The Seasteading Institute

I’d think with a larger structure you may be able to use foamed-concrete instead of polystyrene to fill air-cavities and create positive-buoyancy and thus unsinkability. Thing is, the more weight being supported, […]

I think I’ve figured out a way to build large concrete half-spheres manufactured on the ocean itself. Eliminates the need for a dry-dock, but probably would require at least a water-based crane.

Ehhh, your picture link didn’t work.
 
But I doubt you’d have much success with dish-soap. I’m not sure what foaming agent is actually used to make foamed concrete. As a guess, what you want to make a porous […]

The problem with pillars is that they tend toward rocking and rolling motions and because of this are rather uncomfortable.
You see them in oil rig designs because they are working vessels, not comfort vessels, […]