方钢管混凝土柱塑性变形性能的试验研究

Experimental study on seismic behavior of concrete filled square steel tubular columns to low-cycle reversed horizontal load

提出了允许部分柱屈服的混合型屈服机制,允许部分方钢管混凝土柱屈服耗能,但要求柱不丧失承载力以避免层倒塌,为考察方钢管混凝土柱屈服后的力学性能,对方钢管混凝土柱在低周反复荷载作用下的力学性能进行了试验研究,分析了轴压比、含钢率、长细比等参数对方钢管混凝土柱滞回曲线、刚度曲线、延性系数、塑性变形性能的影响.试验结果表明:方钢管混凝土柱屈服后承载力无明显下降,具有良好的延性和耗能能力,且随含钢率的增加,钢管混凝土柱的耗能能力和塑性变形能力提高;而随轴压比和长细比的增大,钢管混凝土柱的耗能能力和塑性变形能力却相应降低.

A new global failure mechanism frame with some columns yield was proposed by the authors, some columns are allowed to yield and dissipate energies, which would not lose its bearing to avoid layer collapse. Six concrete filled square steel tubular columns are experimented under low cyclic load for studying its mechanical performance. Test results includ- ed the hysteretic curves, rigidity curves and plastic deformation. The influence of such parameters as slenderness ratio, axial compression ratio and sectional steel ratio are analyzed. The plastic deformation and capacity of energy dissipation will improve along with sectional steel ratio increase; and the plastic deformation and capacity of energy dissipation will reduce along with slenderness ratio and axial compression ratio increase.