异形钢管混凝土柱外套板式节点试验及数值模拟研究

Test and Numerical Simulation Study of New Type Concrete-filled Steel Tube Column Coated Slab Joints

本文提出一种异形钢管混凝土框架角柱外套板式节点。针对节点制作1种异形柱外套板式(BASE)试件进行拟静力试验,取得节点的滞回曲线、骨架曲线和破坏模式等。对BASE节点进行有限元模拟,验证了模型的正确性;对验证后的有限元模型进行变参数分析,研究外套板厚度、T型件翼缘厚度对节点承载力、耗能能力和延性的影响。试验结果表明:节点主要靠螺栓滑移和H型钢梁屈曲耗能,H型钢梁所形成塑性铰远离节点核心区域,属于典型的延性破坏,符合“强节点弱构件”的设计原则;参数分析中增加节点外套板厚度对节点的耗能能力和延性有一定提升,极限承载力没有较大变化;同时,随着T型件翼缘厚度增加,节点延性逐渐增大,耗能能力明显提升,极限承载力出现逐渐提前。

A new type of special-shaped CFST(concrete-filled steel tube)frame corner column jacketed plate joint is proposed.A special-shaped column coated slab(BASE)specimen is made for the node to conduct a quasi-static test,and the hysteresis curve,skeleton curve and failure mode of the node are obtained.The finite element simulation of the BASE node is carried out to verify the correctness of the model;The variable parameter analysis of the verified finite element model is carried out to study the influence of the thickness of the outer shell and the thickness of the flange of the T-shaped piece on the bearing capacity,energy dissipation capacity and ductility of the joint.The test results show that the joints mainly rely on bolt slip and H-beam buckling energy dissipation,and the plastic hinges formed by the H-beams are far from the core area of the joint,which is a typical ductile failure and conforms to the design principle of“Strong joints and weak specimen”;Parameters in the analysis,increasing the thickness of the outer shell plate of the node has a certain improvement in the energy dissipation capacity and ductility of the node,and the ultimate bearing capacity does not change greatly;At the same time,with the increase of the thickness of the T-shaped flange,the ductility of the node gradually increases,and the energy dissipation capacity is significantly improved.The ultimate bearing capacity appears gradually ahead.