back to article New material enables 1,000-meter super-skyscrapers

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 …

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  1. Anonymous Coward
    Joke

    So in the race to build the tallest elevator we have reached the Finnish line?

    You're a great audience! I'm here all week!!

    1. cortland

      Re: So in the race to build the tallest elevator we have reached the Finnish line?

      I think they've lapped you.

  2. Yet Another Anonymous coward Silver badge

    Any rope is the problem

    The limit on skyscrapers is how many lifts you have and how long people are prepared to wait for them.

    If you have a rope, however ultra, you are limited to one lift per shaft.

    A shaft takes up floor space, adding shafts means less tenants.

    The solution is maglev lifts than run on rails in the walls of the shaft so you can have multiple lifts in the same shaft. You can also queue them like tube trains on the circle line. So in the morning rush, after the first lift leaves the ground floor there is another one that was parked in the basement which can follow it up a few seconds later.

    You do need a bit of software to make sure that destination for lift 1 is > destination for lift 2 but even VB programmers should be able to manage that.

    1. Jolyon Smith
      Joke

      Re: Any rope is the problem

      I think you are dangerously over-estimating the capabilities of VB programmers. ;)

      1. Fatman
        FAIL

        Re: I think you are dangerously over-estimating the capabilities of VB programmers. ;)

        I would extend that to include any Microsoft Technology in critical applications.

        After all, I would not want to be in such an elevator when its control computer running Windows for Smart BuildingsTM decides it is time to download its "Patch Tuesday" updates with their inevitable reboot.

        I can imagine it now, you are heading to the top of a very tall building, when the intercom announces: "The control computer must restart to complete the updates. Your elevator cab may either freeze in place, or go into free fall. When the system reboots, control will resume."

        Thus you begin your 7 minutes of terror. ( http://www.youtube.com/watch?v=kQ_8Md4iK-o )

    2. Steven Roper
      Thumb Up

      Re: Any rope is the problem

      Well, the next step up from that is what Star Trek euphemistically referred to as "turbolifts".

      Once you replace the old Otis rope-and-counterweight system with a rail-based one (even if it's only a rack-and-pinion type rail drive rather than a maglev) it becomes possible to construct points and sidings by which lifts can be shunted and routed around each other. This would save on shaft space by allowing multiple lifts to occupy the same track while still having the possibility of passing each other by swapping rails at the points as needed.

      Of course the downside of any rail-driven lift system is power consumption, because you now have to have an engine on the lift car itself driving the car against gravity. This is why the rope-and-counterweight system was invented in the first place - the counterweight means that the only force that has to be overcome is the inertia of the lift car, counterweight and rope - only the difference between the car and counterweight has to be hauled against gravity. (Note that Earth's gravity counts for quite a lot of power; it's the equivalent of going from 0 - 100 km/h in 2.8 seconds, continuously.)

      With modern technology, however, the power consumption increase inherent in using a rack-and-pinion driven lift could be offset by using the same regenerative braking system used in electric cars. A lift could generate energy on the way down, by using its gravitational downward motion to charge a battery via its motor-generators. This energy can then be re-used for the upward trip; the entropic loss can easily be made up via a live rail and hot shoe system delivering extra power to the lift. I'd be interested to see what the difference in power use for such a system would be compared to the traditional rope-and-counterweight system. Any engineers care to comment?

      With a system like this, there'd be no theoretical limit to the height of the shaft either, other than whatever structural compression limits might obtain on the materials used to construct the shaft and the building itself.

      1. Charles 9

        Re: Any rope is the problem

        What about failsafes? The Otis system used the presence of the rope itself to hold back safety bars, more modern systems rely on a governor to engage brake shoes on the rope or motor, and hydraulic elevators use the hydraulic system itself to limit the rate of descent. How would you ensure the safety of untethered elevator cars in the event of a catastrophic failure?

        1. Steve Knox

          Re: Any rope is the problem

          @Steven Roper: Of course the downside of any rail-driven lift system is power consumption, because you now have to have an engine on the lift car itself driving the car against gravity.

          Not if the engine is in the rails.

          @Charles 9: ...more modern systems rely on a governor to engage brake shoes on the rope or motor...

