In late 2013 and early 2014, the TTC continued their strong and proud history with CBM and demonstrated their confidence in the company by awarding them contracts for three out of the six subway stations part of the Toronto-York Spadina subway extension – Vaughan Metropolitan Centre Station, Pioneer Village Station and York University Station. This expansion is providing a critical extension for the TTC across municipal boundaries between the City of Toronto and York Region.
The Vaughan Metropolitan Centre Station required one of the largest concrete pours in TTC history, which came with its own set of complexities. There was major planning required for the staging of this pour, not only due to the shape of the structure, but also because of its size and the time constraints involved with working with concrete. Three CBM concrete plants were involved with this particular project, which took 24 ½ hours to complete, with trucks arriving on site every five minutes. According to the TTC, concrete was placed at a rate of 70-100 cubic metres per hour with a total of 2250 cubic metres poured. One of the innovations that allowed CBM to complete this pour with such great success was their use of nitrogen as a cooling agent for the concrete, a technique that is quite unique and not used by many other companies.
When working on the Pioneer Village and York University stations, CBM used SureFlow, a self-consolidating concrete mix to create the massive structural columns that support the stations. The use of this high performance specialty concrete was imperative to the construction of these prominent columns in order to meet all the technical requirements of the job while keeping budgets in-check.
Remaining environmentally friendly throughout these projects was a key objective to CBM. Special techniques were used to control and reduce the heat of the concrete in order to reduce the carbon footprint of the projects. Supplementary content was added to the concrete in order to ensure that it maintained internal heat requirements while keeping environmental needs in mind; this is something that is not normally done in everyday construction.
CBM’s continual focus on service, consistency and quality made them the perfect partner for the TTC and the Toronto-York Spadina subway extension. The strong foundation built between the City of Toronto and the CBM has led to a legacy of strong foundations for city residents and commuters. All six stations part of the expansion are scheduled to open in December 2017.
View the Toronto Transit Commission story: “The Great Big Pour at Vaughan Metropolitan Centre Station.”