Research On Flexural Capacity Of RC Beam-CFST Column Joint Connected With Ring Beam

RC beam-CFST column joint connected with ring beam is a new node form. It’s welded steel on the outer surface of CFST as shear ring and pouring concrete ring beam around it. Passing moment by concrete ring beam surrounded the steel tube and passing shear by shear ring and the static friction arising from the distortion of ring beam between concrete and steel tube. It has good deformation capacity and energy dissipation capacity. RC beam-CFST column joint connected with ring beam can be applied to high-rise building structure, has good prospects for engineering applications. Research on its mechanical performance, ultimate bearing capacity and structural failure modes has important theoretical significance and application value.Compared with other node forms, there’s no hole in the node region and beam, column relatively independent, this node has great stiffness, the damage of the node does not affect the integrity of column and meet the requirements of strong column weak beam, strong node weak components in seismic design, its superiority is obvious.Since the ring beam joint has been proposed, too many static and low cyclic experiments have been made. For absence of the numerical finite element simulation, we can’t know each parts detail visually. On the basis of the research of other scholars for this problem, the software ABAQUS has been used to simulate the ring beam joint, so as to know the mechanics mechanism、force transmission path and the ultimate failure mode. Discuss the affection of ring beam section and frame beam section longitudinal reinforcement ratio、the strength grade of concrete and other parameters to the mechanical behavior of this node under monotonic load and cyclic load. The result show that the ring beam and joint has high stiffness and load capacity, good ductility and energy dissipation capacity. We can make the appearance of plastic hinges out of the node area by controlling the stiffness ratio of the ring beam and frame beam. Satisfy the seismic design of "strong nodes, weak component "of the design requirements.