I own a home in Florida that has a crack in the concrete pool shell
near an upper corner, and I need to determine the best method of
addressing stabilization and repair. Let me try to explain the
configuration and what I think is going on:

The pool is rectangular, approximately 15' x 30', and is attached to
the back of a home that is at ground level in the front and one story
above ground level in the rear. Hence, one walks directly out to the
pool, which is set behind a one-story retaining wall. The long side of
the pool is parallel to the house, but the back pool deck is a
trapezoid, so the long dimension on the pool's side away from the house
does not run parallel to the retaining wall. At one end of the pool,
the retaining wall is approximately 3' from the pool edge and corner
and at the other end of the pool, the retaining wall is about 5' from
the pool edge and corner.

The pool is surrounded by concrete decking covered in Saltillo tile. I
assume the decking is tied to the pool shell via the extended rebar
from the pool, as I am told is common, but, as i didn't build the pool,
I cannot verify this without frther detective work.

At the corner of the pool (and there's one problem, it has a 90-degree
corner, not a round corner) at the end 3' from the retaining wall, a
crack has occured which runs roughly from the top corner at a 30-degree
angle downward and along the back wall of the pool. Part of this crack
is above the water line and part below. The crack is about 1/8-1/4"
and extends about 4' in length.

What I think might be going on (just a guess) is that the
expansion/contraction at the end where the deck is narrow and the
retaining wall nearby is such that it is causing the crack and
loosening tiles off the coping. The retaining wall does not appear be
moving, so i don't think that's the issue.

Now, I want to stabilize this deck/pool shell interface before making
further repairs. I wan to solicit solutions from experts, but had the
following idea, which is open to comment. I was wondering if I could
drill down about 24" through the decking at, say, 16" intervals
laterally, into the center of the pool shell and epoxy rebar into these
holes to further strengthen the decking-pool shell interface. Is this
a sensible idea? Others? (It would be helpful if the repairs can be
effected without destroying all the Saltillo decking, if possible.)

Also, I see an interesting new product, Torque-Lock
(http://www.askalanaquestion.com/torque-lock.htm), which looks like it
might have application. Does anybody has experience or comments?

Any and all assistance much appreciated. If anybody needs photos to
better appreciate the layout and design, I'd be happy to e-mail.

Thanks in advance.