Bond and durability of fusion-bonded epoxy-coated steel bars

Abstract

Fusion-bonded epoxy-coated steel reinforcement is used to enhance the corrosion resistance of concrete structures. However, the effectiveness of epoxy-coating may be compromised due to inadvertent presence of holidays and surface damage. Additionally, the bond strength of epoxy-coated rebars is expected to be less effective than that of uncoated bars and may be further impaired due to prolonged exposure to thermal variations. This research was designed to evaluate the bond strength between FBEC bars and concrete under heat cool cycling exposure. The influence of holidays and coating damage on corrosion resistance of FBEC bars was also investigated.

Results of this research indicated a reduction in the critical bond strength between steel and concrete due to the use of epoxy-coating. The potential measurements demonstrated the need for an appropriate interpretation of results when this technique is used. The corrosion current density measurements indicated no corrosion of FBEC bars.