Add to ORKGThe paper describes an experimental program for studying the fatigue performance of GFRP bars, which has been initiated by the authors. Two different test configurations were used to assess the fatigue behaviour. The bare specimens were tested within the first series. A modified gripping system was used to reduce eccentricity when the bar was not directly fixed. However, the boundary conditions seem to affect the results. The second series consisted of a set of specimens of bars embedded in concrete. This configuration seems appropriate for determination of fatigue life of GFRP bars. Two S-N curves for bare bars and bars embedded in concrete were created and compared. Significant reduction of interlaminar shear strength at the beginning of ...