Les Inscriptions à la Bibliothèque sont ouvertes en
ligne via le site: https://biblio.enp.edu.dz
Les Réinscriptions se font à :
• La Bibliothèque Annexe pour les étudiants en
2ème Année CPST
• La Bibliothèque Centrale pour les étudiants en Spécialités
A partir de cette page vous pouvez :
| Retourner au premier écran avec les recherches... |
Journal of geotechnical and geoenvironmental engineering (ASCE) |
Dépouillements
Ajouter le résultat dans votre panierStrain influence diagrams for settlement estimation of both isolated and multiple footings in sand / Junhwan Lee in Journal of geotechnical and geoenvironmental engineering, Vol. 134 N°4 (Avril 2008)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 417–427
Titre : Strain influence diagrams for settlement estimation of both isolated and multiple footings in sand Type de document : texte imprimé Auteurs : Junhwan Lee, Auteur ; Jongwan Eun, Auteur ; Monica Prezzi, Auteur Année de publication : 2008 Article en page(s) : pp. 417–427 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Footings Settlement Strains Finite element method Sand Résumé : Most of the existing methods for estimating settlements of footings in sand have been developed for either isolated square footings or for strip footings. The literature contains limited information on settlement analysis of rectangular footings, and, as a result, there is no way to accurately account for the effect of the footing length-to-width ratio on settlement. Additionally, no practical method exists for considering the interaction between neighboring footings in settlement estimates. In this paper, we use Schmertmann’s framework to propose a method of settlement estimation that takes full account of both the footing length-to-width ratio and the proximity of neighboring footings. Three-dimensional nonlinear finite element analyses were performed for various multiple footing configurations. Plate load tests were performed in sands using both a single plate and two plates separated by various distances. The numerical and experimental results indicate that the shape of the footing (expressed through its length-to-width ratio) and the proximity of neighboring footings affect two parameters of the strain influence diagram (which is the basis for the settlement estimation method): the depth to the peak influence factor Izp and the depth of the strain influence zone. We propose new strain influence diagrams for estimation of settlement under these more general conditions. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2841 [...] [article] Strain influence diagrams for settlement estimation of both isolated and multiple footings in sand [texte imprimé] / Junhwan Lee, Auteur ; Jongwan Eun, Auteur ; Monica Prezzi, Auteur . - 2008 . - pp. 417–427.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 417–427
Mots-clés : Footings Settlement Strains Finite element method Sand Résumé : Most of the existing methods for estimating settlements of footings in sand have been developed for either isolated square footings or for strip footings. The literature contains limited information on settlement analysis of rectangular footings, and, as a result, there is no way to accurately account for the effect of the footing length-to-width ratio on settlement. Additionally, no practical method exists for considering the interaction between neighboring footings in settlement estimates. In this paper, we use Schmertmann’s framework to propose a method of settlement estimation that takes full account of both the footing length-to-width ratio and the proximity of neighboring footings. Three-dimensional nonlinear finite element analyses were performed for various multiple footing configurations. Plate load tests were performed in sands using both a single plate and two plates separated by various distances. The numerical and experimental results indicate that the shape of the footing (expressed through its length-to-width ratio) and the proximity of neighboring footings affect two parameters of the strain influence diagram (which is the basis for the settlement estimation method): the depth to the peak influence factor Izp and the depth of the strain influence zone. We propose new strain influence diagrams for estimation of settlement under these more general conditions. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2841 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 428–436
Titre : Behavior of slender piles subject to free-field lateral soil movement Type de document : texte imprimé Auteurs : David J. White, Auteur ; Mark J. Thompson, Auteur ; Muhannad T. Suleiman, Auteur Année de publication : 2008 Article en page(s) : pp. 428–436 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Pile load tests Slope stability Interactions Résumé : Soil movements associated with slope instability induce shear forces and bending moments in stabilizing piles that vary with the buildup of passive pile resistance. For such free-field lateral soil movements, stress development along the pile element is a function of the relative displacement between the soil and the pile. To investigate the effects of relative soil-pile displacement on pile response, large-scale load tests were performed on relatively slender, drilled, composite pile elements (cementitious grout with centered steel reinforcing bar). The piles were installed through a shear box into stable soil and then loaded by lateral translation of the shear box. The load tests included two pile diameters (nominal 115 and 178mm ) and three cohesive soil types (loess, glacial till, and weathered shale). Instrumentation indicated the relative soil-pile displacements and the pile response to the loads that developed along the piles. Using the experimental results, an analysis approach was evaluated using soil p-y curves derived from laboratory undrained shear strength tests. The test piles and analyses helped characterize behavioral stages of the composite pile elements at loads up to pile section failure and also provided a unique dataset to evaluate the lateral response analysis method for its applicability to slender piles. