基于DAN3D的五花海泥石流运动过程模拟研究

Study on the Simulation of Debris Flow Movement Course in Wuhuahai Based on DAN3D

2017年8月8日九寨沟景区发生7.0级强烈地震,地震诱发景区内多处崩塌、滑坡、泥石流等地质灾害。五花海泥石流沟口正对五花海景点,地震诱发沟域内产生大量崩滑、震裂松散物源,一旦遇到强降雨,可能形成泥石流冲出沟口,对五花海景观造成强烈破坏。本文通过DAN3D软件对泥石流进行数值模拟,预测了泥石流50 a与100 a一遇的运动过程,可以得知50 a一遇工况下泥石流不会大量冲出,少量冲出泥石流会对栈道构成一定威胁。100 a一遇工况下,泥石流浆体大量涌出,泥沙大量冲入五花海,会对五花海景观水质构成严重威胁。根据模拟结果,提出了“拦挡物源、围堰停淤、拦水过滤”的防治建议。

On August 8,2017,a strong earthquake with magnitude of 7.0 occurred in Jiuzhaigou scenic area,which induced many geological disasters such as collapse,landslide and debris flow in the scenic area.The outlet of debris flow is facing the scenic spot of Wuhuahai.A large number of landslides and seismic cracks are generated in the gully area induced by the earthquake.Once encountering heavy rainfall,debris flow may rush out of the outlet of the gully,causing strong damage to the landscape of Wuhuahai.In this paper,the numerical simulation of debris flow is carried out by DAN3D software,and the movement course of debris flow in 50a and 100a return period is predicted.It can be seen that under 50a return period,debris flow will not rush out in a large amount,and a small amount of debris flow will pose a certain threat to the trestle road.Under the condition of 100a return period,a large amount of mud flows out,and a large amount of sediment flows into the Wuhuahai,which will pose a serious threat to the landscape water quality of the Wuhuahai.According to the simulation results,the prevention and control suggestions of"retaining material source,cofferdam silt retaining and water blocking filtration"are put forward.