Infrastructure Ontario and Metrolinx
March 2020 - February 2021
Bid-Build
$25 M
The Finch West LRT is an 11-kilometre light rail transit line that will run along the surface of Finch Avenue from the new TTC Finch West Subway Station at Keele Street to Humber College. GIP (formerly GFL Infrastructure) was awarded multiple scopes and stages on the Finch West LRT project, including: wet utilities, excavation, shoring and soil remediation.
The project included the installation 330 permanent soldier piles ranging from 610mm to 1000mm in diameter that are located at the West Portal, U-Section, Sump Pit and the two Access Ramps of Finch West LRT Project. The soldier piles extend 20ft to 50ft below existing grade elevations.
The project also included the installation of nearly 400 permanent interlocking secant wall piles, 1300mm in diameter, which form a permanent secant water cut-off wall. The secant wall ranges from 80ft to 110ft in depth. The secant piles were braced by 4 levels of regroutable tiebacks averaging up to 60ft in depth. There was a total of 230 regroutable tiebacks, out of which, 70 tiebacks were located at the low-overhead clearance conditions which requires special low-headroom tiebacks, installed with drilling machinery that GIP owns. The piles in the Main Entrance are also reinforced with 4 levels of regroutable soil anchors including a complex truss system with internal bracing system.
GIP also installed structural brackets that tie into the permanent structural slabs used for permanent uplift at the main station design.
To work around utilities, a total of 8 micropile walls at multiple project locations in order to maintain the “cut off wall” requirements on the FWLRT project. The micropile walls are up to 22m in depth and range from 8 to 12 micropiles at each location.
GIP also performed installation of large diameter storm sewers between Romfield Lane and Tangiers Rd, including crossing a major intersection at Finch / Keele. A combination of open-cut and cap/lag tunneling methods were used to work around critical existing utilities.
GIP was also contracted to perform the realignment of the existing City of Toronto large diameter transmission water mains at various locations along the Finch LRT corridor. These involve the installation of new 1500mm diameter steel transmission mains, multiple chambers, difficult commissioning plans, and intricate final connections.
The project included work in poor soils, with high water table. GIP developed in-house proprietary drilling procedures using BAUER (BG40 & BG55) machinery to address the challenging ground conditions.
The proposed re-alignment of the storm sewer crossing the major Keele/Finch intersection required work to be completed under a continuous 36-hour operation. Careful planning with the City of Toronto was required to maintain traffic.
