East Span’s Design Wins Fresh Acclaim
- May 01, 2015
The San Francisco—Oakland Bay Bridge East Span is the recipient of the American Council of Engineering Companies’ 2015 Grand Conceptor Award. The honor was recently announced during the Engineering Excellence Awards Dinner and Gala held in Washington, D.C. Attended by around 600 people, the black-tie event acknowledged the accomplishments of some 170 engineering projects worldwide.
The East Span is the world’s longest single-tower, self-anchored suspension bridge, as well as the current holder of the Guinness World Record for the world’s widest bridge. The span follows in the footsteps of such past Grand Conceptor Award winners as the Wacker Drive/Congress Parkway reconstruction in Chicago; the Kauffman Center for the Performing Arts in Kansas City, Mo.; the Lake Borgne Storm Surge Barrier in New Orleans and the Hoover Dam Bypass. A vital link in the Bay Area’s transportation network, the bridge handles some 300,000 vehicles daily.
The western span had been previously retrofitted, but retrofitting the eastern span, which was severely damaged in the 1989 Loma Prieta earthquake, would have been prohibitively expensive.
A joint venture of T.Y. Lin International and Moffatt & Nichol designed the 2.2-mile-long structure to withstand the maximum credible earthquake that experts say could strike the region during the bridge’s lifetime. One standout seismic safety feature is the design of a 525-foot tall tower with independently-moving steel legs that provide shock absorption. Also of note, the bridge’s 1.2-mile-long, twin-viaduct Skyway incorporates expansion joints that allow sections of the span to move several feet in a temblor.