Study On Site Optimization Design About Waterlogging Area In Beijing Inner City Under The Perspective Of Sponge City

Along with the advancement of urbanization construction, traditional extensive development pattern led to the serious destruction of ecological environment of the city, then brought a series of problems, such as the urban waterlogging, the shortage of water resources. In order to realize the sustainable development of cities, the concept of "sponge city" came into being. This paper is intended to under the guidance of "sponge city" construction,through the ecological methods to solve the problem of urban waterlogging, at the same time, improving the urban ecological environment. The traditional way of solving site rain is mainly through municipal rainwater pipe network system,but now, this way have been unable to meet the drainage demand of urban waterlogging area. The root cause of waterlogging is that traditional site development pattern destroyed the natural hydrologic cycle, and the wanton spread of impervious surface lead to frequent urban waterlogging, caused huge losses.The strategies of site optimization design about waterlogging area in Beijing center city, have important theoretical significance and practical significance to solve the urban waterlogging problem and improve the urban sustainable development.The article includes five chapters. The first chapter introduces the background, purpose and meaning of the research,then, defines the concept of sponge city, urban waterlogging and site design.It elaborates domestic and foreign relevant theory and research, including low impact development theory and research, green infrastructure, sponge city that related research theory and research. The second chapter analyzes the survey results of typical waterlogging area in Beijing center city, summed up the site features and its inner texture.The features of waterlogging site mainly reflects in impermeable area, opaque surface patches, vegetation coverage and so on. Inner texture includes external cause and internal cause. Above all provides the reality basis to the waterlogging site optimization strategy. The third chapter expounds the update design strategy system about the urban waterlogging site,which including the macro, meso and micro level. The opaque surface renewal design and the update design of catchment division which in the meso-level strategy system is the innovation of this article. The fourth chapter introduces the typical application and operation steps of the stormwater management model(SWMM).The construction of sponge facilities system and the layout of the sponge facilities which put out in the micro level of the third chapter could determine through the SWMM. The fifth chapter is a practical analysis, which using the optimization strategy of urban waterlogging site on Guang Qu Men waterlogging area.