Research On Numerical Simulation Of Flow Characteristics Of Debris Flow And Model Of Comprehensive Treatments

Debris flows are the most common natural disasters in mountain area, which erupted suddenly and damaged extremely. With the rapid economic development, human activities continue to expand into the mountains and conflicts between debris flow and humans become more acute. Since the last century, scholars from various countries have done a lot of researches on debris flow. Currently, the debris flow researches include studies of several aspects of debris flow fluid model, forecast and early warning of debris flow, mudslides disaster assessment, numerical simulation of the flow characteristics of debris flow and debris flow research in prevention and treatment of various types of structures.Mountain area in China is vast, and makes China be a country which has most active debris flows, especially in the western region, human’s life and property damaged a lot. In order to achieve the purpose of disaster prevention and mitigation, this study did a research on debris flow’s characteristics and control structure in Shangzhuo Valley of Zhuoni County in Gansu Province, in order to provide references for subsequent studies. The main contents are as follows:(1) This paper discussed and analyzed the internal and external factors which make mudslides formed. Also, start and formation conditions of common debris flow, starting conditions of stone stream water containing fine particles,formation conditions of mud flow, and formation conditions of viscous debris were analyzed.(2) Numerical simulation of the basic theory of debris flow that computational fluid dynamics and computational fluid dynamics numerical methods were discussed, and three-dimensional fluid turbulence model and two-phase flow simulation methods were studied.(3) With the help of AUTOCAD,3dsMAX, RHINO, and other modeling software, a three-dimensional terrain model of Shangzhuo valley and flow model were established on the use of Shangzhuo valley’s three-dimensional contour map.(4) Bingham fluid model was chose, and with the help ofCFX fluid analysis software, a three dimensional numerical simulation was contacted on debris flow of Shangzhuo valley based on reasonable boundary conditions and control parameters.After gaining flow rate and pressure of flow field data, and by using ANSYS analyzing software, a two-way fluid-solid coupling on debris flow and blocking dam was contacted under the two situations:full library over current and gradually silting to the full library over current, as a result, this study got the debris flow variation motion of blocking dam and dam of sand’s stress and strain and displacement under load of debris flow, with a view to provide references and recommendations for subsequent project’s management.(5) Based on field research of debris flow in the south of Gansu province and numerical simulation of Shangzhuo valley on the structure of prevention, it was found thatthe existing structures have a lot of problems, such as the form is single,and several typical model of comprehensive treatments were proposed,in order to control debris flow in a more effective way.