Abstract
Use of externally bonded Fiber Reinforced Polymer (FRP) sheets/strips/plates is a modern and convenient way for strengthening of RC beams. Although in the past substantial research has been conducted on FRP strengthened reinforced concrete (RC) beams, but the behavior of FRP strengthened beams under different schemes of strengthening is not well established. In the present paper, efficiency and effectiveness of different but very practical FRP schemes for flexure and shear strengthening of RC beams has been studied. For this purpose, 6 RC beams were cast in two groups, each group containing 3 beams. The specimens of first group were designed to be weak in flexure and strong in shear, whereas specimens of second group were designed just in an opposite manner i.e. they were made weak in shear and strong in flexure. In each group, out of the three beams, one beam was taken as a control specimen and the remaining two beams were strengthened using two different Carbon FRP (CFRP) strengthening schemes. All the beams of two groups were tested under similar loading. The response of control and strengthened beams were compared and efficiency and effectiveness of different schemes were evaluated. It was observed that tension side bonding of CFRP sheets with U-shaped end anchorages is very efficient in flexural strengthening; whereas bonding the inclined CFRP strips to the side faces of reinforced concrete beams are very effective in improving the shear capacity of beams.