Abstract: With the continuous advancement of highway construction in mountainous regions in China, the stability and disaster-causing mechanisms of waste dump sites have become one of the important factors in project construction evaluation. To achieve a comprehensive analysis of the stability and dynamic processes of instability disasters at waste dump sites, this paper introduces the strength reduction method (SRM) based on the material point method (MPM) in CoSim, a GPU-oriented parallel high-performance computing software. To verify the rationality of the algorithm, the MPM-SRM is compared with the limit equilibrium method (LEM) for a typical uniform slope. The results show that the two methods exhibit good consistency in both the factor of safety F_s and the potential sliding surfaces. Based on this, a case study of a highway waste dump site in Yunnan Province where rainfall-induced instability occurred is analyzed under both natural and heavy rainfall conditions. The results indicate that the slope of the waste dump site is stable under natural conditions, but becomes unstable and experiences large sliding deformation during heavy rainfall. The numerical simulation results correspond well with field investigation findings, demonstrating that the method proposed in this paper has significant advantages in stability analysis and dynamic analysis under large deformation of waste dump site slopes. It can simulate the entire process of slope behavior, from stability to large deformation, flow, and deposition.

Key words: material point method (MPM), strength reduction method (SRM), stability analysis, factor of stability, waste dumpsite