Swimming Pool Design 1

See thread507-95743

Thank you for the link reference, but that thread, from over 2 years ago, does not include any useful structural design references. It's got some links to references that show you how to design the dimensions of the pool...but not anything for the structure.

I've already searched engtips.

Surely the structural design is the same as for any tank???

Loui1 - we do a number of pools in our firm and we went through a research effort to determine what there might be "out there" as far as standards, design criteria, etc. for structural design of pools. Not much found.

We simply use our engineering reasoning/design skills and design the pool walls as cantilever retaining walls resisting two load conditions:
1. Pool full with water pressure on one side and earth pressure on the other (based on geotech report).
2. Pool empty (for maintenance or over the winter) with earth pressure on one side only.

Load combination 2 most always controls. We morph the footing of the wall into the floor of the tank. Joint details are critical - we use waterstops at all tank joints. That's the overall concept in a nutshell. There's detail and durability issues for the concrete of course. And the geometric design criteria you referred to in the link is also critical. We usually have to submit the pool design to an agency in our state that reviews it for health considerations.

You might want to stipulate that the earth is to be cut back until the walls are cured. Than added water and earch backfill to the pool 1 ft increments. While the design should always include the load case with the pool empty it is a good construction practice to eliminate problems.

One problem that I've had trouble finding help on is bouyancy. I've heard the fiberglass pools have sometimes popped out of the ground like boats floating on water. The construction practice above ensures that this boat effect doesn't happen during construction

With regard to JAE load case (1), I believe it is common practice in sanitary structures to ignore the resistance provided by the soil on the outside of the structure.

That's a good idea mrengineer.

Thanks for the replies. So it appears I'm not going to be "swimming" in a "pool" of specific references or design guides.

The design cases you've listed are all things already in my mind. I've heard of concrete pools floating out of the ground due to bouyancy....not even from groundwater, just a leaky pool floated on up when emptied.

Check out the south florida building code. Available via construction school book stores. It is very detailed about the do's and don't of pool design keeping safety in mind along with some of the toughest building codes in the USA- Thanks to hurricane Andrew that hit us in the early 90's.
Pools "pop out" of the ground for two reasons.
1. Pools get drained in areas with high water tables without removing the hydrostatic plug located in the pool's main drain. Turning the pool basically into a concrete boat.
This is usually done either by idiots working for pool companies or homeowners that are just unaware. 99% of pools have a wellpoint buried 2 feet below the main drain in the pool. This wellpoint can be hooked up to a dewatering pump that will actually dewater the earth and cease any uplift pressure.
2. Pools in areas with expansive soil conditions when subject to high rainfall amounts. Basically squeezing the pool until it pops. This is not very common due to the weight of the water and concrete- also the friction of the soil on the outside of the pool walls tends to hold them down.
You can contact for your engineering plans.