Development of a Generalized Slip Surface Generation Model and Stress Calculation Method for Limit-Equilibrium Analysis of Slopes

Abstract

This study introduces a generalized slip surface (GSS) based on the Mohr–Coulomb strength criterion, which encompasses various types of slip surfaces. It also presents a novel approach for multisegment GSSs in layered slopes. To improve stability calculations, a stress calculation mode on the slip surface was integrated within the limit-equilibrium (LE) theoretical framework. This involved creating a rational function for the normal stress on the slip surface, derived using Taylor series expansion and the composition of the normal stress. The study also incorporated stress constraint conditions at both ends of the slip surface to consider the tension- and compression-shear failure characteristics of the slope. A formula for conducting LE analysis of slope stability was derived, ensuring all mechanical equilibrium conditions for the sliding body. By comparing and analyzing several slope examples, the feasibility of the present method was successfully demonstrated. Additionally, stability charts and a recognition diagram for failure mode in a homogeneous slope were generated to provide valuable insights. Furthermore, the engineering applicability of the single circular slip surface model in the LE analysis of stability for a horizontally layered slope was comprehensively evaluated based on the developed GSS.