On Fri, 11 Jun 2021 20:45:02 +0000, god posted for all of us to digest...


I'm seeing these all over now, and they are calling them Wpg-slabs. Seriously, though, as a structural engineer, I wanted to flesh this out, as it is a primary return on google. These are called waffle slabs, and they have been used for this application all along. They usually use something like a plastic bucket as a form
(https://www.geoplastglobal.com/en/pr...labs/skydome/). Floatation is an issue with both the form voids and your hay. Your settlement is much higher with the waffle voids made of "hay" (straw) than if they were soil, but you design the slab to span the void. Using hay in scenarios like this is somewhat common, but not for
careful formwork as you describe. The main reason is that hay has zero lateral pressure, so you can temporarily fill a void (it will decay) without a temporary condition with substantial earth retention pressures when casting structural concrete slabs, where it is a big no-no to leave that as a void. I was here looking for what
vermicide to add.

Add more reinforcing use rebar instead of mesh.

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Tekkie