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Toronto Relief Line South - Design

15% and 30% design of two mined stations
Estimated cost: Commencement:
February 01, 2018
Completion date:
July 01, 2019
1900 Yonge Street
Toronto, ON ON M4S
Technical data:
Geology description:

The tunnel face is predominantly shale, with a thin competent layer above the tunnel crown, overlain by clayey glacial deposits, silty sands and fill.

Geology types:
Bid cost: Final cost:
$5 million CAD
Service areas:
Construction methods:

The Relief Line South was a proposed expansion to the TTC Line 1 subway with five new stations planned from Osgoode to Pape Station undertaken by the TTC. The project has since been passed on to a new owner (Metrolinx) and further developed as the Ontario Line. Our role on the assignment included the 15% and 30% design for tunnel geometries, excavation and temporary support of two stations and one crossover. Tasks included production of 3D models, drawings, design reports and finite element analysis based on the SEM approach to tunnelling large caverns keeping surface disruption in urban areas to a minimum.

Carlaw Station 3D Model
Broadview Station 3D Model