Don River Bridge
Toronto, Canada
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 The
Sheppard Subway bridge structure over the Don River in Toronto,
Canada, solves special geometric considerations and unusual structural
loadings with a unique design approach. Owned by the Toronto Transit
Commission (TTC) and designed by the consulting engineering company
of McCormick Rankin Corporation (MRC), the Don River Bridge is certainly
an innovative application of concrete technology.
The proposed new subway extension, running beneath Sheppard Avenue,
posed a special problem at the intersection with Leslie Street—this
point also happened to be where the Don River intersects Sheppard
Avenue. In order to avoid the intersection and bridge abutments
at the river crossing, the horizontal alignment of the underground
subway was offset approximately 130 feet, compelling the designers
to create a unique, above-grade bridge to span the Don River. The
design saved the TTC over $20 million. The resulting concrete structure
typically has 10 feet of freeboard, but severe regional storms raise
the river to levels surpassing the top of the bridge, which places
huge hydraulic forces on the structure—stream flows of up
to 18 fps. Of course the structure must also be watertight.
 The single-span structure traverses approximately 200 feet, is
18 feet deep, and varies in width from about 50 to 60 feet to account
for the flared track alignment required at the adjacent Leslie Station
platform. The 3-celled, prestressed, post-tensioned concrete box
girder section houses EB and WB track and a center access-way. To
verify the unique design, a 1:30 scale model was tested for the
hydraulic loads.
The total project cost $932 million and includes approximately
4 miles of subway and five new stations. Construction costs for
the bridge alone were $15 million.
Project Credits
Owner: Toronto Transit Commission
Engineer: McCormick Rankin Corporation
Architect: A. J. Diamond, Donald Schmitt & Company
Contractor: Ellis-Don Construction
Concrete Supplier: Dufferin-Custom Concrete Group
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