基于MIKE的滨海城市内涝模拟及深隧工程排涝效果评估

Waterlogging Simulation and Drainage Effect Assessment of Deep Tunnel Engineering in a Coastal City Based on MIKE

在暴雨及风暴潮等极端气象水文条件潮位影响下,快速城市化的滨海地区内涝问题日益凸显。以粤港澳大湾区深圳市西部为研究区,耦合一维河道洪水模型及管网排水模型和二维地表漫流模型,模拟极端降水和典型风暴潮条件下城市内涝淹没过程,开展内涝风险分级,评估深隧工程排涝效果。结果表明:MIKE多模型工具相结合能够较好地模拟城市内涝形成过程及淹没特征,引入概率矩阵法能够更清晰地揭示内涝风险等级之间的变化。极端气象水文条件下的滨海城市内涝淹没呈现快涨缓退特征,设计50年和100年一遇2 h极端降水下的内涝风险区面积分别为4.24、5.04 km^(2),其中1级到4级风险区范围的相对比例分别约为0.9:37.5:28.5:33.0和4.0:33.7:26.8:35.5,考虑深隧工程排涝的淹没范围分别减少了17.0%和13.4%、内涝风险区面积分别减少了28.8%和30.2%、典型易涝点的淹没持续时间缩短了60.0%~80.8%。大部分地区的内涝风险等级显著下降,深隧工程改善排涝效果明显。

Under the influence of extreme hydrometeorological conditions such as rainstorms and storm surges,the waterlogging issue in coastal areas with rapid urbanization has become increasingly prominent.Taking the western region of Shenzhen City in the Guangdong-Hong Kong-Macao Greater Bay Area as the study area,this paper couples a one-dimensional river flood model,a pipeline drainage model,and a two-dimensional overland flow model to simulate urban waterlogging processes under extreme precipitation and typical storm surge.The waterlogging risk classification is conducted and the drainage effect of deep tunnel engineering is evaluated.The results show that the formation processes and inundation characteristics of urban waterlogging can be better simulated using the combination of multiple MIKE model tools,and changes among waterlogging risk levels can be more clearly presented by the probability matrix method.Under extreme hydrometeorological conditions,the waterlogging inundation in coastal cities exhibits rapid increase and slow decrease.For designed 2-hour extreme precipitation with 50-year and 100-year return periods,the waterlogging risk range accounts for 4.24 km^(2) and 5.04 km^(2),respectively.Specifically,the relative area proportions among risk levels 1 to 4 are 0.9:37.5:28.5:33.0 and 4.0:33.7:26.8:35.5,respectively;the inundation and waterlogging risk ranges with deep tunnel engineering decrease by 17.0%and 13.4%,and by 28.8%and 30.2%respectively;the inundation duration of typical waterlogging-prone regions is shortened by 60.0%~80.8%.The significant decrease in the risk level of waterlogging in most areas demonstrates that the drainage effect of deep tunnel engineering is significantly improved.