Shear Strengthening Effects with Varying Types of FRP Materials and Strengthening Methods

Synopsis: The FRP system is a good alternative of the traditional shear strengthening technique. This study evaluates the shear strengthening effects on the reinforced concrete beams strengthened with varying types of FRP materials, CFRP, CFS and GFRP. The entire strengthened specimens were failed in the mode of brittle shear failure with debonding of the FRP materials. The shear capacities were improved mostly by more than 54%. The different types of the strengthening materials did not yield a noticeable difference in the shear strengthening effect. The orientation of the fibers, however, was found to be an important factor. With a 45° fiber orientation, greater strengthening effect and better control on the shear crack propagation were observed. A numerical model predicting the shear capacity of the shear-strengthened beams was suggested along with the strength efficiency factor from the test results. The predictions were in good agreement with the test results.