Study On The Simulation And Analysis Of Urban Storm Waterlogging Based On 3DGIS

Due to the rapid development of urbanization、changing of urban water conditions and deterioration of global extreme weather, the problems of urban waterlogging have become increasingly prominent. Urban waterlogging has become an important factor that endangers people’s lives and property.in the 21st century. Researching urban waterlogging to improve the accuracy of urban waterlogging monitoring and forecasting has a vital significance for the decision-making of urban waterlogging forecast and city flood control and drainage.Combining meteorology、 hydrology、geography and other related theories, with the social demand of reducing the losses of urban waterlogging and providing scientific basis for urban waterlogging warning and monitoring, this paper applies 3D GIS and modeling technology to constructing the city 3D scene of Jiading district town center for simulating and analyzing waterlogging, studies the simulation of urban waterlogging from waterlogging risk and waterlogging sensitive point on the basis of summary on theory of urban waterlogging, and associates the study results to the city 3D scene for visualization-、house、roads、disaster statistics and other disaster evaluation analysis. Eventually established waterlogging simulation and analysis system in city 3D scene relying on Jiading District Meteorological data cloud platform.The main research work of this paper is as follows:(])On the basis of summary on technology and theory of constructing the city 3D scene, this paper reasonably analyzes surface factors that affect the formation of urban waterlogging after the rain, comprehensively applies various modeling techniques to constructing the city 3D scene for simulating and analyzing waterlogging according to the characteristics and advantages of different modeling tools and techniques.(2)Refer to the idea of urban runoff model, this paper considers the influence of urban drainage system on the division of urban catchment, improves the method of determining urban catchment by traditional hydrologic analysis, constructs a runoff generation and convergence model which is suitable for the study area, designs a method based on DEM for calculating water depth of urban catchment with simple algorithm-fast calculation and high precision, achieves the calculation of regional water depth combined with water volume balance principle. On the basis of the classification standard of urban waterlogging risk level, achieving the simulation and expression of waterlogging risk of study area with GIS thematic map technology.(3)This paper comprehensively applies GIS technology and SWMM model to calculating the overflow and the water quality condition of node in the process of runoff. Extracting the sensitive point information of urban waterlogging from the results file, achieving the simulation and expression of waterlogging sensitive point of study area.(4)This paper associates the results of the simulation of urban waterlogging risk and urban waterlogging sensitive point to the city 3D scene for visualization、house、 roads、disaster statistics and other disaster evaluation analysis.(5)This paper establishes waterlogging simulation and analysis system of study area, realizes urban waterlogging monitoring、forecasting and disaster evaluation analysis, providing new idea and means for decision services of urban waterlogging forecasting and analysis.(6)Based upon Jiading district town center, this paper simulates the waterlogging risk and waterlogging sensitive point of study areas after the rain, testing and analyzing the simulation results.