A multi-level failure surface localization method for anti-dip rock slope based on improved AOS

Abstract

The geometry of the failure surface of anti-dip bedding rock slopes (ABRSs) is often not a regular arc or folded line. Progressive failure with multi-level failure surface is observed in the failure process of ABRSs. This study proposes a stability assessment method for ABRSs that considers the multi-level failure surface to address this challenge. The proposed new approach considers the formation of multi-level failure surfaces within the deformation and failure process of ABRSs. It utilizes an Atomic Orbital Search (AOS) optimization algorithm based on the Tent chaotic mapping strategy to locate the multiple failure surfaces of ABRSs. Centrifuge tests were employed to verify the validity of the proposed method. The research results indicate that the proposed strategy improves the convergence speed of the AOS, in comparison to the standard algorithm, while also avoiding the problem of getting stuck in local optima; the multi-level failure surfaces of the ABRS located by the proposed method are consistent with the results of the centrifuge tests, achieving a high degree of prediction accuracy; the rock mechanics parameters of internal friction angle of joints and tensile strength of the rock layer significantly affect the critical failure surface position of ABRSs.