At an offsite location, carbon-fiber tubes are inflated, shaped into arches and infused with resin to harden them. The tubes are then moved to the foundation’s location and filled with concrete, producing arches as strong as steel. The arches are then covered with a fiber-reinforced decking and buried under several feet of sand.
The carbon fiber protects the resin from harsh weather and extreme climates, which safety experts say is the greatest cause of bridge corrosion. In standard steel bridge construction, de-icing road salts and saltwater infiltrate the concrete and corrode the steel bar, which causes it to expand and crack the concrete, weakening the bridge.
The new, environmentally safe design was developed by the University of Maine Advanced Structures and Composites Center and has been named “bridge in a backpack” technology because its components are lightweight and easily transportable.
The new technology could be one way to help rebuild the country’s bridge infrastructure, which has scored poorly in recent years on an annual report card of their integrity. A national conversation about bridge safety continues, a debate first sparked in 2007 after the I-35 Minnesota bridge over the Mississippi River, killing 13.
For more information, read Government Technology's article.