Safety Assessment Of Urban Area Under The Concept Of Sponge City

China is a disaster prone area,and every year's rainstorm and waterlogging have caused huge economic losses to the country.Since 2015,China has started to implement the sponge city construction project,which greatly alleviates the dilemma of "looking at the sea in cities"and "meeting rain and waterlogging".Around positive response since the beginning of the project,construction experimentsite area city,sponge sponge of domestic urban construction has begun to take effect in four years,but due to the construction speed is too fast,still have a lot of problems unresolved in the process of construction,based on the urban area of rain flood damage safety assessment as the main line,with sponge city based on the theory and the theory of disaster risk analysis to analyze our country's existing urban construction experience,sponge sponge from the low impact development measures of urban construction and the perspective of risk analysis of fusion,discussion about urban area rain floods of safety evaluation and optimization strategy.In the core chapter of this paper,the combination of qualitative and quantitative scientific methods,through the analysis of China's urban areas of the formation of the causes of the flood disaster,as well as the urban areas of the flood disaster factors,the vulnerability of the disaster body,the sensitivity of the disaster environment,to obtain the impact of the urban areas of the flood disaster factors.Through literature collection and risk analysis of urban area,the reference sponge urban construction control index,in view of the city area rain flood safety design of the questionnaire,using the questionnaire method,expert evaluation method and analytic hierarchy process,comprehensive analysis and preliminary build urban area rain flood harm influencing factors model,through the analysis of the results of the factor weights order to determine the evaluation index system.Based on the key research scope,selected the southeast coastal area of 24 cities area as the research object,this paper construct the urban area of rain flood harm security evaluation index system on the basis of,24 for statistical data,using principal component analysis and factor analysis,scientific analysis of the main influencing factor of the 24 cities area,and get the bearing capacity of 24 cities area rain flood harm security weighted ranking.The three principal components obtained in the analysis results are defined as sponge infrastructure demand factor,green space system guarantee factor and land use guarantee factor.According to the results of analysis,evaluation of urban area of rain flood harm security and main influence factors,in view of the analysis of rain flood harm the biggest impact of the principal component index reflects the risk factors of optimization,to guide the urban area of rain flood harm security plan,and integrate the past rain flood harm security in the city planning and city planning and construction of the commonly used sponge low impact development technology measures,put forward the system of urban area from several aspects the rain flood safety optimization.And based on the analysis of the results,based on the safety bearing capacity of 24 cities area of rain flood sort low-ranking a area are selected,further to the selected case data on the basis of risk analysis and validation,from sponge base facilities demand factor,green space system security and land use silver silver of main components of the three angles,put forward the effective promotion case for rain flood harm security capacity planning strategy,to strengthen the construction of urban sponge effect,reduce the area of the city rain flood damage risk and disaster losses.It provides a scientific and effective method for solving the problem of urban area flood disaster,improving the construction efficiency of sponge city and strengthening the safety of urban area flood disaster.