Research Of Urban Flood Simulation System Based On Multi-Source Information

The number of urban flood is increasing in recent decades due to the rapid urbanization and extreme climate events,which has seriously threatened human security and economic development.Therefore,it is significant to develop urban flood model to carry out efficient and accurate predictions of flood processes.A large amount of basic data was required to establish urban stormwater model,such as rainfall data,topographic data,urban underlying data,and node network data.The collecting and managing of model-based data has become one of the hottest research hotspots in the development of urban stormwater models.At the same time,the rapid and timely display of the results of the urban rain-flood model in a reasonable and effective manner is also of great significance for the evaluation and analysis of floods.At present,it is necessary to develop an effective integrated urban storm flood simulation system with multi-source information coupling technology to improve the efficiency of establishing model.A literature review was done for hydrological and hydraulic methods and models in flood study.The development history and current research status of the application and development of urban rain-flood models based on geographic information technology and multi-source information coupling technology was also presented.The work for this research was summarized in the following ways.First,based on the online map platform,basic data of the stormwater model was collected.The latitude and longitude coordinates,area,feature width,and other geographical attribute data of the catchment area of the stormwater model are extracted.Using high-definition satellite maps and urban land classification maps as data sources,based on the HSV threshold segmentation algorithm,the urban surface land properties were extracted;the Google Earth Digital Elevation Model(DEM)was used as the data source to extract urban landforms.Second,overflow flood was simulated.Based on DEM data,D8 algorithm,seed propagation method and equal volume method will be used for flooding simulation overflow of pipe.The distribution and depth of waterlogging was calculated and displayed by online map.Third,online map was used as the main development platform based on JavaScript,Python,and C# programming languages to develop a multi-source information urban storm simulation system.The multi-source information urban storm flood simulation system couples multi-source information such as rainfall data,high-definition satellite maps,urban land classification maps,topographic data and drainage network data.Fourth,the muilt-source urban flood system was applied to the flood simulation in the southern city of Jianye District,Nanjing.Based on multi-source information such as regional node pipe network data,DEM data,and online HD map data,the flood process of different return period rainfall was simulated and the simulation results were subjected to a second simulation calculation to achieve a detailed simulation of the urban stormwater accumulation and the results display.Finally,a summary is given and some problems to be further studied are discussed.