Plastic welding with steel wool

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demographic
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Re: Plastic welding with steel wool

Post by demographic »

On about concrete, if you look at a concrete lintel its got the steel re-bar in the bottom where its under tension, which means it holds it so the top (all concrete bit) is under compression during usage.

Some concrete also has fibres mixed in which lessens cracks propagation as well as the reinforcing bars that it usually has.
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Yorick
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Re: Plastic welding with steel wool

Post by Yorick »

demographic wrote: Wed Jul 26, 2023 7:56 pm On about concrete, if you look at a concrete lintel its got the steel re-bar in the bottom where its under tension, which means it holds it so the top (all concrete bit) is under compression during usage.

Some concrete also has fibres mixed in which lessens cracks propagation as well as the reinforcing bars that it usually has.
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Mr. Dazzle
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Re: Plastic welding with steel wool

Post by Mr. Dazzle »

demographic wrote: Wed Jul 26, 2023 7:56 pm Some concrete also has fibres mixed in which lessens cracks propagation as well as the reinforcing bars that it usually has.
Yaaknooow....now that you say that, I do wonder if the CFRP reinforced concrete bridges here in MK actually have carbon fibres in the matrix, so in the cement that is. It would make some sense 'cause you'd wanna warn people of that fact before they tried working on it with 'normal' concrete methods :think: Maybe that's what the signs are about.

Re: Lintels...I've recently had a pizza oven come BBQ stand built in my garden out of bricks and lintels. The lintels have steel bars right in the middle, rather than off to one side as you say and as I expected. Wassat about then? Is it just so you can't put them in upside down by mistake?
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Re: Plastic welding with steel wool

Post by Rockburner »

Mr. Dazzle wrote: Wed Jul 26, 2023 9:08 pm Wassat about then? Is it just so you can't put them in upside down by mistake?
That would be my guess. You can guarantee that any "This way down" signage/notices on the lintel would end up pointing in every direction except down.
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