基于无网格法的周期性波浪荷载作用下饱和土体动力响应分析

Dynamic response of saturated porous elastic soil under cyclic loading by using element-free Galerkin method

基于饱和土体Biot理论,采用无网格单元法分析了周期性波浪荷载作用下的饱和土体动力响应。根据移动最小二乘法,将饱和土体的位移、孔隙水压力进行移动最小二乘法离散,位移边界采用拉格朗日乘子法,将位移约束条件引入得到控制方程组。研究表明,无网格法的节点规则与不规则分布都可得到问题解,但相对而言,规则节点分布可以提高计算精度,不规则节点分布的计算结果也能够达到合理的计算精度。相对于有限元法,采用相同时间步长积分,无网格法能够避免计算结果的振动性。

Based on the Biot＇ s theory and the meshless element-free Galerkin method, the transient response of saturated porous elastic soil under wave-induced loading is presented. In this procedure, displacement and excess pore water pressure are approximated using the same shape functions constructed by moving least-square approximants. Lagrange multipliers are employed to implement essential and periodic boundary conditions. The current procedure performs very well not only for regular node distributions but also for irregular node distributions. ceptable. The numerical results are for the same time step size. Irregular node distribution has lower accuracy but the accuracy is ac- oscillation-free, while FEM has difficulty to get oscillation-free results