城市构筑物暴雨内涝分层模拟技术及应用

气候变化和城市快速发展，导致我国城市洪涝问题日益突出。城市洪涝模拟是当前城市洪涝灾害风险管理领域研究热点，但国内外依然缺乏针对城市多层构筑物的精细模拟技术和方法。城市立交桥，是一种典型的城市多层构筑物，极易遭受洪涝灾害，并对城市交通造成严重影响。以城市立交桥为代表，在现有全分布式城市暴雨内涝模型基础上，结合城市立交桥的特点，提出一种分层模拟技术，并从网格分层构建、分层产汇流计算、地表与管网分层耦合和上层网格排水等方面详细阐述了分层模拟技术。将该分层模拟技术应用于深圳市罗芳立交桥2018年“8.29”暴雨积水过程模拟，与单层模拟方法相比，多层模拟结果更接近上报积水信息。研究表明，分层模拟技术更能准确表达城市复杂多层建筑物的实际暴雨内涝过程。

A stratified modeling approach to flooding at urban infrastructures

Climate change and rapid development have led to an increasing number of flooding problems in urban China.Flood simulation is a leading research topic in urban flood risk management.However, there is still a lack of effective approaches to simulate flooding in multi-layer infrastructures because of their complexity.As a typical type of multi-layer infrastructure commonly seen in large cities, overpasses are usually susceptible to being affected by floods, which have a serious impact on the surrounding traffic.Given these characteristics of city overpasses, a stratified modelling approach to flooding at urban multi-layer infrastructures based on a distributed urban flood model is proposed.Details about the approach are discussed, such as the construction of a multi-layer grid, rainfall runoff generation on the multi-layer grid, the coupling between the multi-layer grid and drainage network, and water collection on the upper levels.This approach is applied to the simulation of the flooding that happened at Luofang overpass in Shenzhen during the rainstorm on August 29, 2018.Compared to the single-layer simulation approach, the proposed stratified approach gives a closer simulation to the reported flooding.This study shows that the stratified approach can better display the real flooding process at complicated multi-layer infrastructures in urban areas.