Tunnelling by Holey, Moley and Yorkie, Torkie Completed
Tunnelling with the four tunnel boring machines (TBMs) is 100% complete Tunnel boring machine Torkie finished the last drive for the project on November 8, 2013, arriving at the extraction shaft located at the south end of the future Vaughan Metropolitan Centre station.
In total 6.4 kilometres of twin tunnels were bored and 8,493 rings were placed to build the tunnels.
Tunnel Boring Machine progress was tracked on Construction Activity Maps using a green line to show sections of tunnel completed. The maps can be found by clicking on the full view Construction Activity Map. Neighbourhood Overview Map
There are two pairs of tunnel boring machines (TBMs) that were used to build the tunnels for the project: Holey and Moley are one pair, Yorkie and Torkie are the second pair. Holey and Moley bored the tunnels south of Finch West Station, the Southern Tunnels. Yorkie and Torkie built all of the tunnels north of Finch West Station; known as the Northern Tunnels. The TBMs build the tunnels using pre-cast reinforced concrete rings.
In the summer of 2011 TBM Holey began tunnelling operations from a launch shaft at the Downsview Park Station site. Holey completed the first drive (1.6 km) on May 1, 2012 after placing 1,041 rings. On December 7, 2012 Holey broke through the headwall at the extraction shaft located on the east side of W.R. Allen Road, just north of Sheppard West Station (currently known as Downsview Station). In total, Holey drilled 1.2 km and placed 785 rings for the second drive. You can watch a video showing how a subway tunnel is constructed and see the breakthrough of Holey.
Late fall 2011 TBM Moley began boring in the tunnel adjacent to Holey toward Finch West station and arrived at the Keele Street extraction shaft on June 4, 2012 after placing 1,025 rings. On March 5, 2013, Moley broke through the headwall at the extraction shaft located just north of Sheppard West Station (currently known as Downsview Station), after placing 800 rings and completing 1.2 km of subway tunnel.
Holey and Moley finished the Southern Tunnels completing 2.8 kms of twin tunnels and placing 3,651 rings.
In November 2011, TBM Yorkie began the first northern tunnel drive from the Pioneer Village Station launch shaft and broke through at the Keele Street/Murray Ross Parkway extraction shaft on November 29, 2012, after placing 1110 rings. TBM Torkie began tunnelling in February 2012 and also broke through at the extraction shaft on November 29th, after placing 1,119 rings. This made project history as the first double TBM breakthrough, a rare occurrence in North America. Yorkie and Torkie completed 1.7 km of twin tunnels on these two drives. (Click here to view a video of the double breakthrough).
On March 19, 2013, Torkie began tunnelling south from the Highway 407 Station site and arrived on June 13, 2013 at the Pioneer Village Station extraction shaft, located north of Steeles Avenue West, east of Jane Street. On April 2, 2013, Yorkie launched from the Highway 407 station site, boring southbound in the adjacent tunnel to Yorkie, and broke through at the Pioneer Village Station extraction site on June 14, 2013. During this drive Yorkie and Torkie bored 1km of twin tunnels and placed a total of 1,365 rings. Both TBMs were then dismantled and moved to the Highway 407 Station northern launch shaft.
On August 15, 2013, Yorkie began the second last tunnel drive from the Highway 407 Station, boring north toward the Vaughan Metropolitan Centre station. On October 7, 2013, Yorkie broke through the headwall at the extraction shaft located on Highway 7, west of Jane Street. Yorkie completed 935 metres of tunnel and placed 623 tunnel rings in the tunnel.
Torkie is creating the tunnel adjacent to Yorkie, and began boring the final drive for the Project on September 13, 2013. Torkie tunnelled 938 meters of tunnel and placed 625 tunnel liners. On November 8, 2013 Torkie completed the final drive for the project! (Click here to watch the third video on tunnelling, featuring the northern tunnels.)
Now that the tunnels are built, the next phases of tunnel work will begin, including the installation of:
Invert slab (flat bottom for the track), safety walkways and conduits
The above map shows the sequence of the tunnelling for the project.