This looks good to me??
http://www.wimp.com/concretetents/

I like these yurts
http://www.yurts.com/default.aspx

My first thought was, Could this be used to fashion a reasonably lasting low cost hangar? Then I found some prices. Looks like $30K just for the type of structure they demonstrate.

But for a solid, totally unpractical recreation tent, these are unmatched!

By the appearance of the video, it appears to be marketed to military operations...

I'm guessing even a Twin Otter might even be a bit small to haul one of these babies into the backcountry!

When I met Wife 3, her house was an all concrete house, except for the ceiling and roof. It didn't take too long to figure out that there are some real downsides to a concrete house, and I suspect many of the same downsides would exist with a "concrete tent". The major one is that it's hard has heck to heat, although once heated, it tends to hold the heat pretty well. At least her house had large south-facing windows, to take advantage of winter sun, but I don't see that with the concrete tent.

Interesting, though--I'll give it that.

Cary