ThothX Tower: 20 km, inflatable, freestanding structure complete with an electrical elevator

[fcu45]

It is Canadian Patent,

Would it be possible to have such 20 km freestanding structure?
Inflatable as mentioned in the news, what about the wind load and the sway!!!

http://www.theguardian.com/science/2015/aug/17/space-elevator-thothx-tower

 

[btrueblood]

"actively guided over its base"

Doesn't say exactly how that would be done, though.

 

[Lomarandil]

It doesn't need to be possible to launch a crowdfunding campaign...

 

[JStephen]

I'm trying to think why they'd need to patent this. Is somebody else gonna steal their idea and build their own 20km structure or what?

 

[JStephen]

On the Thoth website, they give the patent number, and you can look up the patent online for more details.

Basically, he proposes to make a tube 230m diameter, with the tube walls composed of smaller diameter (0.5 to 1 m, if I read it correctly) tubes aligned lengthwise made of superdy-strong material pressurized to 1,400 bar to keep them in tension. The "active guidance" comes from gyroscopes and from varying tube pressure as required. The superdy-strong material is 1.4 cm boron or Kevlar or whatever. Maybe the Superman's cape material. Anyway, it's pressurized, but not inflated like a balloon. Looks like wind loading hasn't really been considered in any detail. Nor is elastic stability, for that matter.

I haven't priced boron out per pound, and suspect the inventor hasn't either. But it looks like about 1.3 million tons of it required, fabricated. So if anyone's got a million tons of scrap boron tubes laying around, this might be a good way to put them to use.

Reading through it all is a lot like reading about the Starship Enterprise, where it is all made to sound entirely reasonable except for the minor detail that the whole thing is just fantasy on the face of it. Obviously, a lot of time went into thinking of all this, but they should have gotten a good sci-fi story out of it instead of spending money to patent it. Which, come to think of it, I can't imagine why anyone spent money to patent it.

 

[fcu45]

Thanks JStephen for the informative post.

The news does not seem consider this topic as a since fiction these days, in fact space elevator is being discussed as if it is the next step into human-space journey!!!

Even there are news of Google involvement in such idea...

It might be a trillion dollars or more project, imagine a firm getting share due to such patent ....


A tube of 230 m dia. Would be facing considrable lateral loads, wind and seismic, and generates an amazing moment near the base, as well as along the structure.

a 1 kN at 10 km height, that is 10,000 kN.m moment !!!

 

[JStephen]

Looking at that a little more-
He's assuming a 229m ID and 230m OD with straight divider plates between OD and ID.
If you replace that with tubes 0.5m diameter instead of the "square" cross section, that's working off a design hoop stress of around 360,000 PSI.
Elsewhere, I find boron fibers made by putting boron on tungsten can have strengths up to 600,000 psi. So I assume that's where he's getting that from.
But basically, if you had the capability to build that, the heck with building it, you could make oodles of money by making a whole lot of other things first.