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2842 [...] [article] Behavior of slender piles subject to free-field lateral soil movement [texte imprimé] / David J. White, Auteur ; Mark J. Thompson, Auteur ; Muhannad T. Suleiman, Auteur . - 2008 . - pp. 428–436.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 428–436
Mots-clés : Pile load tests Slope stability Interactions Résumé : Soil movements associated with slope instability induce shear forces and bending moments in stabilizing piles that vary with the buildup of passive pile resistance. For such free-field lateral soil movements, stress development along the pile element is a function of the relative displacement between the soil and the pile. To investigate the effects of relative soil-pile displacement on pile response, large-scale load tests were performed on relatively slender, drilled, composite pile elements (cementitious grout with centered steel reinforcing bar). The piles were installed through a shear box into stable soil and then loaded by lateral translation of the shear box. The load tests included two pile diameters (nominal 115 and 178mm ) and three cohesive soil types (loess, glacial till, and weathered shale). Instrumentation indicated the relative soil-pile displacements and the pile response to the loads that developed along the piles. Using the experimental results, an analysis approach was evaluated using soil p-y curves derived from laboratory undrained shear strength tests. The test piles and analyses helped characterize behavioral stages of the composite pile elements at loads up to pile section failure and also provided a unique dataset to evaluate the lateral response analysis method for its applicability to slender piles. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2842 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 437–444
Titre : Earth pressure due to vibratory compaction Type de document : texte imprimé Auteurs : Tsang-Jiang Chen, Auteur ; Yung-Show Fang, Auteur Année de publication : 2008 Article en page(s) : pp. 437–444 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Soil compaction Earth pressure Model tests Retaining walls Sand Résumé : This paper presents experimental data on the variation of lateral earth pressure against a nonyielding retaining wall due to soil filling and vibratory compaction. Air-dry Ottawa sand was placed in five lifts and each lift was compacted to achieve a relative density of 75%. Each compacted lift was 0.3m thick. The instrumented nonyielding wall facility at National Chiao Tung University in Taiwan was used to investigate the effects of vibratory compaction on the change of stresses at the soil-wall interface. Based on the experimental data it has been found that, for a compacted backfill, the vertical overburden pressure can also be properly estimated with the traditional equation σv=γz . The effects of vibratory compaction on the vertical pressure in the backfill were insignificant. On the vertical nonyielding wall, extra horizontal earth pressure was induced by vibratory compaction. After compaction, the lateral earth pressure measured near the top of the wall was almost identical to the passive Rankine pressure. It is concluded that as the cyclic compacting stress applied on the surface of the backfill exceeded the ultimate bearing capacity of the foundation soil, a shear failure zone would develop in the uppermost layer of the backfill. For a soil element under lateral compression, the vertical overburden pressure remained unchanged, and the horizontal stress increased to the Rankine passive pressure. It was also found that the compaction-influenced zone rose with the rising compaction surface. The horizontal earth pressure measured below the compaction-influenced zone converged to the Jaky state of stress. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2843 [...] [article] Earth pressure due to vibratory compaction [texte imprimé] / Tsang-Jiang Chen, Auteur ; Yung-Show Fang, Auteur . - 2008 . - pp. 437–444.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 437–444
Mots-clés : Soil compaction Earth pressure Model tests Retaining walls Sand Résumé : This paper presents experimental data on the variation of lateral earth pressure against a nonyielding retaining wall due to soil filling and vibratory compaction. Air-dry Ottawa sand was placed in five lifts and each lift was compacted to achieve a relative density of 75%. Each compacted lift was 0.3m thick. The instrumented nonyielding wall facility at National Chiao Tung University in Taiwan was used to investigate the effects of vibratory compaction on the change of stresses at the soil-wall interface. Based on the experimental data it has been found that, for a compacted backfill, the vertical overburden pressure can also be properly estimated with the traditional equation σv=γz . The effects of vibratory compaction on the vertical pressure in the backfill were insignificant. On