Behaviour of corrosion damaged reinforced concrete beams strengthened using CFRP laminates

Abstract

This paper presents experimental results on the behaviour of corrosion damaged reinforced concrete beams repaired using a cementitious patch repair material and strengthened using carbon fiber reinforce polymer (CFRP) plates. Four RC beams (154 mm × 254 mm × 5000 mm long) were used. Three of the beams were subjected to different levels of accelerated corrosion (using an impressed anodic current and 5% NaCl solution) under sustained service loads while one beam acted as a control. The service load was estimated as 80% of cracking moment. The three corrosion-damaged beams were using a repair mortar; further, two of the patch-repaired beams were strengthened with carbon fibre reinforced polymer (CFRP) laminates. The effect of damage on the stiffness of the beams was inferred from natural frequencies, strain measurements and deflection measurements. The effect of patch repair and strengthening on corrosion damaged beams was deduced from the changes in their ultimate capacities. The results reveal that the stiffness and the ultimate capacity are improved by about 25% and 50% respectively when both patch repair and CFRP are applied on a damaged beam. Patch repair only, improved the stiffness by approximately 5% but did not improve the ultimate capacity. © RILEM 2013.