          Not according to http://science.howstuffworks.com/science-vs-myth/everyday-myths/question730.htm -- modern failsafe brakes engage the rails in the shaft. An untethered car could use the same system with little modification.

          1. Michael H.F. Wilkinson Silver badge
            Joke

            Re: Any rope is the problem

            Enter the Heisenberg/Schrödinger elevator. It tunnels to the correct destination, and allows an arbitrary (but uncertain) number of elevators per shaft. Add defocused temporal perception and they will be there before you know you want them.

            The only downside is their tendency to sulk in basements.

            1. Elmer Phud

              Re: Any rope is the problem

              Yeah but . . . .

              If there's Heisenberg in it then how do you know they are in the basement?

              Won't it also never arrive as the more you are waiting for it the more unlikely it is to arrive at the floor you are on.

              (which means they are already operating under the H/S system)

            2. Number6

              Re: Any rope is the problem

              Enter the Heisenberg/Schrödinger elevator.

              Isn't that one where you don't know whether the occupants of the lift car are dead or alive until you open the door? Instead of something radioactive in the lift to determine the state, you just need to make sure one of the passengers is prone to flatulence.

          2. Charles 9

            Re: Any rope is the problem

            "Not according to http://science.howstuffworks.com/science-vs-myth/everyday-myths/question730.htm -- modern failsafe brakes engage the rails in the shaft. An untethered car could use the same system with little modification."

            That assumes a power failure or similar problem with the car. But there's another point of failure that hasn't been fully accommodated yet: a break in the rail, particularly one simultaneous with a disaster. Especially for a cable-free design, there needs to be a way for the car to be able to support itself in the event of a single- or possible dual-rail failure (a cable-free setup would probably need four rails for safety and redundancy), because in the system you describe, the safety brake might have nothing to engage: slipping off or jumping the broken rail. That's one reason cables and counterweights are still in use: they are the failsafe against a rail failure. And since they rely on physics, it's a bulky by physically simple design. If an elevator car broke free of the guide rails, the setup would still mean the motor could retard or perhaps direct the movement of the car to a controlled point for extraction.

        2. Wzrd1 Silver badge

          Re: Any rope is the problem

          Failsafes would be simple. A centrifugal system that, when a predetermined velocity is reached, signals a fall and engages brakes on a rail system that guides the elevator.

      2. Anonymous Coward
        Anonymous Coward

        Re: Any rope is the problem

        And the next step up from a turbolift is the Wonkavator.

        "Willy Wonka: No, it's a Wonkavator. An elevator can only go up and down, but the Wonkavator can go sideways, and slantways, and longways, and backways...

        Charlie Bucket: And frontways?

        Willy Wonka: ...and squareways, and front ways, and any other ways that you can think of. It can take you to any room in the whole factory just by pressing one of these buttons. Any of these buttons. Just press a button, and *zing*! You're off. "

        1. Anonymous Coward
          Anonymous Coward

          Re: Any rope is the problem

          ""Willy Wonka: No, it's a Wonkavator. An elevator can only go up and down, but the Wonkavator can go sideways, and slantways, and longways, and backways..."

          I have had a dream several times where a lift behaves like that.

          In the back of my mind the seed is a customer site's lift system many years ago. I can't pin the experience down - somewhere in England. The lifts had been added to a rabbit warren of adjoining buildings that were only a few floors high.There was definitely something unexpected about the way their lifts travelled. My feeling is that they paused and rotated 90 degrees laterally at some point to get the entrance aligned for another floor's layout. A strange feeling in an enclosed space.

          1. NomNomNom

            Re: Any rope is the problem

            Why don't you just use the stairs you lazy fucks?

            1. John 62

              Re: Any rope is the problem

              I'm reasonably fit, but after about 150 steps I'd be needing a rest and potentially a shower before starting work.

      3. zooooooom

        Re: Any rope is the problem

        "This is why the rope-and-counterweight system was invented in the first place - the counterweight means that the only force that has to be overcome is the inertia of"

        Yeah - but the irrelevence of the lift comapred to the cable is the point of TFA. All you're really looking for is a handy way to store your potential energy for recycling to recover this.

      4. Wzrd1 Silver badge

        Re: Any rope is the problem

        The problem with magnetic systems is the immense amount of electrical energy required to move the load. Elevators are far from light, they do have to endure the stresses of carrying their cargo, be it human or furniture/equipment.

