POST-REPAIR PERFORMANCE OF CORROSION-DAMAGED REINFORCED CONCRETE BEAMS REPAIRED WITH FRP SHEETS

摘要

This paper presents an experimental program that investigated the short-term and the post-repair performance of relatively large-scale corroded reinforced concrete beams repaired with FRP sheets. Ten reinforced concrete beam specimens (152x254x3200mm) were constructed. One of the specimens served as control, while the other nine specimens were chloride-contaminated by premixing 2% chlorides by weight of cement in the bottom third of each specimen along the middle 1400mm of the specimen length. These nine specimens were exposed to a minor corrosion degree (5.5% mass loss) by impressing a current through the main longitudinal rebars. After being corroded, six specimens were repaired with FRP sheets using two different schemes. One scheme included wrapping the specimen with U-shaped GFRP sheets. The other scheme included flexural strengthening of the specimen with CFRP sheets followed by wrapping the specimen identically to the first scheme using U-shaped GFRP sheets. The control specimen and three corroded unrepaired specimens with different corrosion degrees (5.5%, 9%, and 12.5% mass loss) were tested under four-point bending till failure. Two corroded repaired specimens (5.5% mass loss) were tested till failure directly after the repair process to examine the short-term performance of the repaired specimens. The other four repaired specimens were exposed further to higher corrosion degrees (9% and 12.5 % mass loss) and then tested to failure to examine their post-repair performance.