南方某特大城市主城区排水防涝能力评估研究

Evaluation and Study on Capabilities of Drainage and Waterlogging Prevention in Main Town of a Large Southern City

在对南方某特大城市主城地形地貌、气象水文、排涝设施现状进行调研的基础上,采用Infoworks ICM水力模型进行排水管网一维(1D)模拟,评估不同重现期降雨情况下现状雨水管渠的排水能力。同时,基于GIS技术构建主城数字高程模型(DEM),利用1D排水管网模型耦合和二维(2D)地表漫流模型,分析确定50 a一遇24 h设计雨型工况下的内涝淹没范围形成风险分布图,并分析内涝成因,提出规划方案指导排水防涝设施的建设和管理,确保在遭遇台汛威胁时最大程度减轻灾害。

On the basis of investigate and survey the topography, weather, hydrology, and present waterlogging drainage facilities in a main town of a large southern city, the Infoworks ICM hydraulic model is used to carry out one-dimensional(1D) simulation of drainage pipeline network and to evaluate the drainage capabilities of present rainwater pipe channel under the different return periods of rainfall. At the same time,based on GIS technology, the digital elevation model(DEM) of the main town is built. The 1D drainage pipe network model coupled with two-dimensional(2D) land overflow model is used to analyze and determine the risk distribution diagram formed in the waterlogging range under the design rainfall condition of 24 hours once in 50 a, and to analyze the waterlogging cause. The planning scheme is proposed to guide the construction and management of drainage and waterlogging preventive facilities in order to ensure the maximum mitigation of disasters during the typhoon and flood periods.