Residual Strength and Deformation Recovery of RC Beams Strengthened with FRPs Plates under the Sustained Load

Abstract

In this paper, in order to estimate efficacy, creep recovery, and residual strength of Fiber Reinforced Polymers (FRPs) strengthened Reinforced Concrete (RC) beams, long-term flexural experiments and static flexural experiments were carried out. For the long-term experiments, the beams were strengthened with a Carbon Fiber Reinforced Polymer (CFRP) plate and a Glass Fiber Reinforced Polymer (GFRP) plate respectively. The beams were placed under sustained loads for about 550 days. After the 550 days, all of the beams were unloaded for the measurement of deformation recovery. The deflection and strains of rebars and FRPs reinforcements were measures for about 60 days. As the result of long-terms experiment, the beams strengthened with CFRP plate showed a better performance in terms of deflection and strains of rebars. And the strengthened RC beams were very effective in terms of deflection control. Furthermore, the strengthened beams have shown immediate deformation recovery. Through the static flexural experiments, it was shown that the CFRP strengthened beam had high residual strength. It seems that the sustained loads did not affect bond and residual strength of the beams.