Influence of topography on the impact mechanism of dry granular flow: A DEM study

A detailed investigation on the influence of topography on the impact mechanism of dry granular flow is still lacking. In this study, the effect of topography was examined quantitatively through a non-dimensional number called terrain index using discrete element method simulations after the numerical model was calibrated based on a physical experiment. The results showed that the impact of granular flow on a barrier can be categorized into slope pileup impact, continuous impact, and mixed impact models. The growth, transition, reduction, and stability phases can be identified accurately based on the impact force curve on the barrier, whereas the transitional phase only exists when the terrain index is >1. A logarithmic expression can be used to determine the relationships between the normalized pileup height, accumulation length, maximum and final impact forces, and terrain index. These considerations can serve as a guide for the design of granular flow barriers.