全装配式自复位防屈曲支撑滞回模型及其性能试验研究

HYSTERESIS MODEL AND EXPERIMENTAL INVESTIGATION OF ASSEMBLED SELF-CENTERING BUCKLING-RESTRAINED BRACES

为减小防屈曲支撑的震后残余变形,降低结构的修复难度和成本,该文提出了一种采用组合碟簧实现复位的全装配式自复位防屈曲支撑,该新型支撑通过设置BRB系统承载力和SC系统预压力的比率,可有效控制滞回曲线的特性。文中阐述了该支撑的构造和工作原理,推导了循环加载下的理论滞回模型,并据此设计制作了3个不同组合的全装配式自复位防屈曲支撑,通过拟静力试验分析对比了残余变形和滞回耗能等特性,探讨了自复位效果和破坏模式。试验结果表明:新型全装配式自复位防屈曲支撑滞回曲线有明显的旗帜型特征,滞回性能稳定;组合碟簧自复位系统大幅减小了支撑的残余变形,复位效果明显;理论滞回模型与试验结果基本吻合,是一种十分有效的自复位减震阻尼器。

To reduce the large residual deformation of buckling-restrained braces after strong earthquake, and facilitate structural repair, an assembled self-centering buckling restrained brace with combined disc springs(SCBRB) is invented. The characteristics of the hysteretic curve can be effectively controlled by the yield force of the energy dissipation system and the pre-pressure of the self-centering system. The construction and mechanism of the novel SC-BRB were described, and the theoretical hysteretic model under cyclic loading was derived. Three different types of SC-BRBs were designed and fabricated. The residual displacement and hysteretic energy dissipation were analyzed through the quasi-static tests, and self-centering effect and failure mode were discussed.The experimental results show that the SC-BRB has flag shaped hysteretic curve and stable energy dissipation capacity. The combined disc spring self-centering system greatly reduces the residual deformation. The theoretical hysteretic model proposed in this paper agrees well with the experimental results.The novel SC-BRB is an effective self-centering damper with stable energy dissipation capacity.