Innovative Concrete Members Reinforced with Durable FRP Bars

This study investigated the torsional performance of the rectangular concrete beams reinforced in the longitudinal direction with GFRP bars and rectangular GFRP continuous spirals in the transverse direction. Three beams were reinforced with rectangular spiral spacings of nil, 200 mm, and 100 mm at the transverse reinforcement ratios of zero, 0.4%, and 0.90, respectively. The test findings revealed that the GFRP spirals achieved 38 and 148% high post-peak torque for specimens BG200 and BG100, respectively, compared to their corresponding cracking moment due to their superior tensile resistance provided. The failure mode of the tested specimens with volumetric ratios of 0.40% and 0.90% was triggered by the rupturing of GFRP rectangular spirals at their bent portions.