考虑多次地震恢复的地震灾害风险评估模型构建

Constructing earthquake disaster risk assessment model based on recovery differences of different damage states of multi-earthquake

概率地震灾害风险评估中存在地震危险性取值和多次地震对地震灾害损失风险评估影响的两个问题,我国概率地震危险性分析(probabilistic seismic hazard analysis,PSHA)框架下,研究了地震动超越概率、极值概率和发生概率三种地震危险性表达之间的区别与联系,建立了这三种地震危险性表达之间的转化关系,并给出了采用地震动超越概率或极值概率计算发生概率的简化公式。根据承灾体震后恢复重建实际情况,对现有地震灾害风险评估模型假定进行了修正,推导出了仅考虑承灾体一次破坏的“首超”地震灾害损失风险评估表达式,并结合基于地震场地烈度频度的地震期望损失估计方法,提出了考虑多次地震不同破坏状态恢复差异的地震灾害损失风险评估模型,为地震灾害风险评估提供参考。

There are two problems in probabilistic seismic hazard risk assessment of seismic hazard magnitude value and effects of multi-earthquake on seismic hazard loss risk assessment.Here,in framework of probabilistic seismic hazard analysis(PSHA)in China,differences and connections among 3 seismic hazard expressions of seismic motion exceedance probability,extreme value probability and occurrence probability were studied.Conversion relations among these 3 seismic hazard expressions were established,and a simplified formula to calculate seismic motion occurrence probability with seismic motion exceedance probability or extreme value probability was given.According to the actual situation of post-earthquake recovery and reconstruction of disaster-bearing body,the existing earthquake disaster risk assessment model assumption was modified,the expression for the“first exceeding”earthquake disaster loss risk assessment considering only one damage of disaster-bearing body was derived,and combined with the earthquake expected loss estimation method based on seismic site intensity and frequency,the earthquake disaster loss risk assessment model considering recovery differences of different damage states of multi-earthquake was proposed to provide a reference for earthquake disaster risk assessment.