September 04, 2015
San Francisco-Oakland Bay Bridge New East Span Wins 2015 Project of the Year from the American Public Works Association
T.Y. Lin International (TYLI), a globally recognized full-service infrastructure consulting firm, announces that the San Francisco-Oakland Bay Bridge New East Span (East Span) has won the American Public Works Association (APWA) 2015 Project of the Year in the Transportation category (cost > $75 million). The APWA Public Works Project of the Year awards recognize the successful alliance between a project’s managing agency, the consultant/engineering firm, the contractor, and their cooperative achievements.
TYLI, in a joint venture with Moffatt & Nichol, served as Engineer of Record on the immense seismic replacement project. Working closely with the California Department of Transportation, the Metropolitan Transportation Commission, and the California Transportation Commission, TYLI engineers were charged with designing a Lifeline Structure that must be operational for emergency traffic shortly after the largest anticipated earthquake.
The 2.2-mile-long East Span, which opened to traffic on September 2, 2013, includes four distinct yet interrelated components: the world’s longest, single-tower Self-Anchored Suspension Span (SAS); the twin Skyway viaducts that ascend to the SAS from the Oakland shoreline; the Oakland Touchdown linking the Skyway to California’s Interstate 80; and the Yerba Buena Island Transition Structure connecting the SAS to the island.
Among the many seismic engineering innovations incorporated into the bridge design by TYLI engineers, the single tower of the SAS comprises four steel legs connected by fusible shear link beams. It is the first bridge of any kind to use fusible shear links in its tower to protect tower shafts during an earthquake. The East Span is also the first bridge on this scale to use a single, prebent, three-dimensional suspension cable. The 4,550-foot-long cable anchors in the superstructure itself rather than in the ground at either end due to challenging geological conditions. Deck sections are connected by hinge pipe beams that transfer bending and shear, absorbing seismic energy and protecting the main structure. For increased stability, foundation piles were driven up to 300 feet below the water’s surface to reach stable soils, using battered pile technology.
TYLI and its project partners received the APWA 2015 Project of the Year Award during APWA's 2015 International Public Works Congress & Exposition on August 31, 2015 in Phoenix, Arizona.
Photo Credit: Sam Burbank Photography