基于增量动力分析的钢框架结构抗震性能评估

为了预测结构的抗震能力，以分别代表低层、中层及高层结构的3层、9层、20层钢框架为例，采用增量动力分析方法对3个结构模型进行了近断层地震作用下不同强度指标的地震性能评估．基于增量动力分析，从概率的角度得到了结构在不同强度指标下的地震危险性曲线、年平均超越概率及重现周期．通过对比分析发现不同层数的结构模型选取不同的强度指标进行性能评估的有效性不同：3个结构模型均适合采用Sa作为地震动强度指标；3层钢框架不适合采用aPGA作为强度指标，9层钢框架较适合采用aPGA作为强度指标，而20层钢框架选取aPGA作为强度指标的有效性尚不确定．

Seismic performance evaluation of steel moment-resisting frames using incremental dynamic analysis

Taking a 3-storeyed steel moment-resisting frame,a 9-storeyed one and a 20-storeyed one respectively as an example,an incremental dynamic analysis(IDA) was performed on the three models under near-fault ground motions to do seismic performance evaluation with different intensity measures to predict the seismic capacity of structures.Based on IDA,through the perspective of probability,seismic hazard curves,mean annual exceeding probabilities and return periods were gotten under different intensity measures.Through comparative analysis,it shows that,for models with different storeys,the effectiveness of the choosing of intensity measures to do seismic performance evaluation is different.These three structural models are all suitable for using Sa as intensity measures.For 3-storey steel frame,it is not suitable for using aPGA as intensity measure.For 9-storey steel frame,it is comparatively suitable for using aPGA as intensity measure.However,for 20-storey steel frame,the effectiveness of using aPGA as intensity measure needs further investigations.