考虑场地效应地震动确定方法对结构地震易损性的影响研究  

INFLUENCE OF PROBABILISTIC SEISMIC VULNERABILITY ANALYSIS ON GROUND MOTION DETERMINATION METHOD WITH CONSIDERING SITE EFFECT

作　　者：高永武 王东明 陈敬一 GAO Yong-wu;WANG Dong-ming;CHEN Jing-yi(China Earthquake Disaster Prevention Centre,Beijing 100029,China)

机构地区：[1]中国地震灾害防御中心,北京100029

出　　处：《工程力学》2025年第4期139-149,共11页Engineering Mechanics

基　　金：国家重点研发计划项目(2022YFC3006400,2022YFC3006403);中国地震局地震科技星火计划项目(XH23055A)。

摘　　要：针对结构地震易损性分析中地震动选取考虑场地效应认知不足的问题,该文给出了一种采用基岩地震动调幅结合土层反应分析充分考虑场地效应的地震动确定方法。基于该方法设计了结构地震易损性分析的基准输入地震动,同时构建了“不考虑”、不完全考虑、现有方法考虑场地效应的3种地震动输入作为对照组。采用3种层间力-位移恢复力关系的集中质量简化模型,开展了不同地震动输入工况下结构地震易损性分析,进行了3种结构对照组与基准组的地震易损性曲线4个极限状态中位值mRR,D以及对数标准差βRR,D的相对差值比对比分析。研究表明不同程度考虑场地效应得到的结构地震易损性结果存在差异,且差异随结构地震易损性极限状态的增强而变大。在此基础上,利用地震易损性函数区间估计模型,给出了不同程度考虑场地效应认知不确定性系数值,为地震易损性分析中考虑场地效应认知不确定性系数修正提供参考。Based on the lack of epistemic of site effects when selecting ground motion in structural seismic vulnerability analysis,a ground motion determination method is proposed with a view towards considering the site effect.The method combines the amplitude modulation of bedrock ground motions and earthquake response analysis of soil layers.The standard input ground motion for seismic vulnerability analysis of structures is established upon this method.Meanwhile,three groups of ground motion input with'unconsidered',incomplete consideration,and existing methods considering site effects are designed as comparisons.Three kinds of lumped mass simplified models of interlayer force-displacement restoring force relationship were used to analyze structural seismic vulnerability under different ground motion input conditions.Obtained is a comparative analysis for the relative difference ratios of the median mRR,D and logarithmic standard deviation β RR,D of the four limit states of the seismic fragility curves of the control group and the standard group considering the three structures.The research shows that the seismic vulnerability of structures with different site effect is different,and that the difference tends to increase with the increase of the limit state of seismic vulnerability.According to the analysis results,the epistemic uncertainty coefficient values considering the site effect in different degrees are developed by the interval estimation model of seismic vulnerability function.The method can provide a reference for considering site effect epistemic uncertainty coefficient correction in seismic vulnerability analysis.

关 键 词：概率地震易损性分析 基岩地震动 场地效应 地震动选取 认知不确定系数 

分 类 号：TU312[建筑科学—结构工程]