BRB支撑刚度比对不规则钢框架的耗能减震分析

Analysis of Energy Dissipation and Damping of Irregular Steel Frame with BRB Support Stiffness Ratio

不规则结构在地震作用下必然产生扭转振动,加剧结构的破坏,而传统抗扭方法具有很大的局限性.随着耗能减震技术的发展,目前防屈曲耗能支撑(BRB)成为约束不规则结构扭转的一种有效方法.BRB在不规则结构中的布置数量和刚度分配会直接影响耗能减震的效果.通过研究不同支撑布置方案下,单个BRB与同方向总BRB的刚度比以及刚度分配对不规则钢框架的周期比、位移比、楼层顶点最大水平位移等地震响应的影响,得出BRB控制不规则结构扭转的效果.以某L形不规则钢框架为例,借助MIDAS分析软件,得到此类不规则结构BRB布置的合理刚度比和刚度分配规律,为工程实践提供参考.

Irregular structure will inevitably produce torsional vibration under the action of earthquake,which will aggravate the damage of the structure,and the traditional method of torsion resistance has great limitations.With the development of energy dissipation technology,BRB is an effective method to control the torsion of irregular structures and reduce the seismic response. The arrangement of BRB in an irregular structure and the distribution of stiffness directly affect the effect of energy dissipation. The influence of stiffness ratio of single BRB and total BRB in the same direction and stiffness distribution on the earthquake response of irregular steel frame under different support arrangements is analyzed,such as cycle ratio,displacement ratio,and maximum horizontal displacement of floor apex. The effect of BRB controlling the torsion of irregular structures was obtained. Taking an L-shaped irregular steel frame example and using MIDAS analysis software,the rational stiffness ratio and stiffness distribution rule of this kind of irregular structure on BRB arrangement are obtained,which provides reference for engineering practice.