Experiences with Thermal Spray Zinc Duplex Coatings on Road Bridges
Source abstract
Abstract
Road bridges are typically designed with a 100-year lifetime, so protective coatings with very long durability are desired. Thermal spray zinc (TSZ) duplex coatings have proven to be very durable. The Norwegian Public Roads Administration (NPRA) has specified TSZ duplex coatings for protection of steel bridges since 1965. In this study, the performance of TSZ duplex coatings on 61 steel bridges has been analyzed. Based on corrosivity measurements on five bridges, a corrosivity category was estimated for each bridge in the study. Coating performance was evaluated from pictures taken by the NPRA during routine inspections of the bridges. The results show that very long lifetimes can be achieved with TSZ duplex coatings. There are examples of 50-year old bridges with duplex coatings in good condition. Even in very corrosive environments, more than 40-year old coatings are still in good condition. While there are a few bridges in this study where the coating failed after only about 20 years, the typical coating failures are due to application errors, low paint film thickness and saponification of the paint. Modern bridge designs and improved coating systems are assumed to increase the duplex coating lifetime on bridges even further.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Corrosion Behavior and Inhibition · Concrete Corrosion and Durability · Hydrogen embrittlement and corrosion behaviors in metals
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
SINTEF, P.O. Box 4760 Torgarden, NO-7465 Trondheim, Norway
Norwegian Public Roads Administration, 5008 Bergen, Norway
Zelixir Inc., Toronto, ON M5A4R4, Canada
Funding
Statens vegvesen · International Zinc Association
References (15)
Show source-provided references
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