The Forming Conditions And Engineering Revention Of Yizhong River Debris Flow In Yunnan Province Deqin County

Deqin County is one of the most development of geological hazards in Yunnan Province.Through years of engineering management,the worst threat and disaster geological hazard point in the construction area of the county is the Yizhong river mud flow at present.Yizhong river is a branch of the Zhiqu river and located on the eastern side of Shengping town development area,is a mountainous area in the high frequency period of strong viscous debris flow.Yizhong river is a high frequency,viscous debris flow in the mountainous area in the exuberant stage,in 1966,1986,1997,2002,2010,the large scale debris flow disaster are occurred and the cumulative direct economic loss of tens of millions yuan,the small scale of debris flow disasters every year to produce 1 to 2 times.Debris flow threatened school and units concentrated population of about 1940 people,approximately?220 million of assets.Therefore,through the investigation,causes study and risk assessment on the Yizhong river debris flow,the prevention and control measures are put forward,which has important practical significance.Firstly,this paper starts from the geological environment conditions of Yizhong river debris flow development,and then the valley,subarea characteristics and formation conditions are analyzed in detail.quantitative study of the initiation of debris flow rainfall conditions,including monthly rainfall and maximum daily rainfall,and calculate the main kinetic parameters of debris flow.Multi factor index method is adopted to evaluate the development trend of debris flow.On the investigation,the Yizhong river is a high frequency,viscous debris flow.The activity intensity is very strong,and the disaster risk level is super.Now,it is in the period of strong and serious threat to the safety of the downstream residents and the safety of the building,and provide a scientific basis for the prevention of debris flow.Based on the formation conditions and motion characteristics analysis of Yizhong river debris flow,according to the risk and harm degree,combined with the existing control experience,proposed a comprehensive program to check dam plate pile type retailing dam + biological engineering + built retailing dam repair,respectively gives the design parameters of control engineering.Through the implementation of the project,to the effective role in prevention and treatment of Yizhong river of debris flow,the debris flow control project for high vertical drop,high viscosity debris flow area has a certain reference.