Alameda County, California Bridges: Dumbarton Bridge across San Francisco Bay

June 2014 (37.510029 Degrees, -122.11264 Degrees) Dumbarton Bridge

We've left the dry grasslands of Alameda's eastern border for the salt marshes along its western border. South San Francisco Bay is crossed by the San Mateo Bridge and today's Dumbarton Bridge along the western border of Alameda County.  I'm very familiar with Dumbarton because I was one of the minions who modeled its piers for the seismic retrofit that was recently completed.

The photo above was taken from the west end of the bridge in San Mateo County. Dumbarton Bridge (35 0038) is a continuous steel box girder bridge built in 1981. It's on the south end of San Francisco Bay and it's the shortest of the Bay bridges (at 1.4 miles). Stiff piers at the ends and tall piers in the middle makes the stiffer piers carry most of the lateral load during earthquakes. Since the bridge was designed in the 1970s we originally hoped that it would be okay for earthquakes, but we ended up isolating the steel superstructure to reduce the forces to the substructure.

Alameda County, California Bridges: Dumbarton Bridge across San Francisco Bay by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.