方钢管混凝土柱-钢梁双侧板贯穿式节点抗震性能试验研究

双侧板贯穿式节点是基于钢管混凝土柱横向受力特点而提出的一种新型梁柱连接节点。对6组17个十字形节点进行静力和拟静力试验研究,分析节点核心区的受力特点及抗震性能,结果表明:塑性铰均发生在穿心板外的钢梁上,调整竖向穿心板长度可以控制塑性铰发生的位置;双侧板贯穿式节点可有效地减缓钢梁上翼缘与钢管柱连接处的应力和应变梯度,减小节点核心区所受剪力,削减梁柱连接焊缝应力峰值,从而提高结构体系的耗能能力;所有节点试件的滞回曲线饱满,强度和刚度退化不明显,延性好,耗能能力强;不同类型和尺寸竖向穿心板的节点试件整体抗震性能差别不大。研究成果可供矩形钢管混凝土组合结构抗震设计参考,丰富钢管混凝土柱-钢梁节点的类型,促进钢管混凝土组合结构在工程中的进一步推广应用。

Experimental study on the seismic behavior of the dual vertical diaphragms through joint connection between concrete-filled square steel tubular column and steel beam

Based on the transverse mechanical behavior of concrete-filled square steel tubular column,a new dual vertical diaphragm through joint connection between concrete-filled square steel tubular column and steel beam was proposed.Seventeen specimens in seven groups were tested under static and low-cycle reversed loadings at the ends of the beams.The results indicate that the dual vertical diaphragms through joint connection effectively reduced the stress responses and the strains of the connection area between concrete-filled square steel tubular column and steel beam,protected the joint core,moved the plastic hinge from the root of the beam to outside the diaphragm,cut down the core zone shear of the joint and the joint weld stress between beam and steel tubular column,and that the placement of a plastic hinge can be controlled by the different lengths of the diaphragm,which help increase the integral structural energy dissipation capability.The hysteresis loops of the specimens were plump when the maximum loading was reached and the degradation of strength and stiffness was not significant.All specimens have very good ductility and energy dissipation capability.The seismic behaviors with different diaphragm types and different dimensions showed no obvious difference,but they influenced the strain responses of the joint zone.