Rainstorm Water-logging Origin Analysis And Simulation Study Of Xi’an Typical Area

Along with the global climate warming increasingly and large-scale urbanization progress, the urban water cycle changes greatly. Frequent rainstorm weather appears in many large and medium-sized cities in recent years, local short duration storm makes urban drainage system in serious paralysis. Storm water floods roads and houses, which causes people great life damage and property loss.Xi’an City has large-scale development progress in recent years, but city drainage system construction lags behind the city land development, every summer rain will form the urban water-logging. Based on Xi’an severe rainstorm water-logging situation at present, analysis the cause of Xi’an rainstorm water-logging, combine with the characteristics of the typical water-logging area, apply with SWMM to simulate and analysis the typical area of rainwater pipe network. In this paper, the main research results are as follows:1. Review draining and prevent water-logging situation and the research progress of urban water-logging model at home and abroad. Tell basic general situation of the geography, climate, soil and rivers about Xi’an City. Enumerate Xi’an rainstorm water-logging phenomenon and serious influence in recent years. Analyze and summarize the causes of urban water-logging systematically.2. Introduce the development and the principles of SWMM, specify the scope and use of SWMM, data preparation, using steps and modeling route. And analyze the applicability of the model in the study area. Apply synthesis of Chicago rainstorm process line, design typical heavy rains. Combined with the topography, the trend of the pipeline, the condition of different land use and the ground slope in the study area. The rainwater pipe networks are generalized in the study area. Select appropriate model parameters, preset parameters and continue debugging model to preferences, set up a typical area of SWMM.3. Put forward the evaluation method of rainwater pipe network drainage capacity. Through the network operation under different heavy rains return period, Analysis of overflow condition of inspection wells and drainage pipeline operation load. Combine with the dynamic display of SWMM to analyze system of operation. Find out network performance bottlenecks, and put forward reasonable suggestions.The results show that Xi’an rainstorm water-logging origin have focused on global climate change, urban construction of surface hardening, low standard of departed planning and design, lack of drainage system construction and maintenance, improper operation of management measures, etc. SWMM of rainwater pipe network simulation has good applicability in the study area. Evaluate rainwater pipe network capacity by the simulation results, rainwater pipe network bottleneck identification and the region can be adapted to provide technical support, which can give the Xi’an water-logging warning system and urban disaster prevention and mitigation a certain practical value.