Three-dimensional slope stability analysis method based on perturbation displacement isosurface

Three-dimensional (3D) slope stability analysis is a difficult point in the field of slope stability analysis in geotechnical engineering, and using 3D methods for slope stability analysis is of theoretical and practical significance. First, finite difference method was used to establish a numerical model of the slope, and then a tiny disturbance was applied to the balanced slope. The displacement isosurface generated after the disturbance was regarded as the potential sliding surface. Finally, the stability safety factor of multiple potential sliding surfaces was calculated, with the minimum value as the slope safety factor, and the corresponding sliding surface as the critical sliding surface. Results showed that the 3D slope stability analysis method based on the perturbation equivalence surface could accurately and efficiently obtain the most dangerous sliding surface and safety factor. It was reasonable and straightforward. It exhibited strong logic and clear physical meaning. The critical sliding surface obtained was also consistent with the actual project. This research could provide new ideas for calculating 3D slope stability in geotechnical engineering.