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Sample records for sand compaction pile

  1. 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.

  2. Test work of sand compaction pile method on coal ash soil foundation. Sekitanbai jiban ni okeru sand compaction pile koho no shiken seko

    Energy Technology Data Exchange (ETDEWEB)

    Goto, K.; Maeda, S.; Shibata, T. (The Kansai Electric Power Co. Inc., Osaka (Japan))

    1992-01-25

    As an electric power supply source after the 1990 {prime}s, Nos. 5 and 6 units are additionally being constructed by Kansai Electric Power in its Himeji Power Station No.1 which is an exclusively LNG burning power station. The additional construction site of those units is of soil foundation reclaimed with coal ash which was used residual product in the existing No.1 through No.4 units. As a result of soil foundation survey, the coal ash layer and sand layer were known to be of material to be possibly liquidized at the time of earthquake. As measures against the liquidization, application was basically made of a sand compaction pile (SCP) method which is economical and abundant in record. However, that method was so short of record in the coal ash layer that its evaluation was difficult in soil reforming effect. Therefore, its applicability was evaluated by a work test on the site, which resulted in a confirmation that the coal ash as well as the sand can be sufficiently reformed by the SCP method. Started in September, 1991, the additional construction of Nos. 5 and 6 units in Himeji Power Station No.1 uses a 1.5m pitch SCP method to reform the soil foundation. 3 refs., 10 figs., 1 tab.

  3. 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.

  4. 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....

  5. 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.

  6. 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.

  7. 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....

  8. 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.

  9. Effects of sand compaction pile (SCP) driving on the strength of clay outside the improved area; Sand compaction pile no dasetsu ga jiban kairyo ikigai no nendo jiban no kyodo ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, H. [Yamaguchi University, Yamaguchi (Japan); Takahashi, S. [Ministry of Transport, Tokyo (Japan); Fujiwara, K. [Penta-Ocean Construction Co. Ltd., Tokyo (Japan); Kitayama, N. [Fukken Co. Ltd., Hiroshima (Japan)

    1998-06-21

    This paper describes effects of the disturbance by the sand compaction pile (SCP) driving operations on the shear strength of clay outside the improved area and the border of region affected by the SCP driving. About 1,400 soil specimens were taken before and after the SCP driving inside and outside the improved area during the foundation improvement at Tokuyama-Shimomatsu Port in Yamaguchi Prefecture. Soil test data of the specimens and strength characteristics of disturbed clay specimens were investigated through the laboratory experiments. The results obtained are as follows. According to the multi-directional simple shear test results, the shear strength immediately after the cyclic shear decreased in 10 to 30% compared with that before the cyclic shear. When recompaction was conducted before the cyclic shear, however, it increased in 50% compared with that before the cyclic shear. The strength of clay decreased by the SCP driving even outside the improved area. When the internal frictional angle of clay, friction coefficient of the improved boundary and driving depth of SCP were determined, it was possible to estimate an area affected by the SCP driving using a combined sliding plane. 21 refs., 18 figs.

  10. 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

  11. 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....

  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. 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

  14. 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.

  15. 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...

  16. 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....

  17. 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...

  18. Seismic tests of a pile-supported structure in liquefiable sand using large-scale blast excitation

    International Nuclear Information System (INIS)

    Kamijo, Naotaka; Saito, Hideaki; Kusama, Kazuhiro; Kontani, Osamu; Nigbor, Robert

    2004-01-01

    Extensive, large-amplitude vibration tests of a pile-supported structure in a liquefiable sand deposit have been performed at a large-scale mining site. Ground motions from large-scale blasting operations were used as excitation forces for vibration tests. A simple pile-supported structure was constructed in an excavated 3 m-deep pit. The test pit was backfilled with 100% water-saturated clean uniform sand. Accelerations were measured on the pile-supported structure, in the sand in the test pit, and in the adjacent free field. Excess pore water pressures in the test pit and strains of one pile were also measured. Vibration tests were performed with six different levels of input motions. The maximum horizontal acceleration recorded at the adjacent ground surface varied from 20 Gals to 1353 Gals. These alternations of acceleration provided different degrees of liquefaction in the test pit. Sand boiling phenomena were observed in the test pit with larger input motions. This paper outlines vibration tests and investigates the test results

  19. Scour at Vertical Piles in Sand-Clay Mixtures under Waves

    DEFF Research Database (Denmark)

    Dey, Subhasish; Helkjær, Anders; Sumer, B. Mutlu

    2011-01-01

    Marine sediments often contain sand-clay mixtures in widely varying proportions. This study presents the results of equilibrium scour and time variation of scour depths at circular piles embedded vertically in clay alone and sand-clay mixed beds under waves. Experiments were conducted in a wave...... flume with different proportions of sand-clay mixtures as bed sediments. Test results for the cases of steady current and sand alone under waves are used as references. The equilibrium scour depth reduces with an increase in clay proportion n (by weight) in a sand-clay mixture. Interestingly, the scour...

  20. 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....

  1. 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....

  2. 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...

  3. 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)

  4. Compressive Strength of Compacted Clay-Sand Mixes

    Directory of Open Access Journals (Sweden)

    Faseel Suleman Khan

    2014-01-01

    Full Text Available The use of sand to improve the strength of natural clays provides a viable alternative for civil infrastructure construction involving earthwork. The main objective of this note was to investigate the compressive strength of compacted clay-sand mixes. A natural clay of high plasticity was mixed with 20% and 40% sand (SP and their compaction and strength properties were determined. Results indicated that the investigated materials exhibited a brittle behaviour on the dry side of optimum and a ductile behaviour on the wet side of optimum. For each material, the compressive strength increased with an increase in density following a power law function. Conversely, the compressive strength increased with decreasing water content of the material following a similar function. Finally, the compressive strength decreased with an increase in sand content because of increased material heterogeneity and loss of sand grains from the sides during shearing.

  5. Improved soil characterization for pipe piles in sand in API RP-2A

    International Nuclear Information System (INIS)

    Hossain, M.K.; Briaud, J.L.

    1993-01-01

    In the offshore, most foundations are steel pipe piles and most of them are designed using the API RP 2A guidelines. For axial capacity of piles in sand the current guidelines in many cases show definite discrepancies when compared against actual load capacities of piles. An updated data base analysis shows that there are three major weaknesses in the current guidelines with respect to soil characterization: (a) the consideration of the lateral earth pressure coefficient, K, as a constant (1.0 or 0.8); (b) the consideration of the unit point bearing resistance, q, as a linear function of depth; and (c) the absence of an unambiguous soil parameter determination process based on reliable in-situ test results. In this paper, specific modifications to the current API RP 2A guidelines are proposed on the basis of a data base analysis to account for the discrepancies arising from (a), (b), and (c) above. These modifications will reduce the discrepancies in the current API RP 2A method and increase the accuracy of the prediction of axial capacity of pipe piles in sand. Furthermore this will make the method fundamentally more consistent with soil behavior in deep foundations

  6. 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.

  7. 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.

  8. 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...

  9. The definition of necessary axial force for extension of initial borehole for soft soil compaction process design

    Directory of Open Access Journals (Sweden)

    Ter-Martirosyan Zaven

    2016-01-01

    Full Text Available The article provides an analytical solution of the soil pile and surrounding soil cylinder interaction problem, with the possibility of extension of the pile shaft in its construction. Presents a closed solution for determination of radial and tangential stresses in the process of expansion of the pile shaft, as well as the minimum vertical force sufficient for the crushing of the pile material and move it in radial direction to the specified value. The problem is most actual for compacted soil bases with use of piles-drains of sand and sand-gravel mixture.

  10. Centrifuge modelling of large diameter pile in sand subject to lateral loading

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    and cyclic behaviour of large diameter rigid piles in dry sand by use of physical modelling. The physical modelling has been carried out at Department of Civil Engineering at the Danish Technical University (DTU.BYG), in the period from 2005 to 2009. The main centrifuge facilities, and especially...... the equipment for lateral load tests were at the start of the research in 2005 outdated and a major part of the work with the geotechnical centrifuge included renovation and upgrading of the facilities. The research with respect to testing of large diameter piles included:  Construction of equipment...... with embedment lengths of 6, 8 and 10 times the diameter. The tests have been carried out with a load eccentricity of 2.5 m to 6.5 m above the sand surface. The present report includes a description of the centrifuge facilities, applied test procedure and equipment along with presentation of the obtained results....

  11. Evaluation of the Load-Displacement Relationships for Large-Diameter Piles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Brodbaek, K. T.; Moller, M.

    2009-01-01

    For laterally loaded piles in sand with diameters up to 6 m, e.g. monopiles used as foundations for offshore wind turbines, there is no approved design procedure. The p-y curve method, given in offshore design regulations, is usually employed for the design of monopiles. However, this method was ...

  12. State of the Art for Design and Construction of Sand Compaction Piles

    Science.gov (United States)

    1987-11-01

    Walz, Headquarters, US Army Corps of Engineers (HQUSACE), was REMR Technical Monitor. The REMR Overview Committee, consisted of Mr. John R. Nikel ... Wire Vibrator Hopper Casing Pipe Air Line Power Line Sand Skip Bucket Front End Loader Figure 2. Typical equipment used to construct a sand...8217~~~~--­ Rubber Packing Wire Inlet for air to close valve and press sand down ..,...__ Air lnl~ot: Figure 5. Special valve used to seal the casing when

  13. Experimental study on swelling character of statics-compacted bentonite-sand mixture

    International Nuclear Information System (INIS)

    Cui Suli; Zhang Huyuan; Liu Jisheng; Liang Jian

    2010-01-01

    In the high-level radioactive waste (HLW) geological disposal projects barrier system, there are two types for constructing buffer/backfill material in preconceived: locale field-pressed and locale-build by prefab lock. Statics-Compacted is needed for both footrill padding in the locale field-pressed and locale-build by prefab lock. Laboratory tests were conducted on statics-compacted mixture of GMZ001 bentonite and quartz sand in different addition. The results obtained indicated that in the semi-log coordinates, the form of the P-time and e-time curves were sigmoid,the same as dynamic-compacted specime. The swelling character of statics-compacted specime were also as well as dynamic-compacted specime, that is with the increase of initial dry density, the maximum swelling pressure were exponential increase and maximum swelling strain increase linearly. These made it clear that the methods of making specime have no effect on the swelling character of bentonite-sand mixture, so methods for constructing buffer/backfill material can be selected free as needed in the construction site. The validity of regression relationship received by dynamic-compacted specime test was verified, and the coefficients for the regression equation were revised in a greater range of initial dry density. Based on the comprehensive analysis of experimental results, it is concluded that addition of 10-30% quartz sand and 1.60-1.80 g/cm 3 for initial dry density to GMZ001 bentonite-sand mixture is suitable for the swelling quality. (authors)

  14. Understanding and Mitigating Reservoir Compaction: an Experimental Study on Sand Aggregates

    Science.gov (United States)

    Schimmel, M.; Hangx, S.; Spiers, C. J.

    2016-12-01

    Fossil fuels continue to provide a source for energy, fuels for transport and chemicals for everyday items. However, adverse effects of decades of hydrocarbons production are increasingly impacting society and the environment. Production-driven reduction in reservoir pore pressure leads to a poro-elastic response of the reservoir, and in many occasions to time-dependent compaction (creep) of the reservoir. In turn, reservoir compaction may lead to surface subsidence and could potentially result in induced (micro)seismicity. To predict and mitigate the impact of fluid extraction, we need to understand production-driven reservoir compaction in highly porous siliciclastic rocks and explore potential mitigation strategies, for example, by using compaction-inhibiting injection fluids. As a first step, we investigate the effect of chemical environment on the compaction behaviour of sand aggregates, comparable to poorly consolidated, highly porous sandstones. The sand samples consist of loose aggregates of Beaujean quartz sand, sieved into a grainsize fraction of 180-212 µm. Uniaxial compaction experiments are performed at an axial stress of 35 MPa and temperature of 80°C, mimicking conditions of reservoirs buried at three kilometres depth. The chemical environment during creep is either vacuum-dry or CO2-dry, or fluid-saturated, with fluids consisting of distilled water, acid solution (CO2-saturated water), alkaline solution (pH 9), aluminium solution (pH 3) and solution with surfactants (i.e., AMP). Preliminary results show that compaction of quartz sand aggregates is promoted in a wet environment compared to a dry environment. It is inferred that deformation is controlled by subcritical crack growth when dry and stress corrosion cracking when wet, both resulting in grain failure and subsequent grain rearrangement. Fluids inhibiting these processes, have the potential to inhibit aggregate compaction.

  15. Time-independent compaction behavior of quartz sands

    NARCIS (Netherlands)

    Brzesowsky, R. H.; Spiers, C. J.|info:eu-repo/dai/nl/304829323; Peach, C. J.|info:eu-repo/dai/nl/082101906; Hangx, Suzanne|info:eu-repo/dai/nl/30483579X

    Mechanisms such as grain rearrangement, coupled with elastic deformation and grain breakage, are believed to play an important role in the time-independent compaction of sands, controlling porosity and permeability reduction during burial of clastic sediments and during depletion of highly porous

  16. Strength and Compaction Analysis of Sand-Bentonite-Coal Ash Mixes

    Science.gov (United States)

    Sobti, Jaskiran; Singh, Sanjay Kumar

    2017-08-01

    This paper deals with the strength and compaction characteristics of sand-bentonite-coal ash mixes prepared by varying percentages of sand, bentonite and coal ash to be used in cutoff walls and as a liner or cover material in landfills. The maximum dry density (MDD) and optimum moisture content (OMC) of sand-bentonite mixes and sand-bentonite-coal ash mixes were determined by conducting the standard proctor test. Also, the strength and stiffness characteristics of soil mixes were furnished using unconfined compressive strength test. The results of the study reveal influence of varying percentages of coal ash and bentonite on the compaction characteristics of the sand-bentonite-coal ash mixes. Also, validation of a statistical analysis of the correlations between maximum dry density (MDD), optimum moisture content (OMC) and Specific Gravity (G) was done using the experimental results. The experimental results obtained for sand-bentonite, sand-bentonite-ash and coal ash-bentonite mixes very well satisfied the statistical relations between MDD, OMC and G with a maximum error in the estimate of MDD being within ±1 kN/m3. The coefficient of determination (R2) ranged from 0.95 to 0.967 in case of sand-bentonite-ash mixes. However, for sand-bentonite mixes, the R2 values are low and varied from 0.48 to 0.56.

  17. 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

  18. 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)

  19. 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.

  20. Understanding the mechanical and acoustical characteristics of sand aggregates compacting under triaxial conditions

    Science.gov (United States)

    Hangx, Suzanne; Brantut, Nicolas

    2016-04-01

    Mechanisms such as grain rearrangement, coupled with elastic deformation, grain breakage, grain rearrangement, grain rotation, and intergranular sliding, play a key role in determining porosity and permeability reduction during burial of clastic sediments. Similarly, in poorly consolidated, highly porous sands and sandstones, grain rotation, intergranular sliding, grain failure, and pore collapse often lead to significant reduction in porosity through the development of compaction bands, with the reduced porosity and permeability of such bands producing natural barriers to flow within reservoir rocks. Such time-independent compaction processes operating in highly porous water- and hydrocarbon-bearing clastic reservoirs can exert important controls on production-related reservoir deformation, subsidence, and induced seismicity. We performed triaxial compression experiments on sand aggregates consisting of well-rounded Ottawa sand (d = 300-400 μm; φ = 36.1-36.4%) at room temperature, to systematically investigate the effect of confining pressure (Pceff = 5-100 MPa), strain rate (10-6-10-4 s-1) and chemical environment (decane vs. water; Pf = 5 MPa) on compaction. For a limited number of experiments grain size distribution (d = 180-500 μm) and grain shape (subangular Beaujean sand; d = 180-300 μm) were varied to study their effect. Acoustic emission statistics and location, combined with microstructural and grain size analysis, were used to verify the operating microphysical compaction mechanisms. All tests showed significant pre-compaction during the initial hydrostatic (set-up) phase, with quasi-elastic loading behaviour accompanied by permanent deformation during the differential loading stage. This permanent volumetric strain involved elastic grain contact distortion, particle rearrangement, and grain failure. From the acoustic data and grain size analysis, it was evident that at low confining pressure grain rearrangement controlled compaction, with grain

  1. Experimental studies in Ultrasonic Pulse Velocity of roller compacted concrete pavement containing fly ash and M-sand

    Directory of Open Access Journals (Sweden)

    S. Krishna Rao

    2016-07-01

    Full Text Available This paper presents the experimental investigation results of Ultrasonic Pulse Velocity (UPV tests conducted on roller compacted concrete pavement (RCCP material containing Class F fly ash of as mineral admixture. River sand, M-sand and combination of M-sand and River sand are used as fine aggregate in this experimental work. Three types of fly ash roller compacted concrete mixes are prepared using above three types of fine aggregates and they are designated as Series A (River sand, Series B (manufactured sand and Series C (combination of River sand and M-sand. In each series the fly ash content in place of cement is varied from 0% to 60%. In each series and for different ages of curing (i.e 3, 7, 28 and 90 days forty two cube specimens are cast and tested for compressive strength and UPV. The UPV results of fly ash containing roller compacted concrete pavement (FRCCP show lower values at all ages from 3 days to 90 days in comparison with control mix concrete (0% fly ash in all mixes. However, it is also observed that Series B and C mixes containing fly ash show better results in UPV values, compressive strength and Dynamic Elastic Modulus in comparison to Series A mixes with fly ash. Relationships between compressive strength of FRCCP and UPV and Dynamic Elastic Modulus are proposed for all series mixes. A new empirical equation is proposed to determine the Dynamic Elastic Modulus of FRCCP. Keywords: Compressive strength, Dynamic Elastic Modulus, Fly ash, Roller compacted concrete pavement, Ultrasonic Pulse Velocity

  2. 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.

  3. 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....

  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. Effect of class F fly ash on fine sand compaction through soil stabilization.

    Science.gov (United States)

    Mahvash, Siavash; López-Querol, Susana; Bahadori-Jahromi, Ali

    2017-03-01

    This paper presents the results of an experimental investigation carried out to evaluate the effect of fly ash (FA) on fine sand compaction and its suitability as a material for embankments. The literature review demonstrates the lack of research on stabilization of sandy material using FA. The study is concerned with the role of FA content in stabilized soil physical characteristics. The main aim of this paper is to determine the optimum quantity of FA content for stabilization of this type of soil. This is achieved through particle size distribution and compaction (standard proctor) tests. The sand was stabilized with three proportions of FA (5%, 10% and 15%) and constant cement content of 3% was used as an activator. For better comparison, the sand was also stabilized by 3% cement only so that the effect of FA could be observed more clearly. The results were in line with the literature for other types of soil, i.e. as the % of FA increases, reduction in maximum dry density and higher optimum moisture content were observed.

  6. Effect of class F fly ash on fine sand compaction through soil stabilization

    Directory of Open Access Journals (Sweden)

    Siavash Mahvash

    2017-03-01

    Full Text Available This paper presents the results of an experimental investigation carried out to evaluate the effect of fly ash (FA on fine sand compaction and its suitability as a material for embankments. The literature review demonstrates the lack of research on stabilization of sandy material using FA. The study is concerned with the role of FA content in stabilized soil physical characteristics. The main aim of this paper is to determine the optimum quantity of FA content for stabilization of this type of soil. This is achieved through particle size distribution and compaction (standard proctor tests. The sand was stabilized with three proportions of FA (5%, 10% and 15% and constant cement content of 3% was used as an activator. For better comparison, the sand was also stabilized by 3% cement only so that the effect of FA could be observed more clearly. The results were in line with the literature for other types of soil, i.e. as the % of FA increases, reduction in maximum dry density and higher optimum moisture content were observed.

  7. 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.

  8. 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...

  9. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    Directory of Open Access Journals (Sweden)

    Nirmala D.B.

    2016-06-01

    Full Text Available This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37 Orthogonal Arrays (OA with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering “Nominal the better” situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  10. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    Science.gov (United States)

    Nirmala, D. B.; Raviraj, S.

