基于广义剪应变的各向异性固结饱和砂土超静孔压发展模型  

Generalized shear strain-based model for development of excess pore water pressure in saturated sand under anisotropic consolidation

作　　者：赵福堂 吴祁新 郑俊杰 郑烨炜 ZHAO Futang;WU Qixin;ZHENG Junjie;ZHENG Yewei(School of Civil Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学土木建筑工程学院,湖北武汉430072

出　　处：《岩土工程学报》2025年第2期315-323,共9页Chinese Journal of Geotechnical Engineering

基　　金：国家重点研发计划项目(2022YFC3080400);国家自然科学基金项目(52208366;52078392)。

摘　　要：各向异性固结条件下饱和砂土中超静孔隙水压力的发展规律对于理解砂土液化行为至关重要。使用空心圆柱扭剪仪进行了一系列扭剪试验,研究了初始固结条件(初始平均有效应力p'0、固结应力比K)和循环加载条件(循环应力比CSR)对饱和砂土的广义剪应变γ_(g)和超静孔压比r_(u)发展规律的影响。试验结果表明,各向异性固结条件下的砂土表现出三类破坏模式:循环迁移、循环液化和残余累积变形。在所有3种破坏模式下,归一化超静孔压比r_(u,n)都与γ_(g)相关。据此提出了考虑各向异性固结条件的饱和砂土超静孔隙水压力预测模型。该模型能合理预测不同固结应力状态下超孔隙水压力的发展。The development pattern of the excess pore water pressure in saturated sand under anisotropic consolidation conditions is crucial for understanding the liquefaction behavior of sand.In this study,a series of torsional shear tests are conducted using the hollow-cylinder torsional apparatus to examine the influences of the initial consolidation conditions(initial mean effective stress p'0 and consolidation stress ratio K)and cyclic loading conditions(cyclic stress ratio,CSR)on the development patterns of the generalized shear strain(γ_(g))and excess pore water pressure ratio(r_(u))in saturated sand.The experimental results indicate that the sands under anisotropic consolidation exhibit three failure modes:cyclic mobility,cyclic liquefaction and residual cumulative deformation.The normalized ru can be correlated withγ_(g) for all the three failure modes.A prediction model for the excess pore pressure is proposed considering the anisotropic consolidation conditions for saturated sand.The model can reasonably predict the development of pore water pressure under different consolidation stress states.

关 键 词：饱和砂土 各向异性固结 液化 超静孔压 广义剪应变 

分 类 号：TU435[建筑科学—岩土工程]