Owner: California Department of Transportation
The San Francisco – Oakland Bay Bridge is one of the busiest spans in the world with nearly 300,000 vehicles crossing it each day. Construction began in 2002 on the replacement of the east span of the “Bay Bridge” in response to its partial collapse during the 1989 Loma Prieta earthquake. The new structure is a single-tower self-anchored suspension bridge at Yerba Buena Island.
Swivel Expansion Joint Assemblies
D.S. Brown manufactured high performance Maurer System Swivel Expansion Joint Assemblies for installation on sections of the new east span of the San Francisco – Oakland Bay Bridge. This critical seismic application required expansion joints that will accommodate the potential movement caused by an 8.5 magnitude earthquake.
The innovative design of the Maurer System Swivel Expansion Joint Assembly utilizes a swiveling support bar to accommodate large longitudinal, transverse and vertical displacements, as well as vertical rotations of up to 10 degrees. The centerbeams are free to slide on swiveling support bars that provide equidistant control for centerbeams without the limitations of typical mechanical control devices.
Dynamic tests have subjected this joint assembly design to high-velocity displacements of more than 40 inches per second (1015mm/sec) in both longitudinal and transverse directions. Successful test results prove the unique capabilities of this patented device in seismic applications.