Experimental study on interaction between rock granular flow and different structural forms of rigid retaining walls

Rock granular flow is a kind of rock debris aggregate produced by landslides, which can be greatly destructive due to its high velocity, long distance and large impact force. In this paper, dynamic responses and energy dissipation capacities of different shapes rigid retaining walls (rectangle, angular, arc-shaped) under the impact of rock granular flow were investigated. The experiments primarily focused on the influences of granular flow mass and slope angle on motion characteristics of rock granular flow and impact force of retaining wall. In addition, the relationship between the energy dissipation capacity and the structural form of the retaining wall were explored through quantitative analysis peak acceleration of different shapes retaining wall. According to the experimental results, substantial increases both in the impact velocity of rock granular flow and in the maximum resultant of impact force of retaining wall with increasing rock granular flow mass and slope angle were observed under the coupling effects of the granular flow mass and slope angle. Moreover, the impact force at different height of the rectangle retaining wall varied evidently with slope angle, but was mainly concentrated in the lower half of the retaining wall. In addition, the energy dissipation capacity of arc-shaped retaining wall was the best among those rigid retaining walls. This study can contribute to a better understanding of the flow-structure interaction and provide guidelines for the engineering application of the new retaining wall.