Bolted and hybrid beam-column joints between I-shaped FRP profiles

Presented are test results from five full-scale pultruded FRP beam-to-column joints subjected to cyclic loading. The parameters include cleat position, connection method and cleat material. The joints’ behaviour is assessed through hysteresis moment rotation loops, accumulated dissipated energy and failure patterns. The hybrid joints with steel cleats showed the best overall cyclic performance with accumulated dissipated energy 75% higher than the bolted joint. The bolted joint with FRP cleats exhibited the lowest dissipated energy, four times lower than the joint with steel cleats. The cyclic performance of web and flange cleated joint was same as flange cleated joint. Three failure patterns were noticed, namely shear-out failure of the beam’s bolted region (bolted joint with steel cleats), adhesive debonding followed by shear-out failure (hybrid joint with steel cleats) and delamination cracking (bolted joint with FRP cleats).