Experimental study of FRP-strengthened concrete beams with corroded reinforcement

Corrosion of steel reinforcement is the major cause deterioration in reinforced concrete structures. Strengthening structures has been widely studied. However, most research was conducted on sound without considering effects corrosion. This paper presents an experimental study feasibility using externally bonded FRP laminates combined with U-jackets, applied directly repairing deteriorated cover, to strengthen beams corroded reinforcement. Ten were tested four-point bending. Two not and non-strengthened; these served as references. The other eight pre-loaded induce flexural cracks then exposed accelerated strengthened, three strengthened glass-FRP (GFRP) carbon-FRP (CFRP) plates beam soffits. On six beams, CFRP U-jackets installed along span. Local corrosion levels evaluated a 3D-scanning technique. Pitting significantly reduced load-carrying deformation capacity beams. Despite average 20%, local up 57% corrosion-induced 1.9 mm wide, FRP-strengthening method (applied cover) effective upgrading stiffness. effectively suppressed delamination cover led rupture GFRP utilisation ratio 64%. improvement noticeable; this requires further research.