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gobug | Posted in Green Products and Materials on

Thin shell concrete structures and ferrocement have been an interest of mine for years. I used flyash in all my recipes. 

Do you use any Portland cement?  What ratios of flyash, Portland and aggregate.? What grit aggregate?

What ratio would you suggest, specifically for a floating raft foundation?

What formulation of flyash do you suggest? I have used type F, even though it is a special order item. 

Thanks in advance.

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  1. user-6184358 | | #1

    Here is a good modern reference -- Making Better Concrete: Guidelines to Using Fly Ash for Higher-Quality, Eco-Friendly Structures by Bruce King
    You need to work with you ready mix supplier to see what the offer.

    1. gobug | | #2

      Thanks Tim.
      Due to my remote location, I will have to order dry mix and add water on site. That will enable me to add some basalt fiber and if needed the flyash as well. I did visit the supplier years ago and they seem flexible.
      I appreciate the reference.

  2. Expert Member

    You are aiming for a 32 MPA mix for a slab on grade foundation. Your supplier should be able to give the proportions of fly-ash, etc. you can add to achieve that. Designing concrete mixes isn't really a DIY activity.

  3. nickdefabrizio | | #4

    As I have stated in other posts, I love concrete as a material but think we need to use less of it for residential building due to climate concerns. One way to do that is to use thin shell in place of thicker pours where alternatives to concrete are not feasible. I am curious, how thin have you gone with slabs/floors that need to support furniture and people and how was it done?

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