两阶段耗能屈曲约束支撑体系减震效果分析

为解决高烈度区常规屈曲约束支撑减震体系地震作用较大,结构抗震性能欠佳的问题,提出同时采用普通型和早耗能型屈曲约束支撑的两阶段减震体系.结合高烈度区工程算例,以小震时结构具有相同侧向变形为原则,分别设计了常规屈曲约束支撑体系和两阶段耗能支撑体系,并采用SAP2000建立相应的数值模型.结合模态、小震下的反应谱、弹性时程和大震下的弹塑性时程对两阶段耗能屈曲约束支撑减震体系的减震效果进行了分析.结果表明,同常规屈曲约束支撑减震体系相比,两阶段耗能屈曲约束支撑减震体系的刚度降低,地震作用显著减小,塑性铰的发展得到推迟,而且屈曲约束支撑的出力显著减小,结构整体的抗震性能明显提高. 

Analysis of Damping Effect in Two-Stage Energy Dissipation Damping System of Buckling Restrained Braces

To solve the problems of the great seismic force and poor anti-seismic performance of normal energy dissipation system of buckling restrained braces in high seismic regions, it was proposed to design two-stage energy dissipation system of buckling restrained braces. With reference to one engineering example in high earthquake intensity area, the two energy dissipation systems were designed according to the principle that the lateral deformations were equal. Besides, two corresponding numerical models were established by using SAP2000.Then energy dissipation effect of two-stage energy dissipation system of buckling restrained braces was investigated through model analysis, response spectrum analysis and elastic time history analysis under the frequent earthquakes, and elastic-plastic time history analysis under the rare earthquakes. The research results indicate that compared with the normal energy dissipation system of buckling restrained braces, stiffness of two-stage energy dissipation system of buckling restrained braces is reduced, seismic force decreases significantly, and development of plastic hinges is postponed. The force of the buckling restrained braces decreases notably, anti-seismic performance is improved obviously.