Fatigue Strength Prediction of RC Beams Strengthened in Flexure using Prestressed NSM CFRP Strips

摘要

A flexural fatigue strength prediction model of prestressed Near Surface Mounted (NSM) Carbon Fiber Reinforced Polymer (CFRP) strengthened beams has been developed in this paper. The prediction model is based on the degradation of the concrete compressive block and the degradation of the bond between the tension reinforcements, prestressed CFRP and steel reinforcements, and the surrounding concrete during the fatigue life. A parametric study using the developed model was conducted on reinforced concrete (RC) beam strengthened with prestressed NSM-CFRP reinforcement. It was concluded that the degradation of the concrete stress-strain relationship has a minor effect on the ultimate capacity of the beam as compared with the effect of bond breakdown.