The rehabilitation of concrete structures using Fiber Reinforced Polymer (FRP) materials has become a growing market in the construction industry over the last few years. Many research projects in Canada and elsewhere in the world were carried out to promote this efficient repair technique to extend the service life of these structures. However, most of the research was focussed on the flexural reinforcement. As the results, the flexural design methods are well developed and accepted in the design offices. In contrary, few researchers have proposed design methods to evaluate the shear capacity of beams strengthened in shear by FRP. This paper will review the different FRP shear design methods found in the literature and compare the adequacy of each method by using the test results from the University of Alberta. The FRP shear design methods presented include: the effective FRP strain and the bond mechanism criteria, the Strut and Tie model, the Modified Compression Field Theory (MCFT), and a mechanical model based on the shear friction approach. Sixteen full scale T-beam test results were used in the comparison. Two web heights of 250 and 450 mm and two ready mix concrete batches of 29 and 44 MPa were used in the test specimens. Closed stirrups were used with three spacings: 200 mm, 400 mm and no stirrups. Three types of FRP were used to strengthen externally the web of the T-beams: a) uniaxial glass fibre; b) triaxial [0/60/-60] glass fibre; and c) uniaxial carbon fibre. The results showed that the shear friction approach evaluates better the FRP shear contribution. The predicted capacities from this mechanical model are also found conservative and in excellent agreement with the test results.
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