考虑不确定性的复合灾害避难疏散风险评估模型

Risk assessment model of compound disaster evacuation considering uncertainty

为解决地震-暴雨典型复合灾害情景下避难疏散的不确定性,开展避难疏散风险评估研究。首先,基于我国避难疏散体系规划特征,提出地震暴雨复合灾害下城市避难疏散风险控制目标;其次,考虑避难疏散时间的不确定性,结合地震-暴雨复合灾害避难疏散特点,建立地震-暴雨复合灾害下城市道路通行能力快速评估模型;然后,考虑不同避难需求点风险接受程度的不确定性,提出基于城市规划用地特征的可接受风险水平系数;最后,考虑以上避难疏散过程的不确定性特征,采用优化算法计算最大覆盖应急设施选址决策模型,构建基于地震-暴雨复合灾害避难疏散风险评估模型,并以某北方城市防灾疏散责任区为实证对象,探讨多风险控制目标与多规划方案组合下的风险情况,提出该防灾疏散责任区的最小疏散风险避难场所规划方案。结果表明:该模型能更为实际地评估地震-暴雨复合灾害情景下避难疏散风险,实现不确定因素的量化分析,达到风险评估和空间规划的有效衔接。

In order to solve the uncertainty problem of evacuation under the typical complex disaster scenario of earthquake and rainstorm,the risk assessment of evacuation was studied.Firstly,based on the planning characteristics of China's evacuation system,the risk control objectives of urban evacuation under the combined disaster of earthquake and rainstorm were put forward.Then,considering the uncertainty of evacuation time and the evacuation characteristics of earthquake-rainstorm compound disaster,a rapid evaluation model of urban road capacity under earthquake-rainstorm compound disaster was established.Secondly,considering the uncertainty of risk acceptance degree of different refuge demand points,the acceptable risk level coefficient based on the characteristics of urban planning land was put forward.Finally,considering the uncertainty characteristics of the above evacuation process,the optimal algorithm was adopted to calculate the decision-making model of the location of the maximum coverage emergency facilities,and the evacuation risk assessment model based on earthquake and rainstorm combined disasters was constructed.Taking the disaster prevention and evacuation responsibility area of a northern city as an empirical object,this paper probed into the risk situation under the combination of multi-risk control objectives and multi-planning schemes,and put forward the planning scheme of the shelter with minimum evacuation risk in this disaster prevention and evacuation responsibility area.The research shows that the model can make a more practical evacuation risk assessment for earthquake-rainstorm combined disaster scenarios,realize the quantitative analysis of uncertain factors,and achieve an effective connection between risk assessment and spatial planning.