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Infinitely strong cantilever
2

Infinitely strong cantilever

RE: Infinitely strong cantilever

"will be supported by steel beams ".  So contact your local steel warehouse/ fabricator.

The shadow appears to show cross braces between the inner and outer walls.  My guess is the beams would be much deeper than shown in the rendering.  No reason they couldn't put big knee braces below it if they so desired.

The article mentions 72,000,000 lbs capacity.  I suspect this should be 72,000 lbs.

So be studying up on those curved beam equations...(see that thread in the FEA forum).

RE: Infinitely strong cantilever

Its the new anti-gravity paint that they will use on the guardrails.

RE: Infinitely strong cantilever

120 people, lets say 50,000 lbs
uniformly distributed on a ring, 70' radius
centroid is about 50'
so the bending moment at the cliff is 2.5Mft.lbs
supported by two I-beams (of very large size) ...

how about cable trusses above the platform ?

RE: Infinitely strong cantilever

Nah, the contractor just put some extra toenails in that thing.  Don't worry, that'll hold it.

RE: Infinitely strong cantilever

quote:
The project is still seeking an insurer, said architect David Jin, who said he came up with the skywalk idea while visiting the canyon in 1996.

do we need to add anything more?

RE: Infinitely strong cantilever

(OP)
Thought that might bring a chuckle to a few informed people.  

Just when you think one of your designs may be a bit hokey... this will always serve as a baseline of hokeyness... lol

DRW

RE: Infinitely strong cantilever

interesting.  typical architect's concept that has a very thin section and a sky hook.

RE: Infinitely strong cantilever

It's a bit of a challenge... but if you make the guardrails composite with the concrete and beef them up a tad... just a matter of doing the sums...  You don't, however, want to use diagonal struts... they would have a tendency to cause the track to pull out from the cliff face... <G>

Dik

RE: Infinitely strong cantilever

Environmentally speaking - it is an outrage. Visual pollution. If you want thrills, try base jumping. Maybe the Hualapi nation should try building a casino, out of site of the canyon.  I always regarded Native Americans as respecting the Earth, but that idea is idiotic.

RE: Infinitely strong cantilever

Isn't the solution obvious?  They just need to place a couple of skyhooks at the end!

One of my mentors always used to say if it doesn't 'look right' then it probably isn't, and the proposed structure, as pictured, just doesn't look right to me.

The knee-braced solution may spoil the view through the 'glass' bottom, so I expect they'll end up with a cable-stayed structure, which will look good anyway.

RE: Infinitely strong cantilever

Uh...sacrebleu...every building ever built is visual pollution when you really get down to it...Dallas actually looked a whole lot better when it was all pasture, I'll bet...

RE: Infinitely strong cantilever

I say lets use invisible cables!

Regards,
Lutfi

RE: Infinitely strong cantilever

Lutfi... they don't make very good compression elements <G>...

Dik

RE: Infinitely strong cantilever

ah but they'd be in tension, off the skyhook you see.

RE: Infinitely strong cantilever

(OP)
All these skyhooks sound like a novel solution... but one would need a hell of a skyhook to support the 72 million pounds... it would have to be one of the strongest skyhooks ever made... it may even warrant upgrading to a moonhook.

they must like safety fators out there, because it would be in the order of 3000 or so.

I would pay 25 bucks in a heartbeat to see how they can support 72 million pounds with a cantilever 70 feet long.

RE: Infinitely strong cantilever

From a different website, I find an extra paragraph inserted in the story, to read:

"Las Vegas-based architect David Jin came up with the idea for the skywalk in 1996 during a trip to the Canyon.

He teamed up with Lochsa Engineering, also from Las Vegas, whose portfolio includes Mandalay Bay Hotel and Hard Rock Hotel."

IE, those of you wishing to get involved on the project are too late!

Personally, I think they should omit the glass walls, and in fact, not even put up a handrail.  Just a 5' wide sidewalk out into space.  That would be cool.

RE: Infinitely strong cantilever

SMCADMAN...
The concrete would have to be transparent... not transluscent... else we would see it!

DRW75... that would be an SG0714 sky hook... the 713 is about 8% shy...

Dik (quibbling, again)

RE: Infinitely strong cantilever

Bet it will sing like a tuning fork when the wind blows through it.
What a great place NOT to have something like that.
MHO

pennpoint

RE: Infinitely strong cantilever

The frequency would be too high... the SG0714 has a very short length, not the the 814... with that one, you would likely have vibration issues... <G>

Dik

RE: Infinitely strong cantilever

JStephen...
I meant it is appalling to spoil the beauty of the Canyon with this absurdity...build it in Las Vegas, maybe off the Stratosphere Tower. They can demo the entire Main Street below, which is nothing but a haven for drug deals and prostitution anyway, and build a replica of the Canyon there.

RE: Infinitely strong cantilever

someone will design it as a cable stayed/suspension bridge-type structure, I bet.  hopefully there will be more articles so we can see how the project progresses.

RE: Infinitely strong cantilever

I agree with the idea of not giving any hand rails. Just not using anything that is visible and the transparent track zig-zags through the space (horse-shoe shape is a dud idea). Not knowing, where to put your next step... that will be fun.

Ciao.

RE: Infinitely strong cantilever

Personally, I would build it from Unobtainium:

Elastic Modulus: 10E99 Pa
Density: 0.00 kg/m^3
Yield Strength: 10E99 Pa
Coefficient of Thermal Expansion: 0.00 /K

It is one of the library of standard materials in my finite element analysis package - comes in really handy when I am having deflection or stress concentration problems using ordinary materials like steel, aluminium, tungsten, titanium, etc.

(However, I have found that most of the metal merchants in my region have very limited stocks.)

RE: Infinitely strong cantilever

(However, I have found that most of the metal merchants in my region have very limited stocks.)

You have to go to the specialist dealers, the ones that sell sky hook always have a large supply of unobtainium  in stock.

RE: Infinitely strong cantilever

They clearly just need a huge permanent magnet underneath the structure, maybe on the wall face.  Then they'll have to design for maybe 25% of the load.

Then, maybe they could use hollow sections, and fill them up with compressed hydrogen.  

Hell, you wouldn't even have to design them at all.  You may have to design something that will hold them DOWN.

:)

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