强度折减法在土质边坡有限元分析中的应用

Application of Strength Reduction Method in FEM Analysis of Soil Slope

基于ANSYS的有限元分析程序,采用一系列的DP屈服准则求解安全系数的上下限值。通过土质边坡分析与传统极限平衡法相比,其分析结果显示,土质边坡均为不稳定。有限元分析方法利用平面应变摩尔-库仑匹配DP准则在求解平面应变问题时,精度较高,而且直接获得带状塑性区的位置和边坡滑移的方向。基于DP准则的有限元强度折减方法获得的安全系数的上下限值,更能为复杂边坡的分析提供参考依据。

Based on the finite element analysis program in ANSYS software, a series of DP yield criteria were applied to solve the upper and lower limits of safety factor. Through comparison between the results from the soil slope analysis and traditional limit equilibrium method, it was obtained that the soil slope is instable regardless of the method used. The finite element analysis used plane strain Mohr-Coulomb matching with DP criteria to get a high accuracy when solving plane strain related problems, and to acquire the location of strip plastic zone and the direction of slope sliding directly. Compared with traditional limit equilibrium method, the upper and lower limits of safety factor acquired by finite element strength reduction method based on DP criteria are more competent to provide reference to analysis of slope in more complex conditions.