Milestone for Athabasca River Bridge Construction: 200T South Girder Pair Launched

On February 28, 2024, a significant milestone in the construction of the New Athabasca River Bridge was reached. The south girder pair in the west span was successfully erected. This operation entailed the launching of a 200-tonne, 71-meter-long girder pair from the staging area behind the west abutment to approx. 50m towards the east. Following this, a tandem lift was executed using a 500T mobile and a 400T crawler crane to erect the heavy segment. The photo below displays both cranes holding the girder pair in place as workers in manlifts install minimum bolts in the air splice to the previously erected pier segment.

Tandem lift of 200 tonne girder pair by LTM1500 & LR1400. Air-Splicing to pier segment.

The steel erection crew from N-Force Crane & Equipment Ltd. skillfully maneuvered through an intricate procedure. The process included driving the pair backward with the west end resting on a truck trailer and the east end lifted by the 500T mobile crane. This crane was positioned behind the abutment and below the girder's soffit, enabling the pair to pass above it.

500T Mobile crane lifting the east end of the girder pair as it passes above the crane body.

Once the crane was within the lifting radius of the 400T crawler positioned along the span, the load at the east end was gradually shifted from the mobile crane to the crawler using a load transfer triangle until both cranes were bearing equal weight. With both cranes holding the east end, the pair was further driven east until the trailer reached the west abutment. After this, the full load of the east end was transferred to the crawler crane. Then, the mobile crane was disengaged and reconfigured to lift the west end, allowing for a tandem lift of the 200-tonne pair in conjunction with the crawler.

Illustration showing the stage at transfer of east end of girder pair from Mobile to Crawler

At this stage, the southern pair has been installed, and preparations are now underway for the installation of the northern pair. Spannovation is working diligently behind the scenes, providing real-time construction engineering support to N-Force, ensuring the project progresses smoothly. The collaboration between the construction and engineering teams, facilitated by N-Force's in-house engineering liaison, has been key in preventing site delays.

For more details on the project's background, please visit this news feature.

Significant project parties include:

Owner: Alberta Transportation

Designer: COWI

General Contractor: Alberco Construction Ltd

Fabricator: Central Welding & Ironworks

Erector: N-Force Crane & Equipment Ltd.

Construction Engineer: Spannovation Consulting