Modeling And Application Of Multi Mode Rain Water System Based On Parameter Measurement

With the development of the city,the increase of the impervious surface percentage and the runoff lead to the more severe floods,while the O ld Town combined sewer system renovation was a major problem;Moreover,the reduce to green land lead to intercept less organic matter,so carrying a large amount of rainfall pollutants would overflow into and pollute the river seriously.Therefore,new storm water management concepts which reduced the transformation of the old city and the new urban rainwater pipe network cost,so the new concept “LID” is proposed.In the selection of the Jiao Zhou rainwater system as the research background,Studying SWMM model and Hongye municipal pipeline 9.0 imported technology was used to construct five models rapidly,including status,conventional model,join the rain garden development model,join the permeable pavement development model and combination LID development model.The key to the accuracy of model was up to calibration of the parameters.The parameter of hydrological and Water quality modules was evaluated with three different intensities of practical rainfall based on disturbance analysis method.The results showed that the descending order of parameter sensitivity to peak flow was N-imperv,Des-imperv and Des-perv in hydrology.In water quality,the max buildup,rate constant of road and roof parameters had higher sensitivities to COD peak concentration in pollutant accumulation module.The result of five calibrated model was used to compare the difference,the results indicated that runoff coefficient,peak flow,overload manholes and pipe number and organic emissions in the conventional model had increased compared with the status,and the low-impact development mode had decreased with status and conventional model;For the storm water control effect of different LID model,Combination LID> Permeable Paving> Rain Gardens;The stronger the rainfall intensity was,the sooner and greater maximum organic emissions in low-impact development model was.Dealing with the initial rainwater had become an important research direction in low-impact development model;In terms of economic and social benefits,LID had a great advantage over conventional retrofit programs.This topic research provides technical reference for rainwater pipe network transformation and provides a certain theoretical basis for sponge city construction.