15 January 2010

Bridges news roundup

Design fantasies for obsolete Bay Bridge span
What to do with San Francisco's redundant Bay Bridge?

Covered bridge pops up in unlikely place
Unusual garage conversion in New Brunswick, Canada

Could Poole's Twin sails Bridge still be at risk?
Landmark opening bridge's 10-year long gestation not over yet?

Bridging the gap between the ages
How much would it cost to build the 1864 Clifton suspension bridge from scratch today? Construction Manager magazine has more details.

Design for Champlain Bridge announced
It's nice to see a network arch (or "Modified Network Tied Arch Bridge", as Vermont and New York states are calling it) used in this way, although I don't know if I'd agree with their contention [PDF] that it's much cheaper to build or maintain than a cable-stay design.

Hang Christiaan Huygens! Here's a Better Suspension Bridge
Researchers into structural optimisation software discover that a parabola isn't the most efficient shape for a cable to suspend or an arch to support a uniform load. But it's unlikely to change a single bridge, because of the complexity of the "Hencky net" truss required, and because for compression elements, they ignore the effects of buckling.

1 comment:

Mark Yashinsky said...

Science fiction writer William Gibson imagined squatters building a shantytown on the Bay Bridge after it's rendered unusable by an earthquake.
By the way, it is only the East Bay truss spans that are being replaced by a new bridge. The West Bay Bridge is a double suspension bridge (with an anchorage in the middle) that was retrofitted and is expected to stay in service for a very large earthquake.