When it comes to heritage bridges, few structures are as fascinating as the St. Andrews Lock and Dam Bridge. Located in Lockport, Manitoba, this 100-year-old truss bridge spans 454 meters and is not only a vital commuting route but also plays a crucial role in controlling floods across the Red River.
The bridge is divided into three main sections: a 90-meter west approach, a central structure comprising seven truss spans (including the river dam) each measuring 40.8 meters, and an east approach.
In 2021, MD Steele, led the second round of rehabilitation as the General Contractor, on behalf of the owner, Public Services and Procurement Canada (PSPC). The project, a $45M design-bid-build contract, centered around replacing and widening the bridge deck and reinforcing the structure to eliminate load restrictions. The design for the rehabilitation process was meticulously crafted by Associated Engineering.
One key aspect of the project involved replacing the expansion bearings for Truss span 1 at the Pier 1 location. This required a 600-ton jacking operation designed by Spannovation to raise the span and transfer it to temporary supports. These supports were engineered to carry traffic and maintain the bridge's articulation during the three-week period allotted for replacement works. After the work was completed, the bridge was successfully transferred from the temporary supports to the new bearings. After the replacement, we conducted a comprehensive analysis to assess the bridge's final service condition. This analysis took into account the dam curtain loads and ensured that the support elevations of the replaced bearings maintained overall safety.
Through this series of blog posts, we'll be discussing the conceptual design, detailed design, site operations, and post-operation evaluation. So stay tuned to learn more about this fascinating project and the unique challenges we tackled along the way.