圆钢管约束型防屈曲支撑抗震性能试验

摘要

Three types of buckling restrained bracing (BRB) members with circular steel pipe constraint were made,including circular steel pipe external constraint with cross section core and circular steel pipe core,circular steel pipe internal constraint with circular steel pipe core.Pseudo static tests were carried out to study the seismic performance of BRBs with circular steel pipe constraint.The parameters of specimens were analyzed and compared to study the effects of different types of BRBs.The results show that the BRBs with external constraint have good hysteretic behavior.However,the BRBs with internal constraint tend to suffer from the overall instability and have poor hysteretic behavior.The bearing capacity and initial secant stiffness increase with the increase of cross section area of the core element.The equivalent viscous damping coefficients of the components with different core sizes and interlayer thicknesses are almost the same.The equivalent viscous damping coefficients of the external constraint BRBs can reach above 0.50.And value of the BRBs with steel pipe circular core elements is slightly lower than that with a cross section.%制作了3种圆钢管约束防屈曲支撑构件,分别为圆钢管外约束加十字截面芯材构件、圆钢管外约束加圆钢管芯材构件以及外侧圆钢管加内部圆钢管约束构件.对3种构件进行了拟静力试验,研究了圆钢管约束防屈曲支撑构件的抗震性能和参数影响规律,对比了不同类型的防屈曲支撑的抗震效果.研究结果表明:外约束防屈曲支撑构件都具有良好的滞回性能,内约束防屈曲支撑构件因容易发生整体失稳,滞回性能较差;相同截面类型的构件,承载力和初始割线刚度随核心单元截面面积的增大而增强;不同芯材尺寸和隔层厚度构件的等效粘滞阻尼系数基本趋于一致;外约束防屈曲支撑构件的等效粘滞阻尼系数均大于0.50,圆钢管芯材构件的等效粘滞阻尼系数略小于十字截面芯材构件.