Fatigue life prediction of RC beams strengthened with prestressed CFRP under cyclic bending loads

The application of prestressed carbon reinforced polymer (prestressed CFRP) in reinforced concrete (RC) members can improve the mechanical properties of strengthened structures and strengthening efficiency. This paper proposed a semi-empirical prediction formula of fatigue lives of the RC beams strengthened with prestressed CFRP under bending loads. The formula is established based on the fatigue life prediction method of RC beams and fatigue experimental data of non-prestressed CFRP reinforced beams done before. Fatigue effect coefficient of the formula was confirmed by the fatigue experiments of the RC beams strengthened with prestressed carbon fiber laminate (prestressed CFL) under cyclic bending loads. Fatigue lives of the strengthened beams predicted using the formula agreed well with the experimental data.