- Author
- Alsheh, D. | Nguyen, T. | Martin, J. W.
- Title
- Adhesion of Fusion-Bonded Epoxy Coating on Steel in Alkaline Solution.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Book or Conf
- Adhesion Society Meeting. February 1994, 209-212 p., 1994
- Keywords
- steels | adhesives | bonding | coatings | epoxy resins | exposure
- Abstract
- Fusion-bonded epoxy coated steel bars (hereinafter called coated rebars) have been used in reinforcing concrete structural members for over 20 years. Recent studies, however, indicate that under severe conditions, coated rebars may prematurely corrode leading to a reduction in the structural integrity of the reinforced concrete members and eventually to cracking and spalling of the concrete. In a neutral electrolyte, the failure of an organic-coated steel containing a defect is generally well understood. The bare substrate at the defect site corrodes and the coating area surrounding the defect delaminates from the substrate via a process called cathodic delamination. However, the degradation of a coated rebar in an alkaline, concrete environment has not beea extensively studied. The primary objective of this study is to quantify adhesion loss of fusion- bonded epoxy coated steel panels containing a defect exposed to an alkaline electrolyte. The adhesion was measured by a 90-degree peel test, which provides a contour map of the bonding strengths as a function of the distance from a defect. The quantitative information on the "wet" adhesion will provide insight in the understanding of the mechanisms of the failure of organic-coated rebars in alkaline environment.