    2016-06-01

    This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  11. Test study on relation between thaw-collapse displacement of medium sand and negative friction of single pile

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, G.; Yang, W. [China University of Mining and Technology, Xuzhou (China). College of Architecture and Civil Engineering

    1999-11-01

    Based on simulation tests, the change of thaw-collapse displacement of saturated medium sand and the relation between negative friction of single pile and thaw-collapse displacement are investigated . In the separating ice and thawing stages, the relation between separating ice surface displacement of sample and time is similarly linear, but the displacement is too small in the redistribution stage of grains. Corresponding to these two stages, the displacement of sample grain framework surface can be divided into similarly linear and non-linear factions. The contribution of the non-linear section comes from grain redistribution after thawing. The negative friction of single pile shows good linear relation following the thawing process. But the producing and increasing mechanisms of negative friction are not the same in the two stages. During the stage of grain redistribution, the displacement of sample grain framework surface occupies only 9.7% of the total displacement, while the negative friction has increased by 18% or so. 6 refs., 7 figs.

  12. 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....

  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. 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

  15. 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.

  16. 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.

  17. Permeability Characteristics of Compacted and Stabilized Clay with Cement, Peat Ash and Silica Sand

    OpenAIRE

    Seyed Esmaeil Mousavi; Leong Sing Wong

    2016-01-01

    The present paper investigates the influence of stabilization with cement, peat ash, and silica sand on permeability coefficient (kv) of compacted clay, using a novel approach to stabilize the clay with peat ash as a supplementary material of cement in the compacted and stabilized soil. In order to assess the mentioned influence, test specimens of both untreated and stabilized soil have been tested in the laboratory so that their permeability could be evaluated. Falling head and one dimension...

  18. 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

  19. 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...

  20. On Pluvial Compaction of Sand

    DEFF Research Database (Denmark)

    Jacobsen, Moust

    At the Institute of Civil Engineering in Aalborg model tests on dry sand specimens have been carried out during the last five years. To reduce deviations in test results, the sand laying technique has been carefully studied, and the sand mass spreader constructed. Preliminary results have been...

  1. 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.

  2. Compaction creep of sands due to time-dependent grain failure : Effects of chemical environment, applied stress, and grain size

    NARCIS (Netherlands)

    Brzesowsky, R. H.; Hangx, S. J. T.|info:eu-repo/dai/nl/30483579X; Brantut, N.; Spiers, C. J.|info:eu-repo/dai/nl/304829323

    2014-01-01

    Time-dependent brittle creep plays a role in controlling compaction of sands and sandstones under upper crustal conditions, influencing phenomena such as production-induced reservoir compaction, surface subsidence, and induced seismicity. Brittle creep also plays a role in determining the mechanical

  3. Laboratory determination of migration of Eu(III) in compacted bentonite–sand mixtures as buffer/backfill material for high-level waste disposal

    International Nuclear Information System (INIS)

    Zhou, Lang; Zhang, Huyuan; Yan, Ming; Chen, Hang; Zhang, Ming

    2013-01-01

    For the safety assessment of geological disposal of high-level radioactive waste (HLW), the migration of Eu(III) through compacted bentonite–sand mixtures was measured under expected repository conditions. Under the evaluated conditions, advection and dispersion is the dominant migration mechanism. The role of sorption on the retardation of migration was also evaluated. The hydraulic conductivities of compacted bentonite–sand mixtures were K=2.07×10 −10 –5.23×10 −10 cm/s, The sorption and diffusion of Eu(III) were examined using a flexible wall permeameter for a solute concentration of 2.0×10 −5 mol/l. The effective diffusion coefficients and apparent diffusion coefficients of Eu(III) in compacted bentonite–sand mixtures were in the range of 1.62×10 –12 –4.87×10 –12 m 2 /s, 1.44×10 –14 –9.41×10 –14 m 2 /s, respectively, which has a very important significance to forecast the relationship between migration length of Eu(III) in buffer/backfill material and time and provide a reference for the design of buffer/backfill material for HLW disposal in China. - Highlights: • The migration progress of Eu(III) in compacted bentonite–sand mixtures was researched. • The hydraulic conductivity of cominpacted bentonite–sand mixtures was measured. • The migration length of Eu(III) in buffer/backfill material after a certain period of time was forecasted

  4. Microstructure and anisotropic swelling behaviour of compacted bentonite/sand mixture

    Directory of Open Access Journals (Sweden)

    Simona Saba

    2014-04-01

    Full Text Available Pre-compacted elements (disks, torus of bentonite/sand mixture are candidate materials for sealing plugs of radioactive waste disposal. Choice of this material is mainly based on its swelling capacity allowing all gaps in the system to be sealed, and on its low permeability. When emplaced in the gallery, these elements will start to absorb water from the host rock and swell. Thereby, a swelling pressure will develop in the radial direction against the host rock and in the axial direction against the support structure. In this work, the swelling pressure of a small scale compacted disk of bentonite and sand was experimentally studied in both radial and axial directions. Different swelling kinetics were identified for different dry densities and along different directions. As a rule, the swelling pressure starts increasing quickly, reaches a peak value, decreases a little and finally stabilises. For some dry densities, higher peaks were observed in the radial direction than in the axial direction. The presence of peaks is related to the microstructure change and to the collapse of macro-pores. In parallel to the mechanical tests, microstructure investigation at the sample scale was conducted using microfocus X-ray computed tomography (μCT. Image observation showed a denser structure in the centre and a looser one in the border, which was also confirmed by image analysis. This structure heterogeneity in the radial direction and the occurrence of macro-pores close to the radial boundary of the sample can explain the large peaks observed in the radial swelling pressure evolution. Another interesting result is the higher anisotropy found at lower bentonite dry densities, which was also analysed by means of μCT observation of a sample at low bentonite dry density after the end of test. It was found that the macro-pores, especially those between sand grains, were not filled by swelled bentonite, which preserved the anisotropic microstructure caused by

  5. Permeability Characteristics of Compacted and Stabilized Clay with Cement, Peat Ash and Silica Sand

    Directory of Open Access Journals (Sweden)

    Seyed Esmaeil Mousavi

    2016-06-01

    Full Text Available The present paper investigates the influence of stabilization with cement, peat ash, and silica sand on permeability coefficient (kv of compacted clay, using a novel approach to stabilize the clay with peat ash as a supplementary material of cement in the compacted and stabilized soil. In order to assess the mentioned influence, test specimens of both untreated and stabilized soil have been tested in the laboratory so that their permeability could be evaluated. Falling head and one dimensional consolidation tests of laboratory permeability were performed on the clay specimens and the chemical compositions of the materials as well as microstructure of the stabilized soil with 18% cement, 2% peat ash, and 5% silica sand were investigated, using X-ray fluorescence and scanning electron microscopy respectively. Results show that for soil stabilization with up to 8% cement content (of the dry weight of the soil, the average value of coefficient of permeability (kv is very close to that of untreated soil, whereas the kv value decreases drastically for 18% cement under identical void ratio conditions. It is further revealed that addition of 18% cement, 2% peat ash, and 5% silica sand had decreased the coefficient of permeability by almost 2.2 folds after 24 h, while about 1.7 folds increase was observed in coefficient of permeability once 13.5% of cement, 1.5% of peat ash, and 20% of silica sand were added. The partial replacement of cement with the 2% peat ash can reduce the consumption of cement for soil stabilization.

  6. The influence of sand content on swelling pressures and structure developed in statically compacted Na-bentonite

    International Nuclear Information System (INIS)

    Gray, M.N.; Cheung, S.C.H.; Dixon, D.A.

    1984-09-01

    A laboratory investigation of the vertical and lateral swelling pressures developed in statically compacted, air-dry specimens of sodium (Na)-bentonite:silica sand mixtures as they are saturated in confined conditions with double-distilled, deionized water is described. The results are interpreted with the aid of observations of the compacted soil structures made in a scanning electron microscope. It is shown that the sand acts as an inert filler material and vertical swelling pressures are controlled by a parameter termed the effective clay dry density (qsub(c)). A limiting value of qsub(c) exists below which vertical and lateral swelling pressures do not differ and are theoretically predictable. Above this value, vertical pressures exceed lateral ones. This is related to a change from an isotropic to an anisotropic soil fabric as qsub(c) is increased above the limiting value

  7. The use of light weight deflectometer for in situ evaluation of sand degree of compaction

    Directory of Open Access Journals (Sweden)

    Amr F. Elhakim

    2014-12-01

    Full Text Available The light weight deflectometer (LWD, also known as the light falling weight deflectometer, light drop weight tester, and dynamic plate load test, is a hand portable device that was developed in Germany to measure the soil in situ LWD dynamic modulus. Typically, this modulus is used to evaluate the subsoil degree of compaction. Thus it is suitable for compaction quality control of soil-surfaced roads, embankments and replacement fill. As a dynamic test, the device is suited, in particular, for coarse and mixed grained soils with a maximum grain size of 63 mm. The response of poorly graded calcareous and siliceous sands is the focus of this research. First, the index soil properties of the tested soils including grain size distribution; maximum and minimum void ratios and specific gravity were obtained. Petrographic analyses of the tested sands were also performed to determine their mineralogical composition. A 1-m3 chamber was built for performing the LWD testing in the laboratory. The study was performed for relative densities of 20%, 40%, 60% and 80% to represent the behavior of very loose, loose, medium dense and dense sands. The effect of the existence of a rigid boundary beneath the tested soil on test results was also investigated to determine the zone of influence of the light weight deflectometer.

  8. Retorting of bituminous sands

    Energy Technology Data Exchange (ETDEWEB)

    Chaney, P E; Ince, R W; Mason, C M

    1872-09-26

    This method of recovering oil from mined tar sands involves forming compacted tar sands pieces by special conditioning treatment that provides low internal permeability. The compacted pieces are then retorted in fixed bed form. The conditioning treatment can involve rolling of preformed pellets, compaction in a mold or pressure extrusion. Substantial collapsing of the bed during retorting is avoided. (9 claims) (Abstract only - original article not available from T.U.)

  9. 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.

  10. Comparative modelling of laboratory experiments for the hydro-mechanical behaviour of a compacted bentonite–sand\

    Czech Academy of Sciences Publication Activity Database

    Millard, A.; Mokni, N.; Barnichon, J. D.; Tatcher, K. E.; Bond, A.; Mc Dermott, C.; Blaheta, Radim; Michalec, Zdeněk; Hasal, Martin; Nguyen, T. S.; Nasir, O.; Fedors, S.; Yi, H.; Kolditz, O.

    2016-01-01

    Roč. 75, č. 20 (2016), s. 1311-1327 ISSN 1866-6280. [DECOVALEX 2015 /8./. Wakkanai, 13.10.2015-16.10.2015] Institutional support: RVO:68145535 Keywords : hydro-mechanical (hm) coupling * numerical modelling * sealing system s * compacted bentonite–sand mixture Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.569, year: 2016 http://link.springer.com/article/10.1007/s12665-016-6118-z

  11. 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...

  12. Laboratory investigation of the loading rate effects in sand

    NARCIS (Netherlands)

    Huy, N.Q.; Van Tol, A.F.; Hölscher, P.

    2006-01-01

    In order to improve the interpretation of the quasi-static (e.g. Statnamic) pile load tests, a research project has been started to investigate effects of the loading rate on the bearing capacity of a pile in sand. A series of laboratory tests has been carried out. The testing program consists of a

  13. The Influence of Baker Bay and Sand Island on Circulations in the Mouth of the Columbia River

    Science.gov (United States)

    2014-06-01

    Island is a good example of a dredge spoils area protected by a pile dike system. Without the stabilizing effect of the Sand Island pile dikes, the...Sand Island) and pile dikes, and the effects of these features on adjacent water masses in the lower Columbia River. 4 THIS PAGE INTENTIONALLY...each drifter using Velcro and nylon straps with pinch buckles. Each case contained a 1-Hz sampling internally-logging GT-31 handheld GPS unit for

  14. 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.

  15. Characteristics of SCC with Fly Ash and Manufactured Sand

    Science.gov (United States)

    Praveen Kumar, K.; Radhakrishna

    2016-09-01

    Self compacting concrete (SCC) of M40 grade was designed. The binder in SCC consists of OPC and fly ash in the ratio of 65:35. River sand was replaced by manufactured sand (M-sand) at replacement levels of 20,40,60,80 and 100%. An attempt was made to evaluate the workability and strength characteristics of self compacting concrete with river sand and manufactured sand as fine aggregates. For each replacement level, constant workability was maintained by varying the dosage of superplasticizer. T50 flow time, V Funnel time, V-funnel T5 time as well as compressive, split tensile and flexural strength of SCC were found at each replacement level of M-sand. They were compared to SCC with river sand. Results indicate favourable use of M-sand in preparation of Self Compacting Concrete.

  16. Rapid pile load tests in the geotechnical centrifuge

    NARCIS (Netherlands)

    Holscher, P.; Van Tol, A.F.; Huy, N.Q.

    2012-01-01

    Centrifiige experiments were carried out to gain insight into the factors that affect the mobilized resistance during rapid load testing on piles in sand. The influence of generated pore water pressure during rapid load tests is shidied, and its effect on the commonly used unloadmg point method to

  17. 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...

  18. Evaluation of automatic vacuum- assisted compaction solutions

    Directory of Open Access Journals (Sweden)

    M. Brzeziński

    2011-01-01

    Full Text Available Currently on the mould-making machines market the companies like: DiSA, KUENKEL WAGNER, HAFLINGER, HEINRICH WAGNER SINTO, HUNTER, SAVELLI AND TECHNICAL play significant role. These companies are the manufacturers of various solutions in machines and instalations applied in foundry engineering. Automatic foundry machines for compaction of green sand have the major role in mechanisation and automation processes of making the mould. The concept of operation of automatic machines is based on the static and dynamic methods of compacting the green sand. The method which gains the importance is the compacting method by using the energy of the air pressure. It's the initial stage or the supporting process of compacting the green sand. However in the automatic mould making machines using this method it's essential to use the additional compaction of the mass in order to receive the final parameters of the form. In the constructional solutions of the machines there is the additional division which concerns the method of putting the sand into the mould box. This division distinquishes the transport of the sand with simultaneous compaction or the putting of the sand without the pre-compaction. As the solutions of the major manufacturers are often the subject for application in various foundries, the authors of the paper would like/have the confidence to present their own evaluation process confirmed by their own researches and independent analysis of the producers' solutions.

  19. Cavity prediction in sand mould production applying the DISAMATIC process

    DEFF Research Database (Denmark)

    Hovad, Emil; Larsen, Per; Spangenberg, Jon

    2017-01-01

    The sand shot in the DISAMATIC process is simulated by the discrete element method (DEM) taking into account the influence and coupling of the airflow with computational fluid dynamics (CFD). The DEM model is calibrated by a ring shear test, a sand pile experiment and a slump test. Subsequently...

  20. Geophysics comes of age in oil sands development

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, P. [WorleyParsons Komex, Calgary, AB (Canada); Birch, R.; Parker, D.; Andrews, B. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics

    2008-07-01

    This paper discussed geophysical techniques developed for oil sands exploration and production applications in Alberta's oil sands region. Geophysical methods are playing an important role in mine planning, tailings containment, water supply, and land reclamation activities. Geophysics techniques are used to estimate the volume of muskeg that needs to be stripped and stored for future reclamation activities as well as to site muskeg piles and delineate the thickness of clay Clearwater formations overlying Cretaceous oil-bearing sands. 2-D electrical resistivity mapping is used to map river-connected deep bedrock Pleistocene paleovalleys in the region. Geophysical studies are also used to investigate the interiors of dikes and berms as well as to monitor salt migration within tailings piles. Sonic and density logs are used to create synthetic seismograms for mapping the Devonian surface in the region. The new applications included the calculation of bitumen saturation from surface sands and shales; muskeg thickness mapping; and non-intrusive monitoring of leachate plumes. Geophysical techniques included 2-D electrical resistivity imaging; transient electromagnetic (EM) technologies; ground penetrating radar; and high-resolution seismic reflections. Polarization, surface nuclear magnetic resonance and push-probe sensing techniques were also discussed. Techniques were discussed in relation to Alberta's Athabasca oil sands deposits. 4 refs.

  1. 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...

  2. 20051655 - Petronas, Capacity of Driven Piles Offshore Malaysia

    DEFF Research Database (Denmark)

    Augustesen, Anders

    This report presents the results of work carried out by Aalborg Univesity for NGI related to the effects of ageing on the axial capacity of piles in clay and sand. The document is the fourth of four notes regarding the subject and it includes a recommended approach to account for ageing effects f...

  3. bentonite-sand mixture as new backfill/buffer material

    International Nuclear Information System (INIS)

    Cui Suli; Liu Jisheng; Zhang Huyuan; Liang Jian

    2008-01-01

    The mixture of bentonite and quartz sand is suggested as a new backfill/buffer material for geological disposal of HLW. To improve the further design of underground laboratory and in-situ industrial construction test, the optimization of sand addition to bentonite is focused at present research stage. Based on summarizing the research results abroad, laboratory tests were conducted on the mixture of GMZ001 bentonite and quartz sand, such as compaction test and swelling tests etc. Test data shows that GMZ bentonite-sand mixture exhibits a favorite compaction with a 30% sand addition, a highest swelling pressure with a 20% sand addition, and a decreasing plasticity with increases in sand addition and pore liquid concentration. (authors)

  4. Drawer compacted sand filter: a new and innovative method for on-site grey water treatment.

    Science.gov (United States)

    Assayed, Almoayied; Chenoweth, Jonathan; Pedley, Steven

    2014-01-01

    In this paper, results ofa new sand filter design were presented. The drawer compacted sand filter (DCSF) is a modified design for a sand filter in which the sand layer is broken down into several layers, each of which is 10 cm high and placed in a movable drawer separated by a 10 cm space. A lab-scale DCSF was designed and operated for 330 days fed by synthetic grey water. The response of drawer sand filters to variable hydraulic and organic loading rates (HLR and OLR) in terms of biological oxygen demand (BODs), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity and Escherichia coli reductions were evaluated. The HLR was studied by increasing from 72 to 142 L m(-2) day(-1) and OLR was studied by increasing it from 23 to 30 g BOD5 m(-2) day(-1) while keeping the HLR constant at 142 L m(-2) day(-1). Each loading regime was applied for 110 days. Results showed that DCSF was able to remove >90% of organic matter and total suspended solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P water was drained through the third drawer in all tested loads. The paper concludes that DCSF would be appropriate for use in dense urban areas as its footprint is small and is appropriate for a wide range of users because of its convenience and low maintenance requirements.

  5. 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...

  6. Influence of loading rate on pile capacity in unsaturated sand

    NARCIS (Netherlands)

    Dijkstra, J.

    2004-01-01

    When in-situ tests are performed to determine the ultimate capacity of a pile after the installation, quite a lot of types of tests are available. The following tests are generally used, in order from most used method to least used method: the static testing method, dynamic testing methods,

  7. Survival and replication of Mycoplasma species in recycled bedding sand and association with mastitis on dairy farms in Utah.

