Longest U.S. suspension span in 40 years heads toward completion
Construction of the new Tacoma Narrows Bridge just south of Seattle, Washington, reached its final major milestone in January 2007, when the last remaining section of deck was hoisted into place.
The bridge, which will cross over the narrows to connect Tacoma and Gig Harbor, is the longest suspension span built in the United States in four decades. Designed and built by a joint venture of Bechtel and Kiewit Pacific, it is scheduled to open later this year.
The new bridge is adjacent to bridge built in the 1950s, which replaced a bridge that was destroyed in a 1940 windstorm. The collapse of the earlier bridge, nicknamed “Galloping Gertie,” was captured on film, and the event changed the way suspension bridges were designed.
The project to build the new Tacoma Narrows Bridge began late in 2002, by which time 90,000 cars a day were crossing the existing bridge, which was designed to handle 60,000.
Major construction work on the new bridge included installing caissons for a pair of 165-meter-tall towers, building the towers, spinning cables, and assembling the deck. During the final phase, 46 deck sections—each weighing some 450 tons—were lifted and attached to suspension cables.
Manuel Rondon, project manager for the joint venture, called the completion of the deck lifts a welcome landmark in what has been a successful project.
Remaining work includes bolting and welding the sections together, preparing and paving the deck surface, and installing pedestrian railings. When complete, the deck will stretch 1,646 meters from end to end, and the main span will be 854 meters from tower to tower.
The new Tacoma Narrows Bridge will carry eastbound traffic, while the existing parallel bridge goes westbound.
The bridge, which will cross over the narrows to connect Tacoma and Gig Harbor, is the longest suspension span built in the United States in four decades. Designed and built by a joint venture of Bechtel and Kiewit Pacific, it is scheduled to open later this year.
The new bridge is adjacent to bridge built in the 1950s, which replaced a bridge that was destroyed in a 1940 windstorm. The collapse of the earlier bridge, nicknamed “Galloping Gertie,” was captured on film, and the event changed the way suspension bridges were designed.
The project to build the new Tacoma Narrows Bridge began late in 2002, by which time 90,000 cars a day were crossing the existing bridge, which was designed to handle 60,000.
Major construction work on the new bridge included installing caissons for a pair of 165-meter-tall towers, building the towers, spinning cables, and assembling the deck. During the final phase, 46 deck sections—each weighing some 450 tons—were lifted and attached to suspension cables.
Manuel Rondon, project manager for the joint venture, called the completion of the deck lifts a welcome landmark in what has been a successful project.
Remaining work includes bolting and welding the sections together, preparing and paving the deck surface, and installing pedestrian railings. When complete, the deck will stretch 1,646 meters from end to end, and the main span will be 854 meters from tower to tower.
The new Tacoma Narrows Bridge will carry eastbound traffic, while the existing parallel bridge goes westbound.
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