钢-混凝土组合梁与钢管混凝土柱节点的非线性有限元分析

以简化的Varma模型作为钢材的循环本构关系模型,建立了2类钢管混凝土柱与组合梁连接节点——梁钢筋贯通钢管节点和梁钢筋与上加强环焊接连接节点的三维非线性分析模型,并采用有限元软件ANSYS对其在低周反复荷载作用下的滞回性能进行了非线性分析。结果表明：由有限元模型得到的低周反复荷载作用下的滞回曲线及骨架曲线与试验所得的结果吻合较好,但在屈服荷载后差异较大;如能恰当地选择材料的本构关系、计算模型和破坏准则,则能够采用有限元模型准确地预测上述2类节点的弹塑性行为和整体抗震性能,并用于节点滞回性能的非线性参数分析。

Nonlinear Finite Element Analysis of Steel-concrete Composite Beam to Concrete-filled Steel Tubular Column Joints

The cyclic constitutive relation of steel was proposed, which is a simplified Varma＇s model. Nonlinear 3-D finite element models （FEM） of two kinds of joints, namely steel bars headed through the pipe joint and steel bars welded with the upper strengthened ring joint, under the cyclic loading by using finite element software ANSYS were established. The nonlinear analysis of the above two kinds of concrete-filled steel tubular column to steel concrete composite beam joints was conducted. The results show that the hysteretic curves and skeleton curves from FEM under low cycle reversed loading agree well with those of the cyclic loading tests. If the material constitutive relation, calculation model and failure criterion can be selected suitably, the FEM can accurately predict the overall seismic behavior and the inelastic performance of these two kinds of joints, and can be used to conduct the nonlinear parameter analysis of the joints hysteretic behavior.