Bridge construction passed a significant milestone with the installation of Europe's first plastic span built for a highway, according to the designer. Bridges of polymer reinforced with glass and carbon fibers have until now been intended primarily for pedestrian use. But the 10-meter span deck put in place this month near Oxford, England, is designed for axle loads of 40 tonnes, the heaviest allowed, says Sam Luke, director of advanced engineering at the design firm Mouchel Group, West Byfleet.
|Span reinforced with glass and carbon fiber costs the same as conventional bridges, but saves money on maintenance, designer says.|
The contiguous road carries between 200 and 300 vehicles a day. The bridge cost about $625,000, roughly the same as conventional structures, but it will demand less maintenance, Luke says. He sees the immediate future of polymer structures as deck replacements on existing girders, but he predicts that plastic bridges will eventually provide an alternative to concrete and steel for on other highway and rail crossings. The 38-tonne bridge at Oxford is part of a $4.5 million, four-year European Union development project run by a seven-firm consortium.