The Preservationist

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How does that work since you end up with a cold joint midway through the slab
I'm looking at the amount of rebar including the large amount of vertical ties, frankly I've never seen so much used. I believe they've added enough steel to compensate for the "cold joint". With rebar a limited number of horizontal "cold joints" do not significantly weaken a vertical structure.
 

MrHappypants19

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I'm guessing that the full weight of the transfer slab was a bit too much for the existing two floors below to support and that the first pour here once cured will support the second pour.
Concrete pours typically require minimum 3-4 floors of reshoring below the pouring slab. Seeing as how they wanted to have access to ground floor, you are probably on the right track given that that would have had to leave the double height formwork in longer if they wanted to pour it in one shot. Horizontal construction joints have to get approved by the Structural Consultant and they would typically tighten the spacing of the shear hooks (the rebar to hook on both the top and bottom mats of rebar for transfer slabs) to minimize the impact of the construction joint.

Either that, or the concrete supply was unable to supply all the concrete within the allotted time slot without impacting their other job sites, noise permits, lane closure restrictions etc. so the horizontal joint may have been inevitable. Very difficult to allocate +500cu.m to only one job site during the course of a working day in toronto if they were not allowed to pour at night.
 

whatever

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I was also wondering if the depth of the pour had something to do with it. That transfer slab looks massively thick. How does that affect the curing? Would a single pour that thick cure properly, in any reasonable amount of time?
 

UtakataNoAnnex

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Lenght of curing is directionly proportional to the thickness and size of the thing being cured?
 

whatever

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I'm not a chemist or a materials scientist, but no, I'd imagine it isn't directly proportional. Intuitively, that seems like the kind of thing where an inverse square law would apply?
 

UtakataNoAnnex

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I'm not a chemist or a materials scientist, but no, I'd imagine it isn't directly proportional. Intuitively, that seems like the kind of thing where an inverse square law would apply?
I'm just guess'imating here. As I strongly suspect the curing length is related to its size and depth. I have no idea how proportional it is outside of it taking longer though.
 

jibsta

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I'm not a chemist or a materials scientist, but no, I'd imagine it isn't directly proportional. Intuitively, that seems like the kind of thing where an inverse square law would apply?
definitely.. the hoover damn needed refrigerant otherwise it would have taken 150 years to cool and cure
 

heatscore

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This reminds me of the gigantic pour for the "raft" foundation of 1 Bloor East; the single biggest pour I remember reading about on this site.
Might be worth looking through those pages for those interested.
 

khaldoon

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This reminds me of the gigantic pour for the "raft" foundation of 1 Bloor East; the single biggest pour I remember reading about on this site.
Might be worth looking through those pages for those interested.

Thanks for the reminder. This UT front page story summarized the “event”:

https://urbantoronto.ca/news/2013/01/big-pour-turns-heads-one-bloor-east-0
 

ChesterCopperpot

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The Sugar Wharf raft pour laughs at the 1BE pour

 

thaivic

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C2827ECF-39FB-479D-B6EF-C1A1203539AA.jpeg
18A8482A-9957-4772-95B4-FAC7C0B3E9B8.jpeg
 

ushahid

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Today Mizrahi developments insta page has been posting these black and white pictures of the progress since 2017. I feel like something's cooking.
Screenshot_20210727-190916_Instagram.jpg
 
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