Dear Romain,
Corrugated galvanised iron or steel (colloquially corrugated iron or pailing (in Caribbean English), occasionally abbreviated CGI) is a building material composed of sheets of hot-dip galvanised mild steel, cold-rolled to produce a linear corrugated pattern in them. The corrugations increase the bending strength of the sheet in the direction perpendicular to the corrugations, but not parallel to them. Normally each sheet is manufactured longer in its strong direction.
So far the technical background!
CGI is lightweight and easily transported. It was and still is widely used especially in rural and military buildings such as sheds and water tanks. Its unique properties were used in the development of countries like Australia from the 1840s, and it is still helping developing countries today. Despite its widespread use, it rusts very easily and can produce an undesirable aesthetic appearance.
So, historically, it could have been used in WW2 in the Russian hemisphere.
However, you are right: a tank will seldomly be parked in a shed, unless there is a need to hide it or protect it during maintenance, where weather could be a big hampering.
Otherwise: the steel is outside and the flesh in!!
Take care about yourself and enjoy the weekend.
So, Christian, tell us more about your idea!
Cheers,
P.