Title: Bond Strength of Prefabricated Epoxy-Coated Reinforcement

Author(s): Liliana De Anda, Camille Courtier, and Jack P. Moehle

Publication: Structural Journal

Volume: 103

Issue: 2

Appears on pages(s): 226-234

Keywords: bars; bond; epoxy; reinforcement; testing.

DOI: 10.14359/15180

Date: 3/1/2006

Abstract:
Prefabricated epoxy-coated reinforcement is used increasingly in reinforced concrete construction in which high corrosion resistance is required. It is well established that epoxy coating reduces bond strength between reinforcement and concrete, and some tests have found that bond strength decreases as coating thickness increases. For prefabricated epoxy-coated reinforcement, it can be difficult to maintain coating thicknesses within required tolerances 175 to 300 µm. Beam-end tests were carried out on bars withoutt coating, bars with green epoxy coating (203 µm coating thickness),, and prefabricated (gray) epoxy coating (203 to 508 µm coating thickness). Tests showed that epoxy coating reduces bond strength, with similar reductions for green and gray coatings. In some cases, bond strength decreased with increasing coating thickness; however, for the range of thicknesses investigated, the reduction factor of current building codes was found to be conservative.