-pile loop at the temperature 350 degC, pressure 19 MPa, circulation 20 kgs/h, testing time 1000 h. (c) High temperature electromagnetic filter with classical solenoid and ball matrix for high pressure filtration tests. (d) High pressure and high temperature in-pile water loop with coolant flow rate 10 000 kgs/h, neutron flux in active channel 7x10 13 n/cm 2 .s, 16 MPa, 330 degC. (e) Evaluation of experimental results by chemical and radiochemical analysis of coolant, corrosion products and corrosion layer on surface. The results of measurements carried out in loop facilities can be summarized into the following conclusions: (a) In-pile and out-of-pile loops are suitable means of investigating corrosion processes and mass transport in the nuclear power plant primary circuit. (b) In studying transport phenomena in the loop, it is necessary to consider the differences in geometry of the loop and the primary circuit, mainly the ratio of irradiated and non-irradiated surfaces and volumes. (c) In the experimental facility simulating the WWER-type nuclear power plant primary circuit, solid suspended particles of a chemical composition corresponding most frequently to magnetite or nickel ferrite, though with non-stoichiometric composition Me x 2+ Fe 3-x 3+ O 4 , were found. (d) Continuous filtration of water by means of an electromagnetic filter removing large particles of corrosion products leads to a decrease in radioactivity of the outer epitactic layer only. The effect of filtration on the inner topotactic layer is negligible

  7. NEET In-Pile Ultrasonic Sensor Enablement-FY 2012 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    JE Daw; JL Rempe; BR Tittmann; B Reinhardt; P Ramuhalli; R Montgomery; HT Chien

    2012-09-01

    Several Department Of Energy-Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development, Advanced Reactor Concepts, Light Water Reactor Sustainability, and Next Generation Nuclear Plant programs, are investigating new fuels and materials for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials when irradiated. The Nuclear Energy Enabling Technology (NEET) Advanced Sensors and Instrumentation (ASI) in-pile instrumentation development activities are focused upon addressing cross-cutting needs for DOE-NE irradiation testing by providing higher fidelity, real-time data, with increased accuracy and resolution from smaller, compact sensors that are less intrusive. Ultrasonic technologies offer the potential to measure a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes, under harsh irradiation test conditions. There are two primary issues associated with in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. Due to the harsh nature of in-pile testing, and the range of measurements that are desired, an enhanced signal processing capability is needed to make in-pile ultrasonic sensors viable. This project addresses these technology deployment issues.

  8. In-pile loop experiments in water chemistry and corrosion

    International Nuclear Information System (INIS)

    Kysela, J.

    1986-09-01

    Results on the study of Zr-1% Nb alloy corrosion, in out-of and in-pile loops simulating the working conditions of the VVER-440 reactor (Soviet, PWR type), covered the time period May 1982-April 1986 were reported, as well as, results on transport and filtration of corrosion products. Methods and techniques used in the study included remote measurement of corrosion rate by polarizing resistance, out-of-pile loop at the temperature 350 deg. C, pressure 19 MPa, circulation 20 kgs/h and in-pile water loop with constant flow rate 10,000 kgs/h, pressure 16 MPa, temperature 330 deg. C and neutron flux 7x10 13 n/cm 2 .s. It was shown that solid suspended particles with chemical composition corresponding most frequently to magnetite or nickelous ferrite, though with non-stoichiometric composition Me x 2+ Fe 3- x 3+ O 4 were found. Continuous filtration of water by means of electromagnetic filter leads to a decrease of radioactivity of the outer epitactic layer only. Effect of filtration on the inner topotactic layer is negligible. The corrosion rates for the above-mentioned parameters are given

  9. The response of pile-guided floats subjected to dynamic loading : volume I final report.

    Science.gov (United States)

    2014-08-01

    Pile : - : Guided floats can be a desirable alternative to stationary berthing structures. Both floats and guide piles are subjected to dynamic : forces such as wind generated waves and impacts from vessels. This project developed a rational basis fo...

