Originally Posted by harryc
from across the river
Second crane going up - note the micro piles being installed - an afterthought ?
Split level foundation pad ?
It appears that the big - coupled - rebar is being used for the horizontal as well as the vertical - note the staggered endings (earthquake code ?).
extending upper upper Wacker
The attention to ascetic detail is impressive, use a crane with rounded weights when the backdrop is a curvy building.
An excellent question
Rebar size #14 and #18 have to be coupled. As a rule, its good to stagger laps/couplers so you dont have them all in a row. The bottom mat bars could be staggered due to the size and quantity of bars. You need to have room to manuever the couplers and to tighten them down. I believe this is all #18 bar and the couplers look like position couplers to make securing them easier.
As far as concrete pours, they typically butt up to each other, like LVDW mentioned, the shear loads of floors on columns compress the concrete together, the reinforcing ties everything together thru the joints.
Concrete - better in compression
Rebar - better in tension
The perfect marriage.