Owner
Infrastructure Ontario / Metrolinx
Client
Strabag
Cost
$255 million CAD
Timeframe
January 2023
— January 2024
Services performed
Dr. Sauer & Partners has been developing tender to detailed design for excavation and support of a 490m long twin SEM running tunnel and the Mount Dennis shaft.
Description
The Eglinton Crosstown West Extension (ECWE) Advance Tunnel 2 project is the second tunnelled section of the extension of the Eglinton Crosstown LRT (future TTC Line 5). The project mainly consists of design and construction of approximately 490m of twin single track SEM tunnels, a cross passage, a portal, and a shaft. The Mount Dennis Shaft is a reinforced concrete structure which has an average height of 7.9m, a length of 24.2m and at its widest section is 17.2m wide. The SEM tunnels are designed using a typical dual-lining system, approximately 6.5m in diameter, sized to fit a single LRT vehicle and an emergency walkway. One of many challenges is the crossing of the twin running tunnels less than a metre under critical utilities, both running parallel and perpendicular. The SEM design foresees a flexible construction approach for securing the utilities in place during construction.
Geology
The geology is made up of fill overlaying glacial deposits of sands, silts, and clays. The tunnel alignment mostly traverses sand and silty sand deposits.
Location
Toronto, Canada
Highlights
- Large diameter utility crossings in soft ground
- Waterproofing connection details between running tunnels, cross passage, and shaft
- Fire analysis to assess serviceability of the structures during a catastrophic event
Stratigraphy modeled in RS2
Cross Passage modeled in Abaqus