OK, so we place an interlocking joint front and back, something simple to keep steel rods from being jammed down into the works. (The equivalent of derailing trains.)
The flow from each pump is distributed into a few dozen 8-14 inch diameter soft-walled cups (like a hovercraft skirt). The cups are distributed equally on left and right sides, and staggered along the slide path.
A series of panels runs parallel, each at increments of 5 mph (or more), to a top speed of 25 mph (will cut my current commute time on city buses in half).
The circular track is flattened to give two parallel oppositely-directed sets of tracks (lanes). Only the ends open out, close the loop, and slabs get cycled back in (or diverted off for service). Run another track at right angles.
Do we need rotating panels (like bearings) between succesive "speed lanes", not to allow for reduced friction, but to allow someone not athletic to step on and get more gently accelerated to the next lane speed? There would of course be "bearing followers", which would be travelling at half the speed, and would not have you facing the wrong way when you got to the other lane... so may be not necessary.
Brian, I would assume the thixotropic mix would only serve to increase friction, and the "spraying up between slabs" would disappear with the interlocking stuff front and back. The limit of 1 gpm per "cup" would decrease any tendency to spray, but the soft skirt would more than overcome this. So the leading and trailing edges would need to be tapered a bit to vent that off before alignment under a crack.
At night, all but lower speed belts could be shut down.
Linear drives could thrust the slabs above it, and could probably be placed every block or so, depending on how many people get on and off at concentrated locations. Since every installation will be following grade, some of the linear induction motors would actually be removing kinetic energy from the slab above it, and place that power back on the DC bus the other drives draw from.
Handrails? USA-OSHA would say yes...
Is this better than a bus or tram? Could you have such a system, that had beat cops or "transit security personnel" spaced along it? Asimov's future had relatively few people in it...
David A. Smith