钢管混凝土柱-不等高钢梁组合节点有限元分析

FINITE ELEMENT ANALYSIS ON COMPOSITE JOINTS WITH CFST COLUMNS AND UNEQUAL HEIGHT STEEL BEAMS

为研究由钢管混凝土柱不等高钢梁构成的组合节点滞回性能,基于简化力学模型和合理的材料本构模型,考虑钢管与混凝土之间的非线性接触,采用ABAQUS有限元软件建立了该类组合节点局部细化的有限元模型,并对4个该类组合节点进行了反复加载下的滞回分析,获得试件的荷载-位移滞回曲线和骨架曲线,结果表明该类组合节点滞回曲线比较饱满,耗能能力较强。将模拟的滞回和骨架曲线与已有试验结果进行对比,二者吻合良好,验证了有限元建模的合理性和可行性,最后给出该类节点具体的抗震加强构造措施,为后续采用此类节点的框架抗震性能研究奠定基础。

In order to study the hysteretic behavior of composite joints composed of concrete-filled steel tubular(CFST)columns and steel beams with unequal height,based on the simplified mechanical model and reasonable material constitutive model,considering the nonlinear contact between steel tube and concrete,a local refined finite element model of this kind of composite joint was established by using ABAQUS finite element software,and the hysteretic analysis of four such composite joints under repeated loading was carried out.The load displacement hysteretic curves and skeleton curves of the specimens are obtained.The results show that the hysteretic curves of the composite joints are full and the energy dissipation capacity is strong.Comparing the simulated hysteretic and skeleton curves with the existing test results,both of them are in good agreement,which verifies the rationality and feasibility of the finite element modeling.Finally,the concrete anti-seismic strengthening structural measures of this kind of joint are given,which lays a foundation for the subsequent research on the seismic performance of such joints.