火电厂钢框排架-消能支撑结构低周往复加载试验

Experimental Study of Steel Frame-bent Structure With Energy Dissipation Braces of Thermal Power Plant Under Cyclic Loading

为研究钢框排架-消能支撑结构的抗震性能,以某钢结构火电厂主厂房为原型并采用防屈曲支撑作为消能装置,设计了1榀5层的钢框排架-消能支撑结构试件.通过低周往复加载试验,分析其破坏机制、滞回性能、刚度退化规律、层间变形及防屈曲支撑耗能能力.试验结果表明:钢框排架-消能支撑结构具有较高的抗侧刚度及承载能力.模型试件滞回曲线呈饱满的梭形,等效黏滞阻尼系数达0.262,位移延性系数超过3.53,表现出良好的耗能及延性性能.试验过程中,防屈曲支撑可在较小加载位移时先于主体梁柱进入屈服且塑性耗能特征明显,增加了结构阻尼且耗能稳定,有效提高了结构抗震性能.

To investigate the seismic behavior of steel frame-bent structure with energy dissipation braces, single specimen of five-story steel structure with BRB （ buckling restrained brace,B R B ） selected from a thermal power plant main building was designed. Failure mechanism, hysteretic c a p a c i ty ,stiffness degradation law,inter-story displacement and energy dissipation capacity of BRBs were analyzed through low cyclic loading tests. The results show that steel frame-bent structure with energy dissipation braces has good lateral stiffness and bearing capacity. The specimen shows good ductility and energy dissipation capacity,being of plump spindle hysteretic loops,and the equivalent viscous damping coefficient reaches 0.262,and the coefficient of displacement ductility exceeds 3.53. The BRB starts to yield at smaller loading displacement before beam-column yields and the energy dissipation characteristic is obvious, so the viscous damping of structure is increased, resulting in an improved seismic performance.