钢管混凝土柱与钢梁单边高强螺栓端板连接框架拟动力试验

Pseudo-dynamic Testing of CFST Column-to-steel Beam Frames with High-strength Blind-bolted Endplate Connections

为了研究地震作用下半刚性钢管混凝土框架结构的动力性能与破坏机理,进行了两榀钢管混凝土柱与钢梁单边高强螺栓端板连接框架的拟动力试验,以El Centro波作为拟动力试验的激励输入,获得不同地震加速度峰值下结构的动力响应和破坏模式.分析了在地震作用下组合框架的滞回曲线、动力放大系数、阻尼比、刚度退化规律和耗能能力等抗震性能指标,研究了结构在不同地震波阶段的位移时程曲线和加速度时程曲线等动力响应,比较了柱截面形式和端板类型对组合框架结构抗震性能的影响.试验结果表明,在柱截面宽度和含钢率相同条件下,采用单边高强螺栓端板连接,方钢管混凝土框架的刚度大于圆钢管混凝土框架,但其延性系数小于圆钢管混凝土框架;该类型半刚性组合框架具有良好的抗震性能,连接可靠,可以在实际工程中推广和应用.

To investigate dynamic performance and failure mechanism of semi-rigid concrete-filled steel tubular（ CFST） frame,two specimens of CFST column-to-steel beam frames with highstrength blind bolted endplate connections were conducted by pseudo-dynamic tests. With El Centro seismic wave as the simulated seismic excitation input of pseudo dynamic test,dynamic response and failure mode of the frames was obtained under differ acceleration earthquake waves. Hysteretic behavior,amplification coefficient,stiffness degradation and energy dissipation capacity were analyzed. Displacement and acceleration time history response curves were also evaluated. The effect of column section type and endplate type on seismic behavior of the typed frame was compared. The test results showed that at the same steel ratio of the column section,the stiffness and ductility coefficients of square CFST frame were higher and lower than those of circular CFST frame respectively. The proposed semi-rigid CFST composite frames can provide good seismic behavior and reliable connection. It can be popularized and applied in engineering practice.