Concrete does not like to be long and thin no matter how thick it
is. As a general rule the length should never exceed 1.5 of the
width. You will notice joints tooled or cut into exterior
concrete roads, sidewalks, driveways, etc. If the concrete is
cracked, try to visualize why. You are bucking an uphill battle
other than this next bit.

I was quite surprised by an article in one of my magazines.
Here is quite an interesting article from the March issue of
Concrete Construction magazine:
http://www.concreteconstructiononline.com/industry-news.asp?sectionID=691&articleID=456524
If I had read it elsewhere I would have been a doubting Thomas.
It may well give you some of the information you seek.

Concrete countertops are interior and sealed, hopefully the
reinforcement won't start to rust. It is the expansion of the
rust that destroys the concrete.


There are many different acrylic modifiers to add to the concrete
to increase flexural strength. If you have little or no
experience with concrete I would be concerned with your ability to
keep up with the Rapid Set product.

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




wrote in message
ups.com...
On May 19, 6:57 am, RicodJour wrote:
On May 19, 8:32 am, Norminn wrote:



I know next to nothing aboutconcrete, other than a few tips
learned
when speaking with contractors when my hubby was building
manager for
our condo. If I was pondering a project such as yours, I
would use
smallerpaversand no rebar. I'm thinking that the thickness
of the
concreteover the rebar will be only about 7/8" on either side.
Seems
likely you would end up with a lot of burstconcretefrom the
rebar
rusting and no surface strength along the rebar. I
likepaverswith
grass as you describe, but I would be inclined to use
smallerpaversand
forget the rebar.

Sorry to burst your bubble, but with a response like that you
obviously know far more aboutconcretethan you give yourself
credit
for.

R

Pouring a concrete foundation is out, since my site conditions
won't
really allow for it. I can lay a subbase of sand or pea gravel
if
that would hopeflly preventing the clay from heaving.

Given the responses I am willing to pour thicker paver slabs in
place,
given that most who have responded think that this would prevent
cracking. What is the mimimum thickness - 3", 4"? If I pour to
this
thickness, can I avoid intalling a subbase, since that would
entail a
great deal more work?

With regard to the thickness of the concrete being 2" liable to
break
from the movement and rusting of the rebar, how is this problem
avoided with concrete countertops, given that these are
generally cast
pretty thin and poured in long sections with rebar and remesh
from
what I have seen? Obviously countertops are subject to less
tensile
pressure than something being stepped on, but are subject to
moisture.

One of the other options I ran across was a company here in CA
called
Rapid Set (www.rapidset.com/ConcreteMix_data.asp). They make
high
performance concrete which is great deal more expensive than the
bagged Quickrete. It costs about $12 a 60lb bag. I weirdly
enough
ran into a rep yesterday in the Home Depot who said that if used
properly, the stuff is guaranteed not to crack since it is
primarly
used for roads and other high performance situations. It sets in
15
minutes, but apparently this time can be extended with a set
control
substance you can by from them. I am going to call them on
Monday
and see how this could be used, and what adjustments would have
be
made for my specific situation. Just curious, does anyone have
experience with a product such as this?

Naveen