STUDY ON THE BEHAVIOR OF BEAMS REINFORCED WITH CFRP RODS SUBJECTED TO TORSION

This paper is an experimental investigation of carbon fiber reinforced polymer beams subjected to torsion and compared with conventional concrete beams. In this experiment four CFRP beams and four conventional concrete beams were fabricated and tested. This study focused mainly on general cracking characteristics, pre cracking behavior, post cracking behavior and analysis, minimum torsional reinforcement, torsional reinforcement, ductility, crack width and stiffness. It was observed that the torsional behavior CFRP bar was comparable to conventional concrete. Compare to an ACI prediction, equation suggested by Macgregor was more conservative in calculating cracking torsional resistance. But for the calculation of ultimate torque strength ACI prediction was more conservative in this regard which was under estimated compared to ACI and Macgregor equations. Minimum torsional reinforcement in beams was necessary to ensure that the beam did not fail in cracking. Compared to conventional concrete specimens, CFRP specimens had more ductility. Crack width at initial cracking torque for both conventional and CFRP beams with corresponding reinforcement ratios was almost similar