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| NUMERICAL SIMULATION AND STABILITY DISCUSSION OF A REINFORCED SOIL RETAINING WALL ON SOFT SOIL FOUNDATION |
| CHEN Jianfeng，LIU Junxiu，SHI Zhenming |
| (Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China) |
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Abstract A two-dimensional numerical model was established for a reinforced soil retaining wall on soft soil foundation. The settlements，horizontal displacements，earth pressures of retaining wall and axial strains of geogrid were simulated under the condition of step loading. The computed results were found to basically agree with the measurements. The stability and location of slip surface of the reinforced soil retaining wall computed by the finite element strength reduction method coincide with the observed results，indicating a deep-seated failure. The maximum computed and measured strains of each geogrid layer appear at the position 4 to 6 m away from the wall，which is very different from the Rankine failure surface stated by current design theory for reinforced soil retaining walls. The reason is that the current design theory for reinforced soil retaining walls is based on the hypothesis of rigidity foundation and does not consider the effect of foundation deformation on the strain distributions and stability of reinforced soil retaining walls. The effect of lengthening the bottom reinforcements on the stability of the reinforced soil retaining wall was further analyzed using the numerical model. It is indicated that the lengthening values and reinforcement-lengthening numbers apparently affect the stability of the reinforced soil retaining wall on soft soil foundation. The obtained curves of factor of safety versus reinforcement- lengthening number for various lengthening values were considered to be significant for design of reinforced soil retaining walls on soft soil foundation.
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Received: 31 March 2012
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| [1] BATHURST R J，WALTERS D，VLACHOPOULOS N，et al. Full scale testing of geosynthetic reinforced walls[C]// Advances in Transportation and Geoenvironmental Systems Using Geosynthetics. [S.l.]：ASCE，2000：201–217.
[2] 章为民，赖忠中，徐光明. 加筋挡土墙离心模型试验研究[J]. 土木工程学报，2000，33(3)：84–91.(ZHANG Weimin，LAI Zhongzhong，XU Guangming. Centrifuge modeling of geotextile-reinforced cohesiveless soil retaining walls[J]. China Civil Engineering Journal，2000，33(3)：84–91.(in Chinese))
[3] ROWE R K，SKINNER G D. Numerical analysis of geosynthetic reinforced retaining wall constructed on a layered soil foundation[J]. Geotextiles and Geomembranes，2001，19(7)：387–412.
[4] WU J，LEE K，PHAM T. Allowable bearing pressures of bridge sills on GRS abutments with flexible facing[J]. Journal of Geotechnical and Geoenvironmental Engineering，2006，132(7)：830–841.
[5] ALFARO M C，HAYASHI S，MIURA N，et al. Deformation of reinforced soil wall/embankment system on soft clay foundation[J]. Soils and Foundations，1997，37(4)：33–46.
[6] SKINNER G D，ROWE R K. Design and behaviour of a geosynthetic reinforced retaining wall and bridge abutment on a yielding foundation[J]. Geotextiles and Geomembranes，2005，23(3)：234–260.
[7] TANCHAISAWAT T，BERGADO D T，VOOTTIPRUEX P. Numerical simulation and sensitivity analyses of full-scale test embankment with reinforced lightweight geomaterials on soft Bangkov clay[J]. Geotextiles and Geomembranes，2008，26(6)：498–511.
[8] 陈建峰，顾建伟，石振明，等. 软土地基加筋土挡墙现场试验研究[J]. 岩石力学与工程学报，2011，30(增1)：3 370–3 375.(CHEN Jianfeng，GU Jianwei，SHI Zhenming，et al. Field test study of reinforced soil wall on soft ground[J]. Chinese Journal of Rock Mechanics and Engineering，2011，30(Supp.1)：3 370–3 375.(in Chinese))
[9] BRINKGREVE R B J，BROERE W，WATERMAN D. Plaxis(Ver. 8) reference manual[R]. Delft：Plaxis BV，2004.
[10] SCHANZ T，VERMEER P A，BONNIER P G. Formulation and verification of the hardening-soil model[C]// Beyond 2000 in Compu- tational Geotechnics. Rotterdam：A. A. Balkema，1999：281–290.
[11] MICHALOWSKI R L. Coefficient of earth pressure at rest[J]. Journal of Geotechnical and Geoenvironmental Engineering，2005，131(11)：1 429–1 433.
[12] 中华人民共和国行业标准编写组. JTJ 021—89公路桥涵设计通用规范[S]. 北京：人民交通出版社，1989.(The Professional Standards Compilation Group of People?s Republic of China. JTJ 021—89 General code for design of highway bridges and culverts[S]. Beijing：China Communications Press，1989.(in Chinese))
[13] 中华人民共和国国家标准编写组. GB 50290—98 土工合成材料应用技术规范[S]. 北京：中国计划出版社，1998.(The National Standards Compilation Group of People?s Republic of China. GB 50290—98 Technical standard for applications of geosynthetics[S]. Beijing：China Planning Press，1998.(in Chinese))
[14] SKINNER G D，ROWE R K. A novel approach to estimating the bearing capacity stability of geosynthetic reinforced retaining walls constructed on yielding foundations[J]. Canadian Geotechnical Journal，2005，42(3)：763–779. |
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2012, Vol. 31 
