Hazard Zonation and Risk Assessment of a Debris Flow under Different Rainfall Condition in Wudu District, Gansu Province, Northwest China

Debris flows induced by heavy rainfall are a major threat in Northwest and Southwest China, due to its abrupt occurrence long runout. In light of this, this work presents the runout simulation risk assessment Boshuigou debris flow under different conditions Wudu district, Gansu Province, China. Based on field reconnaissance, geomorphological feature main source were described. With application FLO-2D simulation, potential depth extent 100-year return-period 50-year calculated. The maximum velocities 5.46 5.18 m/s, respectively. Accordingly, depths 5.85 5.57 m. Then, hazard zonation was conducted combination construction other properties within impact zone, finally completed. This method for considering solid water flow, which can provide basic reference mitigation reduction geohazards torrential rainfall.