Treatments with Fracture Mechanics in Debonding of FRP-Strengthened Concrete Beams

External bonding fiber reinforced polymers (FRP) to the tension faces of reinforced concrete (RC) beam as an effective approach of rehabilitation and strengthening of reinforced structures have attracted significant interests of researchers in the past decade. Since the load-carrying capacity of RC beams strengthened with the FRP is dominated by interfacial delaminated failure, the anchorage strength in FRP to concrete bonded joints under shear and the debonding stress transferring behavior at the end parts of flexural concrete members bonded with FRP have been deeply studied. Recently, methods of fracture mechanics have been introduced into analyzing the above issues. Compared with the traditional methods, the analytical models of existing fracture mechanics are reviewed and analyzed. Based on them the debonding bearing capacity of FRP-strengthened RC beams is calculated and the corresponding finite element models are created. These models of fracture mechanics are then evaluated with the finite element results and the experimental data from author’s and the literature. Some conclusions with engineering significance are drawn.