A Couple Of Pool Questions

[malcolminthemiddle]

Is it normal for a pool to sit on a piled foundation or can a concrete raft be used instead? Is there a formula to calculate the size of a concrete raft foundation to support a pool?

Any ideas how to creat ergonomic seating within a cast insitu spa integrated into a pool?

Many thanks in advance.

[Naam]

unfortunately there's no answer to your question. it all depends on the soil condition.

[PoolDoctor]

I am not sure what the question is.

Gil

[malcolminthemiddle]

Apologies if I didn't make myself clear. Let me try again.

1. If a Soil Investigation to establish the load bearing capacity of the ground allows either a piled or raft foundation which is the prefered option and why?

2. If a raft foundation is chosen is there a formula to calculate the thickness of the raft related to the weight of the filled pool.

3. If a raft foundation is chosen can it be cast together with the floor slab to form a monolithic structure.

4. Generally is a raft more or less expensive than piles.

[ardsong]

you asked "Any ideas how to creat ergonomic seating within a cast insitu spa integrated into a pool?"

well I would put some wet cement at the future spot for your ergonomic seat and sit down.

the wet cement will form to your body, which looks th best ergonomical fit you can have.

[malcolminthemiddle]

you asked "Any ideas how to creat ergonomic seating within a cast insitu spa integrated into a pool?"

well I would put some wet cement at the future spot for your ergonomic seat and sit down.

the wet cement will form to your body, which looks th best ergonomical fit you can have.

The problem with that idea is that while the concrete is wet it is held in place by formwork with no space to sit down. A pre-formed mold that could be embedded in the concrete while it is still wet would work. Where to find such a mold, that is the question?

[Valentine]

If it is to be built on original land it will already be well compacted & so the floor slab will not need any other support.

[ChrislakBeeGreen]

if you are building on original ground then there should be no need for any suport for the pool, however if the land has been raised or you have a high water table you may need to pile the pool, pilings are better because in some parts of the pool the pilings may be differnt lenths, you shoulds take the pilings down till you hit hard ground, in hua hin we would normally go down around 3-5 meter before we hit solid ground, most areas there is no need.

As for the lay down spa you can make this after the concrete structure, you will need to have the pipes installed before the pool is poured then afterwards design and build the lay down area inside the pool, the use of a air blower and carefull postioned jets will do just as good as any thing you can buy pre made in fiber, for 1hp air blower you can put 8-10 jets depending on the distance to the pump.

[PoolDoctor]

Apologies if I didn't make myself clear. Let me try again.

1. If a Soil Investigation to establish the load bearing capacity of the ground allows either a piled or raft foundation which is the prefered option and why?

2. If a raft foundation is chosen is there a formula to calculate the thickness of the raft related to the weight of the filled pool.

3. If a raft foundation is chosen can it be cast together with the floor slab to form a monolithic structure.

4. Generally is a raft more or less expensive than piles.

Will try to answer within the limits of my own civil engineering knowledge. Raft foundations are generally used in building construction when the building load is required to be spread over a large area. In effect, the raft distributes the weight of the building over a foot print much larger than the building's own footprint. In pool construction, this is rarely required, as the weight of the pool is not comparable to a building (generalizing here). Raft foundations are also used in highly unstable strata, which in itself might make me wonder about putting a pool in that area. Two types of load carrying foundations are generally used in Thailand pool construction- compacted soil, and piles. Even in sandy conditions, compacting is often sufficient. When in doubt though (e.g., Northpoint where we installed the pool), pilings were recommended. I believe that in order of costs, it would be compacting, piling and then raft foundations. Hope that this helps! Gil