南京城市降雨淹没模拟及径流分析

针对强降雨引起的城市积涝以及相应次生灾害等问题,提出了一种基于暴雨洪水管理模型、GIS技术以及DEM数据、排水管网数据、降雨数据等数据的建立南京市暴雨积涝模型的方法,并利用该模型模拟了径流及淹没效果。结果显示:该模型是利用经验值率定方法对模型参数进行率定,率定结果较为符合实际情况,因此该模型能较好地模拟南京市的降雨积涝情况。通过对不同类型的降雨数据进行模拟分析,得出径流量的大小与降雨量强烈正相关,相关系数达0.9以上。径流的产生量还与降雨历时和平均降雨强度等其他因素有关。虽然南京主要降雨为峰值小、平均强度低的小雨,但是当降雨量超过设计排涝能力时,在地势低洼的地区容易出现积涝。

Waterlogging simulation and runoff analysis of urban rainstorm for Nanjing

Regarding present problems of waterlogging and secondary disaster caused by rainstorm,one method to build Nanjing rainstorm waterlogging model is introduced.Based on SWMM(Storm Water Management Model)and GIS techniques,DEM data,underground pipeline data and precipitation data,Nanjing rainstorm waterlogging model are built and model actual parameters are got by parameter calibration.It is found that this model's actual parameters and corresponding outputs are reasonable good and can well reflect actual situation.The runoff and the number of waterlogging points increase as the recurrence period grows.Actually,runoff volume is strongly correlated with precipitation volume with correlation coefficient over 0.9.It is also found find that the most probably occurred rainfall in Nanjing is light rain with low intensity and low volume,while the precipitation volume exceeds designed drainage capacity,waterlogging occurs.