Effect of Small Concrete Cover on the Fatigue Behavior of GFRP Bars and Concrete Bond

The paper deals with the influence of cyclic loading on the bond between glass-fiber-reinforced polymer (GFRP) bars and concrete. The experimental study considers eccentric and centric pullout tests that vary by three different parameters: (1) concrete cover; (2) concrete strength; and (3) maximum load applied during cyclic loading. The results showed that the fatigue life of the bond between the considered GFRP rebars and concrete, with a small cover and low concrete quality, is limited by the occurrence of splitting failure. As the cover increases, the fatigue failure mode becomes a combination of splitting and bar pullout. The mechanical properties of concrete have a positive effect on fatigue life.