After 60 years of service,the 2500ft (762m) long Angus L. Macdonald Bridge in Halifax Nova Scotia is undergoing major rehabilitation. The project includes replacement of the roadway deck, floor beams, stiffening trusses and suspender ropes. Essentially, it is a complete replacement of the entire bridge suspended structure. Whilst the bridge is currently safe for roadway users, the rehabilitation will improve the roadway running surface and extend the service life of the bridge by 75 years.
This is a significant project for the local road users as well as for structural engineering – it is only the second time in history that a deck of a suspension bridge has been replaced while keeping the bridge open to daytime traffic.
Since 2001, COWI North America (formerly Buckland & Taylor) has been involved in the rehabilitation work of “Old Bridge,” as it is locally known. For the deck replacement project, COWI North America provided the final design of the new bridge structure, erection engineering, and design of the major erection equipment (including the yellow gantry used for lowering and lifting of deck segments, and the temporary connection between the existing and new decks).
As the Owner’s engineer, COWI North America is also providing various construction services and assistance to the contractor (American Bridge Canada Company). The team’s approach addresses the major challenges associated with extending the life of the bridge and will improve this vital transportation route for the local community.
This is our first in a series of articles that will highlight various challenging and interesting features of the Angus L. Macdonald deck replacement project. Keep an eye out for new for new posts in the coming weeks!