考虑洪涝灾害风险的县域应急避难场所选址模型

Location selection model of emergency shelter considering risk of flood disaster in county

为提升应急避难场所在灾害管理过程中的服务水平,从洪涝灾害的视角出发,选取致灾因子危险性、孕灾环境敏感性、承载体脆弱性、防灾减灾能力4个指标,采用层次分析法(AHP)-熵权法模型,识别出洪涝灾害风险的空间分布,并将其风险值作为权重引入最小化未覆盖风险,同时,结合最小化加权疏散距离、最小化可达性差异,从公平性、效率性、均衡性视角,构建多目标避难场所选址模型;采用改进的非支配排序遗传算法Ⅱ(NSGA-Ⅱ)求解模型,并以莆田市仙游县现有避难场所布局为例,验证模型。结果表明:对比现有的避难场所布局,优化后的布局方案中总疏散距离、未覆盖风险值及可达性差异性系数分别平均降低35.90%、61.47%、33.62%。

In order to improve the service level of emergency refuge in the process of disaster management,from the perspective of flood disaster,four indexes were selected:risk of disaster causing factor,sensitivity of disaster-bearing environment,vulnerability of carrier and ability of disaster prevention and reduction.The spatial distribution of flood risk was identified through the AHP-entropy weight method model.Its risk value was introduced as a weight to minimize uncovered risk.Combined with minimizing the weighted evacuation distance and minimizing the accessibility difference,a multi-target shelter location selection model was constructed from the perspective of fairness,efficiency and balance.The improved NSGA-II algorithm was used to solve the model,and the existing shelter layout in Xianyou County,Putian City was used as an example for model verification.The results show that compared with the existing shelter layout,the total evacuation distance,uncovered risk value and accessibility difference coefficient in the optimized layout scheme are reduced by 35.90%,61.47%and 33.62%respectively.