Corrosion Evaluation of Repair-Grouted Post-Tensioned Tendons in Presence of Bleed Water

摘要

Material defects in post-tensioned tendons may lead to corrosion development of the steel strand. It was generally accepted that corrosion development occurs in post-tensioned tendons when void spaces develop in the tendon due to the accumulation of grout bleed water and subsequent evaporation and reabsorption into the grout and exposing strand. Recently, post-tensioned tendon failures have been associated with deficient grout in part caused by grout segregation. Repair of void spaces in those deficient tendons alone without addressing the deficient grout may not necessarily mitigate corrosion development. Corrosion development of steel strand with unmitigated bleed water presence in repair grouted post-tensioned tendons is addressed.