Knowledge CentreTechnical Resources SearchConference PapersExtending the Life of the Angus L. MacDonald Suspension Bridge

Extending the Life of the Angus L. MacDonald Suspension Bridge

Abstract

The Angus L. Macdonald Suspension Bridge crosses Halifax Harbour and connects Dartmouth and Halifax in Nova Scotia, Canada. The bridge was opened for traffic in 1955. The overall length of the bridge, including approaches, is 1,347 m (4,419 ft), and the suspension bridge is 762 m (2,500 ft) long. After almost 60 years of service, the aging bridge deck is experiencing significant corrosion problems and is reaching the end of its service life. Therefore, the owner, Halifax Harbour Bridges, decided to replace the entire suspended superstructure including the hangers.
Bridge inspections showed that all parts of the bridge that are not being replaced (main cables, towers, cable bents and foundations) are in good condition and expected to have a long life. The designs of the new bridge superstructure and its replacement sequence have been completed.
Safety of the public and minimization of traffic disruption have been the central themes driving the
design. 
The entire suspended structure will be replaced sequentially during night or weekend closures. The
bridge will be open for traffic during each working day. An unusual feature of the project is that the
Owner’s Engineer performed a detailed step-by-step analysis of the erection sequence, has designed some of the key erection equipment, and is providing necessary forces and adjustments to the Contractor for his use during erection. The reason for performing analysis that is normally in the Contractor’s scope is to reduce the risk to the owner in terms of cost and delays. Following the
replacement of deck segments, the deck will be raised to increase the navigation channel clearance by 2.1 m at midspan. 
Dehumidification of main cables is being considered in order to extend their service life.

Conference Paper Details

Session title:
Structures
Author(s):
Radojevic, D.
Buckland, P.
Kirkwood, K.
Eppel, J.
Topics:
Structures
Year:
2014