Groat Road Bridges and Road Renewal Project Update
In January 2018, Graham’s Infrastructure Division was awarded the $48 million Groat Road Bridges and Road Renewal Project in Edmonton, Alberta. The scope of work for this project is centered on a full superstructure replacement program on the seven-span, four-lane vehicle bridge that spans 330m across the North Saskatchewan River. The project also involves minor rehabilitation work on the piers, structural rehabilitation of two additional bridges adjacent to the river, and an extensive roadworks program.
This project was awarded to Graham through an evaluated procurement process, and was subject to two major constraints. First, accommodations for traffic and pedestrians needed to be maintained through the course of the project, requiring the work to be delivered in a phased manner. Second, the project was subjected to significant environmental restrictions with limited windows for instream work, and securing the necessary permits from governmental agencies was the responsibility of the contractor after award. Graham’s plan for execution of the project makes use of an innovative construction engineering program not yet seen before in Canada, which involves all bridge work being completed with a pair of gantry cranes running on a custom-built temporary structural steel runway installed onto the current bridge structure. This approach allows the work to be completed with much less environmental impact as compared to a traditional approach, and further allows work to be completed in two phases instead of four. This work plan also introduces an additional safety factor to Graham’s crews during demolition work, allowing all members of the team to stay out of the line of fire at all times.
Graham’s team was hard at work for the entirety of 2018 designing, procuring, fabricating, installing, and commissioning the gantry cranes on site, and developing the engineered procedures for demolition and reconstruction of the structure. Construction engineering work and demolition procedure development took place concurrently, with each influencing the other; several iterations of the demolition plan and associated design were required to develop a suitable solution, which is now fully implemented on site.
With the construction engineering program off the ground, focus has shifted to execution of demolition and reconstruction work in 2019, and demolition activities are in full swing. The engineered demolition procedure is effectively a reverse of a traditional balanced-cantilever bridge construction method; deck sections between individual girder lines are removed first, followed by a balanced disassembly of each girder line into self-supporting cantilevers throughout demolition. Click here to view a short video animating the demolition sequence.
In total, roughly 150 different lifts of this nature are required for each phase of the demolition work, and Graham’s team is working 24 hours per day, 6 days per week to keep pace on this challenging project. This project ultimately showcases Graham’s ability to deliver complex projects through innovative means, reducing impacts to the communities we work in and bringing best-value solutions to our clients.