Abstract
To establish a rational flexural reinforcing method for existing Reinforced Concrete (RC) beams using pretensioned Aramid Fiber Reinforced Polymer (AFRP) sheet, static loading tests on flexural reinforced RC beams were conducted taking sectional shape of beam, rebar ratio, sheet volume ratio, shear span ratio, and pretension force ratio as variables. In this study, the effects of these parameters on load-carrying capacity of the beams and debonding behavior of the sheet were investigated by comparing with between experimental results and analytical ones calculated by means of the multi section method. Furthermore, empirical prediction equations for failure mode of the RC beams reinforced with pretensioned AFRP sheet were developed. From this study, following results were obtained: 1) applying the pretensioned AFRP sheet bonding method proposed here, the load-carrying capacity of the RC beams can be upgraded irrespective of the magnitudes of design parameters of the RC beam; 2) introducing the pretension force to the AFRP sheet, sheet debonding due to peeling action of the critical diagonal cracks can be more restrained; and 3) an empirical prediction equation for failure mode of the flexural reinforced RC beam with pretensioned AFRP sheet was proposed which is composed of calculated two bending moments at rebar yielding and the ultimate state.
