Underground concrete water tank, help!

[Smithson]

We've been building an underground tank with the help of some locals. Turned out to be no nearly strong enough and one of the walls collapsed. I'm now looking at options for doing it and need some advice. I also need to reinforce the existing walls.

It is 1m deep x 1.4m wide x 9.6m long. Can we use breeze block for the walls with poured columns every 2.4m?

[DrAndy]

Can we use breeze block for the walls with poured columns every 2.4m?

nope, the water pressure would be too much; you essentially have to build it like a swimming pool, lots of iron and a good vibrated pour, all at once

if you did use blocks, the walls would need to be fully supported on the outside too, maybe lots of packed sand. You would have to be certain it would not move and leave the walls unprotected

[palexxxx]

Can we use breeze block for the walls with poured columns every 2.4m?

if you did use blocks, the walls would need to be fully supported on the outside too, maybe lots of packed sand. You would have to be certain it would not move and leave the walls unprotected

But this construction is going to be underground, therefor the surrounding earth should be fairly good 'support', shouldn't it?

[superman]

I have a basement room made from poured concrete, measuring 15m x 4m. Mine leaks water in, or did, during the wet season. Reason it leaks is cuz the joints leak. When making a concrete underground tank you need to have rubber seals in cold joints put into the construction to stop leakage. A builder of swimming pools is your best bet. http://waterstopindia.com/pdf/Chap%2...Waterstops.pdf

[DrAndy]

But this construction is going to be underground, therefor the surrounding earth should be fairly good 'support', shouldn't it?

as I said, if you packed sand around you may support the walls, but it would still leak probably

[FarangRed]

I was going to say did you put a water stop in? also in the base did you put steel?

[Looper]

one of the walls collapsed

Post a photo so we can see the shape but it sounds like it is rectangular?

Since shape is not a concern from an aesthetic perspective best to go for an integrally strong shape.

A vertical cyclinder is good. That is why kiddies paddling pools are round and not square, so that the modest strength of the materials can do the job of holding the water by distributing the pressure forces evenly in the structure.

[DrAndy]

It is 1m deep x 1.4m wide x 9.6m long

but it sounds like it is rectangular?

A vertical cyclinder is good.

yes, good point; a round one would be better and stronger

[Looper]

I have 2 underground water tanks 50m3 and 30m3.

Both cylinders. But the concrete is also reinforced and very thick.

You can park a 2 tonne 4 wheely on the circular lid of the tank.

[VocalNeal]

Is space a constraint? I notice yours is long and narrow.

Your volume is about 13 cubic metres.

I would think simply burying standard Isaan earthenware water storage pots would suffice? They are about 2m spheres.so you'll need 3. Locals are familiar with them so should be able to work it all out. You'll need to join them together but that also is "local" blue pipe.

Dig the hole 1/2m oversize plus room for working around the joining pipes. Then backfill with sand. The key is the ground should be "virgin" so stable and they must be full before you backfill.

OR
How to Build an Underground Brick Dome Water Tank - Howtopedia - english

[baby maker]

Noticed one thing not mentioned is a aquiseal solution to add to the mix when constructing....negates sepage.
The product is sold here in Thailand....can't remember the brand....sure it's not a problem.

Would second the advice on around tank....if site allows....
though the Thais are no strangers to building rectangular tanks for domestic holding of fish...see them in villages everywhere.

[Smithson]

Thanks for the replies. The tank is for soaking bamboo, hence the strange dimensions. we're now doing it simular to a pool, except without as much steel and not pouring as thick. Steel square spacing will be 200mm and the concrete 70mm thick. Any thoughts?

[baby maker]

the concrete 70mm thick. Any thoughts?

,,,,walls look light to me....only 3 inches thick if I understand you correctly...
look into that Aquiseal.....a big problem with local pours, is that they aren't viberated...
as pours are in the West.

[Smithson]

We have a plastic liner so I'm not concerned about leaks. My concern is strength, especially when it's empty with someone inside, last thing I want is it to come crashing down on them. We have used water proving agent in cement.