SMF Construction Process

> > Good point. The material for the torus must resist that. Perhaps
the
> > solution is to make the pressure skin thicker so as to resist the
> > force of straightening out.
> >
> Well, yes. But that is the very problem. You do not want any
bending
> moments in a pressure vessel. You want pressure vessel walls
loaded in
> pure tension. A pressure vessel like a bent pipe has a large
shear
> stress, this is generally prohibited. Materials are much weaker
in bending
> than in tension. Making the walls much thicker is a major
weight
> penalty It is a lot lighter if you stick to a conventional design
loaded in
> pure tension.

The concerns you raise here are the ones that were bothering me
about the Stanford Torus and the glass "roof."

I'm left very confused about how a glass roof, basically covering
1/2 the circumference of the torus ring is fine, especially
considering the stresses at the juncture of the glass and the metal,
but a curving torus constructed entirely of metal will weaken under
the stresses.

As a laymen, this seems backwards to me. Can someone take a few
minutes and explain why the glass isn't a weak point but the metal
curvature is.

If a thicker skin is a solution, why not build that worker-station,
pressurize it, inhabit it, get the refinery working, and then take
blocks of metal and using vapor disposition start applying vaporized
metal to the station skin. The questions that this process raises
for me are 1.) the atmospheric stresses you reference in this post
will be present, so what does the application of more metal to a
stressed pressure vessel do to the distribution of forces and
stresses; 2.) thermal expansion issues; 3.) a solid monolithic metal
shell sprayed onto a pressure vessel composed of many parts joined
together with welds - what forces and transformations occur at the
point of contact?