Midgell Bridge Replacement
Location: King’s County, PEI
Client: PEI Department of Transportation and Public Works
Duration: 2006
Approximate Value: $5.0 M
Key Staff: Greg MacDonald, Jim Bennett
Project Description
While working for another consultant, the Principals of Harbourside Engineering Consultants designed a replacement bridge over the Midgell River. The bridge is located on the busiest highway on Prince Edward Island.
Harbourside’s Role
The bridge is a 60 meter single span, twin trapezoidal box girder structure supported on semi-integral abutments founded on end bearing piles. Harbourside’s deliverables included tender and construction documents for the new bridge as well as for the temporary supports, construction phasing and horizontal launch details.
Accelerated bridge erection techniques were used to transversely slide new bridge in place during a two-day closure.
Unique Challenges
The project was unique in that the new bridge was built immediately adjacent to the existing bridge and supported on temporary abutments. Traffic was then diverted to the new structure while the existing structure was demolished and new abutments installed. A full closure of the highway was required for only 2 days to allow the new bridge to be horizontally launched onto the permanent abutments and paving of the deck to be completed. This method of construction allowed a very busy highway to remain open, avoided a long, unsuitable off-site detour and eliminated the requirement for a temporary bridge.
Social Impact
For a construction project of this size, an extended closure is typically expected. Completing the replacement in such a reduced time, with minimal highway closures, ensured that this main thoroughfare was kept active, and traffic was impacted as little as possible.
