大尺度无管流数据城区SWMM构建及模拟——Ⅱ.模型参数校验及暴雨径流模拟分析

目前,中国城区大多缺乏实测管道流量数据,给城市水文模型构建及精细化模拟带来了挑战。在北京亦庄经济开发核心区下垫面精细数字化的基础上,以典型点的最大径流深为验证要素,以实地踏勘为主、经验率定为辅,分别选取2012年"7·21"和2011年"6·23"两场典型大暴雨径流过程,完成了区域SWMM(Storm Water Management Model)模型的参数率定和验证;并就不同重现期设计暴雨下,不同典型用地子汇水区的产汇流响应特征及内涝交通拥堵风险进行了分析及评估。结果表明:随着重现期的增加,道路与交通设施用地对暴雨增幅的响应速率远高于公园绿地的响应速率,前者的内涝交通拥堵风险亦远高于后者;间接反映了不同下垫面条件造成产汇流响应的差异程度。相关成果可为区域城市洪涝管理与预警提供决策参考。

SWMM-based rainfall-runoff simulations in large-scale urban area with no pipeline-flow observations: Ⅱ: model calibration and analysis of rainfall-runoff simulations

At present,many cities in China are short of pipeline-flow observations,which leads to large challenges to construct urban hydrological models for detailed rainfall-runoff simulations. In this study,the core district of Yizhuang Economic Development Zone was selected as the study area. Based on the accurate digitalized land-surface data,field survey and empirical verification of urban storm process was carried out in terms of the maximum runoff depth at specific spots,and the SWMM model was calibrated and verified for the two typical storm events in July 21st,2012 and June 23rd,2011. Subsequently,the runoff response rate and traffic congestion risk of design rainstorms in different return periods were analyzed and evaluated in sub-catchments with various land-uses. The results show that as return period increases,street and transportation land-uses have a higher response rate to the increase of rainstorm than park and green land-uses do,and the former has a higher risk of waterlogging-triggered traffic congestion than the latter. This finding indirectly reflects the variability of runoff response rates under different land-surface conditions. This study is potential to provide decision-makers with valuable suggestions on effective local urban-flood control and early warning.