Building Level Ground for AGP
Due to the ledge and slope in my back yard, we had to build up a 2 ft rise on the low side - even after we dug down to the ledge on the high side. The area built up comprises about 50% of the floor area with the remaining 50% being the section dug into the ground.
The built up surface was constructed with damp 3/8" gravel and compacted with construction vibe plate in layers no greater than 4". I have 12" square pavers level (with a 2" rise across the 24' diameter to accommodate compaction over time) and Styrofoam flooring in place for the floor w/ preformed foam coping.
I wanted to dig into the ground more but the ledge is simply too large to remove. Have you ever had to build up a low side before? My fingers are crossed...
I'm on the road, but can upload pictures when I get home.
Hi. Building up a low area is not a problem if done correctly. It sounds like you have done a good job of it and should not have any problems.
One important consideration with built up areas is the size of the ledge outside the pool. The more you build the area up the larger the ledge should be. Hopefully you have close to three feet of built up area outside the actual pool. That should be sufficient to keep the fill from eroding or washing out from under the pool.
The only thing that concerned me with you post is that you are building the pool off level anticipating sinking over time. Using patio blocks over properly compacted soil should not settle over time and building a pool off level will make the entire job much more difficult. The pool needs to be perfectly round and perfectly level. There are no exceptions to these rules.
Building a pool off level will make putting the wall in the track more difficult. It will make the liner fit funny because one side will fill before the other. Wrinkles usually occur when this happens. The end result will look funny also. Two inches is very noticeable when the pool is full of water. I would level the pool. If it settles a little over time, that's not a big deal. It should not settle much and will probably be completely unnoticeable. When the time comes for your first liner change you could always make any minor adjustments if needed.