Abstract: Based on the experimental study, the appropriate constitutive models are selected and the fiber model method is adopted to analysis the load-displacement and moment-curvature skeleton curves of PVC-CFRP confined concrete column-RC ring beam interior joints under low cyclic loading. The influence of the concrete strength of joint area, ring beam height, column diameter and longitudinal reinforcement ratio of frame beam on the skeleton curves of the specimens are investigated on the basis of the verified accurate numerical model. The results show that the bearing capacity and ductility of the specimens increase with the increase of frame beam height, column diameter and longitudinal reinforcement ratio of frame beam. The bearing capacity of the specimens increases while the ductility decreases with the improvement of concrete strength of joint area. On the basis of the analysis results of the test and numerical simulation, considering the economy and rationality of the ring beam joints, it is suggested that the concrete strength of the joint area should not exceed C60, the height of the ring beam should be 340~440 mm, and the ratio of the ring beam width to the column diameter should be controlled between 0.33~0.50.

Key words: PVC-CFRP confined concrete, ring beam joint, numerical simulation, load-displacement relationship, moment-curvature relationship, composites