Saturday, October 3, 2009

Vancouver's Bridges: Queensborough Bridge

All of the bridges we've looked at crossing the North Arm of the Fraser River have haunched girders. The engineers must have been after every inch of vertical clearance they could get to avoid collisions. However, I believe there's a few highway bridges near the airport without haunches.

The Queensborough Bridge is the easternmost bridge crossing the North Arm of the Fraser River. In the accompanying photo we are standing up on the north bank looking south across the river and at Lulu Island. There's so much timber floating down the river, that there's barely room for vessels through the shipping channel. I wonder how many of the great forests of the Pacific Northwest still remain?

In the photo you can see the haunched steel girders over the river, the timber fenders protecting the piers, and the very long approach at a steep grade south of the river. The river crossing looks flat, like they didn't maintain a smooth vertical curve over the river. The river spans are supported on pier walls while the approach spans are supported on two column bents.

The Queensborough Bridge was built in 1960 for the City of New Westminster at a cost of $4 million Canadian. It replaced an earlier bridge that was built in 1909. The entire structure including the approach spans is 924 m (3034 ft) long. It was built to provide access to and from the City of Queensborough on Lulu Island.  It was purchased by the provincial government in 1966 and became a connector between Highway 91A and Highway 91 to the south. Like most bridges around Vancouver, it provides vehicle lanes as well as access for pedestrians and cyclists.

I'm surprised that I could find no information on whether the bridge had been retrofitted for earthquakes. Also, I couldn't find out how much vertical clearance it has over the water, although I would guess it's at least 20 m. There is a book Richmond and its bridges: Fifteen crossings of the Fraser River by Alan Dawe (published in 1996) for those wishing more information about this bridge.
Creative Commons License
Vancouver's Bridges: Queensborough Bridge by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.

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