the vertical nonyielding wall, extra horizontal earth pressure was induced by vibratory compaction. After compaction, the lateral earth pressure measured near the top of the wall was almost identical to the passive Rankine pressure. It is concluded that as the cyclic compacting stress applied on the surface of the backfill exceeded the ultimate bearing capacity of the foundation soil, a shear failure zone would develop in the uppermost layer of the backfill. For a soil element under lateral compression, the vertical overburden pressure remained unchanged, and the horizontal stress increased to the Rankine passive pressure. It was also found that the compaction-influenced zone rose with the rising compaction surface. The horizontal earth pressure measured below the compaction-influenced zone converged to the Jaky state of stress. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2843 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 445–458
Titre : Performance of sheet pile wall in peat Type de document : texte imprimé Auteurs : Yong Tan, Auteur ; Samuel G. Paikowsky, Auteur Année de publication : 2008 Article en page(s) : pp. 445–458 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Earth pressure Sheet pile Instrumentation Finite element method Retaining walls Waterfront structures Résumé : To study the performance of sheet pile wall in peat during roadway construction, a long-term instrumentation program was conducted over a period of two years, measuring total lateral earth pressures, sheet pile deflections, soil movements, and water table level variances during construction. The analysis of field data indicated: (1) The earth pressure distribution in peat matched well with the classic Rankine earth pressure; (2) the expected long-term postconstruction sheet pile movement due to the creep behavior of peat was not observed; (3) fully passive earth pressure in peat was mobilized once the maximum measured sheet pile deflection exceeded 0.8% of sheet pile length; and (4) arching effect due to the protruding cross section of sheet pile caused pressure differences of 3–10kPa between the inside web and outside web of the sheeting. Then, all the construction stages were continuously modeled by finite-element method and the calculated results were compared with the field measurements. The comparisons showed that the calculated results were consistent with the field data and provided reasonable explanations and helpful insights to understand soil–structure interaction mechanism. Finally, some conclusions and suggestions for sheet pile design and construction in peat were reached. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2844 [...] [article] Performance of sheet pile wall in peat [texte imprimé] / Yong Tan, Auteur ; Samuel G. Paikowsky, Auteur . - 2008 . - pp. 445–458.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 445–458
Mots-clés : Earth pressure Sheet pile Instrumentation Finite element method Retaining walls Waterfront structures Résumé : To study the performance of sheet pile wall in peat during roadway construction, a long-term instrumentation program was conducted over a period of two years, measuring total lateral earth pressures, sheet pile deflections, soil movements, and water table level variances during construction. The analysis of field data indicated: (1) The earth pressure distribution in peat matched well with the classic Rankine earth pressure; (2) the expected long-term postconstruction sheet pile movement due to the creep behavior of peat was not observed; (3) fully passive earth pressure in peat was mobilized once the maximum measured sheet pile deflection exceeded 0.8% of sheet pile length; and (4) arching effect due to the protruding cross section of sheet pile caused pressure differences of 3–10kPa between the inside web and outside web of the sheeting. Then, all the construction stages were continuously modeled by finite-element method and the calculated results were compared with the field measurements. The comparisons showed that the calculated results were consistent with the field data and provided reasonable explanations and helpful insights to understand soil–structure interaction mechanism. Finally, some conclusions and suggestions for sheet pile design and construction in peat were reached. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2844 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 459–469
Titre : Effect of progressive failure on measured shear strength of geomembrane/GCL interface Type de document : texte imprimé Auteurs : Fox, Patrick J., Auteur ; Robert H. Kim, Auteur Année de publication : 2008 Article en page(s) : pp. 459–469 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Shear strength Geosynthetics Progressive failure Numerical analysis Résumé : This paper presents experimental data and numerical modeling results that illustrate the effects of progressive failure on the measured shear strength of a textured geomembrane/geosynthetic clay liner (GMX/GCL) interface. Large direct shear tests were conducted using different specimen gripping/clamping systems to isolate the effects of progressive failure. These tests indicate that progressive failure causes a reduction in measured peak shear strength, an increase in the displacement at peak, an increase in large displacement shear strength, and significant distortion of the shear stress–displacement relationship. A numerical model was developed to simulate progressive failure of a GMX/GCL interface. Measured and simulated shear stress–displacement relationships are in good-to-excellent agreement at four normal stress levels. The model was then used to investigate mechanisms of progressive interface failure and factors that control its significance. The results indicate that accurate measurements of shear stress–displacement behavior and strength are obtained when gripping surfaces prevent slippage of the test specimen and the intended failure surface has the lowest shear resistance of all possible sliding surfaces. The use of proper gripping surfaces is expected to reduce difficulties in test data interpretation and to increase the accuracy and reproducibility of test results. