方钢管混凝土柱—削弱钢梁端栓焊连接节点受力性能

采用三维实体单元，对“带内隔板的方钢管混凝土柱-削弱梁端钢梁栓焊连接框架节点”建立了考虑几何非线性、材料非线性和接触非线性的有限元理论分析模型，将有限元模型与试验模型进行对比分析，规律方面吻合较好，进而对“框架节点”在单调和低周反复荷载作用下的受力性能进行了数值分析，深入研究了其荷载-位移曲线、节点区梁端的应力分布规律、耗能能力及破坏特征。研究表明：各种粱端削弱节点P-△曲线的初始刚度和梁端无削弱节点的初始刚度基本相同；梁端削弱节点的承载力比梁端无削弱节点的承载力有所降低，但降低幅度不大；梁端削弱节点均能够将塑性铰外移致梁端削弱区域；各种削弱形式的梁端削弱节点均表现出良好的延性及耗能能力，具有较好的抗震性能。

Mechanical Behavior of Bolt-weld Joints between Square Concrete-filled Tubular Column and Reduced Beam Section

With the actual three-dimension element, the nonlinear finite element analytic models were established for bolt-weld joints between square concrete-filled tubular （CFT） column and reduced beam section with inner separates, considering geometric large deformation, materials nonlinear and contact nonlinear. Compared with finite element model and experimental model, it was in good agreement in principle. And the characteristics of load-displacement（P-Δ） curves, the stresses distribution of beam, the dissipating energy ability and destruction form were made with numerical analysis for bearing behavior of bolt-weld joints between square CFT column and reduced beam section . It was shown that the initial stiffness of joint with reduced beam section was close to that of non-reduced beam section joint. The bearing capacities of joints with reduced beam section were a little bit lower than those of non-reduced beam section joint. The plastic hinge in the joint with reduced beam section moved to the reduced beam region. The studied joints displayed a better ductility, energy dissipation and good seismic behavior.