Steel Shots: Transbay Transit Center Tops Out

Steel work is complete for the new Transbay Transit Center in San Francisco, a $4.5 billion state-of-the-art bus and rail station that will accommodate 11 transit systems from the Bay Area and Southern California.

Wrapping the entire perimeter of the structure is an architecturally exposed structural steel (AESS) frame that comprises the building’s seismic force resisting system – an eccentrically braced frame (EBF) arrangement – fitted with cast steel nodes at each critical junction point of the frame. The steel pipe columns and cast nodes that form the exoskeleton of the structure are engineered to exact specifications that are test-fitted at the fabrication sites to ensure quality.

A total of more than 24,000 tons of steel was used to construct the Transit Center, all of which was supplied and fabricated domestically in accordance with the project’s Buy America status. Production facilities in around 20 states have been involved in providing the steel for the project, several of which are AISC Members and AISC Certified facilities. (View a map of the various facilities.)

When finished, the Transit Center will accommodate approximately 100,000 travelers daily. Bus operations are scheduled to begin in late 2017. For more on the project, visit To read more about the project’s central feature, the Light Column, see the post “Transbay Transit Centerpiece Installed.”