Bond Durability Factor for Externally Bonded CFRP Systems in Concrete Structures

Abstract

Lack of understanding and confidence in the long-term performance of externally bonded fiber-reinforced polymer (FRP) composites in concrete structures still inhibits their application in repair of aged structures. While synergistic effects of multiple exposure conditions can be severe, it is generally agreed that the single most significant issue with externally bonded FRP composites is their susceptibility to degradation when exposed to moisture. This research utilized small-beam three-point bending test specimens to study FRP–concrete bond performance when subjected to accelerated conditioning environments (immersion in water and exposure to high humidity at elevated temperatures). Bond strength retention (