Research On Hydrology And Water Quality Of Campus Sponge City Based On SWMM Model

Since the 21st century,China’ s urban construction is developing with a fast-paced.However,high urbanization has also brought some environmental problems.The difference between before construction and after construction of the urban hydrological cycle is the best embodiment of the urbanization nature.The construction of the city has reduced the area of the underwater surface,and the area of the impervious surface that composition by concrete and asphalt has increased,which has caused great damage to the Water cycle.Through the in-depth study and analysis of Sponge City and its related theories,combined with the example of sponge city design project in the southern part of Xianxi Campus of Foshan University,this paper explores the application mode of sponge city in the type of educational land,from hydrological water quality.And the characteristics of the campus sponge city were analyzed and summarized,and the actual application type of the sponge city was added.The main research contents of this thesis are as follows:1.This paper mainly carries out the implementation of sponge city concept on the land of campus type,including expounding and analyzing the foreign rain-flood management technology and the origin,development and evolution trend of sponge city in China,and discusses the development direction,research progress and application of sponge city in the process of urbanization in China.This paper analyzes the process from theory to application of campus sponge city.The conclusion is that the campus is suitable for the construction of sponge city due to its special land type structure,so the campus sponge city,as a part of the regional sponge city,has a strong representativeness.However,most of the current research on it focuses on the architectural landscape planning and other aspects,and few studies combine hydrology and water quality.2.In foshan science and technology college of xian xi campus south now sponge city renovation scheme of generalized of SWMM model,on the field survey of thestudy area,the hydrology and water quality model is established through analysis of the research plan,operation model,the continuity of surface runoff flow,pipe flow,water quality error between0～2%,the model has good stability and precision.According to the results of the simulation from two aspects of rainfall runoff and runoff pollution control,it is concluded that the existing scheme failed to meet the specification requirements in terms of rainfall runoff control standards,the specification requirements of the total annual runoff control 70% of the corresponding rainfall,runoff volume control in the study area can reach 65.9%,the runoff pollutant load spatial distribution,part of the pipe network design depth,load values,same before LID module Settings.3.According to the shortcomings of the existing sponge city scheme,optimize the design layout,add and expand the lid module,add a green roof module,and analyze the green roof structure and principle,the lid parameter and the layout parameter are set.In addition,modules such as sunken green spaces,rain gardens,pedestrian permeable pavements,and vehicle permeable pavements have been expanded.4.Set the new LID module parameters and area ratio and then perform simulation analysis.The model after optimization analysis has a control rate of 81%of the total runoff control rate corresponding to 70% annual runoff total control rate.From the small to the big seven return period,the control rate is from 74% to 67%,achieving a good control rate.The control effect of runoff pollutants has a large slowdown in key discharges.For example,the 70% control rate corresponds to a decrease in COD load of 9.462 kg,a decrease in SS load of 5.488 kg,a decrease in TP load of 0.064 kg,and a decrease in TN load of 0.632 kg.The material reduction rate reached more than 55% under the P=100a return period,and the runoff pollution control achieved good results.The simulation results were summarized and the conclusion was drawn: compared with the total runoff control rate of the year before the optimization,the optimized model in the research area was significantly improved,and the pollution load in water quality was significantly reduced,which proved that the model optimization effect was significant.Through the analysis and optimization of the Sponge City program of Xianxi Campus of Foshan University of Science and Technology,we try to promote the development of a campus-type sponge city project with certain universality.From the perspective of hydrological water quality,the research on campus sponge city was carried out,and the connotation of campus sponge city was analyzed from the technical level.It will promote the formation of a complete sponge city system dedicated to the campus,and provide a combination of theory and practice for the reference to the campus-type sponge city project with certain universality.The ecosystem has a facilitating role.