Research On The Modeling Of Rainwater System And Intercept Control Technology

The rainwater plays a significant role in the nature. It is a vital pathway for people to obtain fresh water. 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, which provides a new strategy and method for urban rainwater management. Therefore, the apply of computer model to study rain intercept control technology is of great significance to deal with the flood.On the basis of instances applying and consulting rainwater management at home and abroad, research analyzes the concept and types of rainfall intercept control technology, chooses the combination of LID source control and storm detention tank as key research project technical means. Considering the different effect of different rainwater management measures, summarize 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 rainwater intercept control measures from the sewage interception, economic, social and urban microclimate four aspects.On the basis of analysis rainwater simulation and management technology achievement 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 new city region of JZ, and validate multiple hydraulic parameters to determine the model parameters in the study area. Through dry running under different rainfall reappearing period, analyze the present situation of rainwater system export status, surface runoff, node overflow and pipeline overload, come up with the pipe network optimization scheme of both changing node elevation and increasing the diameter of pipe network to realize the normal operation in the rain spell and provide technical support to study rain intercept control measures in the next step of research.On the basis of the simulation analysis, combining with the land use planning, the analysis of LID single measure suitable for the study area turns out that the permeable pavement, low elevation greenbelt, rain garden and rain barrels have certain efficiency on sewage intercepting, and it is identified that the rain garden has the highest sewage interception efficiency value according to the benefit of quantitative evaluation method, and then as the optimal LID single measures of the study area the rain garden is composite designed with detention tank in different position.Finally, the comprehensive benefit quantitative analysis of four kinds design scheme according to the comprehensive benefit evaluation system shows that combination scheme(the rainwater garden plus permeable pavement plus detention tank at the end of the pipe network) achieves the highest comprehensive benefit value and can be used as the primary choice of stormwater management in the study area. The results can offer technical support for stormwater management and municipal engineering plan in the new town of JZ, at the same time, demonstrate the feasibility of the evaluation system and provide decision-making for the design of similar projects.