tori (spokes)

I don't think the mass of spoke shielding is that much of a problem
if we're shielding the entire colony. Why not make the spokes
work/office areas? Penthouse apartments? Also remember that the
effective weight goes down as the gravity lessens. At the higher
levels, the shielding doesn't add much to the tension at all, since
the things are holding the entire torus together!

One difference is that I've taken the concrete hull idea to be the
baseline. The advantages are myriad & great.
This means that we are in fact spinning the entire ~2 meter shield,
and it is the colony hull.
Another thing to keep in mind is that the spokes aren't keeping the
spinning mass of the colony from flying off tangentially into space:
The rim of the torus is and must be -at a minimum- capable of
sustaining the tension forces of holding up the mass at 1G.
This alters our thinking to something more like the Ringworld of
(somewhat soft) S.F. The Ring in the novel required a substance with
a tensile strength near the shear strength of the strong atomic
binding force, but for our torus, steel cables will do very well,
with a good safety factor.
Thus, the mathematics of the torus are like those of a suspension
bridge with no endpoints. As Mark wrote, the spokes are for access,
and simply holding things together (as well as the spinning torus
stability problems noted for the Ringworld -no, we won't use attitude
jets to keep the ring from hitting the Sun -er, hub.)
Now the question of shielding mass on the spokes (and the lessened
'weight' at higher levels) changes drastically. Are the spokes held
up by tension or are they structures under compression, resting on
the torus? Probably both, so the tension is at its greatest at the
middle, and they have very little effective mass resting on the floor
of the torus.

Thinking of bicycle spokes, I thought of something wierd... Notice
how bicycle spokes don't run radially from the hub to the rim. They
run from the edge of the hub, tangentially out to the rim.
For a torus colony, how might this work? The gravity in the spokes
wouldn't pull you straight down the spokes, but at an anglee (not
that you'd notice it).
One thing this would do is make the inside of the spoke a slide...
Run cable cars down them. A luge run! (the 'sleds' they run in the
Olympics at extremely high speeds!)
More wierd yet, make the spokes spiral down, so as you slide down,
the acceleration from centrifugal force goes up, but the slope angle
gets less. Your sled shoots out at the torus floor and runs level
across the floor.

Al Globus wrote:
>> There's a problem with tori I hadn't thought of: to minimize
shielding mass you need to wrap the spokes in shielding. That means
they need to rotate. At increases the structural strength
requirements of the spokes immensely. Of course, you could have the
torus spin inside a stationary cylindrical shielding mass, but then,
why not make a thin cylinder?

Mark Collins wrote:
> From what I understand of the Stanford Torus design the spokes have
3 functions.
> 1. Structural strength for the Torus (stiffening to help keep it's
shape with differential loading due to mass distribution of
internal structures)
> 2. Access for power feeds and heat exchange to outside radiators.
> 3. Human access to the torus itself.
>
> Since human occupation of the spokes would be minimal I don't think
they need shielding. If shielding was required couldn't a shielded
elevator type affair suffice for the minimal time people would
spend in there?