On Apr 27, 2:28*am, nestork wrote:
If I were building a driveway, I would pour it 8 inches thick instead of


The problem is that when they pour a typical garage pad or drive way,
THEY DON'T put the rebar where it's needed, which is at the top and
bottom surfaces of the slab so it's in the proper location to resist
bending of the slab. *Instead, they just put a layer of rebar in the
MIDDLE of the slab; equidistant from the top and bottom of the slab
where it's unable to prevent the slab from bending. *So, the slab bends
easily to the point where the concrete cracks, and for $50 more for a
second layer of rebar and $100 more in labour to install that second
layer of rebar before pouring the concrete, you could have prevented
that driveway slab from cracking.

Really, when they put a layer of rebar in the middle of a slab, the
purpose is NOT to strengthen the concrete like it would if you had two
layers. *The purpose of that single layer of rebar in the middle of the
slab is simply to hold the pieces of slab together AFTER it cracks. *The
idea is just to prevent any cracks from spreading. *TWO layers of rebar
would also prevent any cracks from spreading, but two layers properly
located would go a far sight further to prevent the slab from cracking
in the first place.

If you made drywall the same way they pour your average driveway, what
you'd have is a layer of paper sandwiched between two 1/4 inch thick
layers of gypsum. *Something like that is gonna break if you breathe on
it too hard. *Putting the paper on the outsides makes the drywall strong
and rigid because it takes a lot of force to stretch paper. *Ditto for
steel, and putting steel on the outsides of a concrete slab would make
for a very much stronger and more rigid slab of concrete; one much less
likely to bend to the point where it cracks.

--
nestork

The above is true.
Plus expansion/movement joints at intervals.
Easiest to put in when the job is finished with a diamond disk cutter.
It only takes one delivery truck on your driveway to crack it.