InfrastructureNew bridge construction technologies to shore up U.S. infrastructure
Experts agree that there is an urgent need to construct and repair bridges across the United States. Around 70,000 bridges in the country are considered “structurally deficient” by government standards. New technology could help the United States manage its growing, and aging, infrastructure without breaking the bank or levying high taxes on citizens.
New technology could help the United States manage its growing infrastructure without breaking the bank or levying high taxes on citizens.
According to a 2011 report by Transportation for America, there is an urgent need to construct and repair bridges across the nation. Engineers consider around 70,000 bridges in the country to be “structurally deficient” by government standards.
The innovation called the Bridge-in-a-Backpack was designed at the University of Maine in Orono. The technology is licensed to Advanced Infrastructure Technologies. The Bangor Daily News reports that the innovation was approved for commercials deployment last summer.
As this video shows, the Bridge-in-a-Backpack uses several flat, hollow carbon fiber tubes which are rolled up and packed in a duffle bag. Workers unroll the tubes at the construction site and lay them across a steel framework built to the specifications of the shape in the bridge’s arch. The tubes are then inflated and stiffened with a vinyl ester resin, which, according to engineers, makes them stronger than steel.
The tubes form the base of the bridge and are filled with concrete for added strength and a deck is added on top for traffic.
Those who like the new technology say it makes bridges faster to build, last longer, requiring less maintenance, and minimizing the carbon footprint during construction. The technology is lightweight and corrosive resistant.
The technology has been used on bridges built in Maine, and a Federal Highway Administration (FHWA) program is funding backpack bridges in Connecticut and Rhode Island.
The Innovative Bridge Research and Deployment (IBRD) program aims to improve bridge building and repair methods and will fund projects that plan on using “innovative designs, materials, and construction methods,” according to the FHWA’s program description.
Last year the FHWA gave out $5.5 million for projects in nineteen different states and is now accepting applications for this year’s innovations.
Recently, IBRD handed out $400,000 for a bridge outside Seattle that will use Shape Memory Alloy, a new building material that “can deform beyond its elastic limit and fully recover after a seismic event,” according to FHWA’s monthly publication Focus.