Urban Toronto recently ventured down to The Daniels Corporation’s Cinema Tower construction site for a visit. We caught both excavation and concrete pouring in progress. Here is how the site looked on March 30th. Excavation is still taking place in the back left corner, but we’ll turn our attention to foundation pouring first. See those concrete mixer trucks on either side of the crane up at the surface…
A bucket has just been filled with concrete mix
The bucket is lowered into the excavated pit
A worker waits by the edge of the foundation pit
The foundation pit extends deeper into the bedrock than the lower basement garage levels. The pit will be filled with concrete and reinforcing steel rods, and will act as an anchor at the base of the tower’s central core and its elevator shafts
The bucket is lowered sufficiently close to the worker, who then pulls down on the extending bar which opens the trap closure at the bottom of the bucket
Many buckets will be needed to fill the pit.
The bucket is quickly hoisted back to the surface for a refill. Meanwhile, in the lower right corner, we see a shovel still excavating the east side of the site.
The shovel is operating at the end of a wall of soldier piles, lagging, and braces. Soldier piles are long steel I-beams which are driven into ground at regular intervals. As the excavation of the pit progresses, timber lagging is slotted between the soldier piles to hold back the earth behind them. Braces are added to keep the wall standing until it is naturally braced by the newly built concrete walls and floors of the basement levels.
The shovel removes earth and rock from around a diagonal brace. Excavation around these braces is tricky and time consuming.
Behind the shovel is another type of wall: this caisson wall is made up of interlocking columns of concrete. It is braced by tie-backs, with steel wire ropes anchored to the bedrock in behind. This type of wall where the bracing does not protrude into the pit makes for easier excavation, but it requires an easement under the adjacent property when excavation extends to the property line. Besides securing an agreement with the abutting owner, soil and rock conditions behind the wall must be stable.
We are back a week later, thanks to Red Mars. The excavation of the pit is virtually complete, other than the access ramp itself. Shovels are now put to work to remove it.
Another three days later, thanks to Jasonzed we see that most of the ramp has been removed. When the excavation is complete the shovels will be hoisted from the pit by the crane.
Urban Toronto will return often to the Cinema Tower site during its construction to tell you more about the process of creating a new building. When it is finished, the 43-storey tower designed by Kirkor Architects, will look like this:
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|Related Companies:||City Life Realty Ltd., HOK, Jablonsky, Ast and Partners, Kirkor Architects Planners, Montana Steele, NAK Design Strategies, Page + Steele / IBI Group Architects, tcgpr (The Communications Group), The Daniels Corporation|