BRIDGE PAINTS WITH RESISTANCE TO SALT BRINE

A VERY SEVERE PAINT TEST EXPOSURE IS REPORTED WHICH WAS INITIATED, COMBINING THE EFFECTS OF SALT SPRAY WITH TYPICAL ATMOSPHERIC EXPOSURE. THE SITES SELECTED CONSISTED OF THE STEEL FLOOR BEAM SECTIONS ON TWO RAILROAD BRIDGES ON THE MISSOURI PACIFIC RAILROAD, NEAR ST. LOUIS, REPRESENTING AREAS WHICH ARE SUBJECTED SEVERAL TIMES PER DAY TO THE SALT SPRAY FROM THE DRIPPINGS OF PASSING REFRIGERATOR CARS. THIS STUDY WAS INITIATED BECAUSE FOR MANY YEARS SALT BRINE HAS BEEN ONE ON THE MOST SERIOUS CAUSES OF CORROSION OF STEEL BRIDGES, BOTH ON THE HIGHWAYS AND THE RAILROADS. THE LATEST INSPECTION REVEALED THE IMPORTANCE OF GOOD SURFACE PREPARATION BY BLAST CLEANING, PARTICULARLY AS A BASIS FOR THE MOST EFFECTIVE COATINGS SYSTEMS, WHICH ARE VINYLS, CHLORINATED RUBBERS AND CERTAIN PHENOLIC-ALKYD COMBINATIONS. THE NEXT MOST EFFECTIVE SYSTEMS ARE STYRENE-BUTADIENE, CONVENTIAL OIL BASE PAINTS, COAL TAR MASTIC, AND ASPHALT MASTIC. WASH PRIMERS WERE HELPFUL ON THE SEVERELY-EXPOSED SECTIONS WITH SEVERAL OF THESE SYSTEMS. A NUMBER OF OTHER SYSTEMS WERE VERY EFFECTIVE ON AREAS EXPOSED TO THE LESS SEVERE DRIPPINGS, INCLUDING A ZINK DUST PAINT, CERTAIN TAPES, TWO VINYL MASTICS AND A URETHANE. SAND BLASTING WAS SHOWN TO BE DEFINITELY SUPERIOR TO CAREFUL HAND CLEANING. THE FOLLOWING SEVERAL DIFFERENT KINDS OF PAINTS SYSTEMS GAVE ALMOST EQUALLY GOOD PROTECTION OVER CAREFULLY BLAST CLEANED STEEL: VINLYS, CHLORINATED RUBBER AND CERTAIN PHENOLICS AND COMBINATIONS OF ALKYD PRIMERS WITH PHENOLIC TOP COATS. A NUMBER OF OTHER COATING SYSTEMS SHOWS GOOD PERFORMANCE BUT NOT EQUAL TO THE PREVIOUS ONES, INCLUDING: STYRENE- BUTADIENE, CONVENTIONAL OIL BASE SYSTEMS WITH RED PRIMER AND GRAPHITE TOPCOAT, COAL TAR MASTIC, AND ASPHALT MASTIC OVER PHENOLIC PRIMER.

• Supplemental Notes:
  • pp 1-17, 1 FIG, 2 TABS
• Corporate Authors:

  Steel Structures Painting Council

  4400 Fifth Avenue
  Pittsburgh, PA  United States  15213
• Authors:
  • Keane, J D
• Publication Date: 1968

Subject/Index Terms

• TRT Terms: Alkyd resins; Blast cleaning; Bridge decks; Butadiene; Chlorination; Coal tars; Corrosion resistance; Crash exposure; Graphite; Mastic asphalt; Metal bridges; Paint; Phenol; Primers; Protective coatings; Railroad bridges; Rubber; Salt fog tests; Steel bridges; Styrenes; Testing; Vinyl resins
• Uncontrolled Terms: Exposure
• Old TRIS Terms: Mastics
• Subject Areas: Geotechnology; Highways; Maintenance and Preservation; Materials; Safety and Human Factors;

Filing Info

• Accession Number: 00216396
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 8 1994 12:00AM