Cooling a concrete truck with liquid nitrogen - GIF

Labeled as cooling a concrete truck with liquid nitrogen. Anyone know what's going on here?

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Previously:

https://www.homemadetools.net/forum/...462#post135646
https://www.homemadetools.net/forum/...463#post131853
https://www.homemadetools.net/forum/...111#post130189
https://www.homemadetools.net/forum/...088#post120617
https://www.homemadetools.net/forum/...380#post116689

It is used to cool the concrete to extend working time. There are various schools of thought in regard to its effect on the finished concrete. It changes the mix water to ice, in effect making a mixture of solids; ice, cement, fine and course aggregate. The ice should be allowed to melt back to water and mixed well before it is put into the forms, or else the water can be in pockets, not evenly distributed. It can also be hard on the steel in the truck.

Concrete cures, it does not dry, in hardening. It is a chemical reaction that if cooled down will slow down considerably.
Adding too much water to concrete makes it porous & not as strong as if it would be if you added just the proper amount of water to it to have the reaction complete.

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Cooling concrete with liquid nitrogen