Sunday, March 7, 2010

Soft Cut Saw - Crack mitigation

It is pretty much impossible to make a slab completely crack free, the bigger it is the more likely it will crack.  Even loading it with steel won't prevent it.  Finding the real world balance, good fill, steel, good mud and some kind of joint seems to mitigate the bad ones.  At minimum I use tool joints but that isn't compatible with a power troweler.  With a slab this big (2100 sf) we opted for cut joints.

Slab Day

Concrete finishing is more of an art than a science.  There are a lot of guys that can do it and only a few that can do it well.  The extra $0.50 a foot for the good ones is WELL worth it.

Underslab Prep

Next stage is code compliance - thermal break, slab insulation, Plumbing ground work and steel. 

Tip: ALWAYS double check your plumbers work!  I checked his locations but didn't check his flange heights.  I don't know what it is about plumbers but NEVER seem to get the flange height right.  I even gave him a grade stake then falsely assumed (Assume = make an ASS out of U and ME) he knew how to use it...  He ended up being 3" LOW!!!  Should have babysat him - more work and expense.


This site is about as perfect as they come.  Easy to move the machines around, great local material and generally flat.

Backfill required more than 200 yards of compactible fill.  We had plenty, it was nearby it only cost machine time!  Typically the old building Dirt axiom is You pay (a lot) when you need it and you pay (a lot) when you have too much to get rid of it."  That seems to be true most of the time in my experience.
We backfilled in 8" lifts compacting with three passes (minimum) as we went.  Makes for a long day but in the end you can drive your truck on it and it doesn't even leave a track.

We ran out of light on the first day and finished up by lunch the next.