  10. Development of enclosure technique of tag gas for in-pile creep test

    International Nuclear Information System (INIS)

    Izaki, Toru; Ichikawa, Shoichi; Soroi, Masatoshi; Ito, Chikara

    2004-01-01

    Outline of the enclosure technique of tag gas for in-pile creep test is stated. In order to carry out in-pile creep test, the sample can enclose tag gas before the test and then the sample is inserted into MARICO-2 (Material Testing Rig with Temperature Control) in FBR 'JOYO' MK-III for the irradiation test. Outline of in-pile creep test using tag gas, enclosure system of tag gas, detection of a part of broken sample and identification of sample are explained. 126-, 128-, 129-, 131-, 132-, and 134-Xe are used as tag gases. The samples are identified by RIMS (Laser Resonance Ionization Mass Spectroscopy) in ppt order. ODS ferritic steel will be tested by the method in the next step. (S.Y.)

  11. Comparison between Dynamic Responses of Hollow and Solid Piles for Offshore Wind Turbine Foundations

    DEFF Research Database (Denmark)

    Bayat, Mehdi; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2013-01-01

    the dynamic behavior of soil and interaction between soil and piles. To avert damage to offshore foundation, it becomes necessary to identify and quantify the soil-structure interaction and the related damping effects on the system. In this study, a single pile is investigated by means of boundary integral...... equations. The pile is modeled as a solid or hollow cylinder and the dynamic excitation is applied vertically. The surface along the entire interface is considered rough and with full contact between the soil and the structure. Somigliana’s identity, Betti’s reciprocal theorem and Green’s function...... are employed to derive the dynamic stiffness of pile, assuming that the soil is a linear viscoelastic medium. The dynamic stiffness is compared for solid and hollow cylinders by considering different values of material properties including the material damping. Modes of resonance and anti...

  12. Wave Run-up on Slender Piles in Design Conditions

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Frigaard, Peter; Damsgaard, M. L.

    2011-01-01

    in the design of Horns Reef 1. As a consequence damage was observed on the platforms. This has been the situation for several sites and design tools for platform loads are lacking. As a consequence a physical model test study was initiated at Aalborg University to clarify wave run-up on cylindrical piles...... to the pile an empirical factor is included on the velocity head. The evaluation of the calculation model shows that an accurate design rule can be established even in breaking wave conditions. However, calibration of a load model showed that it was necessary to increase the run-up factor on the velocity head...

  13. Collapse mechanisms and strength prediction of reinforced concrete pile caps

    DEFF Research Database (Denmark)

    Jensen, Uffe G.; Hoang, Linh Cao

    2012-01-01

    . Calculations have been compared with nearly 200 test results found in the literature. Satisfactory agreement has been found. The analyses are conducted on concentrically loaded caps supported by four piles. The paper briefly outlines how the approach may be extended to more complicated loadings and geometries......This paper describes an upper bound plasticity approach for strength prediction of reinforced concrete pile caps. A number of collapse mechanisms are identified and analysed. The procedure leads to an estimate of the load-carrying capacity and an identification of the critical collapse mechanism...

  14. Beam parameters observations during the second high pile-up collisions fill in 2011

    CERN Document Server

    Trad, G; Buffat, X; Calaga, R; Cornelis, K; Herr, W; Jacquet, D; Papotti, G; Schaumann, M; Venturini Delsolaro, W

    2012-01-01

    On the 25th of October 2011, a physics fill( Fill nr 2252) was dedicated to providing ATLAS & CMS with high pile-up collisions. A peak pile-up (number of inelastic interactions per crossing) μ of almost 35 was achieved. Part of the test was also to bring the pile-up to values < 0.5 and this was achieved by separating the beams in steps. The Head-On collisions were restored after each IP separation to study its effects. In this note observations of the beam parameters evolution (bunch current, emittances and length) are presented. Some conclusions are drawn and suggestions for future MDs are discussed.

  15. Assessment of the potential quality of preservative-treated pilings removed from service : [abstract

    Science.gov (United States)

    Xiping Wang; John W. Forsman; John R. Erickson; Robert J. Ross; Douglas J. Gardner; Gary D. McGinnis; Rodney C. DeGroot

    1999-01-01

    Preservative-treated wood products are important construction materials. Preservative-treated wood pilings, after removal from service, constitute a major disposal problem for managers of waterfront facilities. For example, approximately 7,000 to 8,000 tons of mechanically or biologically deteriorated wood pilings are currently removed from U.S. naval facilities...