    Science.gov (United States)

    Justice-Allen, A; Trujillo, J; Corbett, R; Harding, R; Goodell, G; Wilson, D

    2010-01-01

    Mycoplasma spp., usually Mycoplasma bovis, are important bovine pathogens that can cause mastitis, metritis, pneumonia, and arthritis. The currently documented routes of transmission of Mycoplasma spp. are through contaminated milking equipment and by direct animal contact. The existence of environmental sources for Mycoplasma spp. and their role in transmission and clinical disease is poorly characterized. Mycoplasma spp. (confirmed as M. bovis in 2 of 4 samples tested using PCR) was found in recycled bedding sand originating from a dairy experiencing an outbreak of clinical mycoplasma mastitis. Mycoplasma spp. were subsequently found in bedding sand from 2 other dairies whose bulk-tank milk was mycoplasma-positive. The association between the occurrence of Mycoplasma spp. in recycled bedding sand and mycoplasma mastitis in cows was further investigated using a pile of recycled sand from dairy 1. Study objectives included the determination of factors associated with the concentration of Mycoplasma spp. in recycled bedding sand and the duration of survival of mycoplasmas in the sand. We also evaluated the efficacy of 2 disinfectants at 2 different concentrations each for the elimination of Mycoplasma spp. from contaminated sand. Mycoplasma spp. survived in the sand pile for 8 mo. The concentration of Mycoplasma spp. within the sand pile was directly related to temperature and precipitation. It was also positively associated with the growth of gram-negative microorganisms, suggesting the possibility of the formation of a biofilm. Ideal temperatures for replication of Mycoplasma spp. occurred between 15 and 20 degrees C. Moisture in the sand and movement of the sand pile also appeared to play a role in replication of mycoplasmas. We found that 0.5% sodium hypochlorite or 2% chlorhexidine were efficacious in eliminating Mycoplasma spp. from contaminated bedding sand. Recycled bedding sand could be an environmental source of Mycoplasma spp., including M. bovis

  8. Alteration behavior of bentonite barrier of radioactive waste disposal by alkaline solutions. Part 2. Effect of type of alkaline solution on permeability of compacted bentonite-sand mixture

    International Nuclear Information System (INIS)

    Yokoyama, Shingo; Nakamura, Kunihiko; Tanaka, Yukihisa; Hironaga, Michihiko

    2011-01-01

    Permeability tests were carried out using compacted bentonite-sand mixture with initial dry density of 1.55 Mg/m 3 and alkaline solutions at 50degC for about two years to estimate the alteration behavior and the change in the permeability. Bentonite-sand mixtures which contain bentonites of 15wt% were made using Na-bentonite or Ca-exchanged bentonite. 0.3M-NaOH solution with pH 13.3 and 5mM-Ca(OH) 2 solution with pH 12.0 were used to the permeability tests of Na-bentonite-sand mixture and of Ca-exchanged bentonite-sand mixture, respectively. In the case of the permeability test conducted using NaOH solution, montmorillonite and other associated minerals were dissolved, and consequently, the dry density and effective montmorillonite density of Na-bentonite-sand mixture were decreased. Furthermore, the mineralogical feature of montmorillonite was changed (i.e. beidellitization and an increase in the layer charge). The permeability of Na-bentonite-sand mixture was increased 5.6 times by the end of permeability test as a result of above alteration. In the case of the permeability test conducted using Ca(OH) 2 solution, montmorillonite and other associated minerals were dissolved, and calcium silicate hydrate (C-S-H) was precipitated. Consequently, the dry density of Ca-exchanged bentonite-sand mixture was increased, while the effective montmorillonite density was decreased. The mineralogical feature of montmorillonite was changed (i.e. beidellitization and an increase in the layer charge). The permeability of Ca-exchange bentonite-sand mixture was decreased by more than two orders of magnitude due to fill the pore of Ca-exchange bentonite-sand mixture by the precipitation of C-S-H. From above results, the type of alkaline solution affects the mineralogical alteration behavior of the compacted bentonite-sand mixture, and consequently, affects the changing trend of permeability. In conclusion, it is important not only to consider the dissolution of montmorillonite, but

  9. 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

  10. 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

  11. Applicability of recycled aggregates in concrete piles for soft soil improvement.

    Science.gov (United States)

    Medeiros-Junior, Ronaldo A; Balestra, Carlos Et; Lima, Maryangela G

    2017-01-01

    The expressive generation of construction and demolition waste is stimulating several studies for reusing this material. The improvement of soft soils by concrete compaction piles has been widely applied for 40 years in some Brazilian cities. This technique is used to improve the bearing capacity of soft soils, allowing executing shallow foundations instead of deep foundations. The compaction piles use a high volume of material. This article explored the possibility of using recycled aggregates from construction waste to replace the natural aggregates in order to improve the bearing capacity of the soft soil, regarding its compressive strength. Construction wastes from different stages of a construction were used in order to make samples of concrete with recycled aggregates. The strength of concretes with natural aggregates was compared with the strength of concretes with recycled (fine and coarse) aggregates. Results show that all samples met the minimum compressive strength specified for compaction piles used to improve the bearing capacity of soft soils. The concrete with recycled aggregate from the structural stage had even higher resistances than the concrete with natural aggregates. This behaviour was attributed to the large amount of cementitious materials in the composition of this type of concrete. It was also observed that concrete with recycled fine aggregate has a superior resistance to concrete with recycled coarse aggregate.

  12. A mechanistic study of the uniform corrosion of copper in compacted clay-sand soil

    International Nuclear Information System (INIS)

    Litke, C.D.; Ryan, S.R.; King, F.

    1992-08-01

    The results of a study of the mechanism of uniform corrosion of copper under simulated nuclear fuel waste disposal conditions are presented. Evidence is given that suggests that the rate-controlling process is the transport of copper corrosion products away from the corroding surface. In the experiments described here, the copper diffused through a column of compacted clay-sand buffer. The properties of the buffer material, especially its ability to sorb copper species, are significant in determining the rate of uniform corrosion of copper. The evidence that copper diffusion is rate-controlling stems from the effect of γ-radiation on the tests. In the presence of γ-radiation, copper diffused farther along the column of compacted buffer material than in the unirradiated tests, but the corrosion rate was lower. These two effects can be best explained in terms of a slow copper-diffusion process. Irradiation is thought to reduce the extent of sorption of copper by the clay component of the buffer. This results in a more mobile copper species and a smaller interfacial flux of copper (i.e., a lower corrosion rate)

  13. Model Compaction Equation

    African Journals Online (AJOL)

    The currently proposed model compaction equation was derived from data sourced from the. Niger Delta and it relates porosity to depth for sandstones under hydrostatic pressure condition. The equation is useful in predicting porosity and compaction trend in hydrostatic sands of the. Niger Delta. GEOLOGICAL SETTING OF ...

  14. 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)

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. Development of the monitoring technique on the damage of piles using the biggest shaking table "E-defense"

    Science.gov (United States)

    Hayashi, Kazuhiro; Hachimori, Wataru; Kaneda, Shogo; Tamura, Shuji; Saito, Taiki

    2017-10-01

    In case of earthquake damage to buildings, the damage to a superstructure is visible, but the damage to a foundation structure, e.g. the underground pile, is difficult to detect. In this study, the authors aim to develop a monitoring technique for pile damage due to earthquakes. The world's biggest shaking table, E-Defense, was used to reproduce damage to RC pile models embedded in the soil inside a large scale shear box (8m in diameter and 6.5m in height). The diameter of the RC pile model was 154mm. It consisted of mortar (27.2N/mm2 in compressive strength), 6 main reinforcements (6.35mm in diameter) and shear reinforcement hard steel wire (2mm in diameter at intervals of 20mm). The natural period of the superstructure above the pile models is around 0.12sec. The soil consisted of 2 layers. The lower layer is Albany sand of 80% relative density while the upper layer is only 2m from the surface ground and is Kaketsu sand of 60% relative density. Primary four excitations were scaled from JMA Kobe waves in notification at different amplitudes. The maximum acceleration of each wave is 31gal, 67gal, 304gal, and 458gal, respectively. In the test result, reinforcing steels at the pile head of the RC model yielded when the maximum acceleration was 304gal. After that, mortar of the pile head peeled off and a bending shear failure occurred when the maximum acceleration was 458gal. The peak frequency of rotational spectrum on the foundation did not change in elastic range in the piles. However, the peak frequency fell after the plastic hinge occurred.

  1. 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....

  2. 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.

  3. Analytical Analysis and Field Test Investigation of Consolidation for CCSG Pile Composite Foundation in Soft Clay

    Directory of Open Access Journals (Sweden)

    Jin Yu

    2013-01-01

    Full Text Available Low-grade concrete-cored sand-gravel (CCSG pile composite foundation is a new kind of composite foundation for thick and soft clay ground treatment. An analytical solution was derived for calculating the consolidation process of this composite foundation by considering coefficients of horizontal permeability in smear zone, the radial flow within the sand-gravel shell, and the impervious property of concrete-cored pile. The results show that Terzaghi’s one-dimensional consolidation solution and the consolidation analytical solution of ordinary composite foundation were special cases of this solution. Curves of the average consolidation degree of the composite foundation under various nondimensional parameters were observed using the program based on the theoretical formula. Meanwhile, a series of in situ measurements including the settlement of pile and soil, the pore water pressure, and the total stress under embankment load were obtained on the CCSG pile composite foundation on a section of Zhenjiang-Liyang highway. The analyzed results show that the new style composite foundation patent technology has many advantages such as small differential postconstruction settlement (differential is not good, small is, reliable quality, high bearing capacity, and stability. And the consolidation of composite foundation is largely affected by the nondimensional parameters. The analytical solution is finally verified with the actual measurement data.

  4. Compaction and Collapse Characteristics of Dune Sand Stabilized with Lime-Silica Fume Mix

    Directory of Open Access Journals (Sweden)

    Mohammed Y. Fattah

    2016-04-01

    Full Text Available The purpose of this research is to assess the suitability of dune sands as construction materials. Moreover, such a goal is considered beneficial in determining appropriate methods for soil stabilization or ground improvement and to assessing the suitability of dune sands as subgrade layer for carrying roads and rail foundation. Dune sand samples were collected from a region in Baiji area in Salah-Aldeen governorate, North of Iraq. A grey-colored densified silica fume (SF and lime (L are used. Three percentages are used for lime (3%, 6%, and 9%, and four rates are used for silica fume (3%, 6%, 9% and 12% and the maximum percentage of silica fume is mixed with the proportions of lime. Unsoaked California Bearing Ratio (CBR on compacted dune sands treated dune sands with L-SF by mixing and cured for one day. The increasing in CBR ranged between 443 – 707% at 2.54 mm penetration and 345 – 410% at 5.08 mm penetration.     Resumen El propósito de esta investigación es evaluar el uso de arena de dunas como materiales de construcción. Además, este objetivo permite determinar los métodos apropiados para la estabilización del suelo, el mejoramiento del terreno y la evaluación de pertinencia de la arena de dunas en capas subbase para carreteras y cimientos férreos. Se recolectaron muestras de arena de dunas en el área de Baiji, del comisionado Salah-Aldeen, al norte de Irak. Se utilizó vapor de óxido de silicio (SF, en inglés, grisáceo y densificado, y óxido de calcio (L. Se utilizaron tres porcentajes para el óxido de calcio (3 %, 6 % y 9 %, y cuatro para el óxido de silicio (3 %, 6 %,  9% y 12% y el máximo porcentaje del óxido de silicio se mezcló con las proporciones de óxido de calcio. Se realizó en seco el Ensayo de Relación de Soporte de California (del inglés California Bearing Ratio, CBR en arena de dunas compactada y tratada con la mezcla L-SF curada durante un día. El incremento en el ensayo CBR osciló entre 443

  5. Analytical Model for the End-Bearing Capacity of Tapered Piles Using Cavity Expansion Theory

    Directory of Open Access Journals (Sweden)

    Suman Manandhar

    2012-01-01

    Full Text Available On the basis of evidence from model tests on increasing the end-bearing behavior of tapered piles at the load-settlement curve, this paper proposes an analytical spherical cavity expansion theory to evaluate the end-bearing capacity. The angle of tapering is inserted in the proposed model to evaluate the end-bearing capacity. The test results of the proposed model in different types of sands and different relative densities show good effects compared to conventional straight piles. The end-bearing capacity increases with increases in the tapering angle. The paper then propounds a model for prototypes and real-type pile tests which predicts and validates to evaluate the end-bearing capacity.

  6. Design Analysis and Observed Performance of a Tieback Anchored Pile Wall in Sand

    Directory of Open Access Journals (Sweden)

    Jian-Yong Han

    2017-01-01

    Full Text Available This paper aims to study the design process and service performance of a deep excavation supported by tieback anchored pile walls. The design procedure and design approaches for deep excavation in China are described. Based on the excavation case history for Shenyang, China, design results obtained using the elastic method and the finite element method (FEM are compared and analyzed. Special emphasis is given to the analysis of horizontal wall deformations, internal forces in the wall, earth pressures on the wall, ground surface settlements, and stabilities of the excavation. The similarities and differences between the Chinese code (JGJ 120-2012 and the European code (EN 1997-1 for the design of geotechnical structures are presented based on a design example. Through the comparison, it is indicated that the Chinese code focuses on the design result, while the European code focuses on the design process. The crucial construction methods for reducing construction risk based on the excavation case history are described. The mechanical behaviors of the excavation retained by an anchored pile wall were investigated by analyzing observed field cases. The results provide good, practical guidelines for the design and construction of a tieback anchored pile wall retained excavation in sandy soil.

  7. 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…

  8. 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%.

  9. Ultimate Lateral Capacity of Rigid Pile in c- φ Soil

    Science.gov (United States)

    Zhang, Wei-min

    2018-03-01

    To date no analytical solution of the pile ultimate lateral capacity for the general c- φ soil has been obtained. In the present study, a new dimensionless embedded ratio was proposed and the analytical solutions of ultimate lateral capacity and rotation center of rigid pile in c- φ soils were obtained. The results showed that both the dimensionless ultimate lateral capacity and dimensionless rotation center were the univariate functions of the embedded ratio. Also, the ultimate lateral capacity in the c- φ soil was the combination of the ultimate lateral capacity ( f c ) in the clay, and the ultimate lateral capacity ( f φ ) in the sand. Therefore, the Broms chart for clay, solution for clay ( φ=0) put forward by Poulos and Davis, solution for sand ( c=0) obtained by Petrasovits and Awad, and Kondner's ultimate bending moment were all proven to be the special cases of the general solution in the present study. A comparison of the field and laboratory tests in 93 cases showed that the average ratios of the theoretical values to the experimental value ranged from 0.85 to 1.15. Also, the theoretical values displayed a good agreement with the test values.

  10. Neural networks and principle component analysis approaches to predict pile capacity in sand

    Directory of Open Access Journals (Sweden)

    Benali A

    2018-01-01

    Full Text Available Determination of pile bearing capacity from the in-situ tests has developed considerably due to the significant development of their technology. The project presented in this paper is a combination of two approaches, artificial neural networks and main component analyses that allow the development of a neural network model that provides a more accurate prediction of axial load bearing capacity based on the SPT test data. The retropropagation multi-layer perceptron with Bayesian regularization (RB was used in this model. This was established by the incorporation of about 260 data, obtained from the published literature, of experimental programs for large displacement driven piles. The PCA method is proposed for compression and suppression of the correlation between these data. This will improve the performance of generalization of the model.

  11. 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)

  12. Geotechnical properties of crude oil contaminated sand

    International Nuclear Information System (INIS)

    Puri, V.K.; Das, B.M.; Cook, E.E.; Shin, E.C.

    1994-01-01

    Contamination of soil due to an oil spill influences its subsequent engineering behavior. An investigation was conducted to study the effect of crude oil contamination on compaction characteristics, shear strength, one-dimensional compression, and coefficient of permeability. Water permeability was also determined by using commercial grade motor oils as contaminants. The test results indicate that the compaction characteristics are influenced by oil contamination. The angle of internal friction of sand (based on total stress condition) decreases due to presence of oil within the pore spaces in sand. One dimensional compression characteristics of sand are significantly influenced by oil contamination resulting in a decrease in the value of constrained modulus with increase in the degree of oil contamination compared to the case of dry sand. Water permeability was observed to be a function of the initial viscosity and the degree of saturation due to the contaminating oil

  13. Evaluation of Small-Scale Laterally Loaded Monopiles in Sand

    DEFF Research Database (Denmark)

    Roesen, Hanne Ravn; Thomassen, Kristina; Sørensen, Søren Peder Hyldal

    2011-01-01

    In current designs of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopoles when subjected to lateral loading has not been fully investigated. In this paper the diameter effect on laterally loaded non-slender piles in sand is evaluated by means of results ...

  14. Experimental Comparison of Non-Slender Piles under Static Loading and under Cyclic Loading in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Ibsen, Lars Bo

    2012-01-01

    An experimental evaluation of the pile behavior of non-slender piles exposed to static and cyclic lateral loading is presented. The tests were conducted in a pressure tank at Aalborg University. This enabled the possibility of applying an overburden pressure to the soil. When conducting small......-scale tests at 1-g the determination of the friction angle and the Young’s modulus of elasticity of the soil are difficult and further these soil parameters varies greatly with depth. These uncertainties were avoided by application of an overburden pressure....

  15. 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)

  16. 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)

  17. A Snapshot of Present Research at AAU and DTU on Large-Diameter Piles in Coarse-Grained Materials

    DEFF Research Database (Denmark)

    Leth, C. T.; Sørensen, Søren Peder Hyldal; Klinkvort, Rasmus Tofte

    2012-01-01

    are developed for piles with diameters up to approximately 2.0 m and are based on a very limited number of tests. Hence, the method has not been validated for piles with diameters of 4 to 6 m. During the last six years extensive studies on non-slender large-diameter piles in coarse-grained material have been...... conducted at Aalborg University (AAU) and at the Technical University of Denmark (DTU). The piles have been investigated by means of physical and numerical modelling. The former consists of both centrifuge tests and tests in a so-called pressure tank (1G tests but with an applied overburden pressure......). The goal of the work has been to investigate the general behaviour of monopiles for nowadays offshore wind turbines and to revise the p-y curves for piles in sand in order to account for diameter on the response of monopiles subjected to both static and cyclic loads. The paper summarizes and compares...

  18. 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

  19. 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.

  20. 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.

  1. Failure behavior of concrete pile and super-structure dynamic response as a result of soil liquefaction during earthquake

    Science.gov (United States)

    Kaneda, Shogo; Hayashi, Kazuhiro; Hachimori, Wataru; Tamura, Shuji; Saito, Taiki

    2017-10-01

    In past earthquake disasters, numerous building structure piles were damaged by soil liquefaction occurring during the earthquake. Damage to these piles, because they are underground, is difficult to find. The authors aim to develop a monitoring method of pile damage based on superstructure dynamic response. This paper investigated the relationship between the damage of large cross section cementitious piles and the dynamic response of the super structure using a centrifuge test apparatus. A dynamic specimen used simple cross section pile models consisting of aluminum rod and mortar, a saturated soil (Toyoura sand) of a relative density of 40% and a super structure model of a natural period of 0.63sec. In the shaking table test under a 50G field (length scale of 1/50), excitation was a total of 3 motions scaled from the Rinkai wave at different amplitudes. The maximum acceleration of each of the excitations was 602gal, 336gal and 299gal. The centrifuge test demonstrated the liquefaction of saturated soil and the failure behavior of piles. In the test result, the damage of piles affected the predominant period of acceleration response spectrum on the footing of the superstructure.

  2. Comparison of static and high strain dynamic tests on driven steel piles at several industrial sites in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Tweedie, R.; Clementino, R.; Law, D. [Thurber Engineering Ltd., Edmonton, AB (Canada)

    2009-07-01

    Many of the foundations at industrial plants in northern Alberta are supported by driven steel piles that are often installed through thick glacial clay and sand deposits. This paper presented 3 case histories where static load tests (SLT) and high strain dynamic tests (HSDT) were conducted on the driven steel piles. The soil conditions and typical pile sizes used at the 3 sites were described. The first site was an oilsand processing facility where steam assisted gravity drainage (SAGD) was used for bitumen production from oilsand. The second site was a petrochemical plant and the third site was a power plant. The case histories revealed the importance of combining SLT and HSDT to optimize pile designs. The paper emphasized the benefits of undertaking the pile load tests during the design phase, when the potential benefits of obtaining higher capacities can be effectively applied to the pile designs. It was concluded that pile design based on Limit States Design (LSD) in accordance with NBC 2005 must satisfy the Ultimate Limit States (ULS) to prevent plunging failure and also Serviceability Limit States (SLS) to maintain tolerable settlement. 10 refs., 5 tabs., 7 figs.

  3. Small-Scale Testing of Laterally Loaded Non-Slender Monopiles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Roesen, Hanne Ravn; Ibsen, Lars Bo

    in sand subjected to lateral loading are analysed by means of small-scale laboratory tests. The six quasi-static tests are conducted on piles with diameters of 40 mm and 100 mm and a slenderness ratio, L/D, of 5. In order to minimise scale effects, the tests are carried out in a pressure tank at stress...... levels of 0 kPa, 50 kPa, and 100 kPa, respectively. From the tests load-deflection relationships of the piles at three levels above the soil surface are obtained. The load-deflection relationships reveal that the uncertainties of the results for the pile with diameter of 40~mm are large due to the small......In current design of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopiles when subjected to lateral loading has not been fully investigated, e.g. the diameter effect on the soil response. In this paper the behaviour of two non-slender aluminium piles...

  4. Rate type isotach compaction of consolidated sandstone

    NARCIS (Netherlands)

    Waal, J.A. de; Thienen-Visser, K. van; Pruiksma, J.P.

