Debonding failure modes of flexural FRP-strengthened RC beams

Abstract In this paper, different types of debonding failure modes are described. Then, experimental results of four-point bending tests on FRP strengthened RC beams are presented and debonding failure mechanisms of strengthened beams are investigated using analytical and finite element solutions. Reasonable results could be obtained for modelling of debonding failure load of tested beams. Existing international codes and guidelines from organizations such as ACI, fib , ISIS, JSCE, SIA, TR55, etc. are presented and compared with the results from the experiments and calculations. A discrepancy of up to 250% was seen between different codes and guidelines for predicting the debonding load. Furthermore, a new recommendation for debonding control is given.

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