Simulation of concrete cover separation failure in FRP plated RC beams

The flexural strength of a reinforced concrete beam can be increased by bonding a FRP sheet to the tension face. Nevertheless, this type of reinforcement may cause a premature debonding failure. This paper is concerned with the failure by concrete cover separation; in other words by peeling-off. Four series of FRP plated RC beams and one group of control beams were tested in a four-point bending setup where each group consisted of three beams. All strengthened beams failed by peeling-off. As a part of this study numerical analyses using the commercial program; Abaqus have been carried out in order to predict this type of failure. Comparisons between the predictions of the numerical model and test results show a very good agreement indicating that the ultimate load, the beam behavior and the failure mode can be closely predicted by using the proposed model.

► This study presents test results of 12 FRP strengthened RC beams and 3 control beams. ► Strengthened beams exhibited higher load capacity, lower ductility than reference beams. ► All strengthened beams failed by concrete cover separation which is a brittle failure. ► Numerical results also predict peeling-off failure for all strengthened beams. ► The thicker the FRP sheets, the higher the stiffness is and the lower the load capacity is.