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2845 [...] [article] Effect of progressive failure on measured shear strength of geomembrane/GCL interface [texte imprimé] / Fox, Patrick J., Auteur ; Robert H. Kim, Auteur . - 2008 . - pp. 459–469.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 459–469
Mots-clés : Shear strength Geosynthetics Progressive failure Numerical analysis Résumé : This paper presents experimental data and numerical modeling results that illustrate the effects of progressive failure on the measured shear strength of a textured geomembrane/geosynthetic clay liner (GMX/GCL) interface. Large direct shear tests were conducted using different specimen gripping/clamping systems to isolate the effects of progressive failure. These tests indicate that progressive failure causes a reduction in measured peak shear strength, an increase in the displacement at peak, an increase in large displacement shear strength, and significant distortion of the shear stress–displacement relationship. A numerical model was developed to simulate progressive failure of a GMX/GCL interface. Measured and simulated shear stress–displacement relationships are in good-to-excellent agreement at four normal stress levels. The model was then used to investigate mechanisms of progressive interface failure and factors that control its significance. The results indicate that accurate measurements of shear stress–displacement behavior and strength are obtained when gripping surfaces prevent slippage of the test specimen and the intended failure surface has the lowest shear resistance of all possible sliding surfaces. The use of proper gripping surfaces is expected to reduce difficulties in test data interpretation and to increase the accuracy and reproducibility of test results. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2845 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 470–486
Titre : Comparison of field data and water-balance predictions for a capillary barrier cover Type de document : texte imprimé Auteurs : A. S. Ogorzalek, Auteur ; G. L. Bohnhoff, Auteur ; C. D. Shackelford, Auteur Année de publication : 2008 Article en page(s) : pp. 470–486 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Unsaturated flow Water balance Coverings Barriers Containment Résumé : Predictions of surface runoff (R) , evapotranspiration (ET), soil–water storage (S) , and percolation obtained using three numerical codes (LEACHM, HYDRUS, and UNSAT-H) employed to simulate the hydrology of water-balance covers are compared to measured water-balance data from a lysimeter used to monitor a capillary barrier cover profile in a subhumid climate. All of the codes captured the seasonal variations in water-balance quantities observed in the field. LEACHM and HYDRUS predicted total R during the monitoring period with reasonable accuracy (within 18mm using general mean parameters), but the timing of predicted and observed R events was different. In contrast, UNSAT-H consistently overpredicted R by at least 239mm . Evapotranspiration was predicted reliably (within 60mm ) with all three codes when data from the first year were excluded. However, all three codes overpredicted ET in late winter and early spring, when snowmelt was occurring and S was accumulating in the field. Consequently, S generally was underpredicted by all three codes. Predicted and measured percolation were in good agreement (within 1mm∕year ), except during the first year. Results of the comparison indicate that cover modelers should scrutinize runoff predictions for reasonableness and carefully account for snow accumulation, snow melt, and ET during snow cover. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2847 [...] [article] Comparison of field data and water-balance predictions for a capillary barrier cover [texte imprimé] / A. S. Ogorzalek, Auteur ; G. L. Bohnhoff, Auteur ; C. D. Shackelford, Auteur . - 2008 . - pp. 470–486.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 470–486
Mots-clés : Unsaturated flow Water balance Coverings Barriers Containment Résumé : Predictions of surface runoff (R) , evapotranspiration (ET), soil–water storage (S) , and percolation obtained using three numerical codes (LEACHM, HYDRUS, and UNSAT-H) employed to simulate the hydrology of water-balance covers are compared to measured water-balance data from a lysimeter used to monitor a capillary barrier cover profile in a subhumid climate. All of the codes captured the seasonal variations in water-balance quantities observed in the field. LEACHM and HYDRUS predicted total R during the monitoring period with reasonable accuracy (within 18mm using general mean parameters), but the timing of predicted and observed R events was different. In contrast, UNSAT-H consistently overpredicted R by at least 239mm . Evapotranspiration was predicted reliably (within 60mm ) with all three codes when data from the first year were excluded. However, all three codes overpredicted ET in late winter and early spring, when snowmelt was occurring and S was accumulating in the field. Consequently, S generally was underpredicted by all three codes. Predicted and measured percolation were in good agreement (within 1mm∕year ), except during the first year. Results of the comparison indicate that cover modelers should scrutinize runoff predictions for reasonableness and carefully account for snow accumulation, snow melt, and ET during snow cover. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2847 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 487–496
