Interface slip effect on bonded plate repairs of concrete beams

Severe aging and deterioration of the transportation infrastructure has motivated extensive research in developing structural repair techniques using FRP or steel plates. As a result, previous researchers have developed several analytical methods to predict the interface performance of bonded repairs, but most of them are quite complicated and are thus not convenient for routine applications. The present study has developed a relatively simple procedure to predict the interfacial performance of two bonded solid bodies using a simple beam theory and equilibrium conditions. It explicitly considers the interface slip effect on the structural performance. The results agree reasonably well with those from more complicated theories, finite element predictions and test measurements. Simplifications are proposed that do not sacrifice accuracy for beams of common proportions. A parametric study has been conducted to investigate the sensitivity of interface behaviours to parameters such as the interface layer stiffness and loading position. An example demonstrates the convenience of the method for the design of retrofits or repairs.