基于博弈论组合权重的城市洪涝风险评估

Urban flood risk assessment based on game theory-based combination weighting method

摘要

【目的】洪涝风险评估在地区防灾减灾体系建设中发挥重要作用，但目前研究多集中于县域、市域等大尺度的地区，对小尺度城区少有涉及。为有效评估城市地区洪涝风险，提升风险评估的精细化水平，【方法】借助MIKEFLOOD水动力模型模拟技术并引入博弈论的组合赋权模型，建立一种适用于城市地区的洪涝风险评估方法。以德兴市城区为例，采集德兴市2022年6月18日12∶00至6月23日12∶00降雨流量过程、无人机航拍德兴市城区DEM高程图、实测河道断面等多源数据，构建德兴市城区MIKEFLOOD水动力模型进行洪水模拟，验证模型合理性后依据洪水模拟结果选取最大淹没水深、最大淹没历时、最大淹没面积和最大淹没流速作为危险性指标，结合研究区环境脆弱性、承灾体暴露性指标构建城区洪涝灾害风险评估体系。对于评估体系中的指标赋权问题，创新性地引入博弈论思想，有效融合主观经验与客观数据信息，克服单一赋权法的局限性，系统分析德兴市城区洪涝灾害风险指标，有效评估德兴市城区洪涝灾害风险。【结果】结果显示：德兴市城区共有22个社区，其中13社区存在高风险，其中新营一村(高风险区面积0.115 km²)、上洲社区(0.067 km²)、天门山社区(0.034 km²)、岁寒山社区(0.024 km²)、洎水社区(0.020 km²)、水绿桥社区(0.019 km²)、银山社区(0.013 km²)、南门社区(0.012 km²)、肯堂山社区(0.011 km²)、银泉社区(0.011 km²)、吴园社区(0.009 km²)、胜利亭社区(0.004 km²)和武安路社区(0.002 km²)。【结论】结果表明：MIKEFLOOD模型在城区洪水模拟中表现出良好的准确性与可靠性，很好地揭示了城区的洪水空间分布特征。无人机航拍的高精度DEM高程图在城区洪涝风险评估中是至关重要的，不仅为MIKEFLOOD模型提供精准地形信息，也为环境脆弱性分析提供可靠依据，对于小尺度的城区务必采用无人机航拍高程。熵权法与层次分析法分别计算所得的权重存在较大差异，仅凭主观判断难以有效权衡，而基于博弈论的组合赋权方法以数学原理为基础，综合两类权重结果，从而得到更为科学合理的权重分配，对综合评价中的权重确定具有重要参考价值。德兴市城区的洪涝风险评估结果对未来开展洪涝灾害精准防治与风险分级防控提供了可靠的决策依据，同时也可为类似地区的防洪减灾工作提供理论方法参考。

Abstract

[Objective] Flood risk assessment is crucial for developing regional disaster prevention and mitigation systems. However, current research focuses mainly on large-scale areas such as counties and cities, with limited attention to small-scale urban districts. The aim is to effectively assess urban flood risk and enhance the refinement level of risk assessment.[Methods] A flood risk assessment method suitable for urban areas was established by integrating the MIKEFLOOD hydrodynamic modeling technique with a game theory-based combination weighting model. Taking the urban area of Dexing City as an example, multi-source data were collected, including rainfall and runoff process from 12:00 on June 18 to 12:00 on June 23, 2022, a high-resolution digital elevation model(DEM) of the urban area obtained from UAV aerial photography, and measured river cross-sections. A MIKEFLOOD hydrodynamic model for the Dexing urban area was then constructed for flood simulation. After validating the model, four hazard indicators were selected based on the flood simulation result: maximum inundation depth, maximum inundation duration, maximum inundation area, and maximum inundation flow velocity. These were combined with indicators of environmental vulnerability and disaster-bearing body exposure to establish an urban flood disaster risk assessment system. To address the indicator weighting problem within the assessment system, game theory was innovatively introduced to effectively integrate subjective experience with objective data information, thereby overcoming the limitations of single weighting method. This enabled systematic analysis of the flood disaster risk indicators and effective assessment of flood disaster risk in the Dexing urban area.[Results] The result showed that there were 22 communities in the Dexing urban area, among which 13 were classified as high-risk, including Xinyingyi Village(high-risk area of 0.115 km²), Shangzhou Community(0.067 km²), Tianmenshan Community(0.034 km²), Suihanshan Community(0.024 km²), Jishui Community(0.020 km²), Shuilvqiao Community(0.019 km²), Yinshan Community(0.013 km²), Nanmen Community(0.012 km²), Kentangshan Community(0.011 km²), Yinquan Community(0.011 km²), Wuyuan Community(0.009 km²), Shengliting Community(0.004 km²), and Wuanlu Community(0.002 km²).[Conclusion] The result indicate that the MIKEFLOOD model demonstrates good accuracy and reliability in urban flood simulation, effectively revealing the spatial distribution characteristics of flood in urban areas. The high-precision DEM obtained via UAV aerial photography is crucial for urban flood risk assessment, as it not only provides accurate topographic information for the MIKEFLOOD model but also offers a reliable basis for environmental vulnerability analysis. For small-scale urban areas, UAV aerial surveying should be used to obtain elevation data. Significant differences are observed between the weights calculated by the entropy weight method and the analytic hierarchy process, making it difficult to achieve effective balance through subjective judgment alone. In contrast, the game theory-based combination weighting method, based on mathematical principles, integrates the result of these two weighting method to achieve a more scientific and rational weight allocation, providing important reference value for weight determination in comprehensive assessment. The flood risk assessment result for the Dexing urban area provide a reliable decision-making basis for the precise prevention of flood disasters and for risk classification and control in the future. Additionally, they can serve as a theoretical and method ological reference for flood prevention and mitigation efforts in similar regions.

关键词

水动力模型 / 洪涝灾害 / 博弈论组合赋权 / 城市洪涝风险评估 / MIKEFLOOD / 城市内涝 / 风险分级防控 / 降水

Key words

hydrodynamic model / flood disaster / game theory-based combination weighting / urban flood risk assessment / MIKEFLOOD / urban flooding / risk classification and prevention / precipitation

基金资助

江西省科技厅重点研发计划“江西省典型区域洪涝灾害预报预警系统关键技术研发”(20243BBH81006)

国家重点研发计划项目“山谷型尾矿库受特小流域洪水威胁的风险预测技术”(2023YFC3012202)