    2015-01-01

    Laboratory experiments on samples from a consolidated sandstone reservoir are presented that demonstrate rate type compaction behaviour similar to that observed on unconsolidated sands and soils. Such rate type behaviour can have large consequences for reservoir compaction, surface subsidence and

  5. 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.)

  6. Response of monopiles under cyclic lateral loading in sand

    DEFF Research Database (Denmark)

    Nicolai, Giulio; Ibsen, Lars Bo

    2015-01-01

    Currently the main design guidelines propose to reduce the lateral resistance of offshore piles when accounting for cyclic loading. The present work provides results from laboratory tests in which such reduction has not occurred. The experimental investigation is based on testing a small......-scale monopile model in dense saturated sand. The experimental setup used to carry out the laboratory tests is able to apply thousands of load cycles and static loading to the monopile model. The purpose of the laboratory tests is to investigate the effects of cyclic loading on the lateral resistance...... of the monopile. It is shown that the soil-pile system becomes stiffer and more resistant after applying cyclic loading, depending on the number of cycles....

  7. Small-Scale Testing of Laterally Loaded Monopiles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Roesen, Hanne Ravn; Ibsen, Lars Bo

    2011-01-01

    of small-scale laboratory tests. Six quasi-static tests are conducted on piles with diameters of 40mm and 100mm and a slenderness ratio, L/D, of 5. To minimise scale effects, the tests are carried out in a pressure tank at various stress levels. From the obtained load-deflection relationships......In current designs of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopoles when subjected to lateral loading has not been fully investigated. In this paper, the behaviour of two non-slender piles in sand subjected to lateral loading are analysed by means...... it is revealed that the uncertainties of the results for the pile with a diameter of 40mm are large. The load-deflection relationships normalised as H/(L2Dγ’) and y/D indicate that the lateral load, H, is proportional to L2D. Comparison of the normalised load-deflection relationships for different stress levels...

  8. Effect of slash on forwarder soil compaction

    Science.gov (United States)

    Timothy P. McDonald; Fernando Seixas

    1997-01-01

    A study of the effect of slash on forwarder soil compaction was carried out. The level of soil compaction at two soil moisture contents, three slash densities (0, 10, and 20 kg/m2), and two levels of traffic (one and five passes) were measured. Results indicated that, on dry, loamy sand soils, the presence of slash did not decrease soil compaction after one forwarder...

  9. 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.

  10. 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.)

  11. 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.

  12. 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.

  13. 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...

  14. Hydraulic fracture considerations in oil sand overburden dams

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R.; Madden, B.; Danku, M. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

    2008-07-01

    This paper discussed hydraulic fracture potential in the dry-filled temporary dams used in the oil sands industry. Hydraulic fractures can occur when reservoir fluid pressures are greater than the minimum stresses in a dam. Stress and strain conditions are influenced by pore pressures, levels of compaction in adjacent fills as well as by underlying pit floor and abutment conditions. Propagation pressure and crack initiation pressures must also be considered in order to provide improved hydraulic fracture protection to dams. Hydraulic fractures typically result in piping failures. Three cases of hydraulic fracture at oil sands operations in Alberta were presented. The study showed that hydraulic fracture failure modes must be considered in dam designs, particularly when thin compacted lift of dry fill are used to replace wetted clay cores. The risk of hydraulic fractures can be reduced by eliminating in situ bedrock irregularities and abutments. Overpressure heights, abutment sloping, and the sloping of fills above abutments, as well as the dam's width and base conditions must also be considered in relation to potential hydraulic fractures. It was concluded that upstream sand beaches and internal filters can help to prevent hydraulic fractures in dams in compacted control zones. 5 refs., 16 figs.

  15. Final report on Thermally Modified Sand demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-23

    The use of salt and salt/sand mixtures on icy roadway surfaces has dramatically increased during the past 30 years. Despite extensive documentation on salt related damage to the roadway improvements, vehicles and the environment, road maintenance departments have continued to rely on this practice. Road maintenance departments in northern climate areas have long recognized the safety benefits for public mobility on icy roadways from the use of sand. As an abrasive material, the sand improves the surface traction that results in more drivable and less hazardous road conditions during the winter months. Stockpiles of pure sand stored during the winter months oftentimes freeze into large unworkable, monolithic piles. To maintain a free-flowing condition, it has been found to be necessary to add salt to the sand. The addition of salt in amounts ranging from 5 to 10 percent to that of sand, is usually sufficient to provide relatively free-flowing abrasive material that could be stored in stockpiles and applied to icy road surfaces with conventional sand spreading trucks. Another alternative for winter storage of pure sand to maintain a free-flowing condition is in humidity-controlled, heated buildings. As would be expected, this method has high capital and operating costs. and not cost effective for general highway maintenance use. The invention demonstrated herein is a method of thermally modifying pure sand that will remain in a free-flowing state throughout the winter season without the need for the salt additive. The thermally modified sand provides an abrasive material that when applied to icy roads does not cause environmental and corrosive damage as done by the application of sand with salt. By employing a very simple process of freezing screened sand particles by forced air convection under subfreezing conditions, the invention creates a product that has significant value in terms of economic and environmental benefits.

  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. 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.

  18. A Numerical Investigation on the Effect of Gas Pressure on the Water Saturation of Compacted Bentonite-Sand Samples

    Directory of Open Access Journals (Sweden)

    Jiang-Feng Liu

    2017-01-01

    Full Text Available In deep geological disposal for high-level radioactive waste, the generated gas can potentially affect the sealing ability of bentonite buffers. There is a competition between water and gas: the former provides sealing by swelling bentonite, and the latter attempts to desaturate the bentonite buffer. Thus, this study focused on numerically modelling the coupling effects of water and gas on the water saturation and sealing efficiency of compacted bentonite-sand samples. Different gas pressures were applied to the top surface of an upper sample, whereas the water pressure on the bottom side of the lower sample was maintained at 4 MPa. The results indicated that gas pressure did not significantly affect the saturation of the bentonite-sand sample until 2 MPa. At 2 MPa, the degree of water saturation of the upper sample was close to 1.0. As the gas pressure increased, this influence was more apparent. When the gas pressure was 6 MPa or higher, it was difficult for the upper sample to become fully saturated. Additionally, the lower sample was desaturated due to the high gas pressure. This indicated that gas pressure played an important role in the water saturation process and can affect the sealing efficiency of bentonite-based buffer materials.

  19. 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...

  20. Environmentally Friendly Solution to Ground Hazards in Design of Bridges in Earthquake Prone Areas Using Timber Piles

    Science.gov (United States)

    Sadeghi, H.

    2015-12-01

    Bridges are major elements of infrastructure in all societies. Their safety and continued serviceability guaranties the transportation and emergency access in urban and rural areas. However, these important structures are subject to earthquake induced damages in structure and foundations. The basic approach to the proper support of foundations are a) distribution of imposed loads to foundation in a way they can resist those loads without excessive settlement and failure; b) modification of foundation ground with various available methods; and c) combination of "a" and "b". The engineers has to face the task of designing the foundations meeting all safely and serviceability criteria but sometimes when there are numerous environmental and financial constrains, the use of some traditional methods become inevitable. This paper explains the application of timber piles to improve ground resistance to liquefaction and to secure the abutments of short to medium length bridges in an earthquake/liquefaction prone area in Bohol Island, Philippines. The limitations of using the common ground improvement methods (i.e., injection, dynamic compaction) because of either environmental or financial concerns along with the abundance of timber in the area made the engineers to use a network of timber piles behind the backwalls of the bridge abutments. The suggested timber pile network is simulated by numerical methods and its safety is examined. The results show that the compaction caused by driving of the piles and bearing capacity provided by timbers reduce the settlement and lateral movements due to service and earthquake induced loads.

  1. 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)

  2. Deep Compaction Control of Sandy Soils

    Directory of Open Access Journals (Sweden)

    Bałachowski Lech

    2015-02-01

    Full Text Available Vibroflotation, vibratory compaction, micro-blasting or heavy tamping are typical improvement methods for the cohesionless deposits of high thickness. The complex mechanism of deep soil compaction is related to void ratio decrease with grain rearrangements, lateral stress increase, prestressing effect of certain number of load cycles, water pressure dissipation, aging and other effects. Calibration chamber based interpretation of CPTU/DMT can be used to take into account vertical and horizontal stress and void ratio effects. Some examples of interpretation of soundings in pre-treated and compacted sands are given. Some acceptance criteria for compaction control are discussed. The improvement factors are analysed including the normalised approach based on the soil behaviour type index.

  3. Effect of Rigidity of Plinth Beam on Soil Interaction of Modeled Building Frame Supported on Pile Groups

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Reddy, C.

    2014-01-01

    Full Text Available This paper presents the effect of rigidity of plinth beam on a model building frame supported by pile groups embedded in cohesionless soil (sand through the results of static vertical load tests. The effect of rigidity of plinth beam on displacements and rotation at the column base and also shears and bending moments in the building frame were investigated. In the analytical model, soil nonlinearity in the axial direction is characterized by nonlinear vertical springs along the length of the pile (t-z curves and at the tip of the pile (Q-z curves while in the lateral direction by the p-y curves. Results revealed that, shear force and bending moment values which were back calculated from the experimental results, showed considerable reduction with the reduction of the rigidity of the plinth beam. The response of the frame from the experimental results is in good agreement with that obtained by the nonlinear finite element analysis.

  4. Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS).

    OpenAIRE

    Mareike Noah; Andrea Vieth-Hillebrand; Heinz Wilkes

    2012-01-01

    The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying sus...

  5. 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...

  6. Influence factors of sand-bentonite mixtures on hydraulic conductivity

    International Nuclear Information System (INIS)

    Chen Yonggui; Ye Weimin; Chen Bao; Wan Min; Wang Qiong

    2008-01-01

    Buffer material is a very important part of the engineering barrier for geological disposal of high-level radioactive nuclear waste. Compacted bentonite is attracting greater attention as buffer and backfill material because it offer impermeability and swelling properties, but the pure compacted bentonite strength decreases with increasing hydration and these will reduce the buffer capability. To solve this problem, sand is often used to form compacted sand-bentonite mixtures (SBMs) providing high thermal conductivity, excellent compaction capacity, long-time stability, and low engineering cost. As to SBMs, hydraulic conductivity is a important index for evaluation barrier capability. Based on the review of research results, the factors affecting the hydraulic conductivity of SBMs were put forward including bentonite content, grain size distribution, moisture content, dry density, compacting method and energy, and bentonite type. The studies show that the hydraulic conductivity of SBMs is controlled by the hydraulic conductivity of the bentonite, it also decreases as dry density and bentonite content increase, but when the bentonite content reach a critical point, the influence of increasing bentonite to decrease the hydraulic conductivity is limited. A fine and well-graded SBMs is likely to have a lower hydraulic conductivity than a coarse and poorly graded material. The internal erosion or erodibility based on the grain size distribution of the SBMs has a negative effect on the final hydraulic conductivity. The lowest hydraulic conductivity is gained when the mixtures are compacted close to optimum moisture content. Also, the mixtures compacted at moisture contents slightly above optimum values give lower hydraulic conductivity than when compacted at slightly under the optimum moisture content. Finally, discussion was brought to importance of compaction method, compacting energy, and bentonite type to the hydraulic conductivity of SBMs. (authors)

  7. MODERN METHODS OF DESIGN AND ARRANGEMENT OF RAMMING PILES IN PUNCHED HOLES

    Directory of Open Access Journals (Sweden)

    ZOTSENKO N. L.

    2015-10-01

    Full Text Available Problem statement. Ramming piles in punched holes (RPPH differ of high degree of use of supporting capacity of base because of forming in it a compacted zone at the expense of displacement of soil in the volume rammer and compacted material of expansion. The method of their construction almost exclude excavation and formwork, reducing the consumption of concrete, metal, accelerates zero cycle compared to the foundations raised and excavation and immersion into the soil of precast elements. The expansion of the normative base, their design and construction should be for further implementation of of natural objects. The correctness of the geomechanical model of plane and spatial version of finite element method (FEM should be proved for the calculation of cooperative work of RPPH as part of grillages with base. The most effective kinds of equipment and technological schemes of construction of RPPH should be noticed. Conclusions. The paper presents the main regulations on the design and the arrangement RPPH, corresponding of construction norms of Ukraine. The results of experimental and theoretical studies conducted by the authors for over thirty years, and the experience of the use of these piles on the objects of civil engineering, industrial and agricultural construction made their base. The use of the elastoplastic model with the criterion of Mohr-Coulomb strength for designing of the system "grillage -RPPH- soil" was substantiated. The designing in plane and spatial problems of FEM is proved that in the distance between the axes of adjacent piles up to five diameters is a correct choice of a flat version and simplifying of calculating scheme to the conventional strip foundation. An improved. The method of calculating of RPPH as part of grillages ribbon, where as the width of the foundation was taken a diameter of the broadening of the pile, and the depth of its inception corresponds to the bottom of it. The supporting layer of base under the

  8. MORPHOMETRIC CHARACTERIZATION OF THE SAND FRACTION IN A SAND GRAIN IMAGE CAPTURE SYSTEM1

    Directory of Open Access Journals (Sweden)

    Lucimar Arruda Viana

    Full Text Available ABSTRACT Morphology studies assume significant importance in analysis of phenomena of granular systems packaging, in particular with a view to the use of the technique of soil stabilization named particle size correction in forest roads. In this context, this study aimed to develop and operationalize a Sand Grain Image Capture System and, hereby, determine the morphological indices of the sand fractions of two sandy soils called João Pinheiro (JP and Cachoeira da Prata (CP. Soil samples, air-dried, were sieved (2.0 mm nominal mesh size for removal of gravels. The materials that passed through the sieve were subjected to dispersion, washing in 0.053 mm nominal mesh size sieve, removal of organic matter and iron oxides to obtain the clean sand fractions. Subsequently, each soil sample was sieved for separation into twelve classes, between the diameters of 0.149 mm and 1.190 mm, using a Rotap shaker. Next, tests were carried out to characterize the morphometric attributes of the twelve classes of sand fractions of the soils studied. For validation of the performance of the Sand Grain Image Capture System, the results were compared to those obtained using a standard procedure for image analysis. The analysis of the results led to the following conclusions: (i the sand fraction of the JP soil presented higher values for the morphometric indices roundness, elongation and compactness compared to sand fraction of the CP soil; and (ii the Sand Grain Image Capture System worked properly, with practicality.

  9. 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 

  10. Aging effects on oil-contaminated Kuwaiti sand

    International Nuclear Information System (INIS)

    Al-Sanad, H.A.; Ismael, N.F.

    1997-01-01

    Large quantities of oil-contaminated sands resulted from the destruction of oil wells and the formation of oil lakes in Kuwait at the end of the Gulf Wa/r. A laboratory testing program was carried out to determine the geotechnical properties of this material and the effect of aging on their properties. Tests included direct shear, triaxial, and consolidation tests on clean and contaminated sand at the same relative density. The influence of aging was examined by testing uncontaminated sand after aging for one, three, and six months in natural environmental conditions. The results indicated increased strength and stiffness due to aging and a reduction of the oil content due to evaporation of volatile compounds. The factors that influence the depth of oil penetration in compacted sand columns were also examined including the type of oil, relative density, and the amount of fines

  11. Elastoplastic constitutive models parameters for unsaturated compacted bentonite sand buffer (BSB)

    International Nuclear Information System (INIS)

    Priyanto, D.; Man, A.; Dixon, D.; Blatz, J.

    2010-01-01

    Document available in extended abstract form only. Compacted Bentonite-Sand Buffer (BSB) material is one of the clay based sealing-system components proposed for use in a Canadian Deep Geological Repository (DGR) for used nuclear fuel. BSB is a 50:50 mixture (by dry mass) of bentonite and well-graded silica sand, compacted to a dry density of at least 1.67 Mg/m 3 . Numerical modelling of the evolution of a DGR requires defining of the Hydro-Mechanical (HM) parameters of the BSB. The objective of this paper is to determine the parameters that are needed to utilize an elastoplastic model to describe the BSB. The parameters of the Basic Barcelona Model (BBM) for BSB are determined based on the results of laboratory tests done under both water-saturated and unsaturated conditions. The BBM utilizes three key stress-state variables: net mean stress (p), deviatoric stress (q), and suction (s). Modification of the BBM to improve the prediction of the BSB behaviour is made based on these laboratory test results. Pre-consolidation stress (p o ), stiffness parameters due to changes in p in elastic (?) and plastic (λ(s)) ranges are determined from triaxial test results under isotropic loading, unloading and constant mass conditions with suctions in the range of 0-125 MPa. An increase of s results in an increase of p o and a decrease of λ(s) for s < 30 MPa, and constant po and λ(s) for s > 30 MPa. These data are used to determine the LC-Line. Blatz (2000) and Anderson (2003) concluded that the BSB has clay-dominated behaviour for s < 30 MPa and sand-dominated behaviour for s > 30 MPa. Based on this conclusion, the hardening parameter so of the suction increase yield curve is equal to 30 MPa. Using a measured s-v relationship from shrinkage tests, stiffness parameters for changes in s in the elastic range (?s) are approximately ∼ 0.065 and in the plastic range (λs) are approximately ∼ 0, which is different from the original BBM featuring λs > ?s. The tensile strength

  12. 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

  13. 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

  14. 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)

  15. Laterally cyclic loading of monopile in dense sand

    DEFF Research Database (Denmark)

    Klinkvort, Rasmus Tofte; Hededal, Ole; Svensson, M.

    2011-01-01

    In order to investigate the response from laterally cyclic loading of monopiles a large centrifuge tests series is ongoing at the Technical University of Denmark (DTU). This paper will present some of the tests carried out with a focus on the influence of accumulation of rotation when changing...... the loading conditions. In these tests the load conditions are controlled by two load characteristics, one controlling the level of the cyclic loading and one controlling the characteristic of the cyclic loading. The centrifuge tests were performed in dense dry sand on a pile with prototype dimensions...

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. Study on strength estimation of soil cement used in the embedded pile method by electrical resistivity measurement

    Science.gov (United States)

    Mochida, Y.; Sakurai, Y.; Indra, H.; Karimi, A. L.

    2017-11-01

    Problems caused by poor quality control and quality assurance of the pre-boring embedded pile construction, such as on domestic apartment house is still occurring nowadays. An adequate consideration for invisible risks inside or below the ground is important in pile foundation construction therefore the demand for advanced and reliable quality assurance is increase in the future. In this research, to understand the quality of the construction at early stage, the compressive strength of cement-soil mixture of pile construction after 28 days is estimated using electrical resistivity value of the mixture. More accurate measurement for electrical resistivity value is conducted by inserting the electrodes without using potassium chloride solution as a catalyst. The result showed that there is a certain tendency in the electric resistivity value at the early age regarding to the type of soil (sand, clay) mixed in. The most accurate estimation was achieved from the electric resistivity value at the first day and several days onwards, and from the compressive strength after 3 days.

  4. Investigation of guided waves propagation in pipe buried in sand

    International Nuclear Information System (INIS)

    Leinov, Eli; Cawley, Peter; Lowe, Michael J.S.

    2014-01-01

    The inspection of pipelines by guided wave testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the waves caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the propagation and attenuation characteristics of guided waves in pipes buried in fine sand using a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided waves are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of wave behavior in the buried pipe. We present the methodology and the systematic measurements of the guided waves under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided waves in buried pipes with a high level of confidence

  5. 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

  6. Effect of soil compactness on the growth and quality of carrot

    Directory of Open Access Journals (Sweden)

    Liisa Pietola

    1995-05-01

    Full Text Available Field experiments were performed in Southern Finland on three soil types: fine sand (1989-1991, clay (1989 and mull (1990-1991. The following soil mechanical treatments were applied to autumn ploughed land: soil loosening by ridge preparation (ridge distance 45 cm, rotary harrowing (to a depth of 20 cm, clay 15 cm, and soil compaction track by track by a tractor weighing 3 Mg (1 or 3 passes, wheel width 33 cm before seed bed preparation. One plot was untreated. These treatments were set up in April (on clay in May under moist soil conditions. Sprinkler irrigation (one application of 30 mm was applied to clay and fine sand when soil moisture in top soil had decreased to around 50% of plant-available water capacity. PVC cylinders (r = 15 cm, h = 60 cm were fixed in the experimental areas during the growing periods. At harvest, these cylinders were removed for specific analysis of tap and fibrous roots of carrot. Length and width of fibrous roots were quantified by image analysis in the USA. The impacts of soil loosening and partial compaction were determined by measuring soil physical parameters to a depth of 25 cm in mineral soils, and to greater depths in organic soil. Dry bulk densities of the plough layers increased with increasing tractor passes by 8%, 10% and 13% for fine sand, mull and clay soils, respectively. The lowest dry soil bulk density in the plough layer was obtained by rotary harrowing to a depth of 20 cm. Comparison of gamma ray transmission and gravimetric analysis indicated that dry soil bulk density was slightly lower when determined by gravimetric analysis. Increased soil bulk densities were reflected by increased water retention capacity (matric suction ≤ 10 kPa and greater penetrometer resistance. Relatively similar increases in bulk density increased the penetrometer resistance much less in mull than in fine sand. In contrast, greater bulk densities in the mull soil affected soil air composition adversely by decreasing

  7. 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

  8. 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.

