FRC框架结构地震风险评估的简化方法  

A SIMPLIFIED METHOD FOR EVALUATING THE SEISMIC RISK OF FRC FRAME STRUCTURES

作　　者：黄超[1] 梁兴文[1] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《工程力学》2017年第7期117-125,共9页Engineering Mechanics

基　　金：国家自然科学基金项目(51278402;51078305)

摘　　要：对结构地震风险进行精细的量化分析成为在直接财产损失、居住中断时间、死亡人数评估中必不可少的部分。该文首先用增量动力分析(IDA)法对纤维增强混凝土(FRC)框架结构进行动力时程分析,获得其IDA曲线,据此确定结构的地震易损性曲线,并由此考虑知识不确定性,确定考虑知识不确定性的易损性曲线;按考虑知识不确定性的易损性曲线与地震危险性曲线相结合,进行风险评估;然后基于Laura Eads等提出的评估地震风险的简化方法来进行风险评估。分别对按我国规范设计的8层FRC框架结构和钢筋混凝土(RC)框架结构进行分析。结果表明:采用简化方法得到的FRC框架和RC框架结构的倒塌风险均偏大,误差分别为5.7%和8.0%,对于结构风险评估是可行和偏于保守的。Seismic risk quantification has become necessary as it is a required component in estimating direct monetary losses, downtime, and fatalities. Firstly, dynamic history analysis was conducted on a Fiber Reinforced Concrete （FRC） structure by means of incremental dynamic analysis （IDA） method in the paper, and an IDA curve was attained. On the basis of this IDA curve, the seismic fragility curve was derived. According to the seismic fragility curve and the epistemic uncertainty, the seismic fragility curve considering epistemic uncertainty was determined. Combining the seismic fragility curve considering epistemic uncertainty with the seismic hazard curve, the seismic risk was then evaluated. Then, an evaluation procedure of seismic risk of structures is presented in the paper, which is based on the simplified methodology proposed by Laura Eads. An 8-story FRC framed structure and an 8-story reinforced concrete （RC） framed structure which were designed according to the current Chinese codes were analyzed. The results show that the seismic risk with the simplified methodology is higher than that with the existing methodology for both the FRC framed structure and the RC framed structure, the errors were 5.7% and 8.0% respectively, and it is feasible and conservative to use the simplified methodology to evaluate the seismic risk.

关 键 词：地震风险 增量动力分析 纤维增强混凝土 地震易损性 知识不确定性 

分 类 号：TU311.2[建筑科学—结构工程] TU375.4