Calculating weight distibuted on concrete slab with pool on top

Mikepier

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Mar 10, 2015, 10:45:13 AM3/10/15

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I have been using my Intex Ultra frame pool for the past few years on my concrete slab in my backyard and was just curious what is the actual weight distributed on the concrete.

The pool is 14 feet round and holds 3,300 gallons of water. A gallon of water weighs 8.35 pounds, so that equates to 27,555 pounds on the slab.

Calculating the area of the pool, radius^2*PI= 49*3.14= approx 154 ft/sq

So if I divide the weight of the water by the square footage:

27,555/154= 179 lbs per square foot.

Meaning there is 179lbs of weight per square foot on the slab, correct?

How does this relate to the standard strength of concrete? Is it usually 3,000 PSI?

trader_4

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Mar 10, 2015, 11:04:15 AM3/10/15

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I think it's one more math step. A sq ft is 144 sq in. 179/144 = 1.2 PSI.

Whatever the performance of the concrete is, I think in that application
it's irrelevant. What's going to determine if anything happens is going
to mostly be:

1 - The stabilized (hopefully) base that it was poured on. By far
that the most critical.

2 - That the slab is the correct thickness. I guess the strength of
the concrete would come into play there too, but I would think you're
better off with typical concrete at 4" thick, than extra strong concrete
at 2" thick. Whether it has rebar or similar would be a factor too.

Don Phillipson

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Mar 10, 2015, 11:27:53 AM3/10/15

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"Mikepier" <mike...@optonline.net> wrote in message
news:2846653d-1e9b-48a6...@googlegroups.com...

> I have been using my Intex Ultra frame pool for the past few years on my
> concrete slab
> in my backyard and was just curious what is the actual weight distributed
> on the concrete.

> . . .

> Meaning there is 179lbs of weight per square foot on the slab, correct?
>
> How does this relate to the standard strength of concrete? Is it usually
> 3,000 PSI?

If there is a standard, it is probably shown on line at the US National
Bureau
of Standards.

179 lb. per square foot seems safe and normal. Lots of people
weigh 179 pounds and the bottom surface of their shoes totals
less than 144 square inches.
--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)

Col. Edmund Burke

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Mar 10, 2015, 12:01:55 PM3/10/15

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"I'm ready to beam up, Mr. Scott."
:)

Oren

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Mar 10, 2015, 3:57:25 PM3/10/15

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On Tue, 10 Mar 2015 11:14:04 -0400, "Don Phillipson"
<e9...@SPAMBLOCK.ncf.ca> wrote:

>179 lb. per square foot seems safe and normal. Lots of people
>weigh 179 pounds and the bottom surface of their shoes totals
>less than 144 square inches.

..then no shoes equal less

(fuzzy math for me :)

Susan Bugher

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Mar 10, 2015, 4:54:42 PM3/10/15

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On 3/10/2015 10:45 AM, Mikepier wrote:

> I have been using my Intex Ultra frame pool for the past few years on my concrete slab in my backyard and was just curious what is the actual weight distributed on the concrete.
>
> The pool is 14 feet round and holds 3,300 gallons of water. A gallon of water weighs 8.35 pounds, so that equates to 27,555 pounds on the slab.
>
> Calculating the area of the pool, radius^2*PI= 49*3.14= approx 154 ft/sq
>
> So if I divide the weight of the water by the square footage:
>
> 27,555/154= 179 lbs per square foot.
>
> Meaning there is 179lbs of weight per square foot on the slab, correct?

Probably easier in most cases to just measure the depth of water & multiply by 62.4 lb/SF (in your case 2.87' of water.)

> How does this relate to the standard strength of concrete? Is it usually 3,000 PSI?

I gather the pool puts a uniform compressive load on the concrete slab. Concrete is strong in compression but relatively weak in tension.(it doesn't bend well). if the ground under the slab provides uniform support but is weak/compressible the entire slab may sink. If the ground support is NOT uniform the slab may crack but cracking is more likely to be caused by loads that are NOT uniform - cars and trucks for example.

Susan
--

NotMe

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Mar 14, 2015, 1:42:22 PM3/14/15

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"Mikepier" <mike...@optonline.net> wrote in message
news:2846653d-1e9b-48a6...@googlegroups.com...

Matters not the area of the pool. Use the depth of the water to calculate
the load (in^2, Ft^2). The reality after two years the damage is done/not
done. If damaged you may need to fix when the pool is removed. If not
damaged you have no problem

smil...@gmail.com

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Jul 22, 2020, 8:07:11 PM7/22/20

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I want to put a above ground pool near a retaining wall and wonder how the weight of the water will be distributed underground. The retaining wall is 6 feet high. The pool is round and 10 feet in diameter. The water is 42 inches high. The closest part of the round pool is 5 feet from the retaining wall. Is the force of the water going straight down so there is no effect on the retaining wall or does the force of the water radiate outSo it will still push against the retaining wall? Thanks

gfre...@aol.com

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Jul 22, 2020, 9:00:48 PM7/22/20

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On Wed, 22 Jul 2020 17:07:07 -0700 (PDT), smil...@gmail.com wrote:

>I want to put a above ground pool near a retaining wall and wonder how the weight of the water will be distributed underground. The retaining wall is 6 feet high. The pool is round and 10 feet in diameter. The water is 42 inches high. The closest part of the round pool is 5 feet from the retaining wall. Is the force of the water going straight down so there is no effect on the retaining wall or does the force of the water radiate outSo it will still push against the retaining wall? Thanks

The weight of the water will be 217 pounds per square foot static load
plus whatever you put there by standing on the bottom. Since the water
is lifting you that won't be much and your weight that is floating
will be distributed across the pool. If you used 225 pounds per square
foot it would not be unreasonable and I would add 25% to that for a
safety factor. The side walls of the pool should be containing all of
the side load so you don't need to have it touching. In fact I would
avoid it. Leave an inch or so. I doubt it really matters tho.

dpb

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Jul 22, 2020, 10:11:25 PM7/22/20

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On 7/22/2020 7:07 PM, smil...@gmail.com wrote:
> I want to put a above ground pool near a retaining wall and wonder how the weight of the water will be distributed underground. The retaining wall is 6 feet high. The pool is round and 10 feet in diameter. The water is 42 inches high. The closest part of the round pool is 5 feet from the retaining wall. Is the force of the water going straight down so there is no effect on the retaining wall or does the force of the water radiate outSo it will still push against the retaining wall? Thanks
>

<https://gradeup.co/gate-civil-stress-distribution-soil-i-ce381a0a-96b8-11e6-a30e-3429f8dcecc3>