Space Rocket Re-Usable as Space Base Building Blocks

[therocketjohn]

It seems every space rocket has a cylindrical fuel tank design. Because of this shape, it seems very difficult to re-use parts of the space rocket for space station parts. Is there any reason a rocket couldn't be built using rectangular instead of cylindrical design so that the space rocket tank and parts could be re-used for moon base or space station building blocks? This way, fuel tank recovery missions could be eliminated and space rated parts could be used long term for space station and/or moon base walls, floors, and ceilings.

 

[kg]

I recall that a "wet workshop" was one of the original concepts for sky lab. http://en.wikipedia.org/wiki/Wet_workshop
I am going out on a limb here but I think they build the fuel tanks for rockets to be as light as possible and able to hold the high pressure contents. Maybe this is why they are the shape that they are? As far as could a rocket fly if it's cross section were square or triangular, I don't know.

 

[thnkrx]

A decade or so back, there was a serious proposal put forth by space advocates regarding the Titan II missiles being scrapped after the cold war: convert them to Titan III's and turn the upper stages into space station components. There were literally thousands of these things; in theory they could have put a *lot* of space station building blocks into orbit, possibly patterned after the old MOLE (Manned Orbiting Laboratory) from the 60's.