考虑材料时变特性的钢–混组合结构地震易损性分析

Seismic Vulnerability Analysis of Steel-Concrete Composite Structures Considering Time-Dependent Damage of Materials

面向复杂高层型钢–混凝土组合结构,考虑混凝土材料在服役期内的劣化过程,提出了一种考虑材料时变特性的地震易损性分析方法。基于增量动力分析(IDA)获得结构在不同服役年限时遭遇地震的动响应,并结合地震损伤模型和理论地震易损性分析方法,获取结构的地震易损性曲线。以一典型复杂高层型钢–混凝土组合结构为算例,选取15条地震波,基于MIDAS GEN软件进行IDA分析,继而绘制出设计及时变易损性曲线,评估结构在服役期间内的抗震性能。结果表明:考虑材料的性能时变特征,可以更为准确地分析和评估组合结构的抗震性能。地震易损性曲线呈现出一定的时变特性,与不考虑材料时变性能的设计曲线存在差异。鉴于此类结构的重要地位,其地震易损性随材料时变特性的变化值得关注。本文提出的考虑材料时变特性的组合结构地震易损性分析方法能直观地反映结构在不同服役期内抗震性能的差异,为预测预防地震灾害提供一定的依据。

Aiming at the complex high-rise steel-concrete composite structures and considering the deterio-ration process of concrete materials during service period,a seismic vulnerability analysis method considering the time-varying characteristics of materials is proposed.Based on incremental dynamic analysis(IDA),the dynamic response of the structure subjected to earthquake during different service years is obtained,and the seismic vulnerability curve of the structure is obtained by combining the seismic damage model and theoretical seismic vulnerability analysis method.Taking a typical complex high-rise steel-concrete composite structure as an example,15 seismic waves are selected and IDA analysis is conducted based on MIDAS GEN software.Then the designed vulnerability curves and time-varying vulnerability curves were drawn to evaluate the seismic performance of the structure during service periods.The results show that considering the time-varying characteristics of materials,the seismic behavior of composite structures can be analyzed and evaluated more accurately.The seismic vulnerability curve shows a certain time-varying characteristic,which is different from the designed curve which does not consider the time-varying performance of the material.In view of the important position of such structures,the change of the seismic vulnerability with the time-varying properties of materials is worth noting.The seismic vulnerability analysis method for composite structures considering time-varying characteristics proposed in this paper can directly reflect the difference in seismic performance of structures during different service periods and provide a basis for predicting and preventing earthquake disaster.