To simulate the influences of road surface runoff and drainage system overflow on road waterlogging, 2D surface runoff model is adopted for road catchment areas, 1D model is adopted for other catchment areas and underground pipe networks, and then a 1D and 2D coupling waterlogging model is developed based on PCSWMM. A quantitative source analysis method for road waterlogging is also proposed, which takes the contribution ratio of surface runoff from local road or overflow from drainage system to road waterlogging water as the indexes. After calibration and validation based on the measured water level in the manholes and the measured waterlogging depth on the road, the model is used to simulate the road waterlogging in a drainage area of Nanshan District of Shenzhen City under designed storm events. The results indicate that there are four main road waterlogging points (A, B, C, D) in the study area; overflow occurs on two points (A, D) under the storm event with a return period of 5 years, the overflow volume accounts for 24% and 61% of the total volume of waterlogging water respectively; while overflow occurs on three points (A, C, D) under the storm event with a return period of 50 years, the overflow volume accounts for 49%, 62%, and 73% of the total volume of waterlogging water, respectively; and the contribution of the overflow volume from manholes to the total waterlogging volume increases as the storm intensity increases. The dynamic change of road waterlogging is comprehensively affected by many factors such as the sources of waterlogging water, downstream blockage, local terrain and so on. For the waterlogging points where overflow volume accounts for a large amount of waterlogging water, it is recommended to improve the drainage capacity of the drainage system and promote the sponge city construction in the upstream catchment; for the waterlogging points where the local road surface runoff volume accounts for a relatively large amount of waterlogging water, it is recommended to promote the sponge city construction in the local area, and properly modify the local terrain or increase pump stations for drainage. 

为模拟道路地表径流和排水系统溢流对道路积水的影响, 对道路汇水区采用地表二维模型, 对其他汇水区和地下管网采用一维模型, 并构建基于PCSWMM的一二维耦合内涝模型, 提出以本地道路地表径流和检查井溢流对积水贡献比例为指标的积水来源定量分析方法。基于实测检查井液位数据和积水深度数据对模型进行验证后, 利用该模型对设计暴雨条件下深圳市南山区某排水片区的道路积水进行模拟, 得到如下结果。1) 研究区存在4个主要道路积水点(A, B, C和D), 在重现期为5年的暴雨下, 有两个积水点(A和D)发生溢流, 溢流在积水中的占比分别为24%和61%; 在重现期为50年的暴雨下, 有3个积水点(A, C 和D)发生溢流, 溢流在积水中的占比分别为49%, 62%和73%。随着暴雨强度增大, 检查井溢流对积水的贡献增加。2) 道路积水的动态变化受到积水来源、下游壅堵和局部地形等诸多因素的综合影响。3) 对于溢流在积水中占比较大的内涝点, 建议着重提高管网排水能力, 并对上游汇水进行海绵化改造; 对于本地道路径流在积水中占比较大的内涝点, 建议对本地进行海绵化改造, 适当地改造局部地形, 或增加排涝泵站等设施。