  9. 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

  10. 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...

  11. 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...

  12. HIGH-QUALITY SELF-COMPACTING CONCRETE WITH COAL BURNING WASTE

    Directory of Open Access Journals (Sweden)

    Voronin Viktor Valerianovich

    2018-01-01

    Full Text Available Subject: nowadays self-compacting concretes (SCC, the use of which requires no additional compaction, have become widespread for use in densely-reinforced structures and hard-to-reach places. In self-compacting concretes, finely-ground admixtures-microfillers are widely used for controlling technological properties. Their introduction into the concrete mix allows us to obtain more dense structure of concrete. The influence of micro-fillers on water consumption and plasticity of concrete mix, on kinetics of strength gain rate, heat release and corrosion resistance is also noticeable. Research objectives: the work focuses on the development of composition of self-compacting concrete with assigned properties with the use of fly ash based on coal burning waste, optimized with the help of experimental design method in order to clarify the influence of ash and cement quantity, sand size on strength properties. Materials and methods: pure Portland cement CEM I 42.5 N was used as a binder. Crushed granite of fraction 5…20 mm was used as coarse aggregate, coarse quartz sand with the fineness modulus of 2.6 and fine sand with the fineness modulus of 1.4 were used as fillers. A superplasticizer BASF-Master Glenium 115 was used as a plasticizing admixture. The fly ash from Cherepetskaya thermal power plant was used as a filler. The study of strength and technological properties of self-compacting concrete was performed by using standard methods. Results: we obtained three-factor quadratic dependence of strength properties on the content of ash, cement and fraction of fine filler in the mix of fine fillers. Conclusions: introduction of micro-filler admixture based on the fly ash allowed us to obtain a concrete mix with high mobility, fluidity and self-compaction property. The obtained concrete has high strength characteristics, delayed strength gain rate due to replacement of part of the binder with ash. Introduction of the fly ash increases degree of

  13. 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.

  14. 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....

  15. Numerical simulation of mechanical compaction of deepwater shallow sediments

    Science.gov (United States)

    Sun, Jin; Wu, Shiguo; Deng, Jingen; Lin, Hai; Zhang, Hanyu; Wang, Jiliang; Gao, Jinwei

    2018-02-01

    To study the compaction law and overpressure evolution in deepwater shallow sediments, a large-strain compaction model that considers material nonlinearity and moving boundary is formulated. The model considers the dependence of permeability and material properties on void ratio. The modified Cam-Clay model is selected as the constitutive relations of the sediments, and the deactivation/reactivation method is used to capture the moving top surface during the deposition process. A one-dimensional model is used to study the compaction law of the shallow sediments. Results show that the settlement of the shallow sediments is large under their own weight during compaction. The void ratio decreases strictly with burial depth and decreases more quickly near the seafloor than in the deeper layers. The generation of abnormal pressure in the shallow flow sands is closely related to the compaction law of shallow sediments. The two main factors that affect the generation of overpressure in the sands are deposition rate and permeability of overlying clay sediments. Overpressure increases with an increase in deposition rate and a decrease in the permeability of the overlying clay sediment. Moreover, an upper limit for the overpressure exists. A two-dimensional model is used to study the differential compaction of the shallow sediments. The pore pressure will still increase due to the inflow of the pore fluid from the neighboring clay sediment even though the deposition process is interrupted.

  16. Research on in-pile release of fission products from coated particle fuels

    International Nuclear Information System (INIS)

    Fukuda, K.; Iwamoto, K.

    1985-01-01

    Coated particle fuels fabricated in accordance with VHTR (Very High Temperature gas-cooled Reactor) fuel design have been irradiated by both capsules and an in-pile gas loop (OGL-1), and data on the fission products release under irradiation were obtained for loose coated particles, fuel compacts and fuel rods in the temperature range between 800 deg. C and 1600 deg. C. For the fission gases, temperature- and time dependences of the fractional release(R/B) were measured. Relation between release and failure fraction of the coated particles was elucidated on the VHTR reference fuels. Also measured was tritium concentration in the helium coolant of OGL-1. In-pile release behavior of the metallic fission products was studied by measuring the activities of the fission products adsorbed in the graphite sleeves of the OGL-1 fuel rods and the graphite fuel container of the sweep gas capsules in the PIE. Investigation on palladium interaction with SiC coating layer was included. (author)

  17. 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.)

  18. Study of Various Techniques for Improving Weak and Compressible Clay Soil under a High Earth Embankment

    Directory of Open Access Journals (Sweden)

    Zein A.K. M.

    2014-04-01

    Full Text Available This paper investigates the suitability of three soil improvement techniques for the construction of a high earth embankment on thick weak and highly compressible clay soil. The eastern approach embankment of Alhalfaya Bridge on the River Nile linking Khartoum North and Omdurman cities was chosen as a case study and a comprehensive site investigation program was carried out to determine the properties the subsurface soils. The study results showed that unless the subsurface soils have been improved they may fail or undergo excessively large settlements due to the embankment construction. Three ground improvement techniques based on the principles of the “staged construction method, SCM”, “vertical sand drain, VSD” and “sand compaction piles, SCP” of embankment foundation soil treatment are discussed and evaluated. Embankment design options based on applications of the above methods have been proposed for foundation treatment to adequately support embankment loads. A method performance evaluation based on the improvement of soil properties achieved; the time required for construction and compared estimated costs criteria was made to assess the effectiveness and expected overall performance. Adoption of any of the soil improvement techniques considered depends mainly on the most critical and decisive factor governing the embankment design. Based on the overall performance for the embankment case studied, the sand drains is considered as the most appropriate improvement method followed by the sand compaction piles technique whereas the staged construction method showed the poorest overall performance.

  19. 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...

  20. 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.

  1. 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.)

  2. 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.

  3. 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 ...

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. SHEAR STRENGTH, COLLAPSIBILITY AND COMPRESSIBILITY CHARACTERISTICS OF COMPACTED BAIJI DUNE SOILS

    Directory of Open Access Journals (Sweden)

    ABBAS JAWAD AL-TAIE

    2017-03-01

    Full Text Available Baiji city is a vital industrial centre in Iraq since it has the biggest oil refinery. Therefore, Baiji has become an attractive site for strategic construction projects. Dune sand covers about 220 km2 of the area of Baiji city. However, few researches had attempted to study its behaviour. In this study laboratory tests were conducted to determine the shear strength, collapsibility and compressibility of the dune sand at its natural and compacted status. The effect of dry unit weight, moisture content, relative density and soaking on mechanical properties of dune soil was investigated. The results demonstrated that dry and soaked dune specimens tested at their in-situ condition exhibited similar volume changes during shear and identical friction angles. The results of shear tests of both of compacted soaked and unsoaked samples were identical. The collapse potential of dune soil is inversely proportional with the relative density. The minimum axial strain is observed when the samples are compacted to modified effort. The compression index of the compacted specimens is affected by moulding water content, while the rebound index is less sensitive.

  11. Improving the geotechnical behavior of sand through cohesive admixtures

    Directory of Open Access Journals (Sweden)

    Mohie eldin Mohamed Afify Elmashad

    2018-04-01

    Full Text Available Irrigation projects in Egypt have been facing tremendous challenges, mostly is the scarcity of irrigation water. The current research presents the effect of different cohesive admixture on the conductivity of siliceous sand in general and its other geotechnical properties. Two different types of conventional swelling clay from (Toshka, 6th of October as well as bentonite were used to construct the irrigation canals and embankment. The results indicated that increase in the plasticity properties of the treated soil also decrease the permeability and infiltration. Moreover, the dry density of 2.08 t/m3 was obtained from sand and 20% 6th of October mixture, also the CBR of 31.20% were obtained from sand and 8% 6th of October mixture. Increasing the bentonite ratio increases the cohesion and decreasing the permeability. The swelling ratios of sand 6th of October Clay mixture is equal to 0.28%, and the fictitious stress at which the swelling ratio is nil, is equal to 16 kPa. Keywords: Sand, Swelling clay, Bentonite, Compaction test, Consolidation test, Triaxial test

  12. 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...

  13. ANN modelling for the determination of moulding sand matrix grain size

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2011-10-01

    Full Text Available One of the modern methods of the production optimisation are artificial neural networks. Neural networks are gaining broader and broader application in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castings and supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressure castings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. The presented investigations were obtained by using the Statistica 9.0 program. The aim of the investigations was to select the neural network suitable for prediction the moulding sand matrix grain size on the basis of the determined sand properties such as: permeability, compactibility, and compressive strength.

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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...

  19. 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.

  20. 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

  1. 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.

  2. 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...

  3. Physical and numerical modelling of earth pressure on anchored sheet pile walls in sand

    DEFF Research Database (Denmark)

    Krogsbøll, Anette Susanne; Fuglsang, Leif D

    2006-01-01

    The influence of wall flexibility on earth pressure, bending moments and failure modes is studied. Numerical models are compared to results from model tests carried out in a geotechnical centrifuge. The back-fill is dry sand and failure is introduced by allowing the wall to rotate around the anchor...

  4. Geotechnical properties of oil-contaminated Kuwaiti sand

    Energy Technology Data Exchange (ETDEWEB)

    Al-Sanad, H.A.; Eid, W.K.; Ismael, N.F. [Kuwait Univ., Safat (Kuwait). Dept. of Civil Engineering

    1995-05-01

    Large quantities of oil-contaminated sands resulted from exploded oil wells, burning oil fires, the destruction of oil storage tanks, and the formation of oil lakes in Kuwait at the end of the Gulf War. An extensive laboratory testing program was carried out to determine the geotechnical characteristics of this material. Testing included basic properties, compaction and permeability tests, and triaxial and consolidation tests on clean and contaminated sand at the same relative density. Contaminated specimens were prepared by mixing the sand with oil in the amount of 6% by weight or less to match field conditions. The influence of the type of oil, and relative density was also investigated by direct shear tests. The results indicated a small reduction in strength and permeability and an increase in compressibility due to contamination. The preferred method of disposal of this material is to use it as a stabilizing material for other projects such as road construction.

  5. Geotechnical properties of oil-contaminated Kuwaiti sand

    International Nuclear Information System (INIS)

    Al-Sanad, H.A.; Eid, W.K.; Ismael, N.F.

    1995-01-01

    Large quantities of oil-contaminated sands resulted from exploded oil wells, burning oil fires, the destruction of oil storage tanks, and the formation of oil lakes in Kuwait at the end of the Gulf War. An extensive laboratory testing program was carried out to determine the geotechnical characteristics of this material. Testing included basic properties, compaction and permeability tests, and triaxial and consolidation tests on clean and contaminated sand at the same relative density. Contaminated specimens were prepared by mixing the sand with oil in the amount of 6% by weight or less to match field conditions. The influence of the type of oil, and relative density was also investigated by direct shear tests. The results indicated a small reduction in strength and permeability and an increase in compressibility due to contamination. The preferred method of disposal of this material is to use it as a stabilizing material for other projects such as road construction

  6. 复杂地层条件下的人工挖孔桩%HAND-DUG PILES IN THE COMPLEX LAYER

    Institute of Scientific and Technical Information of China (English)

    李奋强

    2001-01-01

    介绍了几种复杂条件下人工挖孔桩的施工工艺和措施,提供了一个标准厂房基础流砂层处理的实例。%The paper presented the construction and treatment of the hand-dug piles in several kind of complex layer,also gave a case how to treat a quick sand layer under the foundation of normal workshop building.

  7. Dissolution and time-dependent compaction of albite sand: experiments at 100°C and 160°C in pH-buffered organic acids and distilled water

    Science.gov (United States)

    Hajash, Andrew; Carpenter, Thomas D.; Dewers, Thomas A.

    1998-09-01

    Aqueous fluids are important in the diagenesis and deformation of crustal rocks. Both chemical and physical interactions are involved and often they are strongly coupled. For example, pore waters not only dissolve, transport, and precipitate chemical species, but they also substantially affect the mechanical behavior of the rocks that contain them. Stresses magnified at grain contacts by differences in pore-fluid pressure ( Pp) and confining pressure ( Pc) can, in turn, influence the rate and extent of chemical exchange. To begin investigation of these coupled systems, compaction experiments were conducted using albite sand (250-500 μm) and distilled water (pH 5.8), 0.07 M acetate (pH 4.7), and 0.07 M acetate + 0.005 M citrate (pH 4.4) solutions in a hydrothermal flow-through system at conditions that simulate diagenesis. Pore-fluid chemistry and pore-volume loss were monitored to quantify the effects of organic acids on time-dependent compaction rates. The effects of stress and fluid chemistry on the dissolution kinetics were also examined. Albite dissolution rates, monitored by steady-state fluid chemistry, increased when an effective pressure ( Pe= Pc- Pp) was applied, probably due to increases in total surface area caused by grain breakage at contacts. These effects were transient in distilled water, however, Si and Al concentrations remained elevated in the acetate pore fluid. The average Si-based release rates indicate ≈35% increase in reactive surface area by application of Pe=34.5 MPa. At 100°C with Pe=34.5 MPa, steady-state Si concentrations were ≈2.3 times higher in 0.07 M acetate and 5.8 times higher in 0.07 M acetate + 0.005 M citrate than in distilled water. Al increased by even larger factors (3× in the acetate buffer and 10× in the citrate solution). These changes in fluid chemistry are attributed to both pH and ligand-enhanced reactions. Albite dissolution appears to be controlled by surface complexation reactions at Al sites. Rapid

  8. 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...

  9. Valorisation du sable de concassage et du sable du désert dans la composition des bétons autoplaçants Valorization of the crushed sand and of the desert sand in the composition of the self compacting concrete

    Directory of Open Access Journals (Sweden)

    R’mili A.

    2012-09-01

    Full Text Available Les bétons autopla÷ants (BAP sont des bétons très fluides qui demandent des dosages élevés en sables et en éléments fins par rapport au béton ordinaire (BO. Le sable de concassage (SC, à granularité étalée, est un sous-produit de concassage des roches massives. Le sable du désert (SD est un sable extra-fin, caractérisé par une distribution serrée de grosseur des grains. Renfermant des teneurs importantes en fines, ces deux sables peuvent êtres des composants intéressants des BAP. Cette recherché consiste à incorporer le SC dans la composition des bétons et étudier l’effet de son remplacement progressif par le SD sur le comportement à l’état frais et durci des BAP. L’étude expérimentale montre que les paramètres d’ouvrabilité des BAP sont améliorés lorsque le SC est partiellement remplacé par le SD ( 30%, des quantités supplémentaires en eau et en superplastifiant sont nécessaires, pour répondre aux propriétés autopla÷antes. Les résistances mécaniques diminuent en ajoutant le SD au SC, mais elles atteignent des valeurs acceptables pour des dosages modérés en SD. Les performances des BAP sont nettement meilleures que celles des BO confectionnées avec les mêmes granulats. Les essais de spécification de la durabilité montrent que les coefficients d’absorption d’eau par capillarité et par immersion augmentent en ajoutant le SD au SC alors que le coefficient de perméabilité diminue. Self-compacting concretes (SCC are highly fluid concretes that require high proportions in sand and fine particles with respect to the ordinary concrete (OC. The crushed sand (CS, spread granulometry, is a by-product of crushing rock mass. The desert sand (DS is an extra fine sand, characterized by a tight distribution of grain size. Containing significant levels of fine sand, these two sands can be both interesting components of the SCC. This research is to incorporate the CS in the composition of concrete and

  10. 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

  11. 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.

  12. 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)

  13. 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

  14. 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.

  15. 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.

  16. 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...

  17. 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

  18. 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.

  19. 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

  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. 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.

  5. 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.)

  6. 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.

  7. 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.

  8. Empirical approach based on centrifuge testing for cyclic deformations of laterally loaded piles in sand

    DEFF Research Database (Denmark)

    Truong, P.; Lehane, B. M.; Zania, Varvara

    2018-01-01

    A systematic study into the response of monopiles to lateral cyclic loading in medium dense and dense sand was performed in beam and drum centrifuge tests. The centrifuge tests were carried out at different cyclic load and magnitude ratios, while the cyclic load sequence was also varied...

  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. 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

  14. 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

  15. 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...

  16. 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

  17. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    Science.gov (United States)

    Palaniappan, Jayanthi

    2017-04-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  18. 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

  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. Investigation of the selected properties of dusts from the reclamation of spent sands with bentonite

    Directory of Open Access Journals (Sweden)

    J. Kamińska

    2011-10-01

    Full Text Available The investigation results of the selected properties of dusts generated during the mechanical reclamation of spent sands with bentonite as well as dusts from the dedusting system of sand processing plant are presented in the hereby paper. Investigations were performed with regard to determination conditions allowing to pelletise dusts in the bowl granulator. The verified methods of testing physical and chemical dust properties such as: specific density, bulk density of loosely put materials and apparent density of compacted materials together with their corresponding porosity, ignition losses and pH values, were applied. Granular composition of dusts generated during abrasion of spent binding materials in mechanical dry reclamation processes of spent sands with bentonite and coal dusts were performed by the laser diffraction analysis, allowing to broaden the measuring range of particle diameters. The optimal wetting agent content (in this case water at which the dust-water mixture obtains the best strength properties – after compacting by means of the standard moulder’s rammer – was determined.

  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. The Effect of the Kind of Sands and Additions on the Mechanical Behaviour of S.C.C

    Science.gov (United States)

    Zeghichi, L.; Benghazi, Z.; Baali, L.

    The sand is an inert element essential in the composition of concrete; its use ensures granular continuity between the cement and gravel for better cohesion of concrete. This paper presents the results of a study that investigated the influence of sand quality on the properties of fresh and hardened self-compacting concrete (SCC). The dune sands are very fine materials characterized by a high intergranular porosity, high surface area and low fineness modulus; on the other hand crushed (manufactured) sand has a high rate into thin and irregular shapes which are influencing the workability of concrete. The amount of dune sand varies from (0% 50%, to 100%) by weight of fine aggregates. The effect of additions is also treated (blast furnace slag and lime stone) The results show that the rheological properties favour the use of dune sands; however the mechanical properties support the use of crushed sand.

  8. 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...

  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. Assessment of soil compaction properties based on surface wave techniques

    Science.gov (United States)

    Jihan Syamimi Jafri, Nur; Rahim, Mohd Asri Ab; Zahid, Mohd Zulham Affandi Mohd; Faizah Bawadi, Nor; Munsif Ahmad, Muhammad; Faizal Mansor, Ahmad; Omar, Wan Mohd Sabki Wan

    2018-03-01

    Soil compaction plays an important role in every construction activities to reduce risks of any damage. Traditionally, methods of assessing compaction include field tests and invasive penetration tests for compacted areas have great limitations, which caused time-consuming in evaluating large areas. Thus, this study proposed the possibility of using non-invasive surface wave method like Multi-channel Analysis of Surface Wave (MASW) as a useful tool for assessing soil compaction. The aim of this study was to determine the shear wave velocity profiles and field density of compacted soils under varying compaction efforts by using MASW method. Pre and post compaction of MASW survey were conducted at Pauh Campus, UniMAP after applying rolling compaction with variation of passes (2, 6 and 10). Each seismic data was recorded by GEODE seismograph. Sand replacement test was conducted for each survey line to obtain the field density data. All seismic data were processed using SeisImager/SW software. The results show the shear wave velocity profiles increase with the number of passes from 0 to 6 passes, but decrease after 10 passes. This method could attract the interest of geotechnical community, as it can be an alternative tool to the standard test for assessing of soil compaction in the field operation.

