Dynamic process of rock avalanche and dynamic interaction between rock avalanche and hazard-bearing bodies

To simulate the dynamic behavior of rock avalanche against hazard-bearing bodies, an indoor small-scale physical model test apparatus was established, and then, the influence of retaining wall height on the velocity and accumulation form of rock avalanche was analyzed. The analysis of the deformation and failure of retaining wall due to rock avalanche impact was carried out by means of coupled PFC 3D -FLAC 3D theory. The results indicate that the volume of avalanche accumulated in the upper part of retaining wall increases with the retaining wall height, while the accumulation width at the lower part of retaining wall, the movement distance of rock avalanche, and the accumulation length all decrease with retaining wall height. The accumulation forms are similar under various heights of retaining wall. The forces of rock avalanche acting on the wall structure include a drag force ( F d ), a passive earth pressure ( F p ), and a gravitational and frictional force ( F gf ). When the impact force approaches its peak, F d , F p , and F gf account for 75 ~ 91%, 1 ~ 2%, and 7 ~ 23%, respectively. The impact force against the retaining wall, the deformation position, and the magnitude of the retaining wall vary with time.