防屈曲支撑-混凝土框排架结构抗震试验及设计建议

Seismic Experiment and Design Suggestion for BRB-Concrete Frame Bent Structure

为了研究防屈曲支撑-混凝土框排架结构的抗震性能,以某双跨框架和排架组成的钢筋混凝土火电厂主厂房为原型,设计制作了一榀四层防屈曲支撑-钢筋混凝土框排架结构试件,通过水平静力反复加载试验,研究其裂缝开展及损伤机制、滞回曲线、刚度退化规律、结构变形能力、防屈曲支撑耗能能力等.研究结果表明:结构水平力-顶点侧移滞回曲线饱满,防屈曲支撑与主体结构协同工作性能好,可实现这种结构体系的消能减震耗能机制,实测应变和应力应变曲线得到的防屈曲支撑轴力-轴向位移曲线显示其耗能效果显著,增加结构阻尼比.针对除氧间及煤仓间底部2层的抗剪构造设计、煤仓间刚性层(由钢梁、钢支撑及混凝土梁组成)的薄弱部位设计、BRB支撑形式及单榀结构试验模型设计试验等提出了建议.

In order to study the seismic performance of buckling-restrained brace(BRB)-reinforced concrete frame bent(RCFB)structure,a four-story BRB-RCFB structure specimen was designed and manufactured,based on the prototype of the main workshop of a concrete reinforced thermal power plant consisting of a double-span frame and bent.The crack development and damage mechanism,hysteresis hoop,stiffness degradation law,deformation capacity of structure and energy dissipation capacity of BRB were studied by static cycle loading test.Results show that the system has plump hysteresis hoop,the BRB and RCFB can effectively work together to resist lateral force,terefore,the energy dissipation mechanism of this system can be realized.The measured axial force-axial displacement curve of the BRB shows that its energy dissipation effect is remarkable and the damping ratio of the structure increases.Suggestions are put forward for the shear structural design of the deaerator room and the two layers at the bottom of the coal-bunker room,the design of the weak parts of the rigid layer(it is composed of steel beams,steel braces and concrete beams)in coal-bunker room,the form of BRB and the model design test of a single structure.