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Originally posted by arcwelder76:

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Originally posted by comet24:

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Originally posted by 280nosler:
Does anybody but me wonder how a thin layer of porous concrete (or Portland cement) holds back the water, or how the pressure of the water and weight of the cement for the structure don't collapse into it's self?

I was kinda surprised at that. Was thinking the same thing.


Guy uses one simple tool but films it was a decent camera gear, edits it and uploads it.

Concrete is porous, yes. But we've successfully built plenty of dams out of it.

That isn't a lot of water, and concrete is very strong.

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Originally posted by Tommydogg:
Watched it all the way to the end to see if there was a purpose. Well?

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Originally posted by Tommydogg:
Watched it all the way to the end to see if there was a purpose. Well?

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Originally posted by 280nosler:
I understand that, but dams are also 10-12 feet thick at their highest point with the lowest stress level, and use engineered steel reinforcement, and built into bedrock. This dude slaps some cement on some bamboo and all of a sudden 1/4 inch of cement is waterproof? Bullshit. At an estimated 5 feet deep, the water is creating little over 2.1 psi, and while an aluminum wall pool can handle it (because it is semi flexible) concrete is not, and at the thickness shown, any flex would crack.

Secondly, for anybody that has worked in cement/ concrete, you would know that the pH in concrete handling it that way (without gloves) would literally eat your hands. When wet, cement and concrete have a pH if about 13, meaning any significant exposure to such an alkaline would do serious damage (in part because your hands are slightly acidic). At very least that is not concrete he is spreading, at the very most this is a highly edited video.