Recently we sat down with Michael Meschino, Principal, and Chongsong Yu, Senior Associate, to talk about their work on the Eglinton Crosstown LRT project, specifically Cedarvale Station (formerly Eglinton West Station).

Michael and Chongsong, thank you for taking some time to chat with us today. Can you tell us about this interesting project?

Michael: Cedarvale Station is one of 15 new underground stations that compose the Eglinton Crosstown LRT project in Toronto. It’s currently under construction and will serve both as an LRT station and also as an interchange station that connects to the TTC University subway line.

Chongsong: We are providing Structural Engineering Services for this station. Our design scope includes the below-grade LRT station, pedestrian and ventilation tunnels, surface structures for entrances, substations, and ventilation equipment. Our office also designed the temporary underpinning structural framings to support the existing TTC structures during construction stages. It’s a very involved, interesting project to be working on.

What’s most unique about this project?

Michael: Since it’s an interchange station, the new LRT will actually run underneath the existing subway, meaning we had to excavate underneath the subway without interrupting service.

Chongsong: In addition, because the LRT station is roughly eight stories below the existing subway, the station required underpinning so that it would be strong enough to withstand the excavation beneath it.

Michael: We were also working with a strict 3-millimetre maximum differential deflection limitation between the subway station units. The part of the existing station that would see the excavation underneath it is composed of three subway box units. It’s these boxes that needed the underpinning. There couldn’t be more than 3 millimetres of deflection between the boxes otherwise the subway tracks would have been impacted and service would not have been possible.

Chongsong: We worked closely with the contractor to achieve this underpinning and stay within the deflection limit. It was 100% teamwork to find the best solution for a smooth underpinning process.

What was your favourite part of this project?

Michael: The underpinning was the most challenging and critical part of the project. From an engineering perspective it was interesting and unique to work on.

Chongsong: In order to achieve this underpinning, we had to truly collaborate with all stakeholders. The planning was very involved, and we were always trying to think ahead. It was a great engineering challenge.

Any final thoughts?

Michael: This project is much bigger than just the underpinning, which is one component of the entire Cedarvale Station. But the beauty of the project being an interchange station, is that it’s critical to the whole transit system and is transformational to the city of Toronto. We love these projects. They are very thrilling and important for the city.

Thank you so much, Michael and Chongsong, for chatting with us.

If you’d like to learn more about this project, reach out to Michael Meschino or Chongsong Yu.