OK now these are probably not affordable or available to civilians, but it looks like a hasty way to build a concrete shelter. Given a bit more time and a lot less $$$, I'm betting the DIY'er could do something like this with a shotcrete gun. Sourcing the airform could still be rather pricey.
On a smaller scale but similar to the grain storage silos used in Iraq. I worked in the bulk weighing industry for over 20 years and we had contracts with Iraq to supply and install electronic weighing systems. The Iraqi wouldn't allow photos of anything but the structures were very much like these
Depends on if it provides same protection level as real concrete & the amount of earth it can take being put over/on it. But its damn interesting. Too bad their US supplier don't have a website that I can find just for curiosity about price.
A simple effective way to build a similiar structure but much stronger is to build a mound of dirt, cover with plastic, install wire mesh, and cover with concrete. Once set the dirt is excavated and you have a very strong storm proof structure. Concrete saw any openings needed, install wiring/etc, and move in. Cover with more plastic after double water proffing, add insulation, and cover with earth to any depth and you have a fallout shelter.
Monolithic domes Lay down foundation, install inflation ring Install form Inflate form Go inside and blow about 6 to 8 inches of urethane foam Install rebar Go back inside and blow in shotcrete. Finish inside to taste, move in. Cost nearlyt he same as stick built./ See <cite>www.[B]monolithic[/B].com/</cite> for photos, stories and prices. These guys have been around for decades. Very well tested product. Fun fotos.