ABSTRACT

Bonding fibre-reinforced polymers (FRP) to reinforced concrete (RC) members has become a popular means for enhancing load carrying capacity and extending service life of bridge structures. However, there is uncertainty surrounding the long-term durability of flexurally strengthened members. This paper presents work on an experimental program to determine the debonding resistance of FRP-to-concrete interface considering environmental conditions and material durability. Further a mechanics based model that considers the intermediate-crack (IC) debonding behavior at the FRP-concrete interface as both a l ocal and global mechanism along the length of a beam is also presented. The model is shown to be able to accurately predict the load-deflection response of FRP-strengthened beams considering the bond properties at the FRP-to-concrete interface.