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Focused Growth
Spotlight on Our Projects
DUFFERIN CONSTRUCTION
Utilizing Innovative Rapid Bridge Replacement Technology to Minimize Disruptions on Highway 400
Mosaic Transit Group, a consortium comprised of ACS Infrastructure Canada Inc., Aecon and CRH Canada Group Inc., was contracted by Metrolinx and Infrastructure Ontario to design and build the Finch West Light Rail Train (LRT) Project. Dufferin Construction, along with Dragados Canada and Aecon, is a designated Mosaic Transit Constructor for the project.
Finch West is another major transit project which aims to provide greater mobility in the GTA—in this case by providing additional transit choices to communities in northwest Toronto. The 11-km, 18-stop, $2.5-billion line will carry passengers from the Finch West subway station, which opened in 2017 near the intersection of Finch and Keele Street, to Humber College’s north campus in Etobicoke.
Slated for completion by 2023, the Finch West LRT project involves designing and
constructing stops, a maintenance and storage facility, tracks, communication system, and other required infrastructure. It also included upgrading and rehabilitating the Highway 400 overpass at Finch Avenue West. In the context of COVID-19, the team has been moving full-speed ahead with minimum disruption.
A matter of days...not years!
Rehabilitating the Highway 400 overpass was an essential component of the project and the future operations of the Finch West LRT as the line will eventually pass below the bridge and have its eastbound and westbound track alignments on either side of the bridge piers. Rehabilitating the overpass also breathed new life into this aging infrastructure by extending its life span from 10 to 75 years.
To mitigate disruptions to motorists, transit riders, businesses and the general
public, Mosaic Transit Group employed Rapid Bridge Replacement technology to rehabilitate the overpass. The technology allows for most of the construction work to occur right next to the worksite, thereby minimizing traffic disruptions. Crews can work faster because they are not operating on an ‘active’ or ‘live’ site.
The process involved using fabricated bridge elements constructed in adjacent laydown areas throughout 2019 and 2020. The team also installed 60 large reinforced concrete girders to build the framework for the bridge decks, requiring tons of rebar and 800 cubic metres of concrete. The girders were then hoisted in place on steel scaffolding set up alongside the highway, ready to be moved in place. This technique significantly reduced the duration of traffic disruptions—from years to just a handful of weekends and night- time lane closures.
The result? It took just two weekends this summer to completely dismantle the existing structure and replace the 1,500-tonne bridge. Teams worked around the clock to tackle the southbound lanes over the first weekend, followed by the northbound lanes the next weekend. The Highway 400 replacement was completed successfully while following all public health and safety COVID-19 measures, and with minimal disruption to the community.
With this project component now complete, Mosaic Transit Group and Dufferin Construction look forward to continuing to develop this major infrastructure project to the benefit of communities across northwest Ontario.
14 | THE CONVEYOR | December 2020