基于IFMS的青衣江洪雅县城区段洪水风险分析

Flood risk analysis based on IFMS in Hongya County Qingyi River

以眉山市洪雅县城区作为研究区域,利用IFMS软件构建青衣江洪雅段一二维耦合水动力模型,研究不同重现期下的洪水对洪雅县城区的淹没影响.采用青衣江洪雅水文站的设计洪水成果及2020年青衣江8月16日到8月18日实测洪水过程率定模型参数,并结合现状堤防情况验证模型计算结果的合理性.分析计算结果表明,洪雅县城区段在遭遇20年一遇重现期以下洪水时,具有较好的防御能力;在遭遇20年一遇重现期以上洪水时,城区将遭受不同程度淹没影响,对人民群众生命财产安全威胁较大.为了进一步减少灾害损失,同时提高区域整体的防洪减灾能力,因此需要在采取工程措施保障的基础上兼顾进行非工程措施的研究.

In this paper,the urban section of Hongya County in Meishan City is taken as the study area,and a two-dimensional coupled hydrodynamic model of Hongya section in Qingyi River is constructed by using IFMS software to study the impact of floods in different return periods on urban inundation in Hongya County.The design flood results of Hongya Hydrological station of Qingyi River and the model parameters of 8.16-8.18 flood rate of Qingyi River in 2020 were used,and the rationality of the model calculation results was verified by combining with the current situation of levees.The calculation results show that Hongya County has a good defense ability when facing the flood which occurs less than once in 20 years.When the flood occurs more than once in 20 years,the urban area will be affected by different degrees of inundation,which poses a great threat to the safety of people's lives and property.It is urgent to strengthen the implementation of engineering measures and non-engineering measures to reduce the flood disaster risk.