溃坝风险区避迁能力评估研究

Flood disaster evacuation is the major measure for the population at risk to cope with dam-break. GIS technology makes the differences of spatial distribution of natural and social factors in disaster area clear. Emergency evacuation simulation modeling shows the description on the process of the population at risk moving over time, which enables to combine the distribution of time-space characteristics of these factors with traditional index system assessment method, putting forward a new model on evaluating the evacuation capability in risk area of dam-break. By taking the risk area of Beishan Reservoir in Jiangsu Province as the research area, this project carries out the evacuation capability evaluation in coupling risk area of dam-break based on index system and emergency transfer simulation. The main research contents and processes are: extract natural and social factors influencing the evacuation ability in risk area of dam-break; establish comprehensive evaluation model of two-dimensional index system based on the disaster risk of dam-break and disaster-resistance capability and get the initial value of capability evaluation on evacuation in dam-break disaster; correct the initial value by simulating the emergency transfer process of the population in risk area and use the corrected value in the next evaluation on two-dimensional index system of disaster-resistance; thus, the circulation of “handling - adjustment” can realize the dynamic evaluation on the evacuation capability in dam-break process. The research result is of important theoretical and practical significance in understanding dam-break risk and the evolution process of evacuation capability, putting forward scientific and reasonable dynamic evaluation on evacuation capability and improving the management level of reservoir dam in China.

避难迁安是风险人口应对溃坝灾害的主要手段。GIS技术使风险区自然和社会要素的空间分布差异性得以体现，应急疏散仿真建模实现了风险人口随时间流动的过程描述，将这些要素的时空特性分布与传统的指标体系评估方法相结合，提出溃坝风险区避迁能力评估的新模式。以江苏省北山水库溃坝风险区为研究区域，开展基于指标体系和应急转移模拟的耦合溃坝风险区避迁能力评估。首先，提取影响溃坝风险区避迁能力的自然和社会要素，建立基于溃坝灾害风险和抗御灾害能力的二维指标体系综合评估模型，获取溃坝避迁能力评估初值；通过模拟风险区人口应急转移过程对溃坝避迁能力评估初值进行修正，修正结果用于下一时刻的避迁能力二维综合评估，实现“处置-调整”型溃坝全过程避迁能力动态评估。研究成果对于认识溃坝风险和避迁能力的演变过程，提出科学合理的应急处置决策，提高我国水库大坝管理水平具有重要的理论和现实意义。

本研究选择安徽省港口湾水库副坝溃决风险区为项目示范区，开展了溃坝风险区洪水风险要素、交通分布等自然要素和风险人口特征、应急预警处置等社会要素耦合作用下的溃坝风险区避迁能力评估问题。在溃坝洪水数值模拟和洪水风险图绘制的基础上，分析并提取了影响溃坝风险区避迁能力的自然和社会要素；建立了基于溃坝灾害风险和抗御灾害能力的二维指标体系综合评估模型，获取了溃坝避迁能力评估初值；通过模拟风险区人口应急转移过程对溃坝避迁能力评估初值进行修正，并绘制避迁能力动态分布图，实现了“处置-调整”。研究成果对于认识溃坝风险和避迁能力的演变过程，提出科学合理的应急处置决策，提高我国水库大坝管理水平具有重要的理论和现实意义。