Experimental study on deformation recovery and residual strength of FRP RC Beams

Abstract

Many researches on behavior of the structures which were externally strengthened with FRPs have been conducted. However, researches on time-dependent behavior have not been conducted yet. In order to provide improved serviceability to reinforced concrete (RC) members strengthened with FRPs, the behavior of RC structures strengthened with FRPs under sustained loads should be investigated. This paper presents a series of long-term deflection, deformation-recovery and residual strength experiments. For the long-term experiments, three RC beams were fabricated and two of the beams were strengthened with a carbon FRP(CFRP) plate and a glass FRP(GFRP) plate respectively. The beams were placed under sustained load for about 550 days and unloaded. After unloading, static flexural experiments were carried out. As the result, CFRP showed better performance in terms of deflection and strains of rebars and CFRP plate. Moreover, CFRP showed higher deformation recovery and residual strength than the other beams. © Tsinghua University Press, Beijing and Springer-Verlag Berlin Heidelberg 2011.