- Email: [email protected]
Analysis of incremental excavation based on critical state theory
50A 911391 FEM analysis for the expansive soil with directional joints Li, N Proc International Conference on Engineering Problems of Regional Soils, Baiting, 11-15 August 1988 P602-605. Publ Beijing: International Academic Publishers, 1989 A swelling softening soil model, which takes into account stress state and water content, and a viscoelastic model are presented for expansive soils. They are applied within finite element analysis to examine slope stability of a jointed soil mass. Cohesion and friction angle, which are affected by water content, and joint geometry influence slope stability. Creep properties affect sliding time. Slope failure may result from the sequence rainfall, wetting, swelling, softening, failure initiation, accelerating creep sliding.
911392 Dynamic soil properties of weathered pumice on Mt. Ontake in Japan Yasuda, S; Momikura, Y; Kochoh, T Proc lnternutional Conference on Engineering Problems of Regional Soils, Beijing, 11-15 August 1988 P753- 758. Publ Beijing: International Academic Publishers, 1989 Four very large slides were caused by the Naganoken-seibu earthquake in 1984. Weathered pumice was found on the slip surface of 3 slides and volcanic sand at the other. Geology and topography of the sites were examined and dynamic shear strength of the soils investigated in the laboratory. Results were used in slope stability analysis. The strength of the pumice had been decreased by long term weathering, and safety factors reduced to less than I. Erosion at the slope toe also affected stability in one case.
911393 Roles of fadngs in reinforcing steep clay slopes with a nonwoven geotextile Nakamura, K; Tamura, Y; Tatsuoka, F; Iwasaki, K; Yamauchi, H Proc International Geotcchnical Symposium on Theory and Practice of Earth Reinforcement, Fukuoku Kyuslm, 5-7 October 1988 P553-558. Publ Rotterdam: A A Balkema, 1988 Full scale embankments of cohesive soils reinforced with geotextile layers of different lengths and with facings of different flexibility (geotextile, shotcrete, concrete panels) were constructed. Post construction settlement and displacement are described. The embankments were subjected to natural and artificial rainfall tests and simulated earthquake loading. Influence of reinforcement length and rigidity of facing on failure mechanisms and stability is discussed.
Earth retaining structures 911394 Elasto-plastic consolidation analysis for strutted excavation in clay Yong, K Y; Lee, F H; Parnpioy, U; Lee, S L Comlmt Geoteeh V8, N4, 1989, P311-328 Field data from an instrumented project on the time dependent behaviour of an excavation support system are compared to results of undrained and consolidation analyses. Pore pressure dissipation is modelled using a fully coupled consolidation analysis. The soil is assumed an elastic-perfectly plastic,
Mohr Coulomb material. Undrained analysis underestimates wall movement and fails to reflect its progressive nature, but these are well predicted by the consolidation analysis. Sequential excavation can also be modelled by the consolidation analysis.
911395 Analysis of incremental excavation based on critical state theory Borja, R I J Geotech Engng Di~ ASCE VII6, N6, June 1990, P964-985 Problems associated with accurate modelling of incremental excavation are addressed using an efficient finite element based analysis algorithm that satisfies the uniqueness principle for cutting an elastic medium and a new, stable stress point integration algorithm for the Cam clay model. The procedure is unconditionally convergent at subfailure condition. Plane strain, axisymmetric, and three dimensional cases, and drained and undrained loading are considered. Practical application to a braced wall movement prediction in soft soil is illustrated.
911396 Design of a foundation wall placed in an elastically creeping bed Kakosimidi, N F Soil Meek Found Engng V26, NS, Sept-Oct 1989, P218-222 Bending moments and reactive forces for a wall embedded in a creeping soil mass are evaluated. The problem is reduced to the single general problem of binding of strips within an elastically creeping bed. This removes the complications introduced by inclusion of break of bed continuity, for which compensating factors are suggested.
911397 FEM analysis of polymer grid reinforced-soil retaining walls and its application to the design method Ogisako, E; Ochiai, H; Hayashi, S; Sakai, A Proc lntermuionM Geotecluu'cal Symposiiml on Theory and Practice of Earth Reinforcement, Fukuoka Kyuslm, 5-7 October 1988 1'559-564. Publ Rotterdam: A A Balkema, 1988 Finite element analysis of reinforced earth retaining walls is presented which takes into account the dependence of the pullout resistance of the polymer grid on its displacement. Distribution of earth pressure and its relation to number, spacing and length of reinforcing elements are analysed. A design chart for checking wall displacements is shown.
911398 Theory and practice of 'Reinforcing' steep slopes with nonwoven geotextiles Resl, S; Schneider, H; Werner, G Proc lntematimud Geoteelmical Symposium on Theory and Practice of Earth Reimforce~nt, Fukmoka Kyzclm, 5-7 October 1988 P565-570. Publ Rotterdam." A A Balkema, 1988 A design for reinforced earth retaining walls is presented, which combines horizontal reinforcement and soil filled bags, formed by turning over the textile, as the face. Analysis suggests a stable wall can be built with a lower tensile strength textile than for conventional designs. Improvement of fill shear strength by compaction, drainage by the geotextile, and long term in-soil stress strain characteristics of the textiles are examined. Some practical examples of structures using needle punched nonwoven geotextiles are presented.
