Multi-slip surfaces extraction method for slopes based on energy dissipation rate index

Accurate identification of multi-slip surfaces in complex slope failure modes is essential for risk assessment and reinforcement design. In this study, a multi-slip surfaces extraction method based on energy dissipation rate (EDR) index is proposed. Firstly, the elasto-viscoplastic damage model is employed to simulate slope failure procedure. Then, a ridge-finding technique is applied to the EDR field to generate a feature point set, which is subsequently denoised through convex hull check and statistical threshold. Additionally, density-based spatial clustering of applications with noise (DBSCAN) is adopted for the initial clustering of feature points, followed by multi-model fitting via random sample consensus (RANSAC). The proposed method is validated based on a homogeneous slope and an undrained clay slope with a thin weak layer. Moreover, it is applied to a practical reservoir bank slope to analyze the spatial distribution of multi-slip surfaces and stability evolution during impoundment. The results indicate that, under complex stress conditions, EDR offers distinct advantages over traditional indices such as displacement and shear strain increment. The analyzed reservoir bank slope exhibits a potential risk of overall instability along the inherent surface of rupture, alongside several local instability modes. The developed approach provides a novel strategy for automated identification of multi-slip surfaces, significantly reducing manual intervention.