As Wenchuan earthquake was of high magnitude and shallow seismic focus，it caused considerable damage and thousands of geo-hazards. Numerous geo-hazards broke out simultaneously and rock fall, rock avalanches, landslides, dammed lake and debris flows responded the earthquake violently. Most geo-hazards will produce large amounts of sediment into the river, such as the sediment due to the strong main shock and aftershock, the sediment generated by the excavation of landslide dam spillway and the debris flow caused by rainfall and flash flood, etc. Find out the sediment transport rules is important for the post-disaster reconstruction, debris flow disaster monitoring and warning, river regulation and flood control and resource utilization. According to the characteristics of the slope sediment incipient motion and it’s relevant research foundation, with the consideration of relative exposure degree, relative roughness, shape coefficients, sediment restart incipient motion of rock avalanche bodies and landslide bodies was studied, and we deduced sediment incipient motion conditions of rock avalanche bodies and landslide bodies after earthquake.
