FRP reinforced/prestressed concrete members: A torsional design model

The torsional design provisions of the Canadian standard S806 for fiber reinforced polymer (FRP) reinforced (RC) or prestressted (PC) concrete members are presented and their theoretical and empirical justifications are provided. The key parameters governing the nominal torsional strength are identified and their appropriate values for FRP-RC/PC members are specified. The accuracy of the method is evaluated by analyzing 27 FRP-RC/PC members tested under pure torsion by other investigators. The CSA method is able to reasonably predict the torsional strength of these beams. It is also shown that the cracking torque can be predicted using the formulas in the ACI and AASHTO LRFD codes without any modification. Some considerations with the statements of CNR-DT 203, fib 40, JSCE guidelines are also carried out.