Discrete Kinematic Mechanism for Nonhomogeneous Slopes and Its Application

Abstract

In the framework of limit analysis, most previous studies of nonhomogeneous slopes have only involved the spatial variation of cohesion, whereas cases involving the spatially varying friction angle have rarely been studied. The main aim of the study presented in this paper was to propose an effective approach for analyzing slopes with friction angle spatial variability. According to the upper-bound theorem of limit analysis, a new two-dimensional (2D) failure mechanism using a spatial discretization technique was studied. With this mechanism, the slip surface was composed of a series of straight lines, instead of the continuous curve used in conventional limit analysis. The mechanism-generation procedure for the slip surface is described herein, and the mathematical formulations for the weight work rate and energy dissipation are also presented. After a discussion about accuracy and efficiency, the validation of the proposed approach, conducted previous achievements and numerical simulations, is presented. The good agreement shows that the proposed mechanism is effective. Finally, the analysis of the stability of nonhomogeneous slopes, with friction angles varying linearly with depth, and the investigation into the effects of the slope angles and friction angle distributions are presented.