Behavioral trends of RC beams strengthened with externally bonded FRP

Abstract

The performance of conventionally reinforced concrete (RC) beams strengthened in flexure with externally bonded fiber-reinforced polymers (EB-FRP) was studied by compiling and analyzing an experimental database. A total of 127 specimens from 23 separate studies were included in the database. A profile of specimens in the database is given, followed by an analysis of trends in failure mode, strength gain, and deformability. Failure by debonding of FRP was prevalent among specimens in the database. One-third of the specimens with external reinforcement added showed strength increases of 50% or more in combination with considerable deflection capacity. It was clear from the experimental studies that the procedures followed were most representative of member strengthening rather than repair. Most of the specimens in the database were not subjected to sustained loading or damage causing loss of original capacity before external reinforcement was added. To assess the real potential of using FRP for expedient and economical field repair and strengthening of RC members, it was concluded that future research on the application of FRP to RC members should focus on conditions that are similar to what is observed in the field, including the effects of sustained load during repair/strengthening as well as corrosion- and load-induced damage.