does it have the compressive strength as structural concrete ?
Is it suitable for spraying on the outside of a geodesic dome home?
Spraycrete or gunnite as show can meet any building code for strength, equal to or crater than block. Best when a mono filiment or metal fiber sometimes little over 1" long are used in the mix, providing reinforcing instead of wire mesh. Sometimes sprayed over an inflated balloon or shaped wire mesh structure in shape desired, using frames for doors and windows or cut out and trimmed out for them later.
If done over sprayed polyurethane foam insulation in appropriate thickness (normally over 2" it will provide Code approved Fire barrier when over plastic insulation. Structures with urethane foam and spray-crete can provide the best structurally sound, wind proof and insulation (biggest issue is air exchange) you can install.
Best if a solvent base primer to prevent free lime in the 'crete' from attacking the elastomeric coatings from back side are applied over the spary crete: system is> one coat of primer, two-three coats of elastomeric coating, then a finish coat of pure acrylic latex paint to keep dirt from clinging to elastomeric material .
(noting that NO pva, vinyl fillers and NO plastisizing agents in elastomeric)Should be a 25 dry mil thickness for the finished system as minimum, using Porter Paint 6000 as reference guide.
Dome Home, system of ball0on, sprayed with urethane foam insulation (thickness determined by insulation required), plus spray crete at 2"+, plus elastomeric system on outside of balloon, with 2" of spraycrete on the inside of balloon (normally requires pins/ wire mesh to mechanically attach to smooth surface after balloon is deflated (can reuse or be left in place) makes a dynamite home or 'anything' with spans achievable from residential to commercial airplane hanger sizes being achievable. davzway
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.
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