Experimental and numerical investigation on the propagation and impact behavior of dry granular flows.

The flow of granular materials such as soil, sand, and gravel is a common occurrence in mountainous area in the form of geological disasters, such as debris flows, landslides, and rock avalanches. A solid comprehension of the propagation and impact behavior of granular flow is imperative for the disaster prevention and mitigation. However, due to the intricacy of granular flow, it is difficult to predict the propagation and impact behavior of dry granular flows although some pioneering research works have been presented in the literature. In this paper, physical model experiments and numerical simulations based on the Particle Flow Code (PFC) are conducted to analyze the motion process, accumulation pattern and impact force of dry granular flow, and discuss the effects of slope angle, particle size and baffle height. Based on the high similarity between experimental and numerical results, it indicates that the run-out distance and peak velocity of the granular flow increases with the slope angle and particle size. Rigid baffle can significantly reduce the kinetic energy of the granular flow and decrease the run-out distance. The impact force of granular flow on the rigid baffle increases with the slope angle, particle size, and height of the baffle. The magnitude and distribution of the impact force on the baffle are in accordance with the contact force between the granular material and the baffle. These studies can contribute to better understand the characteristics of granular flow disasters and provide a reference for corresponding protection engineering. [ABSTRACT FROM AUTHOR]