Shear peeling of steel plates bonded to tension faces of RC beams

The technique of adhesively bonding steel or fiber-reinforced plastic plate s to the surfaces of reinforced concrete (RC) structural elements is being adopted worldwide to strengthen or repair reinforced concrete buildings and bridges. However, the prevention of premature debonding or peeling of exte rnally bonded plates is a most critical aspect of design. One of the major modes of debonding in plated RC beams is shear peeling induced by the forma tion of critical diagonal cracks caused by the applied vertical shear force s. In this paper, mathematical models are developed for quantifying the she ar peeling resistance of RC beams bonded with plates of different configura tions. These models are based on the simplified theory of plasticity concep ts for shear in reinforced concrete beams and also on procedures to compute the bond strength between an adhesively bonded plate and a concrete elemen t. The models are validated against 32 test results from reinforced concret e beams adhesively bonded with either steel plates or steel angles attached to the tension faces, or tension face plated beams additionally bonded wit h side plates to improve their shear peeling resistance.