Influence of stirrup ratio on size effect of shear strength of concrete beam-column joints reinforced with CFRP bars

Abstract

<p indent="0mm">The shear failure behavior and the size effect of shear strength of carbon fiber-reinforced plastic (CFRP)-reinforced concrete beam-column joints are investigated in this study. The finite element model for failure analysis of CFRP-reinforced concrete beam-column joints was established using a mesoscale numerical method. The mesoscale failure mode and failure mechanism of geometrically similar CFRP-reinforced concrete beam-column joints were studied, and the influence of CFRP-bar ratio on shear strength and size effect law of joints was discussed. The simulation results show that the nominal shear strength of CFRP-reinforced concrete beam-column joints has an obvious size effect, and the size effect of shear strength can be alleviated by increasing the CFRP-bar ratio. In addition, it is found that the size effect of the nominal shear strength of concrete beam-column joints with CFRP bars is more obvious than that of reinforced concrete (RC) beam-column joints. Based on the size effect law of nominal shear strength for RC beam-column joints, considering the effect of stirrup ratio proposed in the previous work, along with the numerical test results in this study, the size effect law was extended and established for the analysis of nominal shear strength of concrete beam-column joints with CFRP bars.