cut-and-cover tunnel complete (Phase 1)
pedestrian tunnel network
different Toronto utilities relocated
- More people pass through Union Station every day than through Toronto’s international airport, and that number is expected to double by 2020.
- The PATH tunnel connection on the east side of Union Station was severely congested, prompting the need for a tunnel on the west side as a passenger relief valve.
- Project was adjacent to two concurrent large construction projects and surrounded by heritage buildings.
- Water mains, sewers, gas mains, fiber optics, underground hydro transmission and distribution circuits, overhead and underground street lighting, traffic control systems, and steam heating networks all needed to be relocated.
- All of Canada’s major financial institutions depend on these power and fiber-optic connections.
- Complex 3D models were developed for multiple custom tunnel alignments and utility relocation options.
- Digital construction prototypes in the context of existing conditions allowed full visibility of the utility or structural conflicts.
- Designed custom solutions for unique utility relocations, including for a sewer whose existing profile went directly through the proposed tunnel.
- Designed a siphon, made of 6-millimetre-thick stainless steel, directly between the new tunnel’s floor slab and the existing subway’s roof slab.
- With insufficient space to accommodate a circular sewer, we designed transitions from a circular cross section to a rectangular equivalent cross section and back again, with only 50 mm clearance between the siphon and the structure.
- Built directly on top of the existing subway system in an extremely congested construction area.
- 2016 Willis Chipman Award, Consulting Engineers of Ontario.
- 2016 Award of Honor, American Council of Engineering Companies – New Jersey Chapter.
- Extensive 3D modeling and approval efforts were needed to communicate the scale of complexity to each of the 12 utility owners.
- Contract drawings for construction, detailed plans, elevations, and cross sections were generated directly from the 3D model.
- Also constructed two signature surface buildings.