基于GeoDam-BREACH与Graham法的溃坝生命损失估算

Estimation of life loss by dam-break flood based on GeoDam-BREACH and Graham methods

应用GeoDam-BREACH工具包模拟了超标准洪水状况下小井沟水库下游的溃坝洪水演进过程,得到水库溃坝下游淹没范围与淹没区水深分布,然后采用Graham法对溃坝导致的生命损失风险进行分析。分析结果表明,小井沟水库发生漫顶破坏时,溃坝洪水对下游产生严重影响,下游村镇有受淹风险;下游溃坝淹没区域的风险人口死亡率较高,并且随着警报时间的减小而增大,从而得出警报时间和风险人口对溃坝洪水严重性的理解程度是生命损失的重要影响因素、应当加强水库大坝的日常巡查工作和预警系统的结论。研究成果为小井沟水库的防洪调度和应急预案编制提供了有效支持,对于同类水库的防洪和安全管理亦具有参考价值。

The GeoDam-BREACH toolsets are used to simulate the process of the dam-break flood routing downstream of the Xiaojinggou reservoir under the conditions of super-standard flood. The inundated area and water depth distribution of the inundated area downstream of the dam breach are obtained. Then the analysis of the life loss risk caused by the dam breach is carried out by Graham method in this study. The analysis results show that the reservoir dam-break flood will give serious impacts on the downstream area, where the villages and towns may be at risk of flooding;and the mortality rate of population at risk in the downstream dam-break flooding area is higher and increases with the decrease of warning time. Therefore, it is concluded that the warning time and understanding of the dam-break flood severity are important factors affecting the loss of life. And the daily inspection work and early warning system of the reservoir dam should be strengthened. The research results provide effective technical support for flood control dispatch and emergency plans compilation of the Xiaojinggou reservoir, and have certain reference values for flood control and dam safety management of similar reservoirs.