基于MPA的单向偏心结构性态评估方法

Performance evaluation procedure based on MPA method for uni-directional eccentric structures

为研究水平单向偏心结构的性态评估问题,在对偏心结构模态分析的基础上,建立了等效二自由度(EDDOF)简化模型,并用其计算包含平扭耦联效应的单向非对称结构地震反应.通过弹性反应分析,验证了EDDOF模型的正确性.将MPA方法用于单向偏心结构,提出了基于MPA的单向偏心结构性态评估方法.通过一个偏心钢框架结构算例验证了方法的正确性.结果表明:简化模型结合MPA方法,可以精确地描述单向非对称结构的弹性地震反应,对非弹性反应的计算精度也很好,且计算效率较高.

To estimate the performance of uni - directional gree of freedom （EDDOF） model, which is based on the eccentric structures, a modal equivalent dual -demodal information of the structures, is constructed for calculating the coupled lateral - rotational responses. The EDDOF model is verified through elastic response analysis. The modal pushover analysis （MPA） method is applied to asymmetric structures, and an MPA based performance evaluation method for eccentric buildings is proposed. A 4 - story steel frame building is used to verify the proposed method. The results show that the simplified EDDOF system with MPA can estimate the elastic response of structures accurately. Furthermore, the proposed method is reliable and effective for evaluating the nonlinear seismic performance of asymmetric structures with favorable precision.