High-speed long-runout landslide scraping and entrainment effects: A case study on Shuicheng landslide.

Erosion and entrainment significantly increase the volume and destructive potential of high-speed long-runout landslides. Previous studies seldom quantitatively address these effects, and even fewer incorporate the extent of slope weathering into the analysis of landslide dynamics. This study addressed this gap by developing a framework for dynamic analysis, combining Finite Element Method-Smoothed Particle Hydrodynamics-Finite Discrete Element Method (FEM-SPH-FDEM), and applying it to the Shuicheng landslide. Simulation results closely matched field data, revealing substantial sliding mass deviation and velocity variations influenced by rocky ridges and valleys. According to the simulation, the weathering degree of rock slope significantly affects landslide dynamic processes. The interparticle friction coefficient is crucial for accurately modeling these processes using the SPH-FDEM method. Additionally, by incorporating landslide erosion behavior into the framework, the case study indicates that the volume of landslides in Shuicheng County increased by approximately 0.6 times. Three stages of evolution mechanisms of high-altitude landslide-induced erosion behavior are proposed in this paper, highlighting the effectiveness of this framework in understanding landslide mechanisms and providing information for prevention strategies in high-altitude, highly weathered areas. • FEM-SPH-FDEM accurately capture landslide scraping and entrainment effects. • Rock slope weathering considerably enhances scraping and entrainment effects. • Significant landslide volume increase by scraping and entrainment is quantified. • Terrain and friction coefficients underscore the need for landslide modeling. [ABSTRACT FROM AUTHOR]