Effects of temperature on the behaviour of fiber reinforced polymer reinforced concrete members: experimental studies

Thermal characteristics of fiber reinforced polymer (FRP) reinforcement can be substantially different from those of concrete and conventional steel r einforcement. The influence of this difference on the behaviour of FRP rein forced concrete members is studied in this paper. Concrete beams reinforced with different types of FRP rebars are tested under the effects of tempera ture gradient while the rotation at the two ends of the beam are restrained . The bending moments and cracking developed by the thermal gradient are mo nitored. The results are compared with those obtained from tests on beams o f the same dimensions but reinforced with steel bars. The behaviour of ther mally cracked members is also investigated under mechanical load effects at both service and ultimate load levels. The potential cracking of the concr ete cover caused by the transverse thermal expansion of FRP bars is examine d by testing concrete cylinders. The experiments show the difference in the rmal behaviour of glass and carbon FRP and steel bars.