Prediction of the behavior of RC Beams Strengthened with FRP Plates

Epoxy-bonding a composite plate to the tension face is an effective technique to repair reinforced concrete beams since it increases their strength and rigidity. In this paper, the structural behavior of reinforced concrete beams with fibre reinforced polymer (FRP) plates is studied numerically. For it, a numerical damage model is used in order to predict their strength, stiffness and failure modes observed in experimental tests taking into account the influence of different variables such as the amount of steel reinforcement, the type and amount of external reinforcement, the plate length, etc. The consideration of concrete cracking and the yielding of the steel rebars allows to predict in a realistic way the behavior of the strengthened beams and especially the debonding failure mode. In that sense both end and midspan debond can be represented since the model is able to reproduce the tension stiffening phenomenon.