I built a Rubb shelter to use as a workshop for genset overhaul, they're fun - definitely need a crane to hold the first section in place and to lift the covering, the one we had required a timber ring beam on top of the concrete pad and the covering, doors etc. were sized accordingly. We also had use of a bigger one a couple of years later as a vehicle workshop. They're very resistant to UV and if you have the optional liner, quite easy to heat in the winter.I'd guess there not cheap and probably bigger than you need but I think that Rubb build the deployable aircraft hangars and associated buildings for the MOD.
They might be able to point you in the right direction if they don't do what you need.
Aircraft hangars | Rubb UK
Rubb semi-permanent and permanent, custom-designed aircraft hangars are used by airports, airlines, and military orgs across the world.www.rubbuk.com
Another alternative is to make a frame and cover it with linen spot stuck to the poles, coat this with cellulose dope and the linen absorbs it and stiffems it and tensions it up, strong, waterproof and light.
What do you mean "only one tree" There are plenty of trees there the only problem is that they are all in Norway.Can remember being up your way and the farmer was welding some thick wire into loops. Asking what for he said he was burying sleepers in the ground with the wire loops on they were going to be attached to the caravan to stop it blowing away!
Only one tree up there and it's in the middle of the high street you must get some wind surprised 4" plastic holds up to it.
The only problem is weight, needs a substantial frame to hold it and good foundations.
You can use Shotcrete instead of cement as this is much stronger and structural with the correct grade.
It doesn't seem to need that much of a frame (I'm still in the "experimental stage" of my build).
Each layer acts as a support for the next, and it'll be much lighter than a brick building of the same dimensions.
I'm using garden trampoline frames, with 75x10x3 weldmesh, to make a 10ftx7ftx30ft "concrete polytunnel".
I've never heard of "shot Crete". I shall investigate...
No...You've actually started your shelter build then?
No...
No...
Is that a double negative then?
I was hoping for pics of a Stig Of The Dump like shelter.
Available for free but buyer must collect ...good luckBet the Yanks left a few decent ones in Kabul. Doors open and lights still on.