Saw a stat that 70% of concrete pours fail because of bad subgrade prep

I was reading through some ACI stuff last weekend and found out that over 70% of concrete slab failures come back to poor subgrade work. That blew my mind because we spend so much time fussing over the mix and finishing, but the ground underneath is where it really goes wrong. I remember a job out in Denver where we had to tear out a whole driveway because the base wasn't compacted right. Has anyone else seen this play out on a job site?

3 comments

3 Comments

abbyg607d ago

Used to be all about the mix design myself. Thought if the concrete was strong enough, nothing else mattered. But after a big garage slab job buckled on me, I started paying attention. Now ground prep is the first thing I check. That Denver story is exactly what I've seen too. It's the boring stuff that sinks you every time.

jamesm387d ago

That Denver story is a good reminder. I learned my lesson when I built a garden path on top of what I thought was good ground. Looked solid, but after a few rains it was more like a funhouse floor than a walkway. Named it the "Swayback Special" after that. And yeah, @abbyg60, it's always the stuff you think is too basic to mess up that ends up making you look like a rookie.

the_mila1d ago

The "Swayback Special" got me good. Sorry you had to learn that one the hard way.