First Bridge Across the Yukon River

Until recently, the Yukon River was a major obstacle in constructing a roadway to the oil-rich North Slope of Alaska. But on October 10, 1975, that obstacle was hurdled when the first bridge across the Yukon was opened to traffic. This new $30,000,000 crossing is located 100 miles northwest of Fairbanks. The remote location, extremely cold climate, and other environmental factors called for unusual design and construction. Twin orthotropic steel box girders support a 30-ft-wide roadway. Later, the bridge will carry two 48-in. crude oil pipelines. The bridge's reinforced concrete piers are secured to bedrock on the river bottom with prestressed rock anchors. Because of the very low ambient temperatures, brittle fracture was an overriding concern. Exceptionally tough A537 steel (pressure vessel steel) was used in all major tension areas of girders. Toughness requirements were so stringent that only Japanese producers would quote on the project.