AN INVESTIGATION OF DURABLE COATING SYSTEMS FOR MAINTENANCE PAINTING OF THE SKYWAY STRUCTURAL STEEL BRIDGES
In order to specify more durable protective coatings for high level (Skyway) structural steel bridges, two paint systems were evaluated by the laboratory. One paint system was based on proprietary universal primer with high build vinyl topcoat and the other system was based on inorganic zinc silicate with high build vinyl topcoat. Comparative laboratory salt spray resistance and accelerated weathering durability tests as well as chemical and physicl analyses of the paint systems were performed. Field sandblasting of the existing painted bridge structures and trial application of small test patches of universal primer were also carried out to determine the effects of sandblasing of old paint and reaction between different paint systems. Based on salt spray corrosion resistance and accelerated weathering tests, the universal primer/vinyl paint system applied over sound existing alkyd bridge paint was not satisfactory due to reaction between the old and new paint systems which caused lifting and flaking of all paint and rusting of the steel substrate. The inorganic zinc/vinyl paint system applied over near-white sandblasting steel surface was found to be more durable than the alkyd paint system previously applied on the skyway structures. The better quality inorganic zinc/vinyl paint systems were considered to be more than twice as durable as the alkyd paint system.
Ontario Ministry of Transportation & Communic, CanEngineering Materials Office, 1201 Wilson Avenue
Downsview, ONo M3M 1J8, Canada
- Fujii, R Y
- Publication Date: 1980-8
- Features: Figures; References; Tables;
- Pagination: 45 p.
- TRT Terms: Alkyd resins; Alternatives analysis; Chemical reactions; Durability; Metal bridges; Paint; Protective coatings; Salt fog tests; Silicates; Steel bridges; Structural steel; Vinyl resins; Weathering; Zinc
- Old TRIS Terms: Paint system; Resistance
- Subject Areas: Bridges and other structures; Geotechnology; Highways; Materials; I34: Steels and Metals;
- Accession Number: 00335515
- Record Type: Publication
- Report/Paper Numbers: EM-40
- Files: TRIS
- Created Date: Nov 23 1981 12:00AM