Enhanced Shear Strength Reduction Method for Stability Analysis of High-Friction Slopes: Implementation, Verification, and Application

Abstract

Over the last two decades, the shear strength reduction method (SRM) has emerged as a prominent alternative for slope stability analysis. However, existing studies reveal significant differences (16%–28%) between the factor of safety (FOS) achieved by the traditional SRM and the limit analysis method (LAM) for steep slopes with high friction. To address this limitation, this study proposes an enhanced shear strength reduction method (ESRM) that dynamically adjusts the dilation angle of geomaterials based on their stress states. Subsequently, the ESRM is comprehensively verified against the LAM analytical solution through extensive sensitivity analyses and a benchmark study, involving 201 sets of slope experimental groups with different geometric parameters and geomaterial parameters. The results show that the maximum error in the FOS achieved with the ESRM is only 8%, and the predicted distribution and development of the potential slip surface are also satisfactory, confirming the applicability of the ESRM for steep slopes with high friction. Simultaneously, considering that the LAM analytical solution cannot be used for engineering-level verification, the engineering-level comparison methods of the ESRM, namely, the Davis A approach and Davis B approach, are reproduced and verified within the same verification framework. Results demonstrate that only the Davis B approach achieves satisfactory accuracy. Finally, a case study of the ShaiKou landslide is conducted. The ESRM and Davis B approach achieve highly consistent FOS values of 1.259 and 1.258, respectively, along with comparable slip surface distribution and development, further evaluating the practical value of the ESRM in analyzing engineering problems involving with high-friction slopes.