Abstract:Ideal elastoplastic model used in deformation analysis induced by underground engineering excavation leads to inaccurate prediction. Based on modified hardening soil model,considering the effect of small strain condition on soil behavior,a case study of deep excavation on the deformation of diaphragm wall and settlement of ground surface is numerical analyzed. The results show:according to the movement of diaphragm wall,the prediction result by using ideal elastoplastic mode—Mohr-Coulomb(MC) model is larger than observed deformation,and especially the part below the base of excavation. The result obtained from hardening soil model is consistent with but a little larger than the observed deformation. For the prediction of surface settlement,the trough obtained from MC model is deeper and wider than that obtained from modified hardening soil model,and the settlement from hardening soil model is larger. In general,because modified hardening model can be used to simulate the variation of soil behavior such as modulus and small strain during different loading and unloading states,modified hardening model is superior to MC model and hardening soil model whether in value and regular of deformation prediction.
崔 溦,王 宁,宋慧芳. 基于修正硬化模型的软土深基坑变形数值分析[J]. 岩石力学与工程学报, 2013, 32(s2): 4041-4047.
CUI Wei,WANG Ning,SONG Huifang. DEFORMATION NUMERICAL ANALYSIS OF DEEP EXCAVATION IN SOFT SOIL BASED ON MODIFIED HARDENING MODEL. , 2013, 32(s2): 4041-4047.
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