  11. 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

  12. 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.

  13. Determination of p-y Curves for Bucket Foundations in Silt and Sand Using Finite Element Modelling

    DEFF Research Database (Denmark)

    Vethanayagam, Vinojan; Ibsen, Lars Bo

    slender than the tested piles. The suction bucket has a slenderness ratio of 0.5-1, thus its response is a rigid movement, where slender piles undergoes a flexible movement. Due to the importance of precise estimations, p-y formulations for suction buckets in drained and undrained silt are sought...... developed with use of finite element. In general the developed p-y formulations for the drained and undrained silt are fairly precise. Furthermore, the same method and basic formulation of the drained silt is applied to data of the drained sand from Østergaard et al. [2015]. The developed formulation...... herefore shows to be more versatile and precise than the formulation suggested by Østergaard et al. [2015]. The developed p-y formulations are functions of the effective vertical in-situ stress, soil stiffness, diameter of the bucket and the internal friction angle/the undrained shear strength....

  14. Filtration behavior of organic substance through a compacted bentonite

    International Nuclear Information System (INIS)

    Kanaji, Mariko; Kuno, Yoshio; Yui, Mikazu

    1999-07-01

    Filtration behavior of organic substance through a compacted bentonite was investigated. Na-type bentonite containing 30wt% of quartz sand was compacted in a column and the dry density was adjusted to be 1.6 g/cm 3 . Polyacrylic acid solution (including three types of polyacrylic acid, average molecular weight 2,100, 15,000 and 450,000) was prepared and was passed through the compacted bentonite. Molecular weight distributions of polyacrylic acid in the effluent solution were analysed by GPC (Gel Permeation Chromatography). A batch type experiment was also carried out in order to examine a sorption behavior of these organic substances onto the surfaces of grains of the bentonite. The results indicated that the smaller size polyacrylic acid (molecular weight < 100,000) was passed through the compacted bentonite. On the other hand, the larger size polyacrylic acid (molecular weight ≥100,000) was mostly filtrated by the compacted bentonite. The batch type sorption tests clarified that the polyacrylic acid did not sorb onto the surfaces of minerals constituting the bentonite. Therefore it was suggested that the larger size molecules (≥100,000) of organic substances could be predominantly filtrated by the microstructure of the compacted bentonite. (author)

  15. 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...

  16. 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.

  17. 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...

  18. Placement of pre-compacted and in situ compacted dense backfill materials in shaft seals

    International Nuclear Information System (INIS)

    Martino, J.; Dixon, D.; Kim, C.S.

    2010-01-01

    Document available in extended abstract form only. In 2003, a decision was made to discontinue operation of Atomic Energy of Canada Limited's (AECL's) Underground Research Laboratory (URL) and ultimately to decommission and permanently close the underground portion of this facility. As part of the Nuclear Legacy Liability Program (NLLP) being funded by Natural Resources Canada (NRCan), an ongoing program of work is being undertaken to decommission and deal with facilities that are no longer part of AECL's mandate or operations. The URL is included in these facilities. Part of this work is the installation of seals at the intersection of the access and ventilation shafts and an ancient thrust fault, Fracture Zone 2 (FZ2), approximately 275 m below surface. These seals are being installed in order to limit the potential for mixing of deeper saline and shallower, less saline groundwater. The seal design in each shaft is similar with a heavily reinforced lower concrete component, a central bentonite clay-sand component and an upper un-reinforced concrete component. The main shaft at the URL at the location of the seal is circular (∼5-m diameter), and was excavated using careful drill and blast techniques. The seal itself consists of two keyed, conical sectioned, 3-m-thick by 5 to 6-m diameter concrete segments that confine a 6-m-thick swelling clay section. The ventilation shaft at the URL is 1.8 m in diameter and was excavated using raise-boring. The ventilation shaft will consist of two keyed, conical sectioned, 2-m-thick concrete by 1.8 to 2.8 m diameter concrete segments confining a 5-m-thick assembly of pre-compacted clay-sand blocks. The concrete is a low pH concrete designed for repository use, which can develop a 70 MPa unconfined compressive strength after 28 days. It has a pH of less than 11 achieved by substitution of 75% of the cement powder with silica fume and ground silica so the likelihood of free calcium and an alkaline plume is

  19. 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.

  20. A Study of Compressive Strength Characteristics of Laterite Sand Hollow Blocks

    Directory of Open Access Journals (Sweden)

    Abiodun Olanipekun

    2007-01-01

    Full Text Available This paper presents the results of experimental investigations carried out on partial replacement of sand with laterite as it affects the compressive strength of sandcrete hollow blocks. Two mix proportions (1:6 and 1:8 were used with laterite content varying between 0 and 50% at 10% intervals. Hand and machine compaction methods were used. Curing was done by sprinkling water on the specimens. The results showed that for each mix proportion and compaction method, the compressive strength decreases with increase in laterite content. Machine compacted hollow sandcrete blocks made from mix ratio 1:6 and with up to 10% laterite content is found suitable and hence recommended for building construction having attained a 28-day compressive strength of 2.07N/mm2 as required by the Nigerian Standards.

  1. 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

  2. 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.

  3. 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....

  4. 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

  5. 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.)

  6. Influence green sand system by core sand additions

    Directory of Open Access Journals (Sweden)

    N. Špirutová

    2012-01-01

    Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

  7. 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

  8. 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.

  9. 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

  10. Booming Sand Dunes

    Science.gov (United States)

    Vriend, Nathalie

    "Booming" sand dunes are able to produce low-frequency sound that resembles a pure note from a music instrument. The sound has a dominant audible frequency (70-105 Hz) and several higher harmonics and may be heard from far distances away. A natural or induced avalanche from a slip face of the booming dune triggers the emission that may last for several minutes. There are various references in travel literature to the phenomenon, but to date no scientific explanation covered all field observations. This thesis introduces a new physical model that describes the phenomenon of booming dunes. The waveguide model explains the selection of the booming frequency and the amplification of the sound in terms of constructive interference in a confined geometry. The frequency of the booming is a direct function of the dimensions and velocities in the waveguide. The higher harmonics are related to the higher modes of propagation in the waveguide. The experimental validation includes quantitative field research at the booming dunes of the Mojave Desert and Death Valley National Park. Microphone and geophone recordings of the acoustic and seismic emission show a variation of booming frequency in space and time. The analysis of the sensor data quantifies wave propagation characteristics such as speed, dispersion, and nonlinear effects and allows the distinction between the source mechanism of the booming and the booming itself. The migration of sand dunes results from a complicated interplay between dune building, wind regime, and precipitation. The morphological and morphodynamical characteristics of two field locations are analyzed with various geophysical techniques. Ground-penetrating radar images the subsurface structure of the dunes and reveal a natural, internal layering that is directly related to the history of dune migration. The seismic velocity increases abruptly with depth and gradually increases with downhill position due to compaction. Sand sampling shows local

  11. 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....

  12. Selected parameters of moulding sands for designing quality control systems

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2010-07-01

    Full Text Available One of the modern methods of production optimisation are artificial neural networks. Neural networks owe their popularity to the fact thatthey are convenient tools, which can be utilised in a wide scope of problems. They are capable of reflecting complex functions. Especiallytheir non-linearity should be emphasised. They are gaining wider and wider application in the foundry industry, among others, to controlmelting processes in cupolas and arc furnaces, designing castings and supply systems, control of moulding sands treatments, prediction ofproperties of cast alloys as well as selecting die casting.An attempt of the application neural networks to the quality control of moulding sands with bentonite is presented in the paper. This isa method of assessing the suitability of moulding sands by finding correlations in between individual parameters, by means of artificialneural network systems. The presented investigations were performed with the application of the Statistica 8.0 program.The investigations were aimed at the selection of the proper kind of a neural network for prediction a sand moistness on the bases ofcertain moulding sand properties such as: permeability, compactibility and friability. These parameters – determined as sand moistness functions - were introduced as initial parameters.Application of the Statistica program allowed for an automatic selection of the most suitable network for the reflection of dependencies and interactions existing among the proposed parameters. The best results were obtained for unidirectional multi-layer perception network (MLP. The neural network sensitivity to individual moulding sand parameters was determined, which allowed to reject not important parameters when constructing the network.

  13. 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...

  14. 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...

  15. 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

  16. 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

  17. 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)

  18. Principles of control automation of soil compacting machine operating mechanism

    Science.gov (United States)

    Anatoly Fedorovich, Tikhonov; Drozdov, Anatoly

    2018-03-01

    The relevance of the qualitative compaction of soil bases in the erection of embankment and foundations in building and structure construction is given.The quality of the compactible gravel and sandy soils provides the bearing capability and, accordingly, the strength and durability of constructed buildings.It has been established that the compaction quality depends on many external actions, such as surface roughness and soil moisture; granulometry, chemical composition and degree of elasticity of originalfilled soil for compaction.The analysis of technological processes of soil bases compaction of foreign and domestic information sources showed that the solution of such important problem as a continuous monitoring of soil compaction actual degree in the process of machine operation carry out only with the use of modern means of automation. An effective vibrodynamic method of gravel and sand material sealing for the building structure foundations for various applications was justified and suggested.The method of continuous monitoring the soil compaction by measurement of the amplitudes and frequencies of harmonic oscillations on the compactible surface was determined, which allowed to determine the basic elements of facilities of soil compacting machine monitoring system of operating, etc. mechanisms: an accelerometer, a bandpass filter, a vibro-harmonics, an on-board microcontroller. Adjustable parameters have been established to improve the soil compaction degree and the soil compacting machine performance, and the adjustable parameter dependences on the overall indexhave been experimentally determined, which is the soil compaction degree.A structural scheme of automatic control of the soil compacting machine control mechanism and theoperation algorithm has been developed.

  19. The influence of organic matter content and media compaction on the dispersal of entomopathogenic nematodes with different foraging strategies.

    Science.gov (United States)

    Kapranas, Apostolos; Maher, Abigail M D; Griffin, Christine T

    2017-12-01

    In laboratory experiments, we investigated how media with varying ratio of peat:sand and two levels of compaction influence dispersal success of entomopathogenic nematode (EPN) species with different foraging strategies: Steinernema carpocapsae (ambusher), Heterorhabditis downesi (cruiser) and Steinernema feltiae (intermediate). Success was measured by the numbers of nematodes moving through a 4 cm column and invading a wax moth larva. We found that both compaction and increasing peat content generally decreased EPN infective juvenile (IJ) success for all three species. Of the three species, H. downesi was the least affected by peat content, and S. carpocapsae was the most adversely influenced by compaction. In addition, sex ratios of the invading IJs of the two Steinernema species were differentially influenced by peat content, and in the case of S. feltiae, sex ratio was also affected by compaction. This indicates that dispersal of male and female IJs is differentially affected by soil parameters and that this differentiation is species-specific. In conclusion, our study shows that organic matter: sand ratio and soil compaction have a marked influence on EPN foraging behaviour with implications for harnessing them as biological pest control agents.

  20. 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

  1. 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...

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. 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...

  9. Ceramographic Examinations of Irradiated AGR-1 Fuel Compacts

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz; Scott Ploger; John Hunn

    2012-05-01

    The AGR 1 experiment involved irradiating 72 cylindrical fuel compacts containing tri-structural isotropic (TRISO)-coated particles to a peak burnup of 19.5% fissions per initial metal atom with no in-pile failures observed out of almost 300,000 particles. Five irradiated AGR 1 fuel compacts were selected for microscopy that span a range of irradiation conditions (temperature, burnup, and fast fluence). These five compacts also included all four TRISO coating variations irradiated in the AGR experiment. The five compacts were cross-sectioned both transversely and longitudinally, mounted, ground, and polished after development of careful techniques for preserving particle structures against preparation damage. Approximately 40 to 80 particles within each cross section were exposed near enough to mid-plane for optical microscopy of kernel, buffer, and coating behavior. The microstructural analysis focused on kernel swelling and porosity, buffer densification and fracture, debonding between the buffer and inner pyrolytic carbon (IPyC) layers, and fractures in the IPyC and SiC layers. Three basic particle morphologies were established according to the extent of bonding between the buffer and IPyC layers: complete debonding along the interface (Type A), no debonding along the interface (Type B), and partial debonding (Type AB). These basic morphologies were subdivided according to whether the buffer stayed intact or fractured. The resulting six characteristic morphologies were used to classify particles within each cross section, but no spatial patterns were clearly observed in any of the cross-sectional morphology maps. Although positions of particle types appeared random within compacts, examining a total of 830 classified particles allowed other relationships among morphological types to be established.

  10. Ceramographic Examinations of Irradiated AGR-1 Fuel Compacts

    International Nuclear Information System (INIS)

    Demkowicz, Paul; Ploger, Scott; Hunn, John

    2012-01-01

    The AGR 1 experiment involved irradiating 72 cylindrical fuel compacts containing tri-structural isotropic (TRISO)-coated particles to a peak burnup of 19.5% fissions per initial metal atom with no in-pile failures observed out of almost 300,000 particles. Five irradiated AGR 1 fuel compacts were selected for microscopy that span a range of irradiation conditions (temperature, burnup, and fast fluence). These five compacts also included all four TRISO coating variations irradiated in the AGR experiment. The five compacts were cross-sectioned both transversely and longitudinally, mounted, ground, and polished after development of careful techniques for preserving particle structures against preparation damage. Approximately 40 to 80 particles within each cross section were exposed near enough to mid-plane for optical microscopy of kernel, buffer, and coating behavior. The microstructural analysis focused on kernel swelling and porosity, buffer densification and fracture, debonding between the buffer and inner pyrolytic carbon (IPyC) layers, and fractures in the IPyC and SiC layers. Three basic particle morphologies were established according to the extent of bonding between the buffer and IPyC layers: complete debonding along the interface (Type A), no debonding along the interface (Type B), and partial debonding (Type AB). These basic morphologies were subdivided according to whether the buffer stayed intact or fractured. The resulting six characteristic morphologies were used to classify particles within each cross section, but no spatial patterns were clearly observed in any of the cross-sectional morphology maps. Although positions of particle types appeared random within compacts, examining a total of 830 classified particles allowed other relationships among morphological types to be established.

  11. 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....

  12. How to Make Eccentricity Cycles in Stratigraphy: the Role of Compaction

    Science.gov (United States)

    Liu, W.; Hinnov, L.; Wu, H.; Pas, D.

    2017-12-01

    Milankovitch cycles from astronomically driven climate variations have been demonstrated as preserved in cyclostratigraphy throughout geologic time. These stratigraphic cycles have been identified in many types of proxies, e.g., gamma ray, magnetic susceptibility, oxygen isotopes, carbonate content, grayscale, etc. However, the commonly prominent spectral power of orbital eccentricity cycles in stratigraphy is paradoxical to insolation, which is dominated by precession index power. How is the spectral power transferred from precession to eccentricity in stratigraphy? Nonlinear sedimentation and bioturbation have long been identified as players in this transference. Here, we propose that in the absence of bioturbation differential compaction can generate the transference. Using insolation time series, we trace the steps by which insolation is transformed into stratigraphy, and how differential compaction of lithology acts to transfer spectral power from precession to eccentricity. Differential compaction is applied to unique values of insolation, which is assumed to control the type of deposited sediment. High compaction is applied to muds, and progressively lower compaction is applied to silts and sands, or carbonate. Linear differential compaction promotes eccentricity spectral power, but nonlinear differential compaction elevates eccentricity spectral power to dominance and precession spectral power to near collapse as is often observed in real stratigraphy. Keywords: differential compaction, cyclostratigraphy, insolation, eccentricity

  13. 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)

  14. 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. ...

  15. Petrographic, mineralogical and geochemical characterization of the Serrinha coal waste pile (Douro Coalfield, Portugal) and the potential environmental impacts on soil, sediments and surface waters

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, J. [Centro de Geologia, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Ferreira da Silva, E. [GeoBioTec, Geobiosciences, Geotechnologies and Geoengineering Research Center, Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal); Li, Z.; Ward, C. [School of Biological, Earth and Environmental Sciences, University of New South Wales. Sydney, NSW 2052 (Australia); Flores, D. [Departamento de Geociencias, Ambiente e Ordenamento do Territorio, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal)

    2010-09-01

    Serrinha is the largest coal waste pile resulting from mining activities in the Douro Coalfield, Portugal. The exploitation of anthracite in tens of small mines caused some environmental impacts, as is the case of the coal waste piles that exist in old mines and adjacent areas. The Serrinha waste pile is essentially made up of 2 million tonnes of shales and carbonaceous shales, deposited in a topographical depression over about 30 years. Despite the environmental restoration accomplished in the Serrinha waste pile, some environmental problems seem to persist. In this study a petrographic, mineralogical and geochemical characterization was done in order to recognize and understand these problems. The materials studied were coal waste, sediments and waters from the drainage system and decanting basins, soils from the surrounding areas, leachates from waste material and neoformed minerals formed at the bottom of the waste pile. The main lithologies (carbonaceous shale and lithic arenite) and coal from the Douro Coalfield were also analyzed. Petrographic analysis shows some evidence of weathering (on organic and inorganic matter) related to the time of exposure to the weathering agents and the easy access of air within the waste pile (due to both the poor compaction and the heterogeneity of the material). Mineralogically, the composition of coal waste material has contributions from both the coal and the associated lithologies. R-type cluster analysis of the waste pile material allows two distinct clusters to be identified. In the first cluster a sulfide fraction is represented by the association of As, Cd, Cu, Pb, Ni and Zn, while Fe clustered with Al, Co, and Ti indicates that some of the Fe and the other elements are likely associated with silicate minerals such as clays. The second cluster, represented by Cr, V, Zr, Rb, REE, Mn, Li and Ba, probably represent a silicate fraction, perhaps detrital accessory minerals. The waste pile material, leachates, soils

  16. 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)

  17. 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...

  18. Investigation of the existence of self compacting properties in high performance concrete through experimental tests

    Directory of Open Access Journals (Sweden)

    Heitor H. Yoshida

    2007-03-01

    Full Text Available The self compacting concrete is characterized by its capacity to flow inside the formwork filling it exclusively by the force of the gravity with adequate cohesion and viscosity in such a way that segregation does not occur. One of its characteristic is the presence of fines which provide the necessary cohesion,and grains with maximum diameter of 20 mm. This work presents some procedures and experimental methods that make it possible to evaluate self compacting properties of high performance concrete. First, a bibliographical review on the subject was carried out, and later, the equipment used for the accomplishment of the assays were manufactured, in order to verify the properties related to the self compacting concrete: cohesion, viscosity and segregation. As for the work, two concretes were produced with Portland ARI Cement, thick sand, stone powder, sand 0, superplasticizer made of ether-carboxilate chains that differentiate from each other for the presence of active silica in one of them and fly ash in the other. Based on the results, it was verified whether the high performance concrete had self compacting characteristics. In this case, both were considered positive. It was also analyzed the behavior of these concretes in their hardened state by means of the compressive strength test. The Self Compacting Concrete has many advantages such as: reduction in the number of employees, shorter construction period, the non-use of the vibrator and the filling of formworks with high density of… or of complex geometry.

  19. Electrochemical reduction of water. Development of a flat cell pile

    International Nuclear Information System (INIS)

    Viguie, J.C.

    1978-01-01

    The working conditions of an electrolyser are described. Great variations of water vapor concentrations through the battery makes us advocate for piling up flat cells working under a constant potential. A 50 cm 2 half cathodic cell has been fabricated. The solid electrolyte is made of zirconia (0,91 ZrO 2 , 0,09 Y 2 O 3 ) associated with an embedded layer of nickel powder as the cathode. The disc is supported by an honeycomb shaped ceramic which is covered by a layer of nickel. The most promising method for solid electrolyte fabrication is the powder compaction and sintering process. The plasma jet projection gave interesting results and can be considered as an alternative process. A test set working at 850 0 C is on the way. It will give informations on the stability of the prepared parts and allow us to measure the characteristics of the planar cell [fr

  20. Effect of material parameters on the compactibility of backfill materials

    International Nuclear Information System (INIS)

    Keto, P.; Kuula-Vaeisaenen, P.; Ruuskanen, J.

