They are making up mats that they will fly in place with a crane. The giveaway is the wooden 4x4.
I would say that is #6 bar or less as it is two guys handling it. When you get up to #8 and 9, then you are talking Steel.
I have had column or pier steel so dense you had to change the mix to pea gravel aggregate because normal 3/4 diameter aggregate would leave air pockets because the steel was so packed together.
Understood. That said this is way more than the original construction amount seen during the failure of the floor.