The Penobscot Narrows Bridge, which spans Maine’s Penobscot River and connects Verona Island to Prospect, has a connection to UMaine’s Advanced Structures and Composites Center in Orono. That connection, however, is through sensors that monitor the force, temperature, and strain of different components for their performance and longevity.
The cable-stayed bridge is 2,120 feet long and features a spectacular observatory at the top of one of its two towers. Positioned 420 feet (42 stories) above the river, the observatory is the only one in the US, and the highest in the world. The idea for the observatory came from UMaine alumni Karen Goodrich Cole ’82 and her husband David Cole ’77, ’78G, who was commissioner of Maine’s Department of Transportation during the bridge’s construction.
The bridge was constructed between May 2003 and December 2006. In 2007, six of the original cable strands were replaced with carbon fiber composite strands, a first in US history. During the installation of the composites strands, UMaine engineers collaborated with state and private engineers to install a system to monitor the force on each composite strand. The monitoring system proved effective in two field tests.
UMaine researchers are now working to upgrade the monitoring system to collect data remotely and throughout the year. The researchers are part of the UMaine-based Transportation Infrastructure Durability Center, a consortium of research universities focused on improving the durability and lifespan of roads and bridges in New England and beyond. The UMaine researchers are studying the composite strands and their response to the temperature extremes of Maine.