Design considerations for steel bridge coatings include exposure environment, aesthetics, application, and cost. Steel bridge coatings must offer protection against corrosion. Current techniques include traditional three-coat zinc, epoxy, urethane systems, galvanizing, and thermal spray metallization. Another pathway for steel protection includes the use of decades-old inorganic zinc spray-applied coatings. This approach offers the performance of a metallized coating while using conventional spray application. What's new is the use of an inorganic topcoat that maintains performance and shop throughput while adding color and aesthetics. This study will compare a two-coat inorganic coating system alongside galvanized, thermal spray metallizing, and sealed thermal spray metallizing systems in corrosion resistance lab testing. A discussion of applied cost and throughput will be presented, along with a review of the chemistry of this approach and the sustainability benefits it offers.
Mar 19, 2025
