Very interesting, I recently came across this little ship design for a WWII carrier design.
Project Habbakuk
"The Habbakuk, as proposed to Winston Churchill by Lord Mountbatten and Geoffrey Pyke, was to be approximately 2,000 feet long (600 m) and have a
displacement of an amazing 2,000,000 tons or more, constructed in Canada from 280,000 blocks of ice (later changed to a mixture of ice and wood pulp
known as Pykrete after Pyke, who proposed the Habbakuk project — the material was invented by others). The ship's deep draft would have kept it out
of most harbours. Inside the vessel, protected by 50-foot-thick walls, a refrigeration plant would maintain the structure against melting. The ship
would have extremely limited maneuverability, but was expected to be capable of up to 10 knots (18 km/h) using 26 electric drive motors mounted in
separate external nacelles. Its armaments would have included 40 dual-barrelled 4.5" DP (dual-purpose) turrets and numerous light anti-aircraft guns,
and it would have housed an airstrip and up to 150 twin-engined bombers or fighters."
Wikipedia Link to IceBerg ship
The material "pykrete" is supposedly close to concrete in strength. A pretty impressive material, too bad it was cancelled when convential means of
fighting had turned the tide of the war and other projects had diverted funds from building the ships.
Shattered OUT...