NBS FINDS WAY TO REDUCE U.S. HIGHWAY REPAIR COSTS

EPOXY COATINGS APPLIED AS POWDERS BY AN ELECTROSTATIC SPRAY TECHNIQUE PROVIDE THE BEST PROTECTION (BOTH CHEMICAL AND MECHANICAL) FOR STEEL REINFORCING BARS WHICH CORRODE IN CONTACT WITH THE CHLORIDE IONS CONTAINED IN SUCH ROAD DEICING CHEMICALS AS SODIUM CHLORIDE AND CALCIUM CHLORIDE. EPOXY COATINGS OFFER BETTER FILM INTEGRITIES, FEWER FILM DEFECTS AND GREATER FLEXIBILITY THAN LIQUID EPOXIES. AN INVESTIGATION TEAM SELECTED AND APPLIED 47 COMMERCIALLY AVAILABLE ORGANIC COATING SYSTEMS, EVALUATED THEIR PROTECTIVE QUALITIES IN A PORTLAND-CEMENT CONCRETE-CHLORIDE ENVIRONMENT AND STUDIED THE MECHANICAL CHARACTERISTICS OF THE COATED BARS IN BRIDGE DECKS. THE BOND STRENGTH BETWEEN COATED REBARS AND CONCRETE WAS CAREFULLY DETERMINED. THE EVALUATIORY PROGRAM IS TABULATED. ON THE BASIS OF THESE STUDIES, IT WAS CONCLUDED THAT CORRECTLY FORMULATED AND APPLIED EPOXY OF 7 MIL THICKNESS HAS ADEQUATE FLEXIBILITY AND PROTECTIVE VALUE FOR USE ON CONCRETE REINFORCING BARS. THE FHWA IS ENCOURAGING ITS IMPLEMENTATION DIVISION AND STATE HIGHWAY DEPARTMENTS TO DESIGN AND BUILD BRIDGE DECKS EMBODYING THE TEST FINDINGS. THE USE OF THESE EPOXY COATINGS WILL HELP REDUCE THE ANNUAL REPAIR COSTS NECESSITATED BY THE PREMATURE DETERIORATION OF CONCRETE HIGHWAY BRIDGE DECKINGS.

  • Corporate Authors:

    National Bureau of Standards

    Department of Commerce, Office of Technical Publications
    Washington, DC  USA  20234
  • Publication Date: 1973-7

Media Info

  • Features: Figures; Photos; Tables;
  • Pagination: p. 168-9
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00214300
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jun 26 1974 12:00AM