The Detection and Remediation of Total Soluble Salt Contamination Prior to Coating Structural Steel

Bridge steel protective coatings typically fail in localized areas of a bridge. The failed areas normally comprise less than 5 percent of the coated surface area. Identification and remediation of soluble salts (chlorides, sulfates, and nitrates) could greatly extend the service life of protective coatings by eliminating those areas of premature coatings failure. Current test methods are not effective in evaluating problematic soluble salt levels in bridge steel when the soluble salts are concentrated randomly (i.e., in pits). This may allow retention of high localized concentrations that will promote premature failure in subsequent coating applications. A second issue is the identification of practical, effective methods for surface preparation of existing bridge steel substrates to minimize or eliminate these localized "hot spots" prior to coating application. Studies have shown that pressure washing, abrasive blasting, or a combination of the two are not effective in removing soluble salt "hot spots." Effective soluble salt contamination identification and remediation is essential to maximizing the life of structural steel maintenance coatings. This research supports the performance management and research strategic focus areas of the Subcommittee on Maintenance, Bridge Technical Working Group. The objective of this research is to develop methods to identify and remediate total soluble salt contamination prior to coating structural steel. Accomplishing these objectives will require the following tasks: (1) Identify and quantify existing methods for the location/‌distribution of soluble salts on steel. (2) Develop new methods for identifying the location/‌distribution of soluble salts on steel surfaces. (3) Identify effective soluble salt remediation method(s). (4) Develop training for bridge owners in the identification and remediation of soluble salts in order to achieve accurate field use of the methods.


  • English


  • Status: Proposed
  • Contract Numbers:

    Project 10-97

  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway & Transportation Officials

    444 North Capitol Street, NW, Suite 225
    Washington, DC  United States  20001

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Harrigan, Edward

  • Start Date: 20141111
  • Expected Completion Date: 0
  • Actual Completion Date: 0
  • Source Data: RiP Project 37556

Subject/Index Terms

Filing Info

  • Accession Number: 01543351
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 10-97
  • Files: TRB, RiP
  • Created Date: Nov 13 2014 1:01AM