Effects of particle breakage on rockslide deposition formations: insights from rigid finite element modelling

This paper aims to investigate the influence of particle breakage on the dynamics and deposition of rockslides. A rigid-body finite element formulation incorporating bond beam element is proposed to model rock breakage behaviors. This approach enables simulations of particle fragment rolling, collisions between adjacent pieces, and impacts of pieces with the bedrock. Numerical analyses were conducted considering the variations in volumes, breakage modes, breakage efficiency, and the friction coefficient of bedrock surfaces. Simulation results demonstrate a negative linear correlation between the runout distance and the volume of rock blocks. Incorporating fragmentation effects, this study reveals that the breakage efficiency of maternal rock blocks significantly influences the energy dissipation process and the downslope movement of rockslides. Despite variations in breakage modes leading to distinct deposit configurations, run-out distances remain basically consistent. Analysis of block contributions from various source locations indicates that the longitudinal spreading of the deposit primarily depends on blocks distributed on the periphery of the rock mass.