芯钢管连接的钢管混凝土半连通角节点非线性有限元分析

Nonlinear Finite Element Analysis of Semi-connected Corner Joint with Core Steel Tube in Concrete Filled Steel Tube

应用有限元分析软件ANSYS对一种新型的芯钢管连接的半连通钢管混凝土柱和钢筋混凝土梁角节点进行非线性分析。确定单元类型、材料本构关系、破坏准则和梁端荷载,利用对称性建立的三维实体模型分析模型中梁、柱、外钢管、节点芯钢管、环箍、竖向钢筋和混凝土的应力状况。研究模型破坏过程、受力性能、破坏机理以及模型破坏的原因,并将有限元分析结果与模型试验结果进行了对比分析,互相验证了分析结果的正确性。证实这种新型节点的合理性、可行性,指出节点还有较大的承载潜力,满足"强柱、弱梁、节点更强"的抗震设计原则,用于实际工程有望解决节点传递弯矩能力弱、刚度差、构造复杂、施工不便等问题。

The new joint connects concrete filled steel tubular （CFST） column and RC＇beam. The element types, the material constitutional relationship and the failure criterion are confirmed, and the load at beam end is simplified. Based on the symmetrical character, the three-dimensional model is presented to analyze the stress status of the members in the joint model, including the beam, the column, the outer steel tube, the joint core steel tube, the hooping, the vertical reinforcement and the concrete. The forced behavior, the failure mechanism and the cause of the model failure are studied. The results of the model test are compared with the results of the finite element analysis. By the comparative results, the correctness of the analysis results is validated, and the rationality and feasibility of the new type joint are approved. The results also indicates that the joint still has potential bearing capacity. The joint model meets the seismic design principles ＂strong column, weak beam, stronger joint＂. In the actual projects, it will solve lots of the problems, such as the weak capability of the joint in passing the moment, the weak stiffness, the complex conformation and the inconvenience construction.