Numerical Analysis Of Mechanical Performance Of A Fabricated Joint Between Concrete-filled Tubular Column And Steel Beam

In this paper, the new type fabricated joints between concrete-filled tubular column and steel beam are performed to simulate by the ABAQUS software. The model comparatively accurately showed that the joints’mechanical properties under the low-reversed cyclic loading. The main achievements can be summarized as follows:(1) Based on appropriate material stress-strain relations and failure criteria, this paper established the tested joints’three-dimensional nonlinear finite element model using the ABAQUS software. Comparison analysis indicates that finite element analysis results agree well with experiment results. The finite element models with certain accuracy are analyzed to study the tested joints’ force mechanism at different stages. Meanwhile, parametric analysis were conducted on the tested joints, it is found that core concrete and steel tube thickness are the main factors for the tested joints’mechanical properties, but not axial compression ratio and concrete intensity.(2) Aim at the structure defects of the tested joints, a new improved joint is presented. Nonlinear finite element analysis of the new fabricated joints between concrete-filled tubular column and steel beam is conducted under the low-reversed cyclic loading. Stress and stain distribution and hysteretic behavior of the new joints are obtained. The result indicates the new improved joint is superior to the tested joint. Through the analysis of the new improved fabricated joints’mechanical behavior and working mechanism, we can know that the new improved fabricated joints of the force failure mechanism and seismic behavior.(3) Several new improved fabricated joint models are established to investigation the influence law of the new joints’hysteretic behavior, stiffness degradation, displacement ductility ratio at different axial compression ratio, concrete intensity, steel tube thickness and beam web height. The results show that the new improved fabricated joints offer the advantages of steady performance, and the certain axial compression ratio, steel tube thickness and beam web height can improve the new joints’ mechanical properties, but not concrete intensity.