Simulation Of Urban Flood Based On Mike Under The Condition Of Extreme Rainfall

Since the reform and opening-up policy,with the accelerating urbanization process in our country and global climate changes,the extreme precipitation events frequently occur,which leads to rising urban waterlogging disasters in recent years,increasingly threating people's life safety and state property.The formation of city flood under the extreme precipitation attributes two reasons:the first one is the speeding up of urbanization that makes the city surface hardening area increased,reducing the volume of infiltration,increasing runoff amount;the second one is that urban drainage pipe network design standard is low,causing small pipe drainage capacity,and without the ability to eliminate excessive rainfall in time.Currently how to deal with urban waterlogging disasters has become one of the hottest issues of concerns from all walks of people,so the study of mechanism of urban flood hazard-formative has important practical significance and application value in the face of growing urban waterlogging disasters.The fundamental research method in this paper is to use the Mike Flood of DHI to build the model of urban rain flood,with the character combining one-dimensional drainage pipe network module Mike Urban CS with two-dimensional surface runoff dynamic module Mike 21,coupling the water of pipeline network with surface water,instead of a simple simulation of one-dimensional or two-dimensional,so urban waterlogging can be reflected in the general in study area.The main research contents of this paper are as follows:(1)The paper analyzes the current situation of the urban waterlogging,then in two aspects analyzing human factors and natural factors which induce the causes of urban waterlogging,third reviewing the research progress of urban rain flood model at home and abroad,last the research purpose and main content of this paper are clarified.(2)Introduce Mike Flood software and its components,state connecting method and the main application of the Mike Flood,one-dimensional drainage pipe network module Mike Urban CS and its sub-module,two-dimensional surface runoff module Mike 21 and its sub-module in detail,briefly explain the principle of the models.(3)Introduce the basic steps to build model in the Mike Flood,specifically and respectively present the process of building model of two-dimensional surface runoff and one-dimensional drainage pipe network as well as the combing process.(4)Taking the L city as an example,construct L city rain flood model.First use the one-dimensional drainage pipe network model Mike Urban CS evaluate the drainage ability of the city,to understand current drainage status,then simulate jacking and not jacking these two conditions of downstream river in case of flood with recurrence interval of 20 years by the coupling model,describe urban area of L city the whole process of water and their distribution under the two conditions,divide the risk level of domain waterlogged district.The cause are analyzed and corresponding measures are put forward,including engineering measures and non-engineering measures.