Tips for pulling off massive warehouse pours that nobody talks about

We just wrapped a 120,000 square foot pour using a Somero S-15R, and the slump consistency you mentioned was our biggest headache. The plant was sending out loads that varied from a 4-inch to a 6-inch slump within the same hour. Even with a top-tier pump operator, that variation makes the screed head behave differently every pass. We found that adjusting the vibrator frequency on the fly was the only way to keep the FF/FL numbers where the spec required.

I’m with you on the mesh, but we actualy switched to macro-synthetic fibers for these larger warehouse floors to avoid the "trampled mesh" problem entirely. It saves the guys from constantly hooking and pulling while trying to keep up with the machine. We still had two guys dedicated to hand-tooling around the plumbing penetrations and columns beacuse the screed just can't get tight enought. If those edges aren't perfect, the power trowels will just bounce later and leave a ridge that's a nightmare to grind down.

Those varying slumps are a killer, but you really feel it when the Whiteman STXD66 ride-ons hit the floor. If the slab isn't setting up uniform, your finishers are going to be fighting birdbaths and shadowing all night. I’ve found that running a lithium-based hardener like Ashford Formula or Prosoco LS right after the power trowels helps lock in that surface density. Also, if you’re seeing that much slump swing, check if the drivers are washing out their drums properly. Even a few gallons of leftover rinse water can jump you from a 4 to a 6-inch slump before you even hit the pump hopper.

Don't forget the wind's gonna wreck ya if you're pouring these big ones in July. I've seen crews nail the FF numbers then lose the whole slab to shrinkage cracks 'cause they weren't fast enought with the cure.

We've been using spray-on evap retarders while we screed now. It's a lifesaver when the sun's beating down. Anyone else seeing better results with those vs just soaking the subgrade?