New AGP - Backfill / Settling

[MartinG]

Hello all - first post. I've been reading for a bit here over the last few weeks, while I've been working on getting my new pool ready.

I have a quick question about backfill and timing an some slight settling. My pool is a 30 x 15' oval with 5 steel buttresses on each side for extra support. They are on (I think) 8 x 8 paver blocks. I had a pool company do the install.

Anyhow - the pool was installed on Aug 22 and it wasn't full enough for backfill until about 1.5 days later. It rained a bit in the interim (not a lot, but there was an inch or two of a moat on one side of the pool afterward). Once the pool was ready, I backfilled a few inches up all around the pool, leaving the ends of the buttresses exposed for electrical bonding. My electrician can't come out for another few days (this Friday, Aug 31) and asked that I not bury anything so he can do his part. It's not supposed to rain again until then, but I have concerns over leaving the rest of the fill for too long. I've noticed two pavers under two buttresses (interestingly enough, they are exactly opposite each other) have slightly shifted so the steel feet are not perfectly in the center of them. They are not perfectly level - maybe .5" difference from end to end. There are no other ones like this and everything appears to be level otherwise. I'm concerned the small amount of rain may have caused this (but if I had buried them, i'd never notice).

My questions are: 1) Is this normal for a small amount of settling, 2) is this something worth draining and restarting for, and 3) Is it safe to leave the buttresses exposed for a few more days (i'd only be filling with dirt and not nec with any grade that far out from the walls - they do extend more than a foot out..) I've read the pavers help support the buttresses more than the weight of the water (outward pressure vs. downward). Any concerns?

Thanks..

 

[Teald024]

Hello and Welcome to TFP!!

Congratulations on the new pool! Some small amount of settling is normal can happen with an AGP. The amount will depend on the type of soil under the pool. I don't think it's worth draining and restarting unless the settling is significant or causes the pool to shift out of shape. You should call your installer and get their opinion since they should be warrantying the install. Leaving the pool un-backfilled is risky if rain is expected. If it will be dry, then you shouldn't have any issues. The purpose of the pavers is to provide a solid surface under the legs that can support and spread the load to the ground. Something that the legs can't sink into. The majority of the water weight is supported by the ground under the liner. Some weight is transferred to the liner when it stretches and will pull down on the walls/legs.

Stick around and read through Pool School and the TFP pool care methods. It will go a long way to help you keep your pool trouble free.

 

[hotchalupa]

Congratulations on the new pool! What kind of soil do you have on your property around the installation site? I have a glacial silt that packs as hard as concrete and I still had a very slight amount of settling. My pool is a 32x16 and one end settled just shy of 1/4 ~ 1/3 inch compared to the other end. This was over the course of a few months and seems to have stopped (pool structure has been up for almost a year now). As mentioned above, this will depend on the type of soil. I think a half an inch is within acceptable spec, but I would check with the PB and the pool manufacturer to confirm.

Hope you get to enjoy your pool for a few more weeks before the winter hits!