Research on urban block waterlogging simulation based on coupling model of SWMM and LISFLOOD-FP
In order to evaluate the evolution process of urban block waterlogging disaster when encountering rainstorm under the highly urbanized construction,a typical drainage division of the Qinghe River Basin in Haidian District of Beijing was selected as the research object,and a hydrological-hydrodynamic coupling model based on SWMM and LISFLOOD-FP model was constructed.Three measured rainfall events,P20210712,P20210718,and P20210823,were selected for model parameter calibration and validation.P20210703 measured rainfall was selected for model application,and long-term(24 h)rainfall scenarios with rainfall return periods of 10,20,30,and 50 a were selected for waterlogging simulation analysis.The results show that the Nash-Sutcliffe efficiency coefficients of the model under three measured rainfall conditions are 0.76,0.68,and 0.71,respectively,indicating that the model parameters are set reasonably.Under the condition of P20210703 measured rainfall,the simulated inundation range and depth of the model are in good agreement with the actual observation,indicating that the coupled model has high accuracy.Under long-term design rainfall scenarios with four different rainfall return periods,the number of overflow nodes and the total amount of overflow both increase with the increase of rainfall return period.The submerged area with a depth greater than 1.00 m increased from 0.024 km2 with a rainfall return period of 10 a to 0.345 km2 with a rainfall return period of 50a,mainly concentrated in lower concave bridge areas of Shangdi Road,Anningzhuang West Road,Anningzhuang Middle Street,Anningzhuang Road,etc.,which are in good agreement with the observation results.