Titre : Near-infrared spectroscopy for in situ monitoring of geoenvironment Type de document : texte imprimé Auteurs : Masoud Ghandehari, Auteur ; Konstantinos Kostarelos, Auteur ; Kai-Chung Cheng, Auteur Année de publication : 2008 Article en page(s) : pp. 487–496 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : In situ tests Monitoring Fiber optics Hydrocarbons Absorption Liquids Résumé : This paper demonstrates the usefulness of near-infrared optical fiber analysis for sensing moisture and liquid hydrocarbons in soil. Through experiments we have carried out sensing probes which have been developed, comprising optical fibers that use the evanescent field of the guided energy. The movement of water through dry sand was simulated in the laboratory and the sensors were used in situ to measure the variation of soil moisture in real time. A similar experiment simulated the movement of an organic liquid (mineral oil) through water-saturated sand, and the sensors were used in situ to monitor the hydrocarbon movement. We found that a hydrophobic polymer-coated waveguide can amplify the hydrocarbon signal while minimizing that of water, making it possible to detect a dissolved hydrocarbon. Tests show that the second derivative transform of the absorption spectra could be used to distinguish classes of hydrocarbons. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2848 [...] [article] Near-infrared spectroscopy for in situ monitoring of geoenvironment [texte imprimé] / Masoud Ghandehari, Auteur ; Konstantinos Kostarelos, Auteur ; Kai-Chung Cheng, Auteur . - 2008 . - pp. 487–496.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 487–496
Mots-clés : In situ tests Monitoring Fiber optics Hydrocarbons Absorption Liquids Résumé : This paper demonstrates the usefulness of near-infrared optical fiber analysis for sensing moisture and liquid hydrocarbons in soil. Through experiments we have carried out sensing probes which have been developed, comprising optical fibers that use the evanescent field of the guided energy. The movement of water through dry sand was simulated in the laboratory and the sensors were used in situ to measure the variation of soil moisture in real time. A similar experiment simulated the movement of an organic liquid (mineral oil) through water-saturated sand, and the sensors were used in situ to monitor the hydrocarbon movement. We found that a hydrophobic polymer-coated waveguide can amplify the hydrocarbon signal while minimizing that of water, making it possible to detect a dissolved hydrocarbon. Tests show that the second derivative transform of the absorption spectra could be used to distinguish classes of hydrocarbons. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2848 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 497–508
Titre : Theoretical equations on hydraulic conductivities of bentonite-based buffer and backfill for underground disposal of radioactive wastes Type de document : texte imprimé Auteurs : Hideo Komine, Auteur Année de publication : 2008 Article en page(s) : pp. 497–508 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Hydraulic conductivity Radioactive wastes Waste disposal Expansive soils Microscopy Swelling Backfills Résumé : Compacted bentonite and sand-bentonite mixtures are sought as buffer and backfill materials for high-level radioactive waste disposal facilities because they have very low permeability. To establish specifications such as the dry density and sand-bentonite mass ratio for buffer and backfill materials, we must quantitatively evaluate a material’s hydraulic conductivities. This study presents theoretical new equations for evaluating the hydraulic conductivity of compacted bentonites and sand-bentonite mixtures. New equations are proposed for evaluating the flow velocity of interlayer water between two montmorillonite parallel-plate layers considering the swelling behaviors of montmorillonite. Furthermore, a prediction method for hydraulic conductivity of compacted bentonite and sand-bentonite mixtures is presented by combining new equations with previous equations for evaluating swelling behavior of montmorillonite in bentonite. The applicability of this method is clarified by comparing predicted results with experimental data reported by previous research on hydraulic conductivities of compacted bentonites and sand-bentonite mixtures. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2849 [...] [article] Theoretical equations on hydraulic conductivities of bentonite-based buffer and backfill for underground disposal of radioactive wastes [texte imprimé] / Hideo Komine, Auteur . - 2008 . - pp. 497–508.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 497–508