  16. Improving agreement between static method and dynamic formula for driven cast-in-place piles.

    Science.gov (United States)

    2013-06-01

    This study focuses on comparing the capacities and lengths of piling necessary as determined with a static method and with a dynamic formula. Pile capacities and their required lengths are determined two ways: 1) using a design and computed method, s...

  17. In-pile Instrumentation Development

    International Nuclear Information System (INIS)

    Vermeeren, L.

    2005-01-01

    Advanced irradiations in research reactors require the on-line monitoring of crucial parameters like neutron fluxes, gamma dose rates, central fuel rod temperatures, fission gas release pressures and small geometry changes. Our activities in this field aim at a detailed understanding of the sensor behaviour in the irradiation conditions in order to extract reliable real-time information. The objectives of work performed by SCK-CEN are to study of the on-line in-pile measurement of gamma and neutron fluxes in real time and to investigate parasitic radiation-induced signals in instrumentation cables

  18. Natural Radionuclides in Slag/Ash Pile from Coal-Fired Power Plant Plomin

    International Nuclear Information System (INIS)

    Barisic, D.; Lulic, S.; Marovic, G.; Sencar, J.

    2001-01-01

    Full text: The coal slag/ash pile contains about one million tons of different (bottom ash, filter ash, gypsum) waste material deposited in vicinity of Plomin coal-fired power plant. Activities of 40 K, 228 Ra, 226 Ra and 238 U in materials deposited on slag/ash pile as well as in used coals were occasionally measured during past more than two and half decades of Plomin coal-fired plant operation. The radionuclides content in deposited bottom and filter ash material are related with radionuclide activities and mineral matter fraction in coals used. Up to the middle of nineties, the majority of coal used was anthracite from Istrian local mines. In that period, deposited waste material was characterised with relatively high 226 Ra and 238 U activities while potassium and thorium content was very low. When Istrian coal has been completely substituted with imported coal, uranium series radionuclide concentrations in deposited waste materials decreased significantly. Meanwhile, potassium and thorium activities in slag/ash pile material increased. It seems that slag/ash pile material generated in the last several years of Plomin coal-fired power plant operation could be generally used in cement industry without any special restriction. (author)

  19. Displacement of Pile-Reinforced Slopes with a Weak Layer Subjected to Seismic Loads

    Directory of Open Access Journals (Sweden)

    Haizuo Zhou

    2016-01-01

    Full Text Available The presence of a weak layer in a slope requires special attention because it has a negative impact on slope stability. However, limited insight into the seismic stability of slopes with a weak layer exists. In this study, the seismic stability of a pile-reinforced slope with a weak thin layer is investigated. Based on the limit analysis theory, a translational failure mechanism for an earth slope is developed. The rotational rigid blocks in the previous rotational-translational failure mechanism are replaced by continuous deformation regions, which consist of a sequence of n rigid triangles. The predicted static factor of safety and collapse mechanism in two typical examples of slopes with a weak layer compare well with the results obtained from the available literature and by using the Discontinuity Layout Optimization (DLO technique. The lateral forces provided by the stabilizing piles are evaluated using the theory of plastic deformation. An analytical solution for estimating the critical yield acceleration coefficient for the pile-reinforced slopes is derived. Based on the proposed translational failure mechanism and the corresponding critical yield acceleration coefficient, Newmark’s analytical procedure is employed to evaluate the cumulative displacement. Considering different real earthquake acceleration records as input motion, the effect of stabilizing piles and varying the spacing of piles on the cumulative displacement of slopes with a weak layer is investigated.

  20. Underwater noise generated by offshore pile driving

    NARCIS (Netherlands)

    Tsouvalas, A.

    2015-01-01

    Anthropogenic noise emission in the marine environment has always been an environmental issue of serious concern. In particular, the noise generated during the installation of foundation piles is considered to be one of the most significant sources of underwater noise pollution. This is mainly