    2006-05-01

    The effect of different parameters on compactibility of mixture of bentonite and ballast as well as Friedland-clay was studied in laboratory with two different types of compaction tests. The material parameters varied were grain size distribution of the ballast material, grain shape, water ratio and bentonite content (15/30%). The other parameters varied were salinity of the mixing water, mixing process and compaction method and energy. Ballast materials with varying grain size distributions were produced from Olkiluoto mica-gneiss with different type of crushing processes. In addition, sand was chosen for ballast material due to its uniform grain size distribution and rounded grain shape. The maximum grain size of the ballast materials was between 5-10 mm. When comparing the compactibility of ballast materials, the highest dry densities were gained for ballast materials with graded grain size distribution. The compaction behaviour of the tested bentonite ballast mixtures is dominated by the bentonite content. The other parameters varied did not have significant effect on the compactibility of the mixtures with bentonite content of 30%. This can be explained with the amount of bentonite that is higher than what is needed to fill up the volume between the ballast grains. The results gained with the two different compaction tests are comparable. Both the bentonite/ballast mixtures and the Friedland clay behaved similarly when compacted with three different compaction pressures (180, 540 and 980 kPa). (orig.)

  1. 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

  2. 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)

  3. 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.

  4. 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.

  5. Phase II, Title I engineering assessment of radioactive sands and residues, Lowman Site, Lowman Idaho

    Energy Technology Data Exchange (ETDEWEB)

    1977-12-01

    An engineering assessment was performed of the problems resulting from the existence of radioactive uranium sand residues at the Lowman, Idaho, site. Services normally include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas release from the 90,000 tons of sand residues at the Lowman site constitutes the most significant environmental impact, although external gamma radiation is also a factor. The two alternative actions presented are dike construction, fencing, and maintenance (Option I); and consolidation of the piles, addition of a 2-ft-thick stabilization cover, and on-site cleanup (Option II). Both options include remedial action at off-site structures. Cost estimates for the two options are $393,000 and $590,000.

  6. Phase II, Title I engineering assessment of radioactive sands and residues, Lowman Site, Lowman Idaho

    International Nuclear Information System (INIS)

    1977-12-01

    An engineering assessment was performed of the problems resulting from the existence of radioactive uranium sand residues at the Lowman, Idaho, site. Services normally include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas release from the 90,000 tons of sand residues at the Lowman site constitutes the most significant environmental impact, although external gamma radiation is also a factor. The two alternative actions presented are dike construction, fencing, and maintenance (Option I); and consolidation of the piles, addition of a 2-ft-thick stabilization cover, and on-site cleanup (Option II). Both options include remedial action at off-site structures. Cost estimates for the two options are $393,000 and $590,000

  7. Experimental Testing of Monopiles in Sand Subjected to One-Way Long-Term Cyclic Lateral Loading

    DEFF Research Database (Denmark)

    Roesen, Hanne Ravn; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

    2013-01-01

    In the offshore wind turbine industry the most widely used foundation type is the monopile. Due to the wave and wind forces the monopile is subjected to a strong cyclic loading with varying amplitude, maximum loading level, and varying loading period. In this paper the soil–pile interaction...... of a monopile in sand subjected to a long-term cyclic lateral loading is investigated by means of small scale tests. The tests are conducted with a mechanical loading rig capable of applying the cyclic loading as a sine signal with varying amplitude, mean loading level, and loading period for more than 60 000...... cycles. The tests are conducted in dense saturated sand. The maximum moment applied in the cyclic tests is varied from 18% to 36% of the ultimate lateral resistance found in a static loading test. The tests reveal that the accumulated rotation can be expressed by use of a power function. Further, static...

  8. 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...

  9. 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....

  10. Swelling characteristics of sand-bentonite mixtures under one-dimensional stress

    International Nuclear Information System (INIS)

    Cui, Hongbin; Sun, De'an; Matsuoka, Hajime; Xu Yongfu

    2004-01-01

    Based on the concept that the maximum water volume absorbed by unit volume of montmorillonite is constant, the swelling deformation of sand-bentonite mixtures is uniquely characterized using the void ratio of montmorillonite, which is defined by the ratio of water volume to montomorillonite volume. The relationship between the montmorillonite void ratio and overburden pressure at fully swelling is independent of the initial compaction condition and the sand-bentonite mixture ratio, and is a linear line in their log scale. When overburden pressure is large enough and/or the bentonite ratio of the mixture is small, the measured plots deviate from the line. A method for predicting the limited overburden pressure which is linearly correlated with the montmorillonite void ratio is proposed and verified using the concept of the skeleton void ratio. (author)

  11. 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.

  12. 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...

  13. 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....

  14. Augmenting Sand Simulation Environments through Subdivision and Particle Refinement

    Science.gov (United States)

    Clothier, M.; Bailey, M.

    2012-12-01

    there is a planetary rover interacting with our sand simulation environment. Sand that is actively interacting with a rover wheel will be represented as individual particles whereas sand that is further under the surface will be represented by larger regions of sand. The result of this technique allows for many particles to be represented without the computational complexity. In developing this method, we have further generalized these subdivision regions into any volumetric area suitable for use in the simulation. This is a further improvement of our method as it allows for more compact subdivision sand regions. This helps to fine tune the simulation so that more emphasis can be placed on regions of actively participating sand. We feel that through the generalization of our technique, our research can provide other opportunities within the earth and planetary sciences. Through collaboration with our academic colleagues, we continue to refine our technique and look for other opportunities to utilize our research.

  15. 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.

  16. 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

  17. 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.)

  18. Active binder content as a factor of the control system of the moulding sand quality

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2011-01-01

    Full Text Available One of the modern methods of the production optimisation are artificial neural networks. Neural networks are gaining broader and broaderapplication in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castingsand supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressurecastings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is theassessment method of sands suitability by means of detecting correlations between their individual parameters. The presentedinvestigations were obtained by using the Statistica 9.0 program. The presented investigations were aimed at the selection of the neuralnetwork able to predict the active bentonite content in the moulding sand on the basis of this sand properties such as: permeability,compactibility and the compressive strength. An application of the Statistica program allowed to select automatically the type of networkproper for the representation of dependencies occurring in between the proposed moulding sand parameters. The most advantageousconditions were obtained for the uni-directional multi-layer perception (MLP network. Knowledge of the neural network sensitivity to individual moulding sand parameters, allowed to eliminate not essential ones.

  19. 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.

  20. 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...

  1. 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...

  2. 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

  3. 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.

  4. 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)

  5. 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.

  6. Coherent change detection and interferometric ISAR measurements in the folded compact range

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, K.W.

    1996-08-01

    A folded compact range configuration has been developed ant the Sandia National Laboratories` compact range antenna and radar-cross- section measurement facility as a means of performing indoor, environmentally-controlled, far-field simulations of synthetic aperture radar (SAR) measurements of distributed target samples (i.e. gravel, sand, etc.). The folded compact range configuration has previously been used to perform coherent-change-detection (CCD) measurements, which allow disturbances to distributed targets on the order of fractions of a wavelength to be detected. This report describes follow-on CCD measurements of other distributed target samples, and also investigates the sensitivity of the CCD measurement process to changes in the relative spatial location of the SAR sensor between observations of the target. Additionally, this report describes the theoretical and practical aspects of performing interferometric inverse-synthetic-aperture-radar (IFISAR) measurements in the folded compact range environment. IFISAR measurements provide resolution of the relative heights of targets with accuracies on the order of a wavelength. Several examples are given of digital height maps that have been generated from measurements performed at the folded compact range facility.

  7. 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.)

  8. 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.

  9. 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 ...

  10. 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 ...

  11. Development of a manufacturing technology of compacted graphite iron castings from a cupola furnace

    Directory of Open Access Journals (Sweden)

    O. Bouska

    2012-01-01

    Full Text Available Compacted graphite iron, also known as vermicular cast iron or semiductile cast iron is a modern material, the production of which is increasing globaly. Recently this material has been very often used in automotive industry. This paper reviews some findigs gained during the development of the manufacturing technology of compacted graphite iron under the conditions in Slévárna Heunisch Brno, Ltd. The new technology assumes usage of cupola furnace for melting and is beeing developed for production of castings weighing up to 300 kilograms poured into bentonite sand moulds.

  12. 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.

  13. 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.

  14. Spoil pile instabilities with reference to a strip coal mine in Turkey: mechanisms and assessment of deformations

    Science.gov (United States)

    Kasmer, Ozgu; Ulusay, Resat; Gokceoglu, Candan

    2006-02-01

    With the increasing adoption of the surface mining of coal, problems associated with spoil pile instability, which affects resource recovery, mining cost, and safety and presents environmental hazards, have become a matter of prime concern to mine planners and operators. The study of geotechnical aspects is thus very important in the rational planning for the disposal, reclamation, treatment and utilization of spoil material. A strip coal mine, one of the largest open pit mines in Turkey, is located in Central Anatolia and provides coal to a thermal power station. Coal production is carried out in two adjacent open pits, the Central Pit and South Pit. A large-scale spoil pile instability over an area of 0.3 km2 occurred within the dumping area of the Central pit. In addition, small-scale movement occurred in the outside dumping area. This paper outlines the results of field and laboratory investigations to describe the mechanisms of the spoil pile instabilities and to assess deformations monitored over a long period following the failure. Shear test results indicate that the interface between the floor and spoil material dumped by dragline has a negligible cohesion and is the most critical plane of weakness for spoil pile instability. Back analyses based on the method of limit equilibrium and the numerical modelling technique, and observations in the pit revealed that failure occurred along a combined sliding surface consisting of a circular surface through the spoil material itself and a planar surface passing along the interface between the spoil piles and floor. The analyses also indicated that pore water pressure ratios of about 0.25 satisfy limiting equilibrium condition and that rainfall about one month before the failure may be a contributing factor to the instability. Movement monitoring data obtained following the failure over a 1.5-year period suggested that the ongoing deformations were mainly due to compaction of the spoil material. Based on the

  15. STRAIN-STRESS DISTRIBUTION OF “HOMOGENEOUS” SOIL MASS DURING THE LOAD TRANSMITTED THROUGH THE LIMITED AREA IN THE PLAN, APPLIED INSIDE THE ELASTIC HOMOGENEOUS SOIL MASS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2017-03-01

    Full Text Available Summary. Based on the current understanding of the piles work in clayey soils; that is forming during driving process a compacted core (compacted platform in the pile tip plane and transferring the load from the pile (from the piling foundation not through the pile tip but through the pressed core (compacted platform, the stress in the soil mass by the load applied inside the elastic half-space is determined with the change in the calculated scheme of load transferring to the “homogeneous” soil mass.

  16. 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

  17. 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.

  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. 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....

  20. 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.

  1. 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.

  2. The uniform design experimental research of a large amount of fly ash self-compaction concrete

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, M.; Ji, C.; Xiao, J. [Liaoning Technical University, Fuxin (China)

    2005-08-15

    The paper studied the effect of quantity of cementing material and fly ash, W/B (water-binder) ratio, admixture and sand percentage to the performance of super fly-ash self-compaction concrete. It also utilized the step-by-step regression analysis method in SPSS software to found regression equation, which uses the flow rate of concrete mixture and strength of concrete as objective function, and obtained the optimum mix proportion of super fly ash self-compaction by the optimization technology in the Matlab software.

  3. 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...

  4. 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)

  5. Environmental Impacts of Sand Exploitation. Analysis of Sand Market

    Directory of Open Access Journals (Sweden)

    Marius Dan Gavriletea

    2017-06-01

    Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

  6. 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

  7. 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…

  8. Comparison of bacteria populations in clean and recycled sand used for bedding in dairy facilities.

    Science.gov (United States)

    Kristula, M A; Rogers, W; Hogan, J S; Sabo, M

    2005-12-01

    Bedding samples were collected twice from commercial dairy free-stall facilities that used recycled sand and clean sand in both the summer and winter. Collection began on the day sand was taken from the pile (d 0) and placed in the free stalls, and continued for 5 to 7 additional days. The number of colonies per gram of bedding of gram-negative bacteria, coliforms, Streptococcus spp., and Klebsiella spp. were estimated for each sand sample as well as amounts of dry and organic matter. Clean sand (CS) and recycled sand (RS) had the same bacterial counts when compared at any sampling time. The mean counts of bacterial populations did vary over the course of the study in both CS and RS. There was a significant increase in bacterial counts from d 0 to d 1 for gram-negative bacteria, coliforms, and Streptococcus spp. in both winter and summer. Counts of gram-negative bacteria, coliforms, Klebsiella spp., and Streptococcus spp. did not differ from d 1 to 7 in the winter. Total counts of gram-negative bacteria did not differ from d 1 to 7 in the summer. On d 1 in the summer, coliform counts were lower than at d 5 to 7, and Klebsiella spp. counts were lower than on d 3 to 7. Streptococcus spp. counts were high on d 1 and were constant through d 7 in both winter and summer trials. The number of coliform and Klebsiella spp. in both CS and RS was below the threshold thought to cause mastitis during the sampling times. The number of Streptococcus spp. was high in both CS and RS during the sampling periods. Other management factors need to be identified to decrease the number of Streptococcus spp. in bedding. Recycled sand had a higher organic matter and lower dry matter compared with CS in winter and summer. The results for this study were obtained from multiple herd comparisons, and herd was a significant effect suggesting that different management systems influence the number and types of bacteria in both CS and RS.

  9. 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

  10. Compaction creep of quartz sand at 400-600°C: Experimental evidence for dissolution-controlled pressure solution

    NARCIS (Netherlands)

    Niemeijer, A.; Spiers, C.J.; Bos, B.

    2002-01-01

    Intergranular pressure solution (IPS) is an important compaction and deformation mechanism in quartzose rocks, but the kinetics and rate-controlling process remain unclear. The aim of the present study is to test microphysical models for compaction creep by IPS against isostatic hot pressing

  11. 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...

  12. 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

  13. 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.

  14. 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...

  15. 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...

  16. 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

  17. 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.

  18. Study on GMZ bentonite-sand mixture by undrained triaxial tests

    Directory of Open Access Journals (Sweden)

    Sun Wen-jing

    2016-01-01

    Full Text Available It is particularly necessary to study the deformation, strength and the changes of pore water pressure of bentonite-based buffer/backfill materials under the undrained condition. A series of isotropic compression tests and triaxial shear tests under undrained conditions were conducted on the compacted saturated/unsaturated GMZ bentonite-sand mixtures with dry mass ratio of bentonite/sand of 30:70. During the tests, the images of the sample were collected by photographic equipment and subsequently were cropped, binarized and centroids marked by image processing technique. Based on identification of the variation of the position of marked centroids, the deformation of the sample can be determined automatically in real-time. Finally, the hydro-mechanical behaviour of saturated and unsaturated bentonite-sand mixtures under the undrained condition can be obtained. From results of triaxial shear tests on unsaturated samples under constant water content, inflated volumetric deformation transforms to contractive volumetric deformation due to the increase of the confining pressure and lateral expansion deformation are observed due to the increase in the shearing stress. Moreover, the net mean stress affects the initial stiffness, undrained shear strength and deformation of the sample during the undrained shear tests.

  19. 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...

  20. 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...

  1. Recovery of severely compacted soils in the Mojave Desert, California, USA

    Science.gov (United States)

    Webb, R.H.

    2002-01-01

    Often as a result of large-scale military maneuvers in the past, many soils in the Mojave Desert are highly vulnerable to soil compaction, particularly when wet. Previous studies indicate that natural recovery of severely compacted desert soils is extremely slow, and some researchers have suggested that subsurface compaction may not recover. Poorly sorted soils, particularly those with a loamy sand texture, are most vulnerable to soil compaction, and these soils are the most common in alluvial fans of the Mojave Desert. Recovery of compacted soil is expected to vary as a function of precipitation amounts, wetting-and-drying cycles, freeze-thaw cycles, and bioturbation, particularly root growth. Compaction recovery, as estimated using penetration depth and bulk density, was measured at 19 sites with 32 site-time combinations, including the former World War II Army sites of Camps Ibis, Granite, Iron Mountain, Clipper, and Essex. Although compaction at these sites was caused by a wide variety of forces, ranging from human trampling to tank traffic, the data do not allow segregation of differences in recovery rates for different compaction forces. The recovery rate appears to be logarithmic, with the highest rate of change occurring in the first few decades following abandonment. Some higher-elevation sites have completely recovered from soil compaction after 70 years. Using a linear model of recovery, the full recovery time ranges from 92 to 100 years; using a logarithmic model, which asymptotically approaches full recovery, the time required for 85% recovery ranges from 105-124 years.

  2. Vibro Replacement, Dynamic Compaction, and Vibro Compaction case histories for petroleum storage tank facilities

    Energy Technology Data Exchange (ETDEWEB)

    Beaton, N; Scott, J. [Geopac West Ltd., Richmond, BC (Canada)

    2010-07-01

    This paper discussed approaches to tank farm ground improvement via 3 Canadian ground improvement case histories in order to set forth the advantages of ground improvement for foundation support at petroleum storage tank facilities. Each case study featured a particular set of site conditions, performance criteria, and ground improvement techniques selected to attain the desired foundation performance. The first case study involved a Vibro Replacement stone column to meet strict seismicity requirements, the second employed Dynamic Compaction to mitigate deep variable fill within a former gravel pit, and the last encompassed Vibro Compaction applied to a site with a sand fill soil profile. The site conditions, the design requirements, the ground improvement solution, the execution, and the quality control techniques and results were presented for each case history. Soil reinforcement and ground improvement to treat loose and soft soils below heavy storage tanks can be an economical solution to foundation design challenges. However, it is important to select proper methods and tailor the densification programs to the specific subsoil conditions and design requirements. In each application, the selected ground improvement technique exceeded the specified in-situ testing requirements. 3 refs., 9 figs.

  3. 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

  4. 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.

  5. 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

  6. 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

  7. 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...

  8. 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.

  9. 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...

  10. Investigation of in-pile grown corrosion films on zirconium-based alloys

    International Nuclear Information System (INIS)

    Gebhardt, O.; Hermann, A.; Bart, G.; Blank, H.; Ray, I.L.F.

    1996-01-01

    In-pile grown corrosion films on different fuel rod claddings (standard Zircaloy-4, extra low tin Zircaloy (ELS), and Zr2.5Nb) have been studied using a variety of experimental techniques. The aim of the investigations was to find out common features and differences between the corrosion layers grown on zirconium alloys having different composition. Methods applied were scanning and transmission electron microscopy (SEM, TEM), electrochemical impedance spectroscopy (EIS), and electrochemical anodization. The morphological differences have been observed between the specimens that could explain the irradiation enhancement of corrosion of Zircaloy-4. The features of the compact oxide close to the oxide/metal interface have been characterized by electrochemical methods. The relationship between the thickness of this protective oxide and the overall oxide thickness has been investigated by EIS. It was found that this relation is dependent on the location of the oxide along the fuel rod and on the corrosion rate

  11. Simulating Sand Behavior through Terrain Subdivision and Particle Refinement

    Science.gov (United States)

    Clothier, M.

    2013-12-01

    their proximity to the interacting object or force with the sand. To illustrate an example, as a rover wheel moves forward and approaches a particular sand region, that region will continue to subdivide until individual sand particles are represented. Conversely, if the rover wheel moves away, previously subdivided sand regions will recombine. Thus, individual sand particles are available when an interacting force is present but stored away if there is not. As such, this technique allows for many particles to be represented without the computational complexity. We have also further generalized these subdivision regions in our sand framework into any volumetric area suitable for use in the simulation. This allows for more compact subdivision regions and has fine-tuned our framework so that more emphasis can be placed on regions of actively participating sand. We feel that this increases the framework's usefulness across scientific applications and can provide for other research opportunities within the earth and planetary sciences. Through continued collaboration with our academic partners, we continue to build upon our sand simulation framework and look for other opportunities to utilize this research.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. Study on shear properties of coral sand under cyclic simple shear condition

    Science.gov (United States)

    Ji, Wendong; Zhang, Yuting; Jin, Yafei

    2018-05-01

    In recent years, the ocean development in our country urgently needs to be accelerated. The construction of artificial coral reefs has become an important development direction. In this paper, experimental studies of simple shear and cyclic simple shear of coral sand are carried out, and the shear properties and particle breakage of coral sand are analyzed. The results show that the coral sand samples show an overall shear failure in the simple shear test, which is more accurate and effective for studying the particle breakage. The shear displacement corresponding to the peak shear stress of the simple shear test is significantly larger than that corresponding to the peak shear stress of the direct shear test. The degree of particle breakage caused by the simple shear test is significantly related to the normal stress level. The particle breakage of coral sand after the cyclic simple shear test obviously increases compared with that of the simple shear test, and universal particle breakage occurs within the whole particle size range. The increasing of the cycle-index under cyclic simple shear test results in continuous compacting of the sample, so that the envelope curve of peak shearing force increases with the accumulated shear displacement.

