有限元强度折减法进行土坡稳定分析的精度研究

Study on Accuracy of Soil Slope Stability Analysis Based on Strength Reduction FEM

有限元强度折减法分析土坡稳定性的结果受到有限元单元类型、网格密度和土坡边界范围的影响。为了得到上述因素合理的确定方法以提高计算精度,借助ABAQUS结合强度折减法进行了分析,结果表明采用二阶四边形单元,对土坡滑动区域的边界进行网格加密可以获得很好的精度,土坡边界范围建议取稍大于坡体破坏区即可,同时评价了三种失稳判据的优劣。

The soil slope stability analysis based on strength reduction FEM is influenced by finite element type, mesh density and slope boundary. In order to acquire the reasonable method for determining the above factors which could im- prove the calculation accuracy, ABAQUS combined with strength reduction method is adopted to make the analyses. The results show that better accuracy could be got when the second-order quadrilateral element is chosen and the meshes in the boundary of slope sliding region are refined, it is suggested that only slope boundary would be a little wider than slope failure area, and the pros and cons of three instability criteria are also evaluated.