Hello, my name's Kirk Roberts, and I'm a project manager with Concrete Jack, the company with the PoolDeckLeveling.com website. Our process, which is called slabjacking, mudjacking, concrete leveling and various other things, depending on where you live, works quite well on all types of pools; vinyl-lined, drop-in fiberglass and concrete. We do use two different materials, one of which, expanding polyurethane foam, is only used around concrete and drop-in fiberglass pools. We use a soil based grout material for around vinyl-lined pools (the foam is injected as a liquid, and if the seams between the vinyl-lined pool panels aren't sealed well, it can get between the panels and expand, which would cause problems). The grout is course and dry enough (injected at a consistency between hummus and peanut butter) that this doesn't happen.
Though there aren't many photos of vinyl-lined pools on our website, but we do up to five of them a week, all over Virginia and North Carolina. In response to the comments about pressure, pool walls are much stronger than concrete; we routinely lift slabs around vinyl pools that don't have any water in them, though it is preferable to have the pool full during work, and also use the material to void fill under and around fiberglass steps which are bouncy. If you have indications of a fundamental failure of the pool wall, such as bowing walls, it would be best to empty the pool, pull the liner and check out the wall before attempting concrete leveling. We work quite frequently around all kinds of structures that are much more fragile than pools.
Voids around pool decks are one of the most common causes of floating liners, as surface water from precipitation or irrigation runs under the deck, through the seams in the pool wall and gets between the pool wall and liner, causing the liner to float (ground water can do the same thing). It is quite common to find up to 2 foot voids under the concrete decking surrounding vinyl-lined pools. The concrete leveling process works by filling the voids with the injected material (foam or grout), and then after the voids are filled continuing to inject material, which displaces the concrete up. Our video page,
http://www.concretejack.com/viewvideo/3 ... -animation, shows an animation of the process at work.
Here's a link to the page with before and after photos of concrete pools where we have lifted the concrete:
http://www.concretejack.com/pool-decks/ ... ter-photos
Here's a link to the page with before and after photos of vinyl pools where we have lifted the concrete:
http://www.concretejack.com/vinyl-pools