AIT Bridges contributes composite beams to Maine bridge replacement project

The Grist Mill Bridge in Hampden, Maine has reopened after a project to replace an aging steel bridge span with one comprising five composite beams.


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AIT Bridges composite bridge
Photo Credit: AIT Bridges

Composite bridge systems and structural components specialist AIT Bridges, a division of Advanced Infrastructure Technologies (AIT, Brewer, Maine, U.S.) announced on January 5 that the Grist Mill Bridge, located on Route 1A in Hampden, Maine, has reopened after replacement of its former bridge span with composite beams from AIT Bridges.

The company says the bridge’s former span was constructed in 1950 and comprised three bridges built one on top of the another. It has been replaced with a new span consisting of five composite beams manufactured at AIT Bridge’s Brewer, Maine facility. The technology was developed in cooperation with The University of Maine’s Advanced Structures and Composites Center.

composite bridge
Photo Credit: AIT Bridges

This bridge replacement is part of a project that includes reconstruction and paving work on an almost two-mile-long stretch of Route 1A. The total cost for the project is approximately $8.9 million, AIT Bridges reports.

The company adds that its composite bridge systems are designed to last more than 100 years, at least 30 years longer than the average steel bridge. Additionally, because its bridge systems use composites instead of steel, they are reported to require little to zero maintenance over their lifecycle. 

In addition to the University of Maine, AIT Bridges says this project was enabled by partnerships with the Maine Department of Transportation; T Buck Construction; Dashiell Transportation; TY Lin International in Falmouth, Maine; Calderwood Engineering; Composites One LLC in Rockland, Maine; TexTech Industries; Portland Bolt; N.S. Giles Foundation Inc.; Lee’s Concrete; Owen J. Folsom Inc. and Hammond Lumber.

“We’re so pleased to have lent our engineering expertise to the replacement of the Grist Mill Bridge in Hampden,” says Ken Sweeney, president and chief engineer at AIT Bridges. “We wanted to ensure that the construction that took place in 2020 would be long lasting and resilient. By using materials made in Maine by Maine craftspeople, this bridge will stand the test of time.”


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