Study On Flow Simulation And Visualization Of Debris Flow Check Dam

Construction of silt dam is one of the debris flow disaster prevention and control of the frequently used in geotechnical engineering measures,by reducing the amount of debris flow,solid to reduce the harm of debris flow gully bed,debris flow to stop moving along the channel check dam,involve dam library opening occlusion,piled up in the front of the dam,with the dam process,such as debris flow silt dam flow simulation can quantitative analysis of the block effect,better to make a scientific design,dam flow visualization can intuitive understanding to the dam running effect,aided engineering design.In this paper,field investigation,theoretical analysis,model test,engineering application and other research methods are adopted.Based on the theory of debris flow dynamics,the typical dam overflows are analyzed.Debris flow movement to the dam,according to dam opening occlusion problem,the grille dam block probability model is deduced,and based on the theory of machine learning,puts forward the nonlinear discriminant window dam block degree,to establish a different type of dam accumulation model in the front of the dam,implements the mudslide silt dam flow numerical simulation,and the development of simulation platform as the research output,used in engineering design,through the digital computer aided to improve the efficiency of engineering design personnel.Preliminary conclusions are drawn as follows:1.Convergence of the motion model algorithmWe consider the Mass flow model as a basic control of debris flow movement equation,construct the finite difference scheme to solve motion model,the motion simulation of debris flow in the channel,in order to guarantee the convergence of algorithm is build difference scheme,demonstrates the consistency and stability,namely the difference scheme of error propagation equation,the growth factor for any any grid than meet the Von Neumann condition,ensure the convergence of calculation process.2.Block model of the opening of debris flow barrier damDebris flow front end(tap)concentrated near the biggest diameter of particle,the part of the particles in a random time interval to mesh opening,grille dam at the opening of occlusion by opening width and the influence of particle diameter ratio,in the numerical simulation of opening occlusion,every time need to debris flow and time of arrival to do a large particles,abstracts the concept of an average time of arrival,and make blocking probability estimates,for each particle to get the average time required until occlusion of infinite series,and derive the average time of opening occlusion with each moment closed the mathematical expression of probability,step by step a large particles To solve the problem of grid dam block;In window criterion of dam block degrees,in this paper,the advantages of high accuracy based on machine learning classification,based on the indoor model test,will affect the occlusion of multiple index as the training sample,through changing highdimensional data processing,improve the classification accuracy of 6%,by machine learning theory to establish the occlusion of multiple factor nonlinear function model is feasible,compared with using original data fitting out the experience formula of the more optimized,window dam block type discrimination more accurate;The blocking of incisional dam is mainly related to the ratio of the diameter of large particles in debris flow to the width of the opening.3.Calculation of accumulation rate in front of damEntity gravity dam can't timely discharge debris flow,landslide impact silt dam,the distance between particles can dramatically smaller,the friction between the particles will increase,the debris flow will suddenly stopped,or near the bottom velocity is small,gully bed shear stress increases,debris flow deposits,will be carried out in the inflow of debris flow moment accumulation in front of the dam,the numerical simulation,the thought,at the boundary of accumulation is the fastest,stacking velocity is mainly manifested on the accumulation of large particles,and the solid dam dam before the rapid deposition was not the simple accumulation of gully bed formula to solve,needs a large particle concentration in the front of the dam,can calculate the accumulation rate;The stacking rate of each layer is related to the mud flow depth and the transverse lattice structure size of the grid dam.The accumulation rate of incisive dam is inversely proportional to the size of the openings in the dam body,and the flow rate of debris flow is proportional.4.Silting model of full reservoir of dam bodyAfter full library of the dam body,the back silting height mud-rock flow is often higher than the high dam,slope and form back silting,silt dam of gully bed height below the dam crest height,the dam is configured to debris flow,when higher than the height of dam crest,you need to calculate point distance(dam)fastest accumulation rate of deep mud,elevation,the back silting height here would be a simulation of back silting maximum height,and according to the horizontal distance((35)x/ 2),vertical elevation difference((35)z)to find the back silting slope.5.Engineering application effect of visual platformCompilation of debris landslide dam flow simulation platform can satisfy the real dam,grid calculation of dam,dam of incision,by setting the observation point to reflect on the dam body,downstream of the debris flow physical parameters change,the more intuitive reflects the regulatory effect of silt dam,the digital computer aided design and improve the efficiency of the engineering design,and engineering application of numerical simulation is a new kind of method,prevention and control of engineering reasonably calculate the related parameters to better scientific design of silt dam Lan Dang performance is good,better guarantee the people's life and property safety.