Load-bearing capacity of corroded, patched and FRP-repaired RC beams

This paper presents the results of an experimental study conducted to investigate the performance of corroded, patched and fibre reinforced polymer (FRP) repaired reinforced concrete (RC) beams. The overall programme tested 20 quasi-full-scale (153×254×3000 mm) RC beams of which 17 were corroded under various levels of sustained loads. After corrosion, eight beams were patch-repaired whilst four were FRP-repaired. Two of the patch-repaired beams were later further repaired with FRPs. The test results showed that 1% mass loss of steel reduced the load-bearing capacity of RC beams by 0·8%. Patch repairs were found to slightly increase (by 2·5%) the load-bearing capacity of corroded beams, but to significantly increase their stiffness. The load-bearing capacity of FRP-repaired beams was about 50% larger than the capacity of an uncorroded beam and was insensitive to levels of steel corrosion and to patch repairs. There was, however, a significant increase in stiffness of the patch- and then the FRP-repaired beams. It is, therefore, recommended that repair of corroded RC structures should entail patching followed by FRP repairs.