方钢管混凝土柱-外包钢混凝土组合梁连接节点滞回性能分析

Analysis on hysteretic behavior of concrete-filled square steel tubular column to steel-encased concrete composite beam connections

提出了一种新型的方钢管混凝土柱与外包U形钢混凝土组合梁连接节点形式:隔板贯通部分钢筋贯穿式节点。设计了3个节点试件,对其进行低周反复荷载试验,利用ANSYS软件对低周反复荷载作用下的节点试件进行非线性有限元分析并与试验结果对比。结果表明:有限元分析得到的节点破坏形态、应力分布、滞回曲线、骨架曲线与试验结果吻合较好。在此基础上,对发生梁端塑性铰破坏模式的节点滞回性能进行参数分析,研究楼板厚度、U形钢壁厚、组合梁纵向受力钢筋配筋率、贯通隔板厚度以及轴压比对节点滞回性能的影响。研究结果表明:楼板厚度和U形钢壁厚对节点滞回性能有显著的影响,组合梁纵向受力钢筋配筋率对节点滞回性能影响较为显著,贯通隔板厚度和轴压比对节点滞回性能影响很小。

A new type of concrete-filled square steel tubular column to steel-encased concrete composite beam connection was proposed, which was the part reinforcement-through with diaphragm-through connection. 3 specimens were designed and tested under low-cycle reversed loading. Based on the experimental studies, nonlinear finite element analysis was conducted using ANSYS. The failure mode, stress distribution, hysteretie curves and backbone curves obtained from the finite element analyses were in good agreement with the experimental results. Based on the finite element model, the parametric analyses of hysteretic behavior were conducted on the connections in which the plastic hinge is formed at the beam end. The influences of the floor thickness, the thickness of U-shape steel, the ratio of longitudinal reinforcement, the thickness of through diaphragm and the axial compression ratio on the hysteretic behavior were investigated. The results show that the floor thickness and the thickness of U-shape steel have a significant influence on the hysteretic behavior for the connection . The ratio of longitudinal reinforcement in the beam has some effects on the hysteretic behavior. The thicknesses of through diaphragm and the axial compression ratio have little influence on the hysteretic behavior.