T.Y. Lin International leads a joint venture that is providing complete design services for the replacement of the 2.1-mile eastern span of the Bay Bridge between San Francisco and Oakland. From conceptual and final design through construction support services, T.Y. Lin International has been involved in all phases of developing the world’s longest single-tower, self-anchored suspension bridge.
- When built, the new Bay Bridge will feature a record-setting, single self-anchored suspension span of 1263 feet.
- First suspension bridge constructed with no connection between the deck and tower.
- First use of Shear Link fuse in the tower of a cable supported bridge
- Precast girder segments for the Skyway weigh 300 to 800 tons, the largest ever built in the world.
- A designated lifeline route whose performance criteria require the new structure to be able to carry emergency traffic soon after a maximum credible earthquake.
- State of the Art design of Hinge Pipe Beams at the expansion joints between bridge frames.
The innovative design includes two main sections; a 525-ft-high, asymmetric suspension bridge with a main span of 1263-ft and back span of 591-ft, and a 1.6-mile twin, streamlined concrete segmental skyway approach. Located near two major California fault lines, the unique, single-tower of the suspension bridge is comprised of four steel shafts connected by “shear link” beams, designed to protect the load-bearing shafts in the event of an earthquake. A single cable gracefully drapes from the tower’s top and loops back below the west end, with slender suspender cables that attach the main cable to girders beneath the road deck. The Bay Bridge will be the first suspension bridge constructed with no connection betweent the deck and tower. In fact, the self-anchored suspension bridge box girders will be “flowing” at the tower, with the suspenders providing the only connection between the box girders and the tower. The Skyway was designed with an optimum span length of 524 feet. The viaducts are composed of five frames to reduce the number of expansion joints needed, the frames serving the dual purpose of accommodating sliding movement but maintaining rigidity to resist seismic motion.
The new San Francisco-Oakland Bay Bridge design includes a cantilevered bicycle/pedestrian path on the eastbound side of the structure, aesthetic lighting and provisions for future light rail. The new East Span will consist of two parallel roadways with five lanes each and two standard shoulders to accommodate over 280,000 motorists each day. No doubt, California’s largest public works project will afford a sweeping panorama for motorists, pedestrians, and bicyclists alike.