针对罕遇地震荷载作用下的屈曲约束支撑框架结构，从附加有效阻尼比的角度出发，系统的分析了罕遇地震时，屈曲约束支撑框架结构体系弹塑性位移的简化求解方法，并将此简化求解方法的计算结果与十条地震波的弹塑性时程分析结果平均值进行对比，结果表明，本文所用的简化算法准确有效。

Basing on the buckling-restrained braced frame under severe earthquakes, and from the point of additional effective damping ratio and energy principle, a simplified calculation method to solving elastic-plastic displacement of the buckling-restrained braced frame under severe earthquakes has been systematically analyzed. In this paper, the detailed calculating method and steps are presented. Moreover, the comparing analysis between the calculation result of simplified calculation method and the mean of the results of ten seismic waves’ elastoplastic time-history analysis has been carried out. The outcome shows that the simplified calculation method is an exact and valid method.