Study On The Suitability Evaluation And Design Method Of Sponge City Construction

With the rapid development of city,underlying surface has changed hardening,the frequency of waterlogging has increased.Sponge city is an important measure to solve the current problems of urban development.Sponge City is a national strategy for urban development in China.It requires scientific quantitative analysis during construction,and proposes a reasonable design plan for the characteristics of the region.In view of the existing problems in the construction of sponge city,this paper quantitatively studies the suitability of sponge city construction and provides a scientific basis,which is a great significance for sponge city.The main research content of this article is:(1)Based on the relevant concepts,theoretical basis and evaluation principles of the sponge city construction suitability evaluation,the suitability evaluation method of sponge city construction was studied.Based on the principle of index selection,eight suitability evaluation factors are ultimately selected.AHP was used to determine the factors weight,and ArcGIS software was used to obtain evaluation results.The study area is divided into 3 kinds of area: restricted construction area,conditional construction area and suitable construction area.(2)For the conditional construction area and suitable construction area,the article constructs the method of design for sponge city.Reviewing the characteristics of the area and existing problems,the conditional construction can be further divided into low construction density sponge restoration area and sponge upgrading area,the suitable construction area can be divided into high construction density sponge restoration area and water ecological protection area.The article proposes sponge city control requirements,technical measures,etc..(3)Taken the Qingshan Lake drainage flood control area in Nanchang City as the research object,the assessment of the suitability of the sponge city construction was conducted,and the sponge city design scheme was proposed.The SWMM model was used to simulate the effect of runoff control under different scenarios.Analyze the simulation results that the sponge city program reduced the runoff coefficient,reduced the peak runoff,delayed the peak time,reduced the number of overflow nodes and reduced the pipeline load.Through the construction of Sponge City,under the conditions of one-year rainfall in the study area,the annual total runoff control rate is 71.5%,which meets the total runoff control target and can effectively alleviate urban stormwater problems.