http://www.theregister.co.uk/2009/09/23 ... orts_tank/
The US Army, seeking to embiggen its green image, has proudly announced the building of the world's first bridge made from recycled plastic and able to support heavy loads. To test the recycloplast bridge, troops drove a monster 70-ton Abrams Main Battle Tank across it.
“This represents a ‘first of its kind’ event in terms of how we partnered with industry, the R&D community and government in looking for sustainable solutions to infrastructure challenges,” said Colonel Stephen J Sicinski during the dedication ceremony last week.
“What better way to commemorate this, than with a recycled plastic bridge that is going to hold an M1 Abrams Tank.”
The M1 Abrams is one of the heaviest main battle tanks - and therefore one of the heaviest ground vehicles - in current service, with modern examples generally tipping the scales at over 70 tons. The mighty machine is powered by a 1500 horsepower gas turbine and features heavy depleted-uranium armour plate - with an outer facing of explosive slabs on upgraded tanks, intended to disrupt the armour-piercing plasma jets formed by shaped charge warheads or roadside mines.
The M1's use of old uranium from nuclear powerplants is one kind of recycling, but the new bridges built at the US Army's Fort Bragg training centre are another. Made from high-strength thermoplastic processed out of 100 per cent recycled plastic bottles and suchlike, they are described by their makers as "the first known structures of their type to support loads in excess of 70 tons".
The recycloplast bridges are also said to be corrosion resistant compared to other bridge materials, meaning that they need almost no maintenance. Steel structures typically need regular repainting and inspection to guard against rust: timber needs expensive and potentially troublesome coatings or treatments. Procurement officials estimated that there would be a 34 to 1 return on the extra expense of the plastic bridges from reduced maintenance costs.
The recyclothermoplast material comes from makers Axion International, who developed it in cooperation with boffins at Rutgers University. The firm sees it as taking on many structural and building tasks in coming years, replacing "last-generation materials, such as wood, steel or concrete".
