sand by strapping and brackets

lumber treatment use borax and engine oil. Soak some boards in borax for a week then mix 20-30% gas with engine oil The borax stops termites oil stops dry rot.

the true geopolymer method To make the foundation permanent and completely waterproof, you must mix the water glass with an aluminosilicate precursor—such as fly ash, metakaolin (reactive clay), or ground slag—along with an alkaline activator like sodium hydroxide (lye). This triggers a full polycondensation chemical reaction, creating a highly crystalline, ceramic-like binder that will never dissolve in water

dig the footprint Dig 15 shallow pockets (or a continuous trench) into the sand directly beneath where the 15 ground nodes of your 14-foot dome will rest

mix the batch Create a geopolymer concrete mix by volume:• 75% to 80% Local Sand (The aggregate). • 20% to 25% Fly Ash / Metakaolin / Ground Slag (The binder matrix). • Activating Liquid: A premixed solution of liquid sodium silicate (water glass) and a small amount of sodium hydroxide (lye).

pour and cure Pour the wet slurry into your dug-out pockets, level the surfaces completely, and keep them covered with plastic while they set. True geopolymers cure rapidly at ambient temperatures, forming ultra-hard mineral anchors within days

4x4 timbers Even with a rock-hard geopolymer pad, you should still use your pressure-treated 4x4s as a sill plate rather than bolting the EMT conduit directly to the stone. • The Hybrid Approach: Lay the geopolymer pads in the sand, place the 4x4 timber ring on top of them, and drive heavy concrete anchors (like Tapcons or sleeve anchors) through the 4x4s straight down into the geopolymer blocks. • The Benefit: The geopolymer prevents the 4x4s from sinking or tilting in the shifting sand, while the 4x4 timbers give you a forgiving surface to drill, shift, and adjust your hubless EMT base ring nodes during final assembly.