Plate end debonding in FRP-plated RC beams—II: Strength model

Abstract

RC beams strengthened in flexure by bonding an FRP or steel plate to the tension face can fail by debonding at or near the plate end in a number of different modes. This paper presents a simple, rationally-based predictive model for such plate end debonding failures. In this model, pure flexural debonding for a plate end located in a pure bending region and pure shear debonding for a plate end located in a high-shear zero (or low)-moment region are first dealt with. The general case of a plate end under the combined action of shear and bending is treated as the interaction of these two extreme conditions. The proposed model is shown to be accurate through comparisons with available test results. The model relates the debonding failure load to the shear capacity of the beam and a number of well-defined parameters, and can be easily incorporated in any national or international design codes and guidelines.