Research On Waterlogging Prevention And Control Facilities And Combination Based On SWMM

In recent years,with the speeding up of urbanization in our country,the impervious area of city underlying surface increased,causing flood becomes frequent,which threatens people's normal life and normal function of the urban,in the meantime,the development of computer technology promotes the birth of rainwater pipe network model,LID measures are increasingly used in urban waterlogging management,learn from the concept of foreign major drainage system,China has also paid more and more attention to the construction of drainage and flood prevention facilities.Therefore,the apply of computer model to study measures of waterlogging prevention and control and their combination is of great significance to deal with the flood.The main contents of this paper are as follow:(1)On the basis of consulting relevant literature,introduce the types of flood control facilities,chooses the combination of LID source control and drainage facilities as key research project technical means.Summarizing the typical measures of different benefit index,propose the benefit identification method based on analytic hierarchy process(AHP),and establish a set of overall efficiency evaluation system of combination measures from the runoff control,economic,social and urban microclimate four aspects.(2)On the basis of analysis rainwater system modeling technology at home and abroad,discussed and analyzed the rainwater system modeling technology,through the contrast analysis choose SWMM to model the current rainwater pipe network in the Qingshan Lake area in Nanchang,and validate multiple hydraulic parameters to determine the model parameters in the study area,through simulation running under different rainfall reappearing period,analyze the present situation of rainwater system surface runoff,node overflow and pipeline overload,provide technical support to study prevention and control measures of internal waterlogging in the next step of research.(3)On the basis of the simulation analysis,the analysis of drainage single measure suitable for the study area turns out that rainwater pumping station,rainwater storage tank and rainwater discharge channel have certain efficiency on runoff control,and it is identified that the rainwater discharge channel has the highest runoff control efficiency value according to the benefit of quantitative evaluation method.the analysis of four kinds of combination of programs turns out that the combination scheme achieves the effect of overall and local double control of waterlogging risk,having obvious advantages.(4)The comprehensive benefit quantitative analysis of four kinds design scheme according to the comprehensive benefit evaluation system shows that combination scheme(low density LID facility+rainwater discharge channel+ rainwater storage tank)achieves the highest comprehensive benefit value and can be used as the primary choice of waterlogging governance in the study area,the optimal scheme can reduce the control water level of Qingshan Lake,to improve the overall drainage capacity,summed up the waterlogging control technology strategy of the old city,"to save,row mainly to seepage as the auxiliary".The results can offer technical support for waterlogging governance in the Qingshan Lake area in Nanchang,at the same time,demonstrate the feasibility of the evaluation system and provide decision-making for the design of similar projects.