钢筋加劲T形截面钢管混凝土柱抗震性能试验研究

制作4根钢筋加劲的T形截面钢管混凝土柱、1根非加劲T形截面钢管混凝土柱和1根T形截面钢筋混凝土柱试件，对其进行低周往复水平荷载作用下的滞回性能试验，研究其破坏模式和滞回性能，分析钢筋加劲肋的作用机理以及钢管对混凝土的约束作用。结果表明：相比T形截面钢筋混凝土柱，T形截面钢管混凝土柱破坏程度有明显减轻，刚度、承载力以及耗能性能均有明显提高；钢筋加劲肋能有效限制钢板局部屈曲和阴角处钢管与混凝土脱离，保证钢管和混凝土共同工作，对拉钢筋加劲肋相对锯齿形钢筋加劲肋的效果更加显著；含钢率较高的钢管混凝土柱承载力更高,耗能能力更好；轴压比从0.2增加到0.4时，钢筋加劲的T形截面钢管混凝土柱的承载力增大，延性降低。

Experimental research on seismic behavior of T-shaped concrete-filled steel tube columns with reinforcement stiffeners

Five T-shaped concrete-filled steel tube(CFST) column specimens including four stiffened columns and one non-stiffened column and one reinforced concrete(RC) column were fabricated and researched by quasi-static experiment under cyclic loading.Failure modes and hysteretic properties of specimens were investigated.The mechanism of reinforcement stiffeners and the constraining effect provided by T-shaped tube were also studied.Experimental results reveal that: compared with T-shaped RC columns,T-shaped CFST columns have positive effect on failure mode,initial stiffness,bearing capacity and energy dissipation capacity;the reinforcement stiffeners can effectively postpone steel tube’s local buckling and restrain separation of steel tube and concrete at concave corners,to guarantee the interaction of steel tube and concrete;due to fully utilization of stiffeners’ tension capacity,the tension reinforcement stiffeners’ restricting function is more significant than that of serrated-shaped reinforcements;the CFST columns with larger steel ratio have high bearing capacity and better energy dissipation capacity;with the axial compressive ratio varying from 0.2 to 0.4,the bearing capacity of CFST specimens increases but the ductility decreases.