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I am making a 2” slab of concrete for DIY 45 lb weight plate.

I have some extra aluminum window screen that I’m not using. I was thinking of putting some strips of window screen into the concrete midway to make it stronger.

You think this is a good idea?

I would “just try it out” but I don’t have a backyard to do many trials of concrete and am going to have to do this when I find the time and place.

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    What purpose will this slab serve? It could be relevant.
    – isherwood
    Feb 14, 2023 at 22:21
  • DIY 45 lb weight plate Feb 14, 2023 at 22:28
  • I would use Chicken wire mesh
    – Traveler
    Feb 14, 2023 at 23:31
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    Go to an actual masonry supplier, or the internet, as I don't think you'll find these at a big box, and get a bag of reinforcing fibers for concrete. As noted by MTA, aluminum will destroy your concrete, not reinforce it.
    – Ecnerwal
    Feb 15, 2023 at 3:39
  • OP could look at fiberglass mesh, I've seen it used successfully for reinforcing things like countertops. Feb 17, 2023 at 9:15

3 Answers 3

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I don't think so. Screen will almost act like a divider in the concrete. You won't get good aggregate pass-through. Even if you agitate the mix enough to get the loose cement through, you're essentially creating planes with no strengthening aggregate in them. You're almost better off with no reinforcement.

That's just my edjumacated hunch, though.

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    He's certainly better off with no reinforcement, not "almost". A very fine mesh is going to have about as much adhesion to the surrounding cement as a sheet of paper would. As you say, it will block any aggregate from passing through and create a massive shear weakness. And if any water ever gets in there (it will), the concrete will spall right off the mesh.
    – TooTea
    Feb 16, 2023 at 8:44
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    Moreover, the thermal expansion of aluminum is very different from the concrete. So it will create stress (which will lead to cracks),when the temperature change. It doesn't happen for reinforced concrete because steel happens to have a similar expansion coefficient as concrete (luckily).
    – dim
    Feb 16, 2023 at 12:53
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Aluminum is attacked by the alkali in concrete. The reaction gives off hydrogen gas.

There is a research paper, Corrosion of Embedded Material Other Than Reinforcing Steel (PDF) published by the R&D Labs of the Portland Cement Association. It includes reports of failure and spalling of concrete from embedded aluminum.

Not a good idea!

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That type of mesh is never used for strengthening concrete. I believe the only think you will accomplish by adding that mesh is divesting yourself of the mesh.

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