Short Span Steel Bridges 
Time to First Maintenance Chart for Hot-Dip Galvanized Coatings
Photo Credit: American Galvanizers Association
The American Galvanizers Association’s Time to First Maintenance Chart provides a visual representation of the approximate time to first maintenance in years for batch hot-dip galvanized steel in atmospheric exposure based on five defined environments and zinc coating thickness.
Additional Details:
The Time to First Maintenance (TFM) Chart was developed from real world data and a corrosion prediction model, the Zinc Coating Life Predictor (ZCLP). The corrosion rate data was collected from galvanized steel samples exposed to the five defined environments in locations around the world and then coupled with the statistical methods and neural network technology of the ZCLP.
The data points of the TFM chart are based on macroscopic environmental data and, thus, may vary from the actual corrosion rate observed, due to site-specific environmental conditions. Atmospheric levels of airborne salinity, precipitation, relative humidity, sulfur dioxide, and temperature influence actual corrosion rates in a specific geographic location. Zinc coating thickness is linearly related (on a macrolevel) to the time to first maintenance of hot-dip galvanized steel.
Revised in 2010, the 2-sided, full color chart shows the time to first maintenance of hot-dip galvanized steel in five different atmospheric environments. The reverse page contains a singled-out view of the industrial environment’s time to first maintenance.
Does the SSSBA offer educational opportunities?
Yes! The SSSBA offers educational opportunities to students and professionals:
Professionals: The SSSBA provides complimentary half-day or full-day workshops on short span steel bridge design to states, counties, and design firms. Topics covered include practical and cost-effective steel bridge design and fabrication with eSPAN140, press-brake-formed steel tub girders, steel buried bridge design, galvanized coating solutions, and economical design with case studies, and more. The workshops can take place virtually or in-person, compliments of the steel industry. Learn more.
Students: The University of Wyoming and the Short Span Steel Bridge Alliance created a free 6-part live-lecture educational series to cover the many aspects of designing, fabricating, and constructing steel bridges. All students who successfully complete the education series will receive a Certificate of Completion from the University of Wyoming. Learn more.
Speakers: The SSSBA provides expert speakers to present topics of interest on the cost-effective design and construction of short span steel bridges. If you need a speaker for your next event, contact the SSSBA.
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