As Metrolinx’s Toronto teams continue to work on the various ongoing transit expansion projects, the company’s Mississauga portfolio is also moving forward. Last week, the Hurontario-Main LRT, which was named after the late Mississauga Mayor Hazel McCallion when it opened, took another significant step forward with the successful installation of a new underpass for the future 11-mile light rail line.
A new underpass has been successfully installed at Port Credit Station, image courtesy of Metrolinx
The main challenge for the project since construction began was to devise a strategy for laying tracks on a route that is already heavily developed with the existing transport infrastructure. The route intersects with a number of major regional highways such as the QEW and the 401, as well as transit systems such as GO Transit’s Lakeshore West line. Therefore, finding a way to remodel these pieces of infrastructure without causing significant disruption is one of the key factors to project success.
The primary approach to solving this problem was demonstrated in November last year when the construction team used the innovative push-box system to create a new underpass beneath the QEW. The system’s name is quite literal; The ground beneath the freeway was excavated and at the same time a hollow concrete box was slid into the excavated opening, providing structural support for the freeway while also allowing for a new underpass underneath. And all of this in just 55 hours.
A drawer was used to create an underpass while also supporting the existing infrastructure above, image courtesy of Metrolinx
Just last week the team undertook a similar process, building a new underpass at Port Credit Station a few miles to the south, but this time there was an added layer of complexity; The underpass they planned was to be below the tracks of the Lakeshore West GO Line, and with 33,000 passengers relying on the line each day, the work had to be completed without disrupting service. The only way to achieve this was by using the Italian designed Verona System, manufactured by Pertucco Box Jacking Systems.
The GO train travels over Verona System supported tracks, image courtesy of Pertucco Box Jacking Systems
The Verona system represents the first deployment of this system across Canada, providing temporary structural support for railroad tracks to allow operations to continue while work is carried out below. In this case, the system consisted of a series of robust steel elements (blue) installed parallel to the tracks and spanning the full width of the excavation area that runs vertically below. These steel elements rest on poles on either side of the opening and support a latticework of smaller pieces of steel that add another layer of support to the tracks.
Drawings of the Verona System deployed at Port Credit Station, image courtesy of Pertucco Box Jacking Systems
With the Verona system installed, the crew could proceed to install the next drawer and push the 6,000 tonne concrete mass into place under the Lakeshore West tracks. A time lapse of the excavation and advance can be seen in the video below.
With this engineering process now complete, workers can proceed with the expansion of the existing Port Credit GO Station, which will be the southern terminus of the Hurontario-Main Line, and a new high-traffic interchange connecting the western GTA to downtown Toronto. The project is scheduled to be completed in 2024.
UrbanToronto will continue to monitor the progress of this development, but in the meantime you can learn more from our database file linked below. If you wish, you can join the discussion in the dedicated project forum thread or leave a comment in the space provided on this page.
* * *
UrbanToronto has a research service, UrbanToronto Pro, that provides comprehensive data on metro Toronto development projects from concept to completion. We also offer instant reports, downloadable snapshots based on location, and a daily subscription newsletter, New Development Insider, that follows projects from the first application.