The University of Maine’s Advanced Structures and Composites Center successfully tested a rapidly deployable bridge system using composite girders and precast concrete deck panels.
The bridge system can be used for highway bridges, pedestrian bridges and military applications. The design is targeted for short- to medium-span bridge applications, up to 80-ft. unsupported spans. The lightweight highway bridge superstructure can be built in 72 hours, a considerable improvement on the time it normally takes to build a bridge.
In addition to significantly reducing construction time and logistics, the new bridge girders are designed to last 100 years, and the precast concrete deck is designed to be easily removed and replaced.
Engineers, Maine Department of Transportation officials, business leaders, investors, researchers, members from Advanced Infrastructure Technologies (UMaine’s licensee for the original “Bridge-in-a-Backpack”) and staff attended the test event. A bridge span was strength-tested in the laboratory using computer-controlled hydraulic equipment to demonstrate that the bridge can withstand the truck loading specified in the American Association of State Highway and Transportation Officials (AASHTO0 Bridge Design Specifications.
“Today’s bridge test exceeded our expectations,” said Dr. Habib Dagher, executive director of the UMaine Advanced Structures and Composites Center. “The composite bridge withstood forces equivalent to more than 80 cars stacked on top of each other, and more than five times the HL 93 design load specified by AASHTO. The composite bridge girder exceeded twice the collapse strength of steel and concrete girders.
“Today was truly a remarkable engineering achievement made possible by research sponsored by the U.S. Army Corps of Engineers and the dedication and hard work of University researchers.
“This bridge system is designed with construction logistics in mind,” Dagher explained. “The bridge girders weigh only 1 to 2 tons for 40- to 80-ft. spans, so that they can be erected with locally sourced common rental cranes, making them easy to deploy in most locations.
“The unique girder shape was designed to be nesting and stackable. As a result, three to four bridges can be transported on a single flatbed.”
“As the commercialization partner of the Center’s composite arch bridge system, today’s event allowed us to showcase this new technology with potential investors as well as DOT partners and executives,” said Brit Svoboda, Chairman and CEO of AIT Bridges. “We’re ready to go to market.”
U.S. Sens. Susan Collins and Angus King issued a joint statement about the bridge system test:
“Maine, New England, and our nation need innovative technologies that will accelerate bridge construction, reduce traffic disruptions, increase the lifespan of infrastructure, and decrease costs to the taxpayer,” the statement reads, in part. “The private sector partners and DOT officials attending the test will help to ensure that such critical technologies are quickly brought to market.”