在役钢结构基于损伤模型的地震易损性分析

Seismic vulnerability analysis of steel structure in service based on damage model

基于已有钢材力学性能及钢材厚度锈蚀规律,对4个不同服役时间(0年、15年、30年、45年)的钢框架结构以峰值加速度(PGA)作为地震动强度指标,以结构整体损伤作为地震需求指标,对结构进行增量动力时程分析(IDA),对分析结果进行对数线性拟合,分别建立离散的地震易损性曲线,同时建立连续的地震易损性曲线。以一个15层3跨钢框架为例,建立有限元模型并对结构进行IDA分析,同时建立不同服役时间地震易损性曲线。研究成果可为结构的全寿命设计、既有结构的运营以及地震风险评估等提供理论依据。

Based on the current mechanical properties of steel and steel thickness corrosion law,incremental dynamic analysis( IDA) was carried out on four steel frame structures with different service times( 0 years,15 years,30 years,45years) with PGA as the earthquake intensity index and the structure overall damage as the seismic demand index. Log linear fitting was conducted on the analytical results to establish discrete seismic vulnerability curves respectively and establish continuous seismic vulnerability curves according to the proposed method. Taking a 15-story 3-span steel frame as an example,the finite element model was established and IDA analysis of the structure was conducted. At the same time,seismic vulnerability curves of different service times were established according to the proposed method. The research results can provide a theoretical basis for the life cycle design of the structure,existing structure operation and seismic risk assessment.