© 1991 Pergamon Press pie. Reproduction not permitted
911392 Dynamic soil properties of weathered pumice on Mt. Ontake in Japan Yasuda, S; Momikura, Y; Kochoh, T Proc lnternutional Conference on Engineering Problems of Regional Soils, Beijing, 11-15 August 1988 P753- 758. Publ Beijing: International Academic Publishers, 1989 Four very large slides were caused by the Naganoken-seibu earthquake in 1984. Weathered pumice was found on the slip surface of 3 slides and volcanic sand at the other. Geology and topography of the sites were examined and dynamic shear strength of the soils investigated in the laboratory. Results were used in slope stability analysis. The strength of the pumice had been decreased by long term weathering, and safety factors reduced to less than I. Erosion at the slope toe also affected stability in one case.
911393 Roles of fadngs in reinforcing steep clay slopes with a nonwoven geotextile Nakamura, K; Tamura, Y; Tatsuoka, F; Iwasaki, K; Yamauchi, H Proc International Geotcchnical Symposium on Theory and Practice of Earth Reinforcement, Fukuoku Kyuslm, 5-7 October 1988 P553-558. Publ Rotterdam: A A Balkema, 1988 Full scale embankments of cohesive soils reinforced with geotextile layers of different lengths and with facings of different flexibility (geotextile, shotcrete, concrete panels) were constructed. Post construction settlement and displacement are described. The embankments were subjected to natural and artificial rainfall tests and simulated earthquake loading. Influence of reinforcement length and rigidity of facing on failure mechanisms and stability is discussed.
Earth retaining structures 911394 Elasto-plastic consolidation analysis for strutted excavation in clay Yong, K Y; Lee, F H; Parnpioy, U; Lee, S L Comlmt Geoteeh V8, N4, 1989, P311-328 Field data from an instrumented project on the time dependent behaviour of an excavation support system are compared to results of undrained and consolidation analyses. Pore pressure dissipation is modelled using a fully coupled consolidation analysis. The soil is assumed an elastic-perfectly plastic,
Mohr Coulomb material. Undrained analysis underestimates wall movement and fails to reflect its progressive nature, but these are well predicted by the consolidation analysis. Sequential excavation can also be modelled by the consolidation analysis.
911395 Analysis of incremental excavation based on critical state theory Borja, R I J Geotech Engng Di~ ASCE VII6, N6, June 1990, P964-985 Problems associated with accurate modelling of incremental excavation are addressed using an efficient finite element based analysis algorithm that satisfies the uniqueness principle for cutting an elastic medium and a new, stable stress point integration algorithm for the Cam clay model. The procedure is unconditionally convergent at subfailure condition. Plane strain, axisymmetric, and three dimensional cases, and drained and undrained loading are considered. Practical application to a braced wall movement prediction in soft soil is illustrated.
911396 Design of a foundation wall placed in an elastically creeping bed Kakosimidi, N F Soil Meek Found Engng V26, NS, Sept-Oct 1989, P218-222 Bending moments and reactive forces for a wall embedded in a creeping soil mass are evaluated. The problem is reduced to the single general problem of binding of strips within an elastically creeping bed. This removes the complications introduced by inclusion of break of bed continuity, for which compensating factors are suggested.
911397 FEM analysis of polymer grid reinforced-soil retaining walls and its application to the design method Ogisako, E; Ochiai, H; Hayashi, S; Sakai, A Proc lntermuionM Geotecluu'cal Symposiiml on Theory and Practice of Earth Reinforcement, Fukuoka Kyuslm, 5-7 October 1988 1'559-564. Publ Rotterdam: A A Balkema, 1988 Finite element analysis of reinforced earth retaining walls is presented which takes into account the dependence of the pullout resistance of the polymer grid on its displacement. Distribution of earth pressure and its relation to number, spacing and length of reinforcing elements are analysed. A design chart for checking wall displacements is shown.
911398 Theory and practice of 'Reinforcing' steep slopes with nonwoven geotextiles Resl, S; Schneider, H; Werner, G Proc lntematimud Geoteelmical Symposium on Theory and Practice of Earth Reimforce~nt, Fukmoka Kyzclm, 5-7 October 1988 P565-570. Publ Rotterdam." A A Balkema, 1988 A design for reinforced earth retaining walls is presented, which combines horizontal reinforcement and soil filled bags, formed by turning over the textile, as the face. Analysis suggests a stable wall can be built with a lower tensile strength textile than for conventional designs. Improvement of fill shear strength by compaction, drainage by the geotextile, and long term in-soil stress strain characteristics of the textiles are examined. Some practical examples of structures using needle punched nonwoven geotextiles are presented.
© 1991 Pergamon Press pie. Reproduction not permitted