Research On Sponge Transformation Of Existing Residential Areas In Guangzhou For The Improvement Of Stormwater Resilience

The process of urbanization has changed the composition of the underlying surface of the city,and hard pavement has begun to replace the original green space on a large scale.Under the background of increasing urban rainwater runoff caused by the increasingly frequent heavy rainfall,it is difficult to absorb and purify all the rainwater by using the previous random and non-interfering rainwater drainage system.At the same time,the increase in the proportion of gray infrastructure has changed the runoff law on the surface,which has led to the formation of more urban water problems.The emergence of the concept of sponge city provides a feasible solution to this problem.However,due to the lack of effective experience,in practice,the unreasonable design of the plan often leads to the situation that the sponge measures are "unacceptable" and cannot be effective.Based on this,this study focuses on the existing residential areas in Guangzhou,takes the concept of sponge city as the theoretical guide,and actively explores a sponge transformation model suitable for improving stormwater resilience.With the help of the citespace analysis tool,this study carried out a visual analysis of key words such as sponge city and existing residential areas,and summarized and sorted out the research status and trends of stormwater management models at home and abroad.Based on the experience formed,on the basis of in-depth analysis of the characteristics of rainwater and floods and the causes of waterlogging in Guangzhou,two types of existing residential areas,including unit courtyards and commercial houses near common waterlogging points,were selected to conduct on-site surveys and residents’ cognition and transformation willingness.In order to evaluate the potential of sponge transformation of existing residential areas,the characteristics,principles,technical measures and benefits of sponge transformation,as well as the reasons and improvement strategies that affect the resilience of existing residential areas in Guangzhou,were summarized.Finally,the Swmm model was used to arrange different types and combinations of sponge facilities in an existing residential area in Guangzhou,and the simulation was carried out to verify that the sponge reconstruction was suitable for the improvement of stormwater resilience in an existing residential area in Guangzhou.