Calcium magnesium acetate (CMA) has been selected in Federal Highway Administration sponsored research as being among the most viable salt (NaCl) subsitutes for highway deicing. This study documents the corrosiveness of a water solution of CMA compared with that of an equivalent (for deicing purposes) concentration of NaCl in water, in identical exposure environments for the major structural metals currently used in Michigan's highway system. Additional work with most of the same structural metals has been performed in distilled water alone, simulated acid rain, a commercially available rust inhibitor with MgCl2, the same rust inhibitor with NaCl, and CMA and CaCl mixtures (CMA/NaCl weight ratios of 1.75, 0.46, 0.11, and 0.03 with NaCl concentration held at 3.5%). Electroslag and submerged arc welds (representing the major weld chemistries used on Michigan's structures) in weathering steel (ASTM A588) were also exposed to CMA and NaCl solutions. Results are reported in detail for structural (bridge) steels, steel bar reinforcement for concrete, steel prestressing strand for concrete, some aluminum alloys, galvanizing, and some galvanic couples. Performance is rated by average corrosion, maximum pit depth, crevice corrosion, maximum crevice pit depth, and loss of tensile strength (effective cross-sectional area reduction).

  • Corporate Authors:

    Michigan Department of Transportation

    State Transportation Building, 425 West Ottawa Street, P.O. Box 30050
    Lansing, MI  United States  48909
  • Authors:
    • McCrum, R L
  • Publication Date: 1988-12

Media Info

  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 74 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00621709
  • Record Type: Publication
  • Report/Paper Numbers: Res Rept No. R-1295, Res Proj 82 G-259
  • Created Date: Apr 30 1992 12:00AM