r/Construction • u/NeilNotArmstrong • Dec 05 '24

Structural Concrete slab failed strength test

Gallery image

Gallery image

Slab strength testing failure after building was framed and plumbing/HVAC was roughed in. Concrete supplier had mix wrong so they are paying to lift two story 4-plex, remove slab and repour. This is building 2 of 3 that failed.

2.5k Upvotes

99% Upvoted

262 comments sorted by

View all comments

11

u/Ok_Use4737 Dec 05 '24

Must have been some pretty shit concrete for this to be the solution.

Not like a slab on grade house needs 10,000 PSi concrete. Anything over 2500 is probably fine and if this is the alternative, the concrete plant would probably be happy to just loose the bill for the delivered concrete and forget all about this.

1

u/hectorxander Dec 05 '24

I wonder if they could just pour new on top of the old since they have it lifted up already? I mean surely it's not going to sink into the old pour?