基于MikeFlood的组合情景洪水风险分析

针对模拟河道洪水淹没时,干、支流同频率暴雨组合情景不能合理反映洪水漫堤真实情景的缺陷,考虑到洪水汇流淹没过程中干、支流实际降水情况的差异,构建基于干、支流不同频率组合方案下洪水淹没情景的MikeFlood耦合水动力模型。以典型丘陵地貌地区修水为研究对象,模拟研究区域内干流以及主要支流分别发生20年、50年、100年不同频率暴雨时的24种组合情景,选取其中几种情景与干、支流发生同一种频率暴雨的典型暴雨情景进行对比。结果表明,选取的组合情景与典型情景相比,其淹没水深的分布、大小均有较大的变化,可多样性地反映洪水来临时洪水漫堤的情景,为丘陵地区的洪水风险预报和紧急避洪转移工作提供决策依据和技术支撑。

Combined scenario flood risk analysis based on MikeFlood

During the flooding o f simulated rivers, the same2frequency rainsto rm combination scenario of the ma in str eam and tributary cannot r easo nably reflect the real o verflow situat ion. In view of this defect, considering the difference of actua l pr ecipi2 tat ion conditions bet ween the main stream and tributar y during the flo oding , w e est ablished a MikeFlood coupled hydro dy namic model based on floo ding scenario s of different fr equency combinatio ns of t he main str eam and tributar y. I n this paper, the typical hilly landform area, Xiushui, was taken as the research object. We simulated the 24 combinations in w hich the main stream and the main tributaries r espectively had 202, 502 and 1002year r ainstorms. We compar ed several scenario s w ith the ty pical st orm scenario s in which the ma in str eam and tribut aries had rainsto rms o f the same frequency. The compariso n results show ed t hat the selected combination scenarios pr esented much different distribution and size o f submer ged dept h than the t ypical scenarios. They can div ersely reflect the o verflow situation in the flood, pro viding