Premature failures in the concrete beams strengthening with FRP plates, introduce various models and compared the theoretical and experimental result

External bonding of composite plates for strengthening and increase the flexural capacity of reinforced concrete beams has been widely popular. To determine the ultimate capacity should be realize the debonding phenomenon in the interface. This paper includes two parts. The first explained the phenomenon of premature failures، detailed of plate separation and introduce the theoretical models. In the second part، the experimental results obtained by researcher''s compare with the model provided by author to determine the accuracy of predict premature failure load.