综合管廊雨水舱缓解城市内涝的效果分析

为了探究综合管廊雨水舱缓解内涝的效果，以广州市杨梅河为例，建立了杨梅河区域现状排水系统、现状排水系统结合综合管廊雨水舱两种工况的暴雨洪水管理模型(SWMM)，计算了4种降雨重现期下各工况杨梅河出口流量和典型内涝点溢流量。结果表明:雨水舱较优断面为宽4 m、高3.3 m，此时各降雨重现期下雨水舱对研究区总溢流量的缓解效果已达上限；综合管廊雨水舱可缓解杨梅河下游内涝，对下游两处典型内涝点的溢流量平均削减率分别为86.5%和42.2%，但对杨梅河上游内涝几乎不起作用；综合管廊雨水舱会增大杨梅河出口的峰值流量，在20年一遇降雨条件下杨梅河出口达到最大出流能力。

Effects of rainwater tank in integrated pipe gallery on alleviating urban waterlogging

Taking the Yangmei River region in Guangzhou as an example, this study was performed to explore effects of the rainwater tank in integrated pipe gallery on alleviating urban waterlogging. The SWMM models were established for cases of the current drainage system and current drainage system combined with rainwater tank. Then, the outlet flow of the Yangmei River and overflow at typical flood-prone spots were calculated under the conditions of rainfall events of four return periods. Results show that the optimal size of the rainwater tank is 4 m in width and 3. 3 m in height, with which the rainwater tank has reached its upper limit of effects on reducing the total amount of overflow in the study area; the rainwater tank can alleviate waterlogging in the lower reach of the Yangmei River, with the average overflow reduction rates reaching 86. 5% and 42. 5%, respectively, at two typical flood-prone spots in the lower reach, while the rainwater tank has little effect on waterlogging in the upper reach of the Yangmei River; the rainwater tank can increase the peak flow at the outlet of the Yangmei River, and the river outlet reaches its maximum outflow capacity under the condition of a 20-year return period rainfall.