借鉴美国规范ASCE/SEI7-05和FEMA368关于三维分析的选波思路,并与我国二维分析中的双频段法相结合,提出了根据地震波两水平分量反应谱的SRSS谱与目标设计反应谱进行拟合的SRSS法和双周期法.以3个空间框架为例,分别以多遇地震下的最大弹性基底剪力、罕遇地震下的最大弹塑性顶点位移和最大弹塑性层间位移角为结构响应指标,对比分析了双频段法、SRSS法和双周期法对双向水平地震波的选择控制效果.结果表明,双周期法得到的最大弹性基底剪力离散性最小,SRSS法和双周期法得到的最大弹塑性顶点位移和最大弹塑性层间位移角的离散性均小于双频段法,双周期法具有对几种地震响应指标更全面、更好的控制效果.

Proposed in this paper are two methods to select the input waves under seismic action,one is SRSS method and the other is dual period method.The two methods,fitting the target design response spectrum with the SRSS spectrum in the response spectra of two horizontal earthquake components,refer the notion of selecting input earthquake waves for three-dimension analysis in American codes ASCE/SEI 7-05 and FEMA 368,and integrate with the dual frequency interval method of two-dimension analysis used in China.Then,by taking three spatial frames as examples,and by using the maximum elastic base shear under frequent earthquake,as well as the maximum elasto-plastic top displacement and elasto-plastic inter-story drift angle under rare earthquake as the structural response indicators,the selecting and controlling effects of the two proposed methods are compared and analyzed.The results show that the deviation of the maximum elastic base shear obtained by the dual period method is lowest,that the deviations of the maximum elasto-plastic top displacement and the maximum elasto-plastic inter-story drift angle obtained by the SRSS method and the dual period method are lower than those obtained by the dual frequency interval method,and that the dual period method controls the structural response indicators more comprehensively and effectively.