Analytical models of horizontal shear stress and failure mode for reinforced concrete beam-column joints externally retrofitted with FRP sheets and steel anchor bolts

This research presents the development and validation of both seventeen finite element (FE) and twenty-four analytical models aimed at predicting the performance and shear capacity of beam-column joints retrofitted with Fiber Reinforced Polymer (FRP) in different configurations. The FE models account for key factors such as joint geometry, material properties, and reinforcement layouts to accurately simulate joint behavior under cyclic loads . Utilizing ABAQUS, were compared with prior experimental findings, demonstrating high accuracy, with load-bearing capacity predictions ranging from 0.93 to 1.12 and displacement estimations between 0.88 and 0.96. Once validated, indicated that combining FRP with steel anchor bolts significantly increases both the load capacity and stiffness of the joints. However, FRP debonding was identified as the primary failure mode in all configurations. Additionally, the analytical model developed in this research produced reliable predictions for shear strength , with deviations between predicted and experimental results falling between 0.91 and 1.09 for joints reinforced with FRP and steel anchor bolts. Overall, both FE and analytical models highlight the potential of using FRP in combination with steel anchor bolts to enhance the structural integrity and performance of beam-column joints, although further work is necessary to mitigate FRP debonding. • FE validation matches experiments, with load 0.93–1.12 and displacement 0.88–0.96. • Model predicts shear strength of RC joints retrofitted with FRP and steel bolts. • Model validation showed 0.98 difference for FRP and 0.91–1.09 for FRP-steel bolts.