往复荷载作用下钢管混凝土叠合柱-钢梁连接节点力学性能研究

建立了钢管混凝土叠合柱-钢梁连接节点在往复荷载作用下力学性能分析的有限元计算模型。利用平面与空间连接节点试验结果，对建立的数值模型进行验证。采用有限元模型分析不同空间双向加载方式对钢管混凝土叠合柱-钢梁空间连接节点力学性能的影响规律，研究该类组合节点在往复荷载作用下荷载(P)-位移(Δ)关系全过程受力机理与核心区剪力分配机制，并从承载力及刚度等方面对比平面与空间连接节点的性能。研究结果表明，不同加载方式对节点的承载力有明显影响。相比平面节点，钢管混凝土叠合柱-钢梁空间连接节点在双向往复荷载作用下正、负向承载力分别降低约14%和18%。

Behaviour of concrete-encased concrete-filled steel tubular column to steel beam joints under cyclic loading

A nonlinear 3-D finite element is presented to analyze the behavior of concrete-encased concrete-filled steel tubular column to steel beam joints. The proposed finite element model is verified by experimental results of both planar and spatial joints. The effect of different loading paths on the behaviour of such spatial joint is analyzed. The full-range load-displacement envelope curve of the joint and the shear-force distribution of panel zone under bi-directional loading are also investigated. The capacity and stiffness of the spatial joints are compared with those of the planar joints. It is found that the capacity of the composite joint is influenced by the loading path. The positive and negative capacities of the spatial joint under bi-directional loading are about 14% and 18% lower than those of the planar joint, respectively.