复式钢管混凝土外钢管不连通环梁节点有限元分析

Finite element analysis on the ring beam joint with discontinuous outer tube between composite CFST and RC beams

基于复式钢管混凝土外钢管不连通环梁节点的试验研究,在合理选择材料本构关系和破坏准则的基础上,采用有限元分析软件ANSYS建立模型,研究了该类节点在往复荷载作用下的力学性能。有限元模拟的滞回曲线及骨架曲线与试验结果大致吻合,在一定程度上验证了有限元方法的合理性。在此基础上,分析了钢筋混凝土环梁及内外钢管的应力分布,探索此类节点的传力机制及最终破坏形态。最后对该类节点进行了参数分析,研究节点处竖筋配筋率、竖筋锚固长度、节点核心区及环梁处混凝土强度等级、框架梁混凝土强度等级对骨架曲线的影响规律。

According to experimental study on the ring beam joint with discontinuous outer tube between composite concrete- filled steel tube and reinforced concrete beams, the finite element software ANSYS was used to simulate the behavior of connections. The simulated hysteretie curves and skeleton curves were compared with the experimental data and roughly agreement can be observed. Stress analysis was researched by using the finite element analysis model to study the failure mode and mechanism of the new system joints. Moreover, parametric studies have been carried out to investigate the influences of the cross-section ratio and anchorage length of the vertical reinforcement for the nodes area, the strength of the concrete for the nodes area and the ring beams and the concrete strength of the frame beams on the skeleton curves.