白龙江流域水峪沟泥石流危险性分析

针对2020年8月6日甘肃省宕昌县沙湾镇水峪沟暴发的近40年来最大规模泥石流，通过现场踏勘，分析泥石流的形成条件及特征。运用FLO-2D软件，模拟5 %、2 %、1 %的降雨频率下泥石流流动过程，得到不同频率下水峪沟泥深、流速分布图，并基于泥石流强度进行危险性分区得到不同频率下危险性分布。在1 %降雨频率下，模拟得出最大流速8.36 m/s、最大泥深26.1 m，模拟精度因子为68.6 %。

Hazards Analysis of Debris Flow in Shuiyu Gully of Bailong River Basin

Aimming at the largest mud-rock flow in the past 40 years in Shuiyugou caused on August 6, 2020, in Shawan Town of Tanchang County of Gansu Province, the formation conditions and characteristics of the debris flow are analyzed by site survey. FlO-2D software has been used to simulate the flow process of debris flow under the rainfall frequencies of 5 %, 2 %, 1 %, and the distribution maps of mud depth and flow velocity have been obtained, and the risk distribution of debris flow at different frequencies has obtained based on the risk partition of debris flow intensity. At 1 % rainfall frequency, the simulated maximum velocity is 8.36 m/s and the maximum mud depth is 26.1 m, the accuracy factor is 68.6 %.