Sponge City Rainwater Pipe Network Optimization Research Based On Analysis Of Waterlogging Risk

The process of civilization leads to a great change to environment in urban area and its surroundings,and also changed the natural climate and hydrological condition in city seriously with the seriousness about road harden,the decrease of the rain intercept vegetation and the renovation of the original river.In the case of persistent rainfall or the sudden heavy rainstorm,the insufficient ability about urban pipeline drainage system,poor storage capacity and congestion of river channel will lead to a serious situation which unable to discharge the water on the ground in a short time,and ultimately results in heavily urban waterlogging.The emergence of urban waterlogging has a bad impact on normal life and production,even seriously threaten the safety of people,and causes a huge loss to economy of the country.The risk study of urban waterlogging combine with hydraulic model,as well as the optimization bout drainage system based on risk study and sponge city construction have a strong practical significance.This paper compares the existing method of urban waterlogging risk assessment and drainage system optimization,introduces the basic idea about urban rainwater drainage system and waterlogging prevention system,details the basic principle and calculating method of Fuzzy Variable Model.A drainage system in Hefei City is established and taken as an example,evaluate the result of hydraulic simulation using waterlogging risk evaluate model,and on this basis we are supposed to go deep into study the optimization method in pipe network hydraulic performance and economic effect.In addition,this paper discusses the rationality about the method to determine the total annual runoff volume control at present from the angle of runoff coefficient,the influence of sponge city construction in rainwater pipeline network optimization,the method of controlling index selection and decomposition,also explores the applicability in construction scheme where there is a difference in spatial scale range and network rationality.The results propose appropriate advice and implementation method for new town construction and provide new idea for the urban waterlogging solving in old town.