目的研究环板宽度和柱轴压比对方钢管混凝土柱-钢梁外加强环节点力学性能的影响.方法采用ABAQUS有限元程序,对方钢管混凝土柱-钢梁外加强环节点进行非线性分析,计算和分析了外环板节点受力的荷载-变形全过程关系曲线.结果给出了有限元计算中钢材和混凝土本构关系模型、钢管及其核心混凝土之间界面模型等确定方法,分析柱端水平荷载-水平位移(P-Δ)骨架曲线,并提出了合理的环板宽度设计建议,理论计算结果与试验结果吻合较好.结论柱轴压比的增大和环板宽度的减小,都会降低节点水平极限承载力;按现有规程设计外加强环是安全可靠的,但环板宽度可按2/3设计就已满足抗震要求的承载力和刚度.
To study the effects of width of stiffening ring and axial load level of the column on the behavior of beam-to-column connections, nonlinear finite element method (FEM) analysis on steel beam-to-concrete filled steel tube (CFST) column connections with external stiffening rings was carried out by ABAQUS software. Determination methods for the constitutive models of steel and concrete, interface model between the steel tubes and the core concrete were presented. The lateral load (P) versus lateral displacement (Δ) envelope curves were analyzed and validated by the experimental results. Reasonable design of width of stiffening ring was proposed. The results showed that load-bearing capacities of connections decreased with a reducing of width of stiffening ring or an increasing of axial load level. In addition, the load-bearing capacities of CFST connections with 2/3 times width of stiffening ring designed by present specifications can satisfy their requirement of strength and stiffness for earthquake-esistance.