The aim of this article is to present the slope stability charts for two layered soil slopes by using the strength reduction method (SRM). The primary focus is to provide a quantitative estimation of the improvement of slope stability when a stronger layer is placed over the weaker layer. The SRM carried in this work comprises a series of finite element lower bound (LB) and upper bound (UB) limit analysis in conjunction with nonlinear optimization. Unlike the limit equilibrium method (LEM), there is no need to consider any prior assumptions regarding the failure surface in SRM. The study is carried out for different combinations of (i) slope angles (β), (ii) strength properties of the top and the bottom layer (c, ϕ) and (iii) different thickness of the top layer. The failure patterns are shown for a few cases.

本文的目的是通过强度折减法（SRM）呈现两层土坡的边坡稳定性图。主要关注点是在较弱的层上放置较强的层时，提供对边坡稳定性改善的定量估计。在这项工作中进行的 SRM 包括一系列结合非线性优化的有限元下界 (LB) 和上限 (UB) 极限分析。与极限平衡法 (LEM) 不同，在 SRM 中无需考虑任何关于失效表面的先验假设。研究是针对 (i) 倾斜角 ( β )、(ii) 顶层和底层的强度特性 ( c , ϕ ) 的不同组合进行的) 和 (iii) 不同厚度的顶层。显示了几种情况的故障模式。