摘要
论述人字支撑架横梁设计时不平衡力取较小值时的支撑架性能和带来的后果,分析发现支撑架的性能决定于横梁能够承受的不平衡力。基于4个系列算例,介绍了框架和人字支撑架按照抗侧承载力比值为1∶1和1∶3组成的双重抗侧力结构的侧向力-侧移角曲线,其中人字支撑架的横梁能够承担GB 50011—2010《建筑抗震设计规范》规定的不平衡力的30%和100%。因为压撑、拉撑和框架达到各自极限状态的侧移角是依次增加的,压撑先屈曲,然后承载力退化,但是框架的承载力在不断发挥,补偿了压撑承载力的退化。总的侧向力发生或不发生退化取决于横梁能够承担的不平衡力和框架与支撑的承载力比值。为此,拟合了总抗侧力退化不大于20%时框架抗侧承载力占比与支撑架横梁应该承担的不平衡力的比例关系。
The static behavior of chevron brace when its beam is designed by a smaller unbalanced force is reviewed and it is revealed that the post-buckling behavior is fully dependent on the capacity of beam carrying unbalanced force.Lateral force-drift angle curves of dual systems composed of frame and chevron brace with their lateral capacity ratios of 1∶1 and 1∶3 are introduced,the capacity of the beam in chevron brace can carry 1.0 and 0.3 times the codified unbalanced force,respectively,totally 4 series of examples.Because the drift angles at brace buckling,tension yielding and frame lateral mechanism increase in order,brace buckling occurs first and then its capacity deteriorates,but the capacity of the frame develops and compensates the decrease of the compressive brace force,the total lateral capacity of the system after brace buckling depends on both the frame/brace capacity ratio and the capacity of the beam in chevron brace carrying unbalance force in chevron brace.Under the demand of assuring the total deteriorating percentage less than 20%,a relation between the frame/brace capacity ratio and the unbalance force ratio ratio is proposed.
作者
童根树
Genshu Tong(Institute of High Performance Structures,Zhejiang University,Hangzhou 310058,China)
出处
《钢结构（中英文）》
2023年第12期54-57,共4页
Steel Construction（Chinese & English）
关键词
双重结构体系
框架
人字撑
不平衡力
dual structural system
frame
chevron brace
unbalance force
