含屈曲约束耗能件的钢框架节点抗震性能有限元分析

Finite element analyses on seismic performance of steel frame joints with buckling-restrained energy dissipators

传统的钢框架节点地震时在焊缝位置易产生脆性破坏,且在震后难以修复。为此,提出了一种含可更换屈曲约束耗能件的钢框架节点,用于提升节点的抗震性能和功能可恢复性。采用有限元软件ABAQUS对该节点的抗震性能进行数值模拟,分析了约束板间隙、约束板厚度、核心板削弱程度参数对该节点滞回性能的影响。结果表明:本文提出的节点具有稳定饱满的滞回性能;屈曲约束耗能件中的核心板率先屈服耗能,控制主体梁柱在大位移角下仍保持弹性。参数化分析结果表明:当约束板间隙较大时,节点滞回曲线饱满程度降低;约束板的厚度在设计时建议大于核心板厚度;核心板削弱程度影响节点承载能力和损伤控制效果。

The traditional steel frame joints are vulnerable to a brittle failure at the positions of weld during earthquakes,and it is hard to repair after the earthquakes.Therefore,a steel frame joint with a buckling-restrained energy dissipator(BRED)is proposed in this paper to improve the seismic and resilience performance.The finite element software ABAQUS is used to simulate and analyze the seismic performance.The effects of the gap of restraint plate,the thickness of restraint plate,and the weakening degree of core plate on the hysteretic performance of the joint are discussed.The results show that the BRED proposed in this paper performs a stable and full seismic performance;the core plates in the BRED yield first and dissipate the energy to control that the main beam and column still remain elastic.The results of parametric analyses show that the full degree of the hysteretic curve is reduced with the increase of the gap between restraint plates and core plates.It is recommended that the thickness of the restraint plate is larger than that of the core plate.The weakening degree of the core plate affects the bearing capacity and the damage control result.