Modelling the impact of particle flow on rigid structures: Experimental and numerical investigations

Abstract

Gravity-driven debris flow of granular particles down an inclined slope is a problem of growing concern in mountainous regions and poses a significant risk to people, roads, and other infrastructure. Different aspects of the problem have been previously investigated using physical modeling and numerical analysis. However, three dimensional pressure distribution on a barrier wall resulting from debris flow over a rough slope is scarce in the literature. In this study, a series of experiments have been conducted to track the movement of granular particles down a slope and measure the impact pressure imposed by the flowing particles on a nearby vertical wall. The particles are released from a container located at the top of the slope and the velocity profiles are recorded using marked pebbles and a high speed camera. The roles of the debris volume, slope angle and distance to the wall on the velocity profiles and impact forces are investigated. Validated using the experimental results, discrete element simulations are performed using PFC^3D to evaluate the effect of particle sizes on the flow characteristics and final impact pressure on the structure. Analysis showed that impact energy is highly affected by the slope inclination, particle velocity and runout distance.