Bruce, thanks for all of that info.

What happens if I refill the tunneled hole with sand?

j/b


"Bruce L. Bergman" wrote in message
...
On Tue, 11 Aug 2009 14:09:58 -0500, "justme"
wrote:

Ok, Lawrence.

I will check to see how much a rental saw will be.

I am considering cutting the concrete as a last resort.

I appreciate your input.

j/b

If you try tunneling a hole under the pool deck or sidewalk from the
outside, plan on replacing the entire slab in a few months anyway. It
will sag, and it will crack, and in totally random patterns.

There is no way to get the compaction of the fill dirt right when
you backfill the hole - short of filling the whole thing in with "One
Sack Slurry" or "Two Sack Slurry"which is (as it sounds) a varying
strength concrete and sand mix.

And even then, if you get any voids in the backfill it's going to
settle and break.

And if you backfill with a cement sand slurry you will play hell
getting to that pipe again next time. Think 'encased in sandstone.'

Can't win for losing anyway... Murphy's Law says that the dirt
/around/ the area you patched will settle differently than that big
block of concrete you poured, and the pipe breaks at the parting line.

Do it right: Rent a concrete saw. Saw cut and remove a chunk of
sidewalk/deck, do your repairs, put the dirt back and compact it
properly as you go, then place a couple of strips of bender-board as
expansion joints and re-pour the slab.

-- Bruce --