  17. 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

  18. 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)

  19. 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...

  20. 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)

  1. 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.

  2. 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....

  3. 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.

  4. 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...

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. 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.

  10. A study on water infiltration barriers with compacted layered soils

    International Nuclear Information System (INIS)

    Umeda, Y.; Komori, K.; Fujiwara, A.

    1993-01-01

    In shallow-ground disposal of low-level radioactive wastes, water movements due to natural processes in the soil covering the disposal facility must be properly controlled. A capillary barrier with compacted layered soils can provide an effective means of controlling water movement in the soil covering placed on a low-level radioactive waste disposal facility. An experiment was performed to determine the effectiveness of a full-scale fill as a capillary barrier. The fill used in the experiment was constructed of compacted layers of clay, fine sand, and gravel. Man-made rain was caused to fall on the surfaces of the fill to observe the infiltration of rainwater into the fill and to measure the amount of water drained from within. The experiment established the effectiveness of the capillary barrier

  11. 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

  12. Sand transportation and reverse patterns over leeward face of sand dune

    Science.gov (United States)

    Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

    2017-04-01

    Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

  13. 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

  14. 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.

  15. 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.)

  16. 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

  17. 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.

  18. 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

  19. 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.

  20. 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....

  1. 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

  2. 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.

  3. 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)

  4. 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.

  5. 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.

  6. 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. ...

  7. 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)

  8. 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.

  9. The Rheology of Acoustically Fluidized Sand

    Science.gov (United States)

    Conrad, J. W.; Melosh, J.

    2013-12-01

    The collapse of large craters and the formation of central peaks and peak rings is well modeled by numerical computer codes that incorporate the acoustic fluidization mechanism to temporarily allow the fluid-like flow of rock debris immediately after crater excavation. Furthermore, long runout landslides require a similar mechanism to explain their almost frictionless movement, which is probably also a consequence of their granular composition coupled with internal vibrations. Many different investigators have now confirmed the ability of vibrations to fluidize granular materials. Yet it still remains to fully describe the rheology of vibrated sand as a function of stress, frequency and amplitude of the vibrations in the sand itself. We constructed a rotational viscometer to quantitatively investigate the relation between the stress and strain rate in a horizontal bed of strongly vibrated sand. In addition to the macroscopic stain rate, the amplitude and frequency of the vibrations produced by a pair of pneumatic vibrators were also measured with the aid of miniaturized piezoelectric accelerometers (B&K 4393) whose output was recorded on a digital storage oscilloscope. The initial gathering of the experimental data was difficult due to granular memory, but by having the sand compacted vibrationally for 8 minutes before each run the scatter of data was reduced and we were able to obtain consistent results. Nevertheless, our major source of uncertainty was variations in strain rate from run to run. We find that vibrated sand flows like a highly non-Newtonian fluid, in which the shear strain rate is proportional to stress to a power much greater than one, where the precise power depends on the amplitude and frequency of the applied vibrations. Rapid flow occurs at stresses less than half of the static yield stress (that is, the yield stress when no vibration is applied) when strong vibrations are present. For a Newtonian fluid, such as water, the relation between

  10. 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.

  11. 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

  12. 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.)

  13. Compaction comparison testing using a modified impact soil tester and nuclear density gauge

    Energy Technology Data Exchange (ETDEWEB)

    Erchul, R.A.

    1999-07-01

    The purpose of this paper is to compare test results of a modified Impact Soil Tester (IST) on compacted soil with data obtained from the same soil using a nuclear density gauge at the US Army Corp of Engineer's Buena Vista Flood Wall project in Buena Vista, Virginia. The tests were run during construction of the earth flood wall during the summer of 1996. This comparison testing demonstrated the credibility of the procedure developed for the IST as a compacting testing device. The comparison data was obtained on a variety of soils ranging from silty sands to clays. The Flood Wall comparison compaction data for 90% Standard Proctor shows that the results of the IST as modified are consistent with the nuclear density gauge 89% of the time for all types of soil tested. However, if the soils are more cohesive than the results are consistent with the nuclear density gauge 97% of the time. In addition these comparison tests are in general agreement with comparison compaction testing using the same testing techniques and methods of compacted backfill in utility trenches conducted earlier for the Public Works Department, Chesterfield County, Virginia.

  14. Compaction comparison testing using a modified impact soil tester and nuclear density gauge

    International Nuclear Information System (INIS)

    Erchul, R.A.

    1999-01-01

    The purpose of this paper is to compare test results of a modified Impact Soil Tester (IST) on compacted soil with data obtained from the same soil using a nuclear density gauge at the US Army Corp of Engineer's Buena Vista Flood Wall project in Buena Vista, Virginia. The tests were run during construction of the earth flood wall during the summer of 1996. This comparison testing demonstrated the credibility of the procedure developed for the IST as a compacting testing device. The comparison data was obtained on a variety of soils ranging from silty sands to clays. The Flood Wall comparison compaction data for 90% Standard Proctor shows that the results of the IST as modified are consistent with the nuclear density gauge 89% of the time for all types of soil tested. However, if the soils are more cohesive than the results are consistent with the nuclear density gauge 97% of the time. In addition these comparison tests are in general agreement with comparison compaction testing using the same testing techniques and methods of compacted backfill in utility trenches conducted earlier for the Public Works Department, Chesterfield County, Virginia

  15. 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.

  16. 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.

  17. 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.

  18. 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....

  19. 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%.

  20. 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.

  1. 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.

  2. 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...

  3. 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.)

  4. 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.

  5. Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

    Directory of Open Access Journals (Sweden)

    J. Dańko

    2011-04-01

    Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

  6. 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).

  7. 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.

  8. 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.

  9. Water retention behaviour of compacted bentonites: experimental observations and constitutive model

    Directory of Open Access Journals (Sweden)

    Dieudonne Anne-Catherine

    2016-01-01

    Full Text Available Bentonite-based materials are studied as potential barriers for the geological disposal of radioactive waste. In this context, the hydro-mechanical behaviour of the engineered barrier is first characterized by free swelling conditions followed by constant volume conditions. This paper presents an experimental study conducted in order to characterize the water retention behaviour of a compacted MX-80 bentonite/sand mixture. Then, based on observations of the material double structure and the water retention mechanisms in compacted bentonites, a new water retention model is proposed. The model considers adsorbed water in the microstructure and capillary water in the aggregate-porosity. The model is calibrated and validated against the experimental data. It is used for better understanding competing effects between volume change and water uptake observed during hydration under free swelling conditions.

  10. 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.

  11. 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

  12. Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS)

    Science.gov (United States)

    Noah, M.; Vieth-Hillebrand, A.; Wilkes, H.

    2012-04-01

    The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying suspension. The released water is recycled for extraction. The fine tailings will be reclaimed as either dry or wet landscapes. [1] To produce 1 barrel of crude oil, 2 tons of oil sand and 2 - 3 tons of water (including recycled water) are required. [2] Open pit mining and the extraction of the bitumen from the oil sands create large and intense disturbances of different landscapes. The area currently disturbed by mining operations covers about 530 km2 and the area of tailing ponds surpasses 130 km2. An issue of increasing importance is the land remediation and reclamation of oil sand areas in Canada and the reconstruction of these disturbed landscapes back to working ecosystems similar to those existing prior to mining operations. An important issue in this context is the identification of oil sand-derived organic compounds in the tailings, their environmental behaviour and the resulting chances and limitations with respect to land reclamation. Furthermore the biodegradation processes that occur in the tailings and that could lead to a decrease in hazardous organic compounds are important challenges, which need to be investigated. This presentation will give a detailed overview of our compositional and quantitative characterisation of the organic matter in oil sand, unprocessed and processed mature fine tailings samples as well as in tailings sands used as part of land reclamation. The analytical characterisation is based on the extraction of the soluble organic matter, its

  13. 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.

  14. Radon diffusion in candidate soils for covering uranium mill tailings

    International Nuclear Information System (INIS)

    Silker, W.B.; Kalkwarf, D.R.

    1983-04-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by mill personnel as candidate covers for their tailings piles in order to reduce radon emission. These coefficients referred to diffusion in the total pore space of the soils. They were measured in the laboratory by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities but with moisture contents generally less than would be expected at a tailings site. An empirical equation was used to extrapolate measured coefficients to value expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands ranged from 0.004 to 0.06 cm 2 /s. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s

  15. 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.

  16. 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.

  17. Eastern Scheldt Sand, Baskarp Sand No. 15

    DEFF Research Database (Denmark)

    Andersen, A. T; Madsen, E. B.; Schaarup-Jensen, A. L.

    The present data report contains data from 13 drained triaxial tests, performed on two different sand types in the Soil Mechanics Laboratory at Aalborg University in March, 1997. Two tests have been performed on Baskarp Sand No. 15, which has already ken extensively tested in the Soil Mechanics...... Laboratory. The remaining 11 triaxial tests have ben performed on Eastern Scheldt Sand, which is a material not yet investigated at the Soil Mechanics Laboratory. In the first pari of this data report, the characteristics of the two sand types in question will be presented. Next, a description...... will described. In this connection, the procedure for preparation of the soil specimens will be presented, and the actual performance of the tests will be briefly outlined. Finally, the procedure for processing of the measurements from the laboratory in order to obtain usable data will be described. The final...

  18. 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.

  19. 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。

  20. 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%

  1. 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)

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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)

  7. 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)

  8. 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.

  9. Excess pore pressure generation due to pseudostatic tests in saturated sand

    NARCIS (Netherlands)

    Catala, M.A.

    2005-01-01

    Pile foundations are widely used, mainly to transmit structural load to an underlying stiffer soil or rock. This limit state load a certain pile can sustain without failure is known as pile ultimate bearing capacity. During design stage load-tests are performed in-situ on test piles to determine,

  10. Evaluation for swelling characteristics of buffer and backfill materials for high-level nuclear waste disposal. Influence of sand-bentonite content and cation compositions in bentonite

    International Nuclear Information System (INIS)

    Komine, Hideo; Ogata, Nobuhide

    1999-01-01

    Compacted bentonite and sand-bentonite mixture are attracting greater attention as buffer and backfill materials for disposal pits and access tunnels in the underground facilities for repositories of high-level nuclear waste. Buffer and backfill materials must have the swelling characteristics and are expected to fill up the space between these materials and surrounding ground by swelling. This role is called as 'Self-sealing'. To design the specifications, such as dry density, bentonite content and size, of buffer and backfill materials for the disposal facilities of high-level nuclear wastes described above, we must evaluate the swelling characteristics of compacted bentonite and sand-bentonite mixtures. For this purpose, this study proposed the evaluation formula for swelling characteristics of buffer and backfill materials containing bentonite. This study derived new equations for evaluating the relationship between the swelling deformation of compacted bentonite and sand-bentonite mixtures, and the swelling behavior of montmorillonite minerals, which are swelling clay minerals. This study also proposed new equations for evaluating the ion compositions of bentonite, ion concentration of pore water and the specific surface of bentonite, which significantly influence the swelling characteristics of buffer and backfill materials. The evaluation formula proposed in this study is presented by combining the above-mentioned new equations with theoretical equations, of which are the Gouy-Chapman diffuse double layer theory and the van der Waals force, of repulsive and attractive forces of montmorillonite minerals. (author)

  11. 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.

  12. 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.

  13. 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.

  14. 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)

  15. Liquid-Gas-Like Phase Transition in Sand Flow Under Microgravity

    Science.gov (United States)

    Huang, Yu; Zhu, Chongqiang; Xiang, Xiang; Mao, Wuwei

    2015-06-01

    In previous studies of granular flow, it has been found that gravity plays a compacting role, causing convection and stratification by density. However, there is a lack of research and analysis of the characteristics of different particles' motion under normal gravity contrary to microgravity. In this paper, we conduct model experiments on sand flow using a model test system based on a drop tower under microgravity, within which the characteristics and development processes of granular flow under microgravity are captured by high-speed cameras. The configurations of granular flow are simulated using a modified MPS (moving particle simulation), which is a mesh-free, pure Lagrangian method. Moreover, liquid-gas-like phase transitions in the sand flow under microgravity, including the transitions to "escaped", "jumping", and "scattered" particles are highlighted, and their effects on the weakening of shear resistance, enhancement of fluidization, and changes in particle-wall and particle-particle contact mode are analyzed. This study could help explain the surface geology evolution of small solar bodies and elucidate the nature of granular interaction.

  16. 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.

  17. Evaluation of the shrinkage and creep of medium strength self compacting concrete

    Science.gov (United States)

    De La Cruz, C. J.; Ramos, G.; Hurtado, W. A.

    2017-02-01

    The difference between self compacting concrete (SCC) and conventional concrete (CC) is in fresh state, is the high fluidity at first and the need for vibration at second, but in hardened state, both concretes must comply with the resistance specified, in addition to securing the safety and functionality for which it was designed. This article describes the tests and results for shrinkage and creep at some medium strength Self Compacting Concrete with added sand (SCC-MSs) and two types of cement. The research was conducted at the Laboratorio de Tecnología de Estructuras (LTE) of the Universitat Politécnica de Catalunya (UPC), in dosages of 200 liters; with the idea of evaluating the effectiveness of implementation of these new concretes at elements designed with conventional concrete (CCs).

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. Evaluation of Load-Displacement Relationships for Non-Slender Monopiles in Sand

    DEFF Research Database (Denmark)

    Sørensen, Søren Peder Hyldal; Møller, M.; Brødbæk, K. T.

    pipe piles subjected to lateral loads at a given vertical eccentricity. The piles are heavily instrumented with strain gauges in order to obtain p-y curves and bending moment distributions along the piles. In order to minimise scale effects the tests are successfully carried out in a pressure tank...... at varying stress levels. The tests are evaluated with the following main findings: The lateral pile deflection consists primarily of rotation as a rigid object; normalised load-displacement relationships indicate that the lateral load is proportional to the embedded length squared and the pile diameter......Monopiles are an often used foundation concept for offshore wind turbine converters. These piles are highly subjected to lateral loads and 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...

  3. Microscopic analysis of irradiated AGR-1 coated particle fuel compacts

    Energy Technology Data Exchange (ETDEWEB)

    Ploger, Scott A., E-mail: scott.ploger@inl.gov [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-3855 (United States); Demkowicz, Paul A. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-3855 (United States); Hunn, John D.; Kehn, Jay S. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6093 (United States)

    2014-05-01

    The AGR-1 experiment involved irradiation of 72 TRISO-coated particle fuel compacts to a peak compact-average burnup of 19.5% FIMA with no in-pile failures observed out of 3 × 10{sup 5} total particles. Irradiated AGR-1 fuel compacts have been cross-sectioned and analyzed with optical microscopy to characterize kernel, buffer, and coating behavior. Six compacts have been examined, spanning a range of irradiation conditions (burnup, fast fluence, and irradiation temperature) and including all four TRISO coating variations irradiated in the AGR-1 experiment. The cylindrical specimens were sectioned both transversely and longitudinally, then polished to expose from 36 to 79 individual particles near midplane on each mount. The analysis focused primarily on kernel swelling and porosity, buffer densification and fracturing, buffer–IPyC debonding, and fractures in the IPyC and SiC layers. Characteristic morphologies have been identified, 981 particles have been classified, and spatial distributions of particle types have been mapped. No significant spatial patterns were discovered in these cross sections. However, some trends were found between morphological types and certain behavioral aspects. Buffer fractures were found in 23% of the particles, and these fractures often resulted in unconstrained kernel protrusion into the open cavities. Fractured buffers and buffers that stayed bonded to IPyC layers appear related to larger pore size in kernels. Buffer–IPyC interface integrity evidently factored into initiation of rare IPyC fractures. Fractures through part of the SiC layer were found in only four classified particles, all in conjunction with IPyC–SiC debonding. Compiled results suggest that the deliberate coating fabrication variations influenced the frequencies of IPyC fractures and IPyC–SiC debonds.

  4. Submarine sand ridges and sand waves in the eastern part of the China Sea

    Science.gov (United States)

    Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

    2016-04-01

    Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

  5. 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

  6. 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.

  7. Neutron radiation shielding properties of polymer incorporated self compacting concrete mixes.

    Science.gov (United States)

    Malkapur, Santhosh M; Divakar, L; Narasimhan, Mattur C; Karkera, Narayana B; Goverdhan, P; Sathian, V; Prasad, N K

    2017-07-01

    In this work, the neutron radiation shielding characteristics of a class of novel polymer-incorporated self-compacting concrete (PISCC) mixes are evaluated. Pulverized high density polyethylene (HDPE) material was used, at three different reference volumes, as a partial replacement to river sand in conventional concrete mixes. By such partial replacement of sand with polymer, additional hydrogen contents are incorporated in these concrete mixes and their effect on the neutron radiation shielding properties are studied. It has been observed from the initial set of experiments that there is a definite trend of reductions in the neutron flux and dose transmission factor values in these PISCC mixes vis-à-vis ordinary concrete mix. Also, the fact that quite similar enhanced shielding results are recorded even when reprocessed HDPE material is used in lieu of the virgin HDPE attracts further attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. 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

  14. Cost reducing factors in effective pipeline piling structure design and construction in Alberta's thermal SAGD gathering pipeline systems

    Energy Technology Data Exchange (ETDEWEB)

    Farrokhzad, M.A. [IMV Projects, Calgary, AB (Canada)

    2008-10-15

    Oil sands steam assisted gravity drainage (SAGD) gathering pipeline systems are typically arranged so that above-ground steam pipeline and production pipelines lay next to each other on the same steel structure. Longitudinal and lateral loads build up in the pipeline supports, and the loads are consistently changing until pipeline temperatures reach a steady state condition. SAGD pipelines are required to have enough flexibility to absorb thermal expansion or contraction movements. However, most pipeline engineers only consider upper and lower temperature limits in the design of steel structures and pilings. This paper examined the effect of considering both the thermal gradient and time factor in designing supports for pipelines. The study examined how the factors impacted on standard load calculations and pile sizings. Sixteen stress analysis models for steam and production lines were prepared and designated thermal gradients were introduced to each model. Longitudinal and lateral loads caused by thermal gradient movements were calculated for all supports. The models were analyzed and absolute values for longitudinal and lateral loads were recorded. Results of the study showed that engineers do not necessarily need to rely on maximum temperatures as the condition that results in maximum longitudinal and lateral loads on supports. It was concluded that costs related to pipeline construction can be significantly reduced by considering the effects of thermal gradients in stress analyses and load calculations. 5 refs., 14 figs.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. An Integrated Rock Typing Approach for Unraveling the Reservoir Heterogeneity of Tight Sands in the Whicher Range Field of Perth Basin, Western Australia

    DEFF Research Database (Denmark)

    Ilkhchi, Rahim Kadkhodaie; Rezaee, Reza; Harami, Reza Moussavi

    2014-01-01

    Tight gas sands in Whicher Range Field of Perth Basin show large heterogeneity in reservoir characteristics and production behavior related to depositional and diagenetic features. Diagenetic events (compaction and cementation) have severely affected the pore system. In order to investigate...... the petrophysical characteristics, reservoir sandstone facies were correlated with core porosity and permeability and their equivalent well log responses to describe hydraulic flow units and electrofacies, respectively. Thus, very tight, tight, and sub-tight sands were differentiated. To reveal the relationship...... between pore system properties and depositional and diagenetic characteristics in each sand type, reservoir rock types were extracted. The identified reservoir rock types are in fact a reflection of internal reservoir heterogeneity related to pore system properties. All reservoir rock types...

  20. 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.

  1. 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.

  2. 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.

  3. Fontainebleau Sand

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    2006-01-01

    The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand.......The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand....

  4. 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...

  5. 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

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.)

  12. 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.

  13. 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.)

  14. 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 (

  15. 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...

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. 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.)