Numerical Study about the Influence of the Basal Erosional and Block Effectson Dynamic Process of Debris Dlow

The mechanism of mass changes and block in debris transportation process is an important topic in the study of fast landslides, debris flows and avalanches. Basal erosion is recognized as a dynamic interaction between the original moving material and the entrained basal topsoil sheared along their non-slip contact surface.The dam is used to control mobility behavior of debris flows, to decrease the runout speed of debris flows, to reduce erosion capability and discharge, and tomake the flow direction diverge.In this paper, a new concept of yield rate has been proposed, and the erosional relationship between original moving material and the entrained basal topsoil has been analyzed. Apertinent mathematical model and numerical implementation have been formulated. Parametric numerical experiments have been conducted to compare the erosional effects. The influence of involved erosive material and block effects on the runout behavior and global mobility of moving material has been elucidated. The simulated results are consistent with available experimental and field observations. The excellent match to the field data suggests that it is a plausible potential application to analyze the gravity-driven flow with significant erosion. The defined dimensionless form and the proposed yield rate can be estimated conveniently in general geotechnical practices.