土坡稳定极限分析上限法中的多解性分析

土坡稳定极限分析上限法中采用了完全塑性区假定,即假定土坡内存在一个处处位于屈服面上的滑动体。将滑动体内部条块界面上的强度发挥系数视为优化变量,利用功能平衡方程得到了对于给定滑动面的多个安全系数,基于和声算法和潘家铮极值原理选择其中最大的安全系数作为该滑动面的抗滑稳定安全系数,利用该方法对于两个典型土坡算例进行了分析,将其结果与常规极限分析上限法结果进行了比较,给出了完全塑性区假定对计算结果的影响。

Multiple solutions in upper bound limit analysis of soil slopes

The assumption of existence of total plastic zone is made in the upper bound limit analysis, i.e. there exists a sliding body satisfying yielding equation in slopes. However, the mobilized extent of inter-slice strength is taken as optimized variables in this paper; and multiple solutions can be obtained by using virtual work-energy equation. The solution which is the biggest among those multiple ones is used to assess the stability for given sliding body. Two soil slopes are analyzed using the proposed method; and the results are compared to those by general upper bound method. The effect of this assumption on the stability results is given.