VERIFICATION OF EFFECTIVENESS OF EPOXY-COATED REBARS

A two year program was initiated in 1996 to document the condition of epoxy coated rebars in Pennsylvania and New York. The objectives of this program were to i) investigate the field performance of epoxy coated reinforcing steel in select bridge decks in Pennsylvania and New York, ii) determine if ongoing or progressive corrosion and/or a reduction in coating adhesion were occurring, with a 95% confidence level, in more than 3% of the deck area in either state, and iii) define variables associated with exposure conditions, concrete properties, and epoxy coated rebar properties which predict the presence or absence of corrosion and/or adhesion reduction. Results from the study showed that the existing condition of epoxy coated rebars in bridge decks in Pennsylvania and New York was very good. The frequency of occurrence of progressive corrosion was less than 3% in Pennsylvania and at least 3% in New York. Coating adhesion reduction or loss was found to be more prevalent and extensive. Probability distribution analyses showed that more than 50% of epoxy coated rebars in bridge decks in Pennsylvania and New York exhibit some degree of adhesion reduction within 6 to 10 years of placement in concrete. It should be pointed out that, although progressive corrosion must be accompanied by complete adhesion loss, coating adhesion alone was not found to be a good predictor of corrosion condition in this study. Performance of epoxy coated rebars was evaluated with respect to two mechanisms for corrosion initiation and propagation on epoxy coated rebars: failures from coating defects and failure by adhesion reduction. Due to the relatively low average age (10 years) of the sample population the performance of the epoxy coated rebars with respect to either of the failure mechanisms at an acceptable confidence level could not be statistically ascertained.

• Corporate Authors:

  CONCORR, Incorporated

  44633 Guilford Drive, Suite 101
  Ashburn, VA  United States  22011

  Pennsylvania Department of Transportation

  Forum Place, 555 Walnut Street
  Harrisburg, PA  United States  17101-1900

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Sohanghpurwala, A A
  • Scannell, W T
• Publication Date: 1998-11-24

Language

• English

Media Info

• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 97 p.

Subject/Index Terms

• TRT Terms: Adhesion; Bridge decks; Corrosion; Defects; Distributions (Statistics); Epoxy coatings; Failure analysis; Field studies; Performance evaluations; Probability; Reinforcing bars
• Geographic Terms: New York (State); Pennsylvania
• Subject Areas: Bridges and other structures; Data and Information Technology; Design; Geotechnology; Highways; Materials; I24: Design of Bridges and Retaining Walls; I34: Steels and Metals;

Filing Info

• Accession Number: 00765883
• Record Type: Publication
• Report/Paper Numbers: PA-99-0001+94-05,, RP 94-05,, Final Report
• Files: TRIS, USDOT, STATEDOT
• Created Date: Jul 6 1999 12:00AM