Mots-clés : Hydraulic conductivity Radioactive wastes Waste disposal Expansive soils Microscopy Swelling Backfills Résumé : Compacted bentonite and sand-bentonite mixtures are sought as buffer and backfill materials for high-level radioactive waste disposal facilities because they have very low permeability. To establish specifications such as the dry density and sand-bentonite mass ratio for buffer and backfill materials, we must quantitatively evaluate a material’s hydraulic conductivities. This study presents theoretical new equations for evaluating the hydraulic conductivity of compacted bentonites and sand-bentonite mixtures. New equations are proposed for evaluating the flow velocity of interlayer water between two montmorillonite parallel-plate layers considering the swelling behaviors of montmorillonite. Furthermore, a prediction method for hydraulic conductivity of compacted bentonite and sand-bentonite mixtures is presented by combining new equations with previous equations for evaluating swelling behavior of montmorillonite in bentonite. The applicability of this method is clarified by comparing predicted results with experimental data reported by previous research on hydraulic conductivities of compacted bentonites and sand-bentonite mixtures. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2849 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 509–518
Titre : Metal transport parameters of a gneiss saprolitic silty soil for liner design Type de document : texte imprimé Auteurs : Monica Machado Stuermer, Auteur ; Maria Eugenia Gimenez Boscov, Auteur ; Elisabeth de Oliveira, Auteur Année de publication : 2008 Article en page(s) : pp. 509–518 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Residual soils Compacted soils Sorption Diffusion Heavy metals Laboratory tests Silts Parameters Résumé : Diffusion coefficients and retardation factors of two metal cations ( Cd2+ and Pb2+ ) were measured for a compacted Brazilian saprolitic soil derived from gneiss, aiming to assess its geoenvironmental performance as a liner for waste disposal sites. This soil occurs extensively all over the country in very thick layers, but has not been used in liners because of its hydraulic conductivity, higher than 10−9m/s when compacted at optimum water content of standard Proctor energy, but which can be reduced by means of appropriate compaction techniques or additives. Batch, column, and diffusion tests were carried out with monospecies synthetic solutions at pH 1, 3, and 5.5. Measured diffusion coefficients varied between 0.5 and 4×10−10m2/s . Retardation factors show that cadmium, a very mobile cation, is not adsorbed at pH 1 but is significantly retained at pH 3 and pH 5.5, whereas lead is retained at all tested pH values though slightly at pH 1. Estimated retardation factors from batch tests were 1.3–2.3 times those resulting from column tests and at its highest when obtained by diffusion tests; whereas batch tests allow a more complete exposure of the soil grains to the solution, time-dependent nonspecific adsorption may take longer to occur. The importance of contact time was observed and should be considered in further investigations. Its significant retention of metals suggests a promising utilization of this soil as a bottom liner for wastes landfills. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2850 [...] [article] Metal transport parameters of a gneiss saprolitic silty soil for liner design [texte imprimé] / Monica Machado Stuermer, Auteur ; Maria Eugenia Gimenez Boscov, Auteur ; Elisabeth de Oliveira, Auteur . - 2008 . - pp. 509–518.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 509–518
Mots-clés : Residual soils Compacted soils Sorption Diffusion Heavy metals Laboratory tests Silts Parameters Résumé : Diffusion coefficients and retardation factors of two metal cations ( Cd2+ and Pb2+ ) were measured for a compacted Brazilian saprolitic soil derived from gneiss, aiming to assess its geoenvironmental performance as a liner for waste disposal sites. This soil occurs extensively all over the country in very thick layers, but has not been used in liners because of its hydraulic conductivity, higher than 10−9m/s when compacted at optimum water content of standard Proctor energy, but which can be reduced by means of appropriate compaction techniques or additives. Batch, column, and diffusion tests were carried out with monospecies synthetic solutions at pH 1, 3, and 5.5. Measured diffusion coefficients varied between 0.5 and 4×10−10m2/s . Retardation factors show that cadmium, a very mobile cation, is not adsorbed at pH 1 but is significantly retained at pH 3 and pH 5.5, whereas lead is retained at all tested pH values though slightly at pH 1. Estimated retardation factors from batch tests were 1.3–2.3 times those resulting from column tests and at its highest when obtained by diffusion tests; whereas batch tests allow a more complete exposure of the soil grains to the solution, time-dependent nonspecific adsorption may take longer to occur. The importance of contact time was observed and should be considered in further investigations. Its significant retention of metals suggests a promising utilization of this soil as a bottom liner for wastes landfills. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2850 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 519–530
