Maximum size/length of one concrete pour for elevated slab
Maximum size/length of one concrete pour for elevated slab
(OP)
I have an elevated 6" thick concrete slab being supported by concrete walls at perimeter and concrete beams and columns at interior. The footprint of the slab is overall 100' x 120'. I wonder if the whole slab can be poured one time. Do I need a control joint for this size of slab? Thank you very much for your input.





RE: Maximum size/length of one concrete pour for elevated slab
You cannot and should not predict what equipment or personnel he will have. That's his bag and it affects his bid.
Mike McCann
MMC Engineering
RE: Maximum size/length of one concrete pour for elevated slab
RE: Maximum size/length of one concrete pour for elevated slab
If the slab can be done in one single pour, there will be no cold joints, but it will have construction joints (sawed, zip strip, etc.)
If it cannot be done in one pour, it will have at least one cold joint, but will also have construction joints.
Depending on the slab layout, the area between construction joints should be limited to 400 to 600 square feet or so. Cold joints are placed at the end of a day's pour.
Mike McCann
MMC Engineering
RE: Maximum size/length of one concrete pour for elevated slab
For elevated slabs, I rarely spec any construction joints and leave the cold joint placement to the contractor unless noted otherwise on the plans.
Is that muddy enough for you?
Mike McCann
MMC Engineering
RE: Maximum size/length of one concrete pour for elevated slab
Shrinkage cracking due to restraint by the perimeter walls is another issue. These walls will heavily restrain the slab, and cracking will be inevitable. The amount of crack control reinforcement required to control the width of the cracks depends on the useage of the slab.