New material enables 1,000-meter super-skyscrapers

The Register ^ | 18 June 2013 | Rik Myslewski

[ShadowAce]

A Finnish company says that it has solved a problem that has vexed the designers of ultra-tall skyscrapers such as the 828-meter Burj Khalifa in Dubai or the 509-meter Taipei 101 in Taiwan – and we'll pause for a moment to let you guess what that problem might be.

Ready? It's the fact that elevators are currently limited to a maximum travel distance of around 500 meters. The Burj Khalifa, in fact, has an elevator that holds the world record for the longest travel distance: 504m (1,654 feet).

And what's keeping elevators from exceeding that limit? Time for another pause for reflection, dear Reg reader. Okay, now give yourself a gold star if you identified the limiting factor as the weight of the steel cable, known in the elevator trade as the rope.

Kone, a global elevator and escalator company headquartered in Espoo, Finland, has introduced what it immodestly calls UltraRope, which it claims will enable skyscraper elevators to rise as high as 1,000 meters in a single trip.

Kone provides some rather staggering stats about steel rope versus its UltraRope. For example, at a building height of 500 meters and with an elevator large enough to hold two-dozen souls, the total mass in motion of a steel rope-hoisted lift system would be 29,000 kilograms. The same system equipped with UltraRope would total a mere 12,800 kilograms.

There's a lot of heavy
lifting needed to lift a lift

That's impressive enough, but if you extend that building height to 800 meters, the steel-rope weight would increase to 108,600 kilograms, while the UltraRope-based lift system would rise only to 13,900 kilograms.

That weight savings would result in a 15 per cent reduction in energy consumption for a 500-meter elevator, Kone claims, and a 45 per cent reduction should your elevator ride be 800 meters.

What's more, Kone says that UltraRope will last "at least twice" as long as conventional steel rope, is highly resistant to wear and abrasion, and requires no lubrication.

UltraRope's secret? That versatile über-material carbon fiber; or, as Kone explains, "a carbon fiber core and a unique high-friction coating" – and it's not revealing exactly what that "unique" coating is made of.

Kone also says that UltraRope is less susceptible to being affected by building sway caused by high winds because "carbon fiber resonates at a completely different frequency to steel and most other building materials." Since conventional steel-roped elevators sometimes need to be shut down when swaying affects them, score this one "advantage, UltraRope."

"The benefits of KONE UltraRope versus conventional elevator hoisting technologies are numerous and indisputable," says Kone president and CEO Matti Alahuhta.

Those benefits are going to be needed in the near future, seeing as how more than half of the Earth's seven-plus billion souls now live in cities – and that urbanization is accelerating. This presents an eco-friendly opportunity for Kone, the company says, because "building upwards is seen as the sustainable urban solution."

There are more and more tall buildings being built, and the tallest are getting taller. "Nearly 600 buildings of 200 meters or more are currently under construction or planned to be built over the next few years, according to the Council on Tall Buildings and Urban Habitat," says Kone, citing the organization that just wrapped up its "tall building event of the year" in London.

There are currently only three elevator-equipped structures in the world that top 500 meters – the two mentioned above plus Toronto, Ontario's 553-meter CN Tower – and only the Burj Khalifa has a 500-meter elevator. However, Kone notes that 20 more over-500 meter buildings are currently in the planning stages, and if UltraRope catches on you may be able to reach those new buildings' top floors without having to stop and switch into a second-stage elevator as you now need to do in many a tall building.

Now if they can only do something about that ear-popping pressure change. ®

[Gay State Conservative]

I’ve been to the top of the Burj Khalifa.Not really the top...the highest public observation deck (above which are private apartments).It wasn’t nearly as impressive as was the roof deck of the WTC or the observation deck at the ESB.All you see from the Burj is a few other modern buildings and then sand.Lots and lots of sand!

[thackney]

A real answer to your first question:

Why Can’t We Start Building The World’s Deepest Building?
http://www.forbes.com/sites/quora/2013/02/11/why-cant-we-start-building-the-worlds-deepest-building/

More expensive and less desirable.

[Technocrat]

Ooo Ooo! Algebra time
X = weight of rope
Y = weight of car
X+Y=12800
1.6X+Y=13900 (60% more length)

so

.6X = 1100
X = 1800 or so
which is 3.6 Kg/M
(Which seems more reasonable)

[thackney]

Keep in mind as the rope gets longer, it has to have more strength, so it has more material per meter.

[Rich21IE]

I don’t know; I’d have thought the further you get from the earths core, the less the gravity so the lighter everything gets.

[j. earl carter]

RE: why doesn't elevator have a motor on the car

I think elevators usually use a counterweight, so that when the car goes up, the counterweight goes down. That way, only the weight of passengers is being lifted, not the weight of the car. This setup naturally puts the motor on the roof of the building.

[Red Badger]

More and different problems require more and different solutions.

“Everything is theoretically impossible, until it is done.” Robert Heinlein........

[G Larry]

I’ve been on the 55th floor of an office building....in the second bank of elevators...(only 825 ft.)
(and Sydney Tower, which I believe is 1000 ft.)

I have no interest in being in an office 3000 feet up!
(or more)

Do you?

[ShadowAce]

Do you?

Not for about 11.5 years now.

[G Larry]

Over that distance, the quality of the graffiti should be better.....

[LoneRangerMassachusetts]

I’d quibble a bit with the implied premise that changing elevators is such an absolute deal breaker. Speaking personally, I think I’d find it kind of a cool thing to do.

could simply transfer to the next tier elevator every 500 meters. At 4 meters per story that is every 125 stories.

[Red Badger]

Quality vs Quantity...............

[2 Kool 2 Be 4-Gotten]

Arguably not *ideal* but the article would have you believe that’s a absolute deal-breaker whereas I think it might be perceived as kind of cool and a definite conversation starter.

[thackney]

Technically feasible doesn’t mean worthwhile or economically competitive. I don’t mean to say we cannot do it. I am saying there isn’t a good reason to do so.

[GreenHornet]

Whether you build below or above ground, the elevator problem is the same.

Yeah, I know.......that damn elevator music!

[Technocrat]

Oh drat. Now I need another data point :)

[jimt]

That’s an excellent reason. Another is simply cost. To move a counterweighted elevator, you need only enough power to overcome inertia and any weight imbalance. Otherwise you’d need the power to overcome inertia PLUS the weight - a significant increase - 4 or 5 times the counterweighted version.

[Ole Okie]

Why don’t the engineers just use magnetic levitation for elevators?

Toshiba has developed a permanent magnet/electromagnet method to keep the elevator from touching the guide rails. It has nothing to do with vertical levitation.

I vote we fall back on "Beam me up, Scotty."

[USFRIENDINVICTORIA]

"Why dont elevators have gears along the shaft, and an electric motor on the car itself? (no rope)"

Some do. These "traction elevators" are essentially vertical funicular railways.

This building ("One Wall Centre" in Vancouver) has traction elevators.

[TangoLimaSierra]

serious question: Why dont elevators have gears along the shaft, and an electric motor on the car itself? (no rope)

Exactly what I was about to post. That's why I always read all the comments before I post. Someone usually has already beat me to it.