软黏土地基流固耦合非线性力学行为的有限元数值分析

FEM analysis of nonlinear mechanical behavior of fluid-solid coupling for soft clay foundation

软黏土存在黏滞和固结作用的时效性,同时还存在水分作用的耦合效应。为研究水分含量对软黏土地基效应的影响,根据多孔介质理论结合罚参数法和Galerkin加权残值法,在多孔介质中引入了弹黏塑性力学效应,推导了软黏土地基的固液两相多孔介质模型和控制场方程,建立了有限元计算模型,给出了求解算法并编制了有限元程序。算例对比分析表明,该程序能够有效模拟软黏性土地基的力学响应。

Soft clay is influenced by the time-dependence of viscosity and consolidation as well as coupling effect of moisture. In order to study the effect of moisture content on soft clay foundation, by introducing the elastic-viscoplastic mechanics effects into porous media, the model for solid-liquid two-phase porous media and the governing equations for soft clay foundation are deduced, and the finite element model and program are established based on the theory of porous media, the penalty function parameter method and the Galerkin weighted residual method. Compared with the theoretical results and the observed data, it is indicated that the proposed model and procedure are suitable for simulating the mechanical behaviors of soft clay foundation.