低影响开发对城市内涝节点雨洪控制效果研究——不同降雨特性下的情景模拟

以中国福建省福州市晋安区解放溪流域高密度居民住宅区为例，针对不同降雨重现期、降雨历时和雨峰系数的降雨情景，利用PCSWMM模型模拟该地区的雨洪情况，并运用模型的低影响开发（LID）模块，研究7种不同LID用地布局情景对研究区内涝节点的雨洪控制效果.情景模拟结果表明：在不同降雨情景下，各LID用地布局情景会使节点的洪峰流量减小、积水时间减少、积水深度变小；植被浅沟措施和植被浅沟&绿色屋顶组合措施会使节点SS峰值浓度高于现状用地，其余布设情景下，SS峰值浓度均减小.LID措施对节点流量和水质的控制效果在低降雨重现期和长降雨历时的降雨情景下较为有效.在单个LID布设情景中，渗透铺装措施控制最佳，而组合LID布设情景中，渗透铺装&植被浅沟&绿色屋顶是最佳的组合控制措施.研究结果可为南方城市居民区实施海绵城市建设提供技术支持，并为地方制定相关规范和标准提供参考和借鉴.

Flood control effects of low-impact development on urban waterlogging node under different rainfall characteristics

This paper took the high-density residential area in Jiefangxi Basin of Jin'an District, Fuzhou City, Fujian Province, China, as an example. The PCSWMM model for storm water simulation was applied to the study area under different rainfall return periods, rainfall durations and rain peak coefficients, and the low impact development module in this model was used to study the flood control effects of seven different LID layout scenarios on the waterlogged nodes. The simulations yielded the following results. Under different rainfall conditions, the flood situation of waterlogged node in the worst affected area has been effectively controlled using single LID or combined LID layouts. The peak flow, ponding time and ponding depth decreased. The peak suspended sediment concentration of the node in vegetative swale layout and the combination layout of vegetative swale and green roof were higher than current land layout scenario, and in other layouts were under control. The reduction effects of different LID layouts were more significant under longer rainfall durations or lower rainfall return periods. Permeable pavement was the best choice in single LID layout, and the combination of permeable pavement and vegetative swale and green roof was the best choice in combined LID layouts. The research results can provide technical support for the Sponge City construction of urban residential area in the south of China, and provide reference and suggestions for local government to establish relevant codes and standards.