Experimental and Numerical Investigations of PVC-FRP Confined Concrete Column-RC Beam Joint Reinforced with Core Steel Tube under Axial Load

The axial compressive behaviors of the PVC-FRP Confined Concrete (PFCC) column-Reinforced Concrete (RC) Beam Joint reinforced with Core Steel Tube (CST) are investigated thoroughly using experimental and numerical methods in this study. The test programme is carried out on nine PFCC column-RC beam joints reinforced with CST (PCRBJ-CST). To systematically investigate the PFCC column-RC beam joints and reasonably design this structural connection components, all specimens are designed by principle of "strong column-weak joint". Different variable parameters including the stirrup ratio of joint core, joint height, length of CST and reinforcement ratio of CST are considered. The test results demonstrate that, as the design expected, all the specimens fail by crushing of the concrete of joints, while the PFCC columns aren't damaged. Test results indicate that the stirrup ratio of joint core, joint height and reinforcement ratio of CST have significant impacts on carrying capacity, deformation and stiffness. Subsequently, a verified finite element (FE) model for the PCRBJ-CST under axial load is developed. Additionally, the applicability of existing codes to predict carrying capacity of PCRBJ-CST is evaluated based on experimental data.