基于SWMM模型的沿海城市内涝模拟研究

沿海地区台风过境时的短历时强降雨可迅速形成地表径流,易导致城市内涝,造成严重的经济损失和人员伤亡。为缓解该问题,本文以福州晋安河流域为例,构建了基于SWMM管网和地面二维积水的城市内涝模拟模型,以研究该区域城市内涝成因及应对策略。实例研究表明,上游库湖泄水抬高内河水位,下游外江涨潮使内河排水不畅,是形成内涝灾害的主要原因。为此提出库湖闸站联合错峰调度方案,有效防止下游江水倒灌。以苏迪罗台风降雨为例,采用该调度方案可减少管网节点溢流量27.44%,缩小淹没面积29.73%,降低内涝严重区河道最高水位1.02 m,有效缓解地表淹没。本研究成果可为福州城市内涝的科学调度提供技术支撑,同时对其他沿海城市的防洪调度具有参考价值。

Research on urban flooding simulation in a coastal city based on SWMM model

When the typhoon passes through the coastal area, the short duration of heavy rainfall quickly forms the surface runoff,resulting in serious economic losses and casualties. Aiming at alleviating the prob-lem, this paper took the Jin''an River Basin in Fuzhou City as an example and established a waterlogging simulation model based on SWMM pipeline network and 2D ground flooding to study the causes and coun-termeasures of urban waterlogging in that area.Based on the simulation results,the discharge from upper res-ervoirs raised the river level and the tidal level in lower reaches impeded the drainage of the river, which results in waterlogging disaster. In view of the above causes, a joint peak staggering regulation scheme of the reservoir and lake sluice station was proposed to prevent the backflow of the downstream river water, reducing the total spillover flow of the pipe network nodes by 27.44%, the submerged area by 29.73%, and the maximum water level of the river channel in the serious waterlogging area by 1.02m,and effective-ly alleviating the surface submergence. The results of this study can provide technical support for the scien-tific regulation of urban waterlogging in Fuzhou., which has important reference value and guiding signifi-cance for flood control and regulation in other coastal cities.