Role of U-shaped anchorages on performance of RC beams strengthened by CFRP plates

Use of Carbon Fiber Reinforced Polymer (CFRP) Plates, as externally bonded reinforcement, is a practically efficient and technically sound method of strengthening and upgrading structurally inadequate or otherwise damaged or deteriorating Reinforced Concrete (RC) members. The ultimate capacity of the strengthened beam is controlled by either compression crushing of concrete, rupture of the composite plate, local failure of concrete at the plate end due to stress concentrations and flexural shear crack-induced debonding of Concrete-CFRP interface. Another factor that could affect the ultimate strength and mode of failure is the shear span. Beams with U-shaped anchorages were tested in four-point bending to determine the ultimate load carrying capacities and modes of failure of the beams. Properly placed U-shaped anchorages at plate cut-off points and along the span were shown to be effective in improving the performance of CFRP strengthened RC beams in flexure and shear by optimizing deformability and strength characteristics.