Wetlook World Forum

Current time: Sat 20/04/24 12:41:51 GMT

Translate page FROM -> TO

Translate page TO <- FROM

Message # 14168.3.1.1.1

Subject: Re: Re: Re: Re: Off Topic: How to build a pool?

Date: Mon 17/01/05 21:45:05 GMT

Name: AnthonyX

Email: anthonyx@jowc.net

Website:

Report Abuse or Problem to Nigel at Minxmovies
If you enjoy this forum, then please make a small donation to help
with running costs: (you can change amount)

Water pressure is exerted equally and uniformly in all directions (up, down, sideways, etc.), and depends on the depth. Since water is essentially incompressible under "normal" conditions, pressure at a given depth will be equal to the weight of the water column above a given unit of surface. In other words, at 1m depth, pressure will be 1,000kg/sq.m. or 100g/sq.cm. In "english" units, at 3ft deep, it will be approx 200lb/sq.ft. or approx. 1.5lb/sq.in. At 2m depth, it will be 2,000kg/sq.m., etc. or in english units, about 3psi. at 6ft depth. The total sideways force on a vertical wall would be proportional to the square of the depth... in metric units, a 1m wall would have to resist 5000 Newtons of outward force per running meter. A 2m wall would have to resist 4 times the force or 20,000 Newtons per running meter.

Of course the force will be highest at the bottom, decreasing toward the top. To help understand how the force is distributed vertically, the top 1m of our 2m wall will be subjected to 5,000 Newtons per running meter, and the bottom 1m will be subjected to the remainder i.e. 15,000 Newtons per running meter.

You'd want to add in a "fudge factor" to deal with additional forces from wave action, shock loads, etc.. (perhaps 2 or 3 times). "Art" takes over from science when it comes to choosing fudge factors so you have enough strength without overdesigning, but the basic calculations don't require more than high school math... unless you get into irregular shapes, or you are looking to calculate "beam" stresses.

Does this help?

P.S. - Bernd - the english word for "beton" is "concrete".

In reply to Message (14168.3.1.1)

Re: Re: Re: Off Topic: How to build a pool?

By JustAComment - Mon 17/01/05 14:22:44 GMT

Website:

Unfortunately since your dealing with a liquid, downward pressure is not all that you have, with a fluidic compond such as water, pressure will be exerted dependent on depth throughout the structure. So while the highest pressures will be exerted at the bottom of the pool, both downward and sideways, the pressure will decrease as you reach shallower levels. The mathematics invlolved are actually quite complex so I won't get into it, but I'm sure you can get some advice from a retired pool builder, or something like that.

Hope this helps.

In reply to Message (14168.3.1)

Re: Re: Off Topic: How to build a pool?

By Bernd2 - Mon 17/01/05 10:58:08 GMT

Website:

If I remember right, the hydrostatic pressure of the water is only downwards, but dont remember how to calculate the force to the side walls. Schools is over for me since 22 years now. Can anyone help me out with the formula?

I thought about a "in ground" pool about 4 x 6 m (thats about 12 x 18 feet) with a deep from 1,2m (4 feet) then down to 2m (6 feet) and some "roman stairs" at the side.

I am quite good in Beton work, so there is no Problem and I have some very good resources for heavy machinery. I really don´t want to dig this hole by hand.

Best regards

Bernd

In reply to Message (14168.3)

Re: Off Topic: How to build a pool?

By JustAComment - Mon 17/01/05 09:48:25 GMT

Website:

Alright, now this is an interesting question, well you mentioned that 100 cubic meters is allowed in total, so in other words you could buid a pool thats 4.64m wide by 4.64m deep by 4.64m long. Well as another person already said this would be a pritty bug pool but I'm guessing you would'nt go anywhere near this 100 cubic meter limit. Your question regarding the window is a good one and depends at what depth you plan on putting the window as well as the final cubic volume of the pool. Also a 1m x 1m window would be huge and would probably need you to use very thick glass even at a depth of 1 m, but just simply look at the breaking point of certain windows with you dimensions, and see what the pressure is at the depth your looking for. Anyways just wanted to metion this. The other problem is creating the retaining wall, becuase a 100 cubic meter pool would end up weighing 100 tonnes, even if your going with half the size pool you've still got 50 tonnes so that would be a pritty serious retaining wall. Also I know that 50 tonnes is the weight pressing down however I'm sure that regulations state that your wall must support at least 25% of this weight which is still pritty substantial.

Anyways good luck.

In reply to Message (14168)

Off Topic: How to build a pool?

By Bernd2 - Sun 16/01/05 15:14:59 GMT

Website:

Hi all,

I am in the process to buy a house with a quite big garden and I thought it would be a very good idea to build a pool. The local laws allow pools up to 100 cubic meters without permission (oh a miracle...something to build in Germany without a permission!!).

Unfortunatly the house is on a small hill, so my garden is not horizontally, so one wall of the pool would be not in the ground. Actually, thats not the real problem. The problem is, that I have the idea now to install a glas windows in this wall.

I found many recources on the web how to build a pool but none mention the use of glas. Does anyone know how to dimension the glas with a diameter of 1 x 1 m or a bit bigger?

Best regards

Bernd

Report Abuse or Problem to Nigel at Minxmovies
If you enjoy this forum, then please make a small donation to help with running costs: (you can change amount)