jeriendhal | FYS: Updated Ring Size

Okay, going by

cdk's suggestions, I'm going to increase the radius of the Ring to a nice even 100,000 km. This gives us a circumference of 628,318 km and allows the 1,000 km width I'd wanted without putting a permanent sunshade over the Earth. Total surface area counting oceans works out to a roomy 628 million sq km, not counting an approximately 10 km thick base for ocean depth and infrastructure.

As far as gravity goes, ignoring the mass of the Ring itself (since I have no idea what it would be) the rotational speed to maintain 1G would be 112,736 km/hr, making a full rotation around the Earth around ten times an hour. Which means, if it wasn't obvious before, the Ring is going to have to built of some kind of Unobtainium to hold together at that velocity.

As a side note, that definitely means the space elevators can't be physically connected to the Ring. I imagine there's some kind of anchoring platforms connected magnetically to the Roof, like a titanic maglev train. Moving people and cargo from the elevator's top and accelerating them to match the speed of the Ring's rotation would be pretty impressive.

Even more impressive would be how the Ring got moving that fast in the first place. I think it would involve a lot of ion engines running for a long time.