Damming process and characteristics of landslide-debris avalanches

Landslide dam resulted from the natural blockages of river channels caused by rockslide-derived debris is easy to burst, which usually leads to a catastrophic damage. In this work, the physical model tests were carried out to investigate the movement process and accumulation characteristics of rock fragments on sliding surfaces with different characteristics, mainly taking into consideration of the influence of the initiated angle, sliding region angle and sliding bed roughness. The results show that after particle separation and collision during the movement process of rock fragments, large particles were widely distributed on the surface of the final deposit while small particles were deposited at the bottom. The sliding region angle and the roughness of the sliding surface had a great influence on the front inclination angle of the deposit dam. The sliding region angle also had a significant influence on the accumulation area and dam morphology in the rough group, while only a little effect was observed on the dam morphology in the smooth group. The distribution of the particles in the deposit dam was affected mainly by the roughness of the sliding surface. •The movement process and accumulation characteristics of rock fragments on sliding surfaces with different characteristics were investigated.•Large particles were widely distributed on the surface of the final deposit.•The sliding region angle and the roughness had a great influence on the front inclination angle.