STRENGTHENING OF RC BEAMS WITH EXTERNAL FRP TENDONS: TENDON STRESS AT ULTIMATE

摘要

FRP tendons exhibit a wide range of elastic modulus, with most of them less than that of steel prestressing tendons. In this paper, an attempt is made to incorporate the elastic modulus of FRP tendons in the predictive equation for unbonded tendon stress specified in ACI Building Code. This is followed by a parametric study on the flexural strengthening of a deficient continuous beam with different types of FRP tendons. In general, a lower elastic modulus of the tendon results in lower tendon stress increment, especially when a larger effective tendon depth is used, thereby reducing the ultimate load-carrying capacity and strengthening ratio for the beam.