        That massive amount of current needed to shift an elevator car ends up producing immense amounts of heat, requiring cooling and further adding to the already massive electrical load of the system. Indeed, it could easily use more energy than the entire office tower occupants needs.

        Great idea, thought of it myself, briefly. However, our current technology limits such magnetic devices quite heavily.

        1. Frumious Bandersnatch

          Re: Any rope is the problem

          That massive amount of current needed to shift an elevator car ends up producing immense amounts of heat

          Well if there's that much hot air, why not tether a hot air balloon to the lift and use that to lift the cargo? You'd have to have the balloon "outside the box" (ie the building) which would definitely lead to challenges on windy days, but at least you might be able to use other waste heat from the building to keep it topped up. Sounds much nicer if you take the gondola to the 50th floor instead of a regular old "lift".

    3. 142
      Thumb Up

      @Yet Another Anonymous coward

      you sound like a man who's played as much SimTower as I have!

    4. Justin Stringfellow
      FAIL

      Re: Any rope is the problem

      "a bit of software" is understating it.

      Q. What happens, once lift 1 and 2 have reached their destination, take on new occupants, and they want to travel in conflicting directions?

      The answer needs to bear in mind that you're not building a vertical train set. You need to leave room in the building for the stuff that the building was built for.

      1. Banjo M
        Boffin

        "What happens, once lift 1 and 2 have reached their destination..."

        Then they get queued. If there are other destinations that can reached during the wait then they can be. Some people would have to wait longer than other to travel less far but Yet Another Anonymous coward’s comment suggests a higher aggregated throughput.

        It has its flaws but so do current lifts, I’m sure we’ve all had a lift stop at nearly every floor when we were in a rush.

        1. Naughtyhorse

          Re: "What happens, once lift 1 and 2 have reached their destination..."

          yeah - cos taking 6 lifts to get to the 123rd floor is what the modern skyscraper is all about.

          while you are waiting maybe you's like to hear my pitch for a confectionery based hot beverage maker......

      2. Annihilator
        Boffin

        Re: Any rope is the problem

        "Q. What happens, once lift 1 and 2 have reached their destination, take on new occupants, and they want to travel in conflicting directions?"

        Pretty simple and has already been piloted. Replace the "call" button on each floor with a keypad - instead of entering the floor you want when you're in the lift, you press it and wait for a lift to be scheduled. Allows for much more efficient lift routing.

        1. JeeBee

          Re: Any rope is the problem

          We have that in our building, so it's well beyond "piloted".

        2. Fatman

          Re: Replace the "call" button on each floor with a keypad -

          Which is something already done in practice.

          read more: ( http://www.smartplanet.com/blog/pure-genius/intelligent-elevators-answer-vertical-challenges/8191 )

          1. xperroni
            FAIL

            Re: Replace the "call" button on each floor with a keypad -

            This is how elevators work at the building where our company is hosted. It certainly adds a degree of amusement to the office routine every now and again, whenever a first-timer rushes into an elevator, turns to where the button panel should be, and stares in dismay at the blank wall they find instead.

            Unfortunately its scheduling algorithm is pure pants. Time and again we've been at the hall waiting for a lift, and when an elevator arrives, it is directed to a single floor directly above ours. In come two or three people, leaving the remaining twelve or so to wonder why the damned thing couldn't be programmed to make a stop or two before its final destination.

            Alas, I just hope the failsafe brakes at least aren't software-controlled!

            1. Daniel B.
              Boffin

              Re: Replace the "call" button on each floor with a keypad -

              Heh. I've been at 3 buildings where this system is in use. Fair warning to y'all guys: each one of you riding on the elevator must key in the destination. The system will route you, but will only count one person. If you don't do that, it's pretty possible you'll get assigned to the one lift where there's only room for one more person, and the rest will have to wait. Or, you'll end up stopping at places where lots of people are waiting the lift.

              At least there was a good feature in these: if the elevator gets actually overloaded, it will no longer stop anywhere but the actual destination of the people inside. W00t!

      3. Magnus_Pym

        Re: Any rope is the problem

        "Q. What happens, once lift 1 and 2 have reached their destination, take on new occupants, and they want to travel in conflicting directions?"

