网格自适应有限元极限分析在边坡稳定分析中的应用

为规避有限元极限分析法应用于边坡计算中的奇异点问题，并进一步提高该算法的精度和效率，基于有限元极限分析理论，通过二次圆锥优化Mohr-Coulomb屈服准则，利用优化后的屈服准则衡量离散单元，依据预定应力、应变的阈值搜索出边坡塑性区离散单元，对塑性区网格单元标记并局部自适应，通过该过程的多次循环迭代，实现网格有目的局部自动加密，多次优化并最终找出合理的剪切带。实例计算结果表明，模型3次自适应后均能达到理想的精度和误差控制，验证了网格自适应方法的有效性。

Application of Mesh Adaption Finite Element Limit Analysis in Slope Stability Analysis

To avoid the singular point problem of the finite element analysis for the slope calculation and enhance the accuracy and effectiveness of this calculation method, based on finite element limit analysis, quadratic conic method is adopted to optimize Mohr-Coulomb yield criterion. And then the optimized yield criterion is used to evaluate the discrete unit, which is determined by the pre-set stress or strain threshold. The mesh element in plastic zone is marked and locally adapted. Local automatic mesh encryption is achieved and shear band is located after many times of loop iteration. Calculation results of an example prove that the model can achieve ideal accuracy and error control after three times of loop iteration. The effectiveness of the mesh adaptive method is verified.