Numerical Simulation On Urban Flood Based On MIKE FLOOD

With the rapid development of China’s economy and the accelerating process of urbanization,the type of land utilization changes from the permeable to impermeable surface,which resulting in permeability under the pad surface increased rapidly,surface water infiltration decreased,to speed up the convergence of surface water flow.In addition,along with the global climate warming,locally heavy rain and heavy rain weather,extreme climate and frequent.What’s more,the cases of short-term rainfall breaking a record of historical peak are becoming more and more.The last but not least,urban waterlogging even becomes a ordinary phenomenon.Therefore,carrying out the research of simulation of city storm water has a great significance for the construction of city flood control project.What is critical to the establishment of early warning system of waterlogging disaster assessment is conducting a comprehensive simulation.In terms of general urban drainage pipe network simulation software,those only simulate the one-dimensional water flow process of the drainage pipe network,but it has rarely studied the situation of urban surface water and the process of this aspect of the simulation.In this thesis,i build one dimensional drainage network model and two-dimensional overland flow model by the Mike flood model platform,which simulate respectively the long and short duration of two different rainfall distribution process.I evaluate the assessment of waterlogging risk in the study area by the waterlogging simulation method.Then in put forward the measures of improvement according to the different risk areas,and analyses different phenomenon’s caused by retrofit schemes in different rainfall return period,including discharge flow changes,node overflow,and water depth situation.According to MIKE Flood model,we analysis different results for reform project show that there are great variances in different rainfall return period and respective reform scheme.Green transformation measures make greater relief to drainage pressure in low rainfall return period,then make the peak time hysteretic and make peak flow lesser.Gray transformation measures of reservoir storage volume possible can largely reduce the pipe downstream flood pressure,but it has little effect to upstream pipe.Above all,the combination of gray transformation measures and green transformation measures can play effectively.