Title: Bonding and Corrosion Protection Properties of Two Coatings for Prestressing Steels
Author(s): Fernand Ellyin and Rafik A. Matta
Publication: Journal Proceedings
Appears on pages(s): 366-371
Keywords: beams (supports); bonding; calcium chloride; coatings; corrosion;
cracking (fracturing); deicers; epoxy resins; flexural tests; friction; post-ten-sioning;prestressed concrete; prestressing steels; protective coatings; pullouttests; salts; slurries.
Corrosion resistance and bonding properties of two types of coatings have been investigated. Cement slurry and coal-tar modified epoxy (resin) were applied on different types of prestressing steels. Twenty pretensioned and post-tensioned beams with uncoated, cement-slurried, and resin-coated strands were subjected to the attack of calcium chloride (CaClJ and sulfur dioxide (SO*) environments. The results indicated that both coatings protected the prestressing steels against corrosion; however, provisions have to be made concerning the bonding properties of these coatings. It is concluded that in the case of coated pretensioned strands, care must be exercised to insure a sufficient transfer length. This will then allow for the development of the required ultimate moment of resistance.