Flexural behavior of corroded pretensioned girders repaired with CFRP sheets

This paper presents a study that assessed the effect of corrosion of seven-wire steel strands on the residual capacity of pretensioned concrete T beams subjected to static flexural loading and the viability of carbon-fiber-reinforced polymer (CFRP) repair in restoring the original capacity. The experimental program comprised testing six 3.6 m [12 ft] pretensioned concrete T beams, each having 400 mm (16 in.) flange width, 300 mm (12 in.) total height, and 100 mm (4 in.) web thickness. The experimental variables were the mass loss due to corrosion (0%, 2.5%, 5%, and 10%) and the repair condition (unrepaired and repaired beams using adhesively bonded CFRP sheets). Test results showed a reduction in flexure capacity and midspan deflection of up to 76% and 26%, respectively, at 10% mass loss. CFRP repair was able to restore the load capacity to that of the uncorroded beams; however, the reduction in ductility due to corrosion was not reversible.