Response of CFRP-strengthened beams under fatigue with different load amplitudes

Extensive experimental studies have been conducted and proved the efficiency of bonding fibre-reinforced polymers (FRPs) systems on structural elements such as reinforced concrete (RC) beams. However, the scarcity of experimental data on the FRP-structural member durability when subjected to extreme loading conditions is unanimously recognized. This paper presents an experimental project undertaken in order to assess the durability of RC beams strengthened with carbon-fibre-reinforced polymers (CFRPs). Small-scale beams were loaded in fatigue for various numbers of cycles and load conditions and then tested monotonically to failure. CFRP–concrete joint appears to be altered by the fatigue loading without affecting the ultimate capacity of the beams. Load–deflection curves and strain responses provide an insight on the performance of CFRP-strengthened beams subjected to severe loading conditions.