Marin County, California Bridges: The Richmond-San Rafael Bridge across San Francisco Bay

December 2015 (37.9440, -122.4802) Richmond-San Rafael Bridge

This week we'll begin studying the bridges in Marin County, California, a scenic and affluent region just north of San Francisco.

Today's structure is the Richmond-San Rafael Bridge, which carries Interstate 580 between Contra Costa and Marin Counties across San Francisco Bay. It's a double cantilever through truss with a sway back section between the two cantilever frames. I previously showed this bridge from Contra Costa County. Today we see it from Marin County just north of San Quentin State Prison.

The bridge has two decks, each carrying two lanes of traffic and a break-down lane. It was built in 1955 and was considered to be the ugly duckling of the Bay Toll Bridges. However, I like it's unusual appearance. Also, I prefer driving over this bridge in order to avoid all the traffic on the San Francisco-Oakland Bay Bridge.

After the 1989 Loma Prieta earthquake the Bay Bridge was closed for a month for repairs while the Richmond-San Rafael Bridge remained in service. Both bridges were recently retrofit, but unlike the Bay Bridge, the Richmond-San Rafael Bridge wasn't retrofit to remain in service following a large earthquake.

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

Solano County, California Bridges: I-80 Bridges across the Carquinez Straits

January 2014 (38.064 Degrees, -122.225 Degrees) Carquinez Bridges

Yesterday we looked at the Napa River Bridge and the Mare Island Lift Bridge from the tower of the Carquinez Suspension Bridge. Today we are looking at the Carquinez Bridges from the deck of the Mare Island Lift Bridge.

The Carquinez Bridges include a 1950s era truss bridge and a new suspension bridge. We studied these bridges previously when they were building the suspension bridge, retrofitting the truss bridge, and removing the 1920s era riveted truss bridge.

The remaining truss bridge got an interesting seismic retrofit in the1990s that included shock absorbers at the expansion joints to prevent unseating at the ends of the cantilevers (above) and supports at the bottom of the towers to facilitate rocking (below).

The bridges carry westbound and eastbound I-80 traffic across the strait that connects San Pablo Bay (on the west) to Suisun Bay (on the east).

The photo shown below was taken before they completed the suspension bridge and before they removed the 1920s truss bridge. On the north (far) side of the bridges is the city of Vallejo and on the south (near) side is the town of Crockett that includes the big C and H (California and Hawaii) Sugar Refinery.

Solano County, California Bridges: I-80 Bridges across the Carquinez Straits by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Alaska's Bridges: Tanana River Bridge

December 2002  Tanana River Bridge  (lat. 63.317·, long. -142.45·) Alaska Highway

Alaska's Bridges: Tanana River Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

Great Britain: Firth of Forth bridge

My plane had trouble taking off (bad generator) and landing (earthquake damage). My friend who flew on American Airlines arrived in Santiago at the same time as me although he took off (from Texas) six hours later than I did.

I had meetings all day and now I'm exhausted from two days of travel. I wanted to put a bridge photo from Chile on my blog but it will have to wait until tomorrow.

In the meantime, enjoy this view of the Firth of Forth Bridge in Scotland, maybe the most beautiful bridge in the world.

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