A thought for those intending to use some random mix of sand/crushed granite/rocks.
If a "perfect" mix of different sizes is to make such a big difference to the ultimate strength of the E/G, there needs to be some method of checking if the mix we have in front of us is good/bad/indifferent.
Could this be a dry check of the density ?
Take a small box of known dimensions. Fill it with the largest size rocks and weigh it. This will give me the lowest "density" of my E/G( I'm ignoring the weight of the epoxy for simplicity.)
If I now pour in smaller rocks, shaking the box as I do so, till I can get no more to go in below the rim, and weigh again, this gives me an improved "density".
Now I pour in another smaller sized fill, and repeat the process.
I can, by this method, see what I can make with a mix of segregated, and known sizes of fill particles.
If I now take a "random" mix of crushed stones and pour it into the box, shaking it as I do so, the weight/density figure will give me a check on how good a particular sample is. Pushing it a bit, it might let me see if the mix could be improved with an addition of some particular size, but I'm not sure if that's worth considering. I'd need to separate the "random" mix through a set of seives to see how the size distribution was.
What I'm looking for is a simple method of checking that I'm starting with the best mix from whatever is available to me locally.
Thoughts ?
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