Titre : Coupled use of cone tip resistance and small strain shear modulus to assess liquefaction potential Type de document : texte imprimé Auteurs : Debasis Roy, Auteur Année de publication : 2008 Article en page(s) : pp. 519–530 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Cone penetration Shear waves Velocity Compression Sampling Liquefaction Earthquakes Résumé : Resistance against earthquake-related liquefaction is usually assessed using relationships between an index of soil strength such as normalized cone tip resistance and the cyclic resistance ratio (CRR) developed from observed field performance. The alternative approach based on laboratory testing is rarely used, mainly because of the apprehension that laboratory results may not reflect field behavior since the quality of laboratory data is often compromised by sampling disturbance. In this study, a database of laboratory data obtained mainly from cyclic testing of frozen (undisturbed) samples and in situ index measurements from near sampling locations comprised of cone tip resistance, qc , and shear wave velocity, Vs , have been assembled. These data indicate that neither normalized cone tip resistance nor normalized shear wave velocity individually correlate well with laboratory-measured CRR. However, the ratio of qc to the small strain shear modulus, G0 , relates reasonably with CRR via separate correlations depending on geologic age. The derived qc∕G0 -CRR relationships were also found to be consistent with earthquake field-performance case histories. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2851 [...] [article] Coupled use of cone tip resistance and small strain shear modulus to assess liquefaction potential [texte imprimé] / Debasis Roy, Auteur . - 2008 . - pp. 519–530.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 519–530
Mots-clés : Cone penetration Shear waves Velocity Compression Sampling Liquefaction Earthquakes Résumé : Resistance against earthquake-related liquefaction is usually assessed using relationships between an index of soil strength such as normalized cone tip resistance and the cyclic resistance ratio (CRR) developed from observed field performance. The alternative approach based on laboratory testing is rarely used, mainly because of the apprehension that laboratory results may not reflect field behavior since the quality of laboratory data is often compromised by sampling disturbance. In this study, a database of laboratory data obtained mainly from cyclic testing of frozen (undisturbed) samples and in situ index measurements from near sampling locations comprised of cone tip resistance, qc , and shear wave velocity, Vs , have been assembled. These data indicate that neither normalized cone tip resistance nor normalized shear wave velocity individually correlate well with laboratory-measured CRR. However, the ratio of qc to the small strain shear modulus, G0 , relates reasonably with CRR via separate correlations depending on geologic age. The derived qc∕G0 -CRR relationships were also found to be consistent with earthquake field-performance case histories. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2851 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 531–540
Titre : Uplift performance of transmission tower foundations embedded in clay Type de document : texte imprimé Auteurs : M. J. Rattley, Auteur ; D. J. Richards, Auteur ; B. M. Lehane, Auteur Année de publication : 2008 Article en page(s) : pp. 531–540 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Shallow foundations Suction Centrifuge model Clays Electric transmission structures Towers Résumé : The contribution to the uplift stiffness and capacity provided by the clay beneath the base of shallow footings typical in configuration to those employed to support high voltage electricity transmission towers is examined. Pore pressures developed at the base of appropriately scaled footings founded on clay were measured over a wide range of uplift rates in a geotechnical centrifuge. These measurements, coupled with data from tests on identical footings founded on sand, are used to provide insights into the influence of uplift rate on the failure mechanism and footing capacity. Data from a series of undrained triaxial extension tests, conducted over a range of strain rates, are presented and these data combined with finite element back-analyses of the centrifuge uplift tests are used to provide designers with a means of assessing the capacity and load–displacement response of footings on clay subjected to high rates of uplift in service. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2853 [...] [article] Uplift performance of transmission tower foundations embedded in clay [texte imprimé] / M. J. Rattley, Auteur ; D. J. Richards, Auteur ; B. M. Lehane, Auteur . - 2008 . - pp. 531–540.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 531–540
Mots-clés : Shallow foundations Suction Centrifuge model Clays Electric transmission structures Towers Résumé : The contribution to the uplift stiffness and capacity provided by the clay beneath the base of shallow footings typical in configuration to those employed to support high voltage electricity transmission towers is examined. Pore pressures developed at the base of appropriately scaled footings founded on clay were measured over a wide range of uplift rates in a geotechnical centrifuge. These measurements, coupled with data from tests on identical footings founded on sand, are used to provide insights into the influence of uplift rate on the failure mechanism and footing capacity. Data from a series of undrained triaxial extension tests, conducted over a range of strain rates, are presented and these data combined with finite element back-analyses of the centrifuge uplift tests are used to provide designers with a means of assessing the capacity and load–displacement response of footings on clay subjected to high rates of uplift in service. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2853 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 541–546
