Abstract:
In order to prevent the premature end-debonding of externally bonded fiber reinforced polymer (FRP) composite used for shear strengthening of reinforced concrete (RC) beams, a novel self-locking anchorage for FRP sheet was developed and a hybrid-anchoring method for FRP U-sheet was proposed, which was bonding the FRP to the surfaces of a beam and anchoring the FRP ends by anchor plates. Five specimens were tested to validate the feasibility of the new method, including two control specimen, one specimen strengthened by externally bonded (EB) U-sheets of carbon fiber reinforced polymer(CFRP) and two specimens strengthened by hybrid-anchored U-sheets. The results show that hybrid anchorage can shift the end-debonding of CFRP to the rupture failure and greatly improve the fiber-strength utilization. It performs much better than the conventional method of externally bonding in the aspects of restraining the propagation of the diagonal crack, improving the strain behavior of steel stirrups and CFRP, and increasing the shear capacity of RC beam.