Experimental Study on the Static and Fatigue Performance of Corroded RC Beams Strengthened with AFRP Sheets

In order to research the strengthening effects of aramid fiber reinforced polymer (AFRP) sheets on the flexural performance of corroded reinforced concrete (RC) beams, the static and fatigue performance of corroded RC beams strengthened with non-prestressed AFRP sheets under different degrees of corrosion (minor: reinforcement mass loss is 2.0%, medium: reinforcement mass loss is 6.0%) have been researched experimentally in this paper, to compare with that of the control beams (un-strengthened and un-corroded) and un-strengthened corroded beams, and additionally compare with fatigue performance of those medium corroded RC beams strengthened with prestressed AFRP sheets with permanent anchors. The results show that, (1) compared with un-strengthened corroded beams under the same degrees of corrosion, the cracking, yield and ultimate monotonic loads of the minor corroded RC beam strengthened with non-prestressed AFRP sheets is respectively increased by 20%, 27% and 60%, whereas for the medium corroded RC beam strengthened with non-prestressed AFRP sheets increased by 15%, 36% and 83% respectively. The ultimate deflection of the medium corroded beam strengthened with non-prestressed AFRP sheets is 166% larger than that of the corroded un-strengthened beam under the monotonic load. (2) The fatigue life of the non-prestressed AFRP strengthened medium corroded beam is 10.4 times more than that of the un-strengthened corroded beam, but lower than that of the unstrengthened-uncorroded (virgin) beam. (3) Fatigue experiments of the beams strengthened with prestressed AFRP sheets and with those non-prestressed AFRP sheets show that the fatigue life of the retrofit RC beams increase with increasing prestress level of AFRP sheets.(4) The use of AFRP sheets for strengthening corroded RC beams is an efficient technique that can maintain the structural integrity and enhance the structural behavior of such beams.