2018-10-152018-10-151990-5FHWA-OK-90-03Oklahoma Department of Transportation State Planning and Research itemhttps://hdl.handle.net/11244/301841Five coating systems were evaluated for use over corroded structural steel surfaces. The coatings were applied over both clean (non-corroded) steel panels and panels pre-corroded in a salt fog chamber. The coated panels were then exposed for 50 days in the salt fog chamber. Visual observations were made on a daily basis to obtain data on blister size, blister frequency, rust rating, and scribe rating. The coatings tested were: ( 1 ) Freecom, Corroseal FOC 54/55, an epoxy one-coat system, ( 2) DuPont, 25P/Imron, an epoxy base coat with a polyurethane top coat, ( 3 ) Praxis, Prax-Ten, a penetrant base coat and a concentrate top coat of metal alkyl sulfonates, (4) Tenemec, series 135/74, an epoxy base coat with a polyurethane top coat, and ( 5) Black Gold, a hydrocarbon sealer base coat with an aluminum flake top coat in a hydrocarbon and solvent binder. The best performing coating was the one supplied by DuPont. The Tnemec coating also performed well and ranked second. The Praxis coating ranked third. The poorest performing coating was Black Gold. The Corroseal coating performed better than Black Gold on the pre-corroded panels, but disbanded from the clean surfaces before the end of the testing period.41 pages11,000,338 bytesapplication.pdfTechnical ReportCorrosionRustingCoastingsPaintsSteelMaintenancePaintingSand Blasting