Titre : Model tests on discontinuities in subsurface barrier installed by the vibrating beam method Type de document : texte imprimé Auteurs : W. Wu, Auteur ; F. Aschauer, Auteur ; G. Reiser, Auteur Année de publication : 2008 Article en page(s) : pp. 541–546 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Fine-grained soil Model tests Barriers Clays Silts Groundwater pollution Résumé : In the present note, the susceptibility to necking of a subsurface barrier installed by the vibrating beam method in fine-grained soils is investigated by physical model tests. Two soils are investigated, a clayey soil and a silty soil. The model soil is prepared by moist tamping. The recipe of slurry in the model tests is widely used in the foundation engineering industry. The dynamic loading exerted by the vibration of the adjacent panel is simulated by a shake table. The test results show that soil plasticity and water content are the major influence factors on the susceptibility to necking. The plasticity index can be used as an indicator for the susceptibility to necking of subsurface barrier installed by the vibrating beam method in fine-grained soils. Other influence factors on necking are also investigated and their implications for practice are discussed. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2854 [...] [article] Model tests on discontinuities in subsurface barrier installed by the vibrating beam method [texte imprimé] / W. Wu, Auteur ; F. Aschauer, Auteur ; G. Reiser, Auteur . - 2008 . - pp. 541–546.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 541–546
Mots-clés : Fine-grained soil Model tests Barriers Clays Silts Groundwater pollution Résumé : In the present note, the susceptibility to necking of a subsurface barrier installed by the vibrating beam method in fine-grained soils is investigated by physical model tests. Two soils are investigated, a clayey soil and a silty soil. The model soil is prepared by moist tamping. The recipe of slurry in the model tests is widely used in the foundation engineering industry. The dynamic loading exerted by the vibration of the adjacent panel is simulated by a shake table. The test results show that soil plasticity and water content are the major influence factors on the susceptibility to necking. The plasticity index can be used as an indicator for the susceptibility to necking of subsurface barrier installed by the vibrating beam method in fine-grained soils. Other influence factors on necking are also investigated and their implications for practice are discussed. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2854 [...]
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 547–550
Titre : Laboratory analysis of carbon dioxide hydrate-bearing sands Type de document : texte imprimé Auteurs : Lingyun Wu, Auteur ; Jocelyn L. Grozic, Auteur Année de publication : 2008 Article en page(s) : pp. 547–550 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Natural gas Soil gas Triaxial tests Sand Carbon dioxide Methane Laboratory tests Résumé : Gas hydrates are ice-like compounds composed of water molecules that encapsulate natural gas molecules in a very compact form. Three groups of CO2 hydrate-bearing sand specimens were formed using a specialized triaxial test apparatus at different temperature and different pressure to examine the physical effects, such as stress and deformation changes, of hydrate dissociation on the surrounding soil. The triaxial test data indicate: (1) the higher the pressure, the higher hydrate content; (2) the lower the temperature, the higher hydrate content; (3) the greater the amount of gas hydrate initially present in the specimen, the greater the reduction of effective stress upon dissociation and the lower strength; and (4) dissociation of even a small percentage of gas hydrates will cause a dramatic reduction in the soil strength and could lead to failure. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2854 [...] [article] Laboratory analysis of carbon dioxide hydrate-bearing sands [texte imprimé] / Lingyun Wu, Auteur ; Jocelyn L. Grozic, Auteur . - 2008 . - pp. 547–550.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°4 (Avril 2008) . - pp. 547–550
Mots-clés : Natural gas Soil gas Triaxial tests Sand Carbon dioxide Methane Laboratory tests Résumé : Gas hydrates are ice-like compounds composed of water molecules that encapsulate natural gas molecules in a very compact form. Three groups of CO2 hydrate-bearing sand specimens were formed using a specialized triaxial test apparatus at different temperature and different pressure to examine the physical effects, such as stress and deformation changes, of hydrate dissociation on the surrounding soil. The triaxial test data indicate: (1) the higher the pressure, the higher hydrate content; (2) the lower the temperature, the higher hydrate content; (3) the greater the amount of gas hydrate initially present in the specimen, the greater the reduction of effective stress upon dissociation and the lower strength; and (4) dissociation of even a small percentage of gas hydrates will cause a dramatic reduction in the soil strength and could lead to failure. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A4%2854 [...]
Exemplaires
| Code-barres | Cote | Support | Localisation | Section | Disponibilité |
|---|---|---|---|---|---|
| aucun exemplaire | |||||
