Development And Application Of The Storm Flood Computation Model For Urban Storm-water

With the development of urbanization, the impervious areas have become are increasingly lager arousing the decreasing of the runoff duration and the increasing of the discharge quantity, So the the flood prevention problem has became a hot topic. Being considering few factors, sometime the traditional rational runoff formula applied to the urban rainfall runoff modeling is not satisfied with the demand of design.On the basis of analyzing urban hydrological character properties and summarizing forepassed productions, one urban rainfall runoff simulation model is proposed , with which the observed discharge hydrograph can be simulated . In the model, the temporal distribution of rainstorm is calculated by using K.C method, the runoff yield in impervious areas is computed by using the isochronal method, while in pervious areas by using Horton Infiltration formula, the surface flow concentration is calculated by utilizing time-contour method and the pipe network flow concentration by utilizing Muskinggum method. A case in Yahua neighborhoods in Changsha is discussed by using the model proposed in this paper , of which the parameters of the model were calibrated and verified, The results show that the model has a good precision. The achievements of this paper can be regarded as a mean of urban rainfall runoff simulation.