13 August 2010

Bridges news roundup

New bridge designs for Perth go on display
Neither the 126m arch or the underslung truss is particularly appealing or well-detailed, leaving voters with Hobson's choice (for full details of each design see the PDFs at the voting website). Given the span and general layout, I'm surprised a suspension bridge isn't offered as an option.

Columbia River Crossing design raises questions
Better safe than sorry, say people made nervous by an unusual "open web" highway bridge design in Washington, USA (pictured). So far as I can tell, the design is for a steel truss with concrete decks top and bottom. I like how the story misquotes a bridge engineer as suggesting that "the concept of using steel in conjunction with concrete is still new". The entire story is shot through with a deep fear of innovation - Japanese engineers are cited as saying they would never again like to go through a project where extensive testing, trialling and confidence-building is required. How else does innovation ever happen?

Base price set at $7.4 million for Peña Boulevard rail bridge
Calatrava's light rail bridge at Denver airport is predicted to cost up to US$60m. Mystery remains as to why they commissioned a design they can't afford. The US$7.4m is the price offered by the light rail system's design-build contractor to span the same gap. They have until January to decide whether they can afford the premium for the Calatrava design, which is a 189m span steel bowstring arch, rising 44m (pictured). I'd guess the D&B firm's proposal is something quite different!

Victoria Council votes to replace Johnson Street Bridge
I've covered this before: the choice between refurbishment of a historic bascule bridge, or its replacement with a new structure designed by Wilkinson Eyre (pictured). Following considerable further study and public consultation, Victoria's council has voted for the latter, but still has to win a referendum in November to be able to borrow the money required.

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