INNOVATION IN RAIL AND TRANSIT
hatch mott macDonald
toronto-York spadina subway extension
The Toronto Transit commission engaged Hatch
mott macDonald to design the 6.7-kilometer tunnel
segment of the $730 million Toronto-York Spadina
Subway extension. The twin-bore tunnels pass
under buildings, railways, highways, waterways,
and utilities to connect six subway stations. Hatch
mott macDonald realized cost benefits by using
Bentley software to design the tunnel lining system,
six emergency exit buildings, and seven tunneled
Three-dimensional modeling avoided challenges
related to multidisciplinary coordination of
conventional 2D engineering design. The margin
for error within the subway tunnel was small,
with a host of spatial restrictions such as tunnel
boring machine drive tolerance and subway vehicle
clearance envelop. The 3D coordination was critical
to reducing spatial conflicts.
Track alignment was designed with Inroads,
building structures were analyzed with S TAAD.
pro, and emergency exit building models and
drawings were produced with Structural modeler.
The company used microStation to model the
tunnel lining system’s steel reinforced rings and 3D
modeling of the entire alignment and associated
structures established a single integrated model.