        A: Same as with a train line. You have a up line and a down line. In this case an up shaft and down shaft. At each floor there is a connecting horizontal 'shaft' that between the up and down. It's only along the horizontal part that the doors open.

        The car goes up the up shaft to the correct floor, stops and moves along the horizontal shaft to where the doors are. Doors open occupants change. The doors close and the car move along again into either the up or the down shaft and travels on. Routing software makes sure that two cars don't try to occupy the same bit of shaft at the same time and optimises travel.

        Having said that. I don't think I'd like to use one.

      4. JeeBee
        Pint

        Re: Any rope is the problem

        You have an "UP" shaft and a "DOWN" shaft.

        But lifts can still break, and one stuck lift could mean a whole series of lift cars behind it being blocked. This means you need a bypass mechanism - points, sidings, etc.

        Effectly you turn (for example) 8 lift shafts with one car into two lift shafts up, two down, each with multiple cars. The space for the other shafts is used for "turbo" to high floors and bypass shafts. It would look like a vertical railway.

        But the points would be interesting to implement ... maybe four up, four down and if a lift sticks, bad luck.

        1. Elmer Phud

          Re: Any rope is the problem

          "You have an "UP" shaft and a "DOWN" shaft."

          Aren't they 'Paternoster' lifts?

      5. James Micallef Silver badge
        Thumb Up

        Re: Any rope is the problem

        "Q. What happens, once lift 1 and 2 have reached their destination, take on new occupants, and they want to travel in conflicting directions?

        The answer needs to bear in mind that you're not building a vertical train set."

        Well, actually the answer IS to build a vertical train set. Have 1 shaft of elevators that only go up, 1 shaft only down, and rooms in the ceiling and basement where cabins are moved from one shaft to the other.

      6. Wzrd1 Silver badge

        Re: Any rope is the problem

        That was part of my thoughts, add in that the more likely place to build such a tram would be on the outside of the building, obliterating the possibility of a decent view through a window. Add in the significant incline to ascend a floor, it becomes highly problematic.

      7. Naughtyhorse

        Re: Any rope is the problem

        the answer to that is easy....

        He didnt think it out that far.

        must be a VB programmer :-)

    5. monkeyfish

      Re: Any rope is the problem

      So what if lift 1 reaches floor 105, and lift 2 is on floor 58. Then the person who gets into lift 1 what to go to floor 1, whereas the person getting in to lift 2 want to go the top? Does lift 1 have to go the top floor before it can go down again?

      Could possibly have a system where the lifts roll over at the top and bottom, so that shaft A goes up and shaft B comes down. Just better make sure no-ones in the lift when it rolls over at the top (or at least normal non-thrill seaking people that didn't want to weren't anyway).

      1. Banjo M
        Thumb Up

        Re: Any rope is the problem

        “So what if lift 1 reaches floor 105, and lift 2 is on floor 58. Then the person who gets into lift 1 what to go to floor 1, whereas the person getting in to lift 2 want to go the top? Does lift 1 have to go the top floor before it can go down again?”

        Yes. But a single lift in a shaft has a similar problem as a single lift can’t go to the top and to the bottom at the same time. The multi-lift shaft lift will be able to deliver more people whilst this detour is happening. And if there aren’t many other people travelling you would probably have ‘parked’ a lift in the basement waiting for the next ground-floor rush.

        (p.s. the downvote wasn't me)

      2. J.G.Harston Silver badge

        Re: Any rope is the problem

        That's called a Paternoster lift, as in Sheffield's University's Tower of Art Arts Tower. This type of lift is probably so named as you recite the Pater Noster as you step off the edge...

      3. Kubla Cant

        Re: Any rope is the problem

        the lifts roll over at the top and bottom

        This is what a Paternoster lift does. Going over the top is disappointingly un-thrilling, but then it has to be slow enough for people to get in while it's in motion.

      4. Anonymous Coward
        Anonymous Coward

        Re: Any rope is the problem

        "Just better make sure no-ones in the lift when it rolls over at the top"

        There are continuous "bucket" lift systems where you step in and out as the next unit arrives. In theory they have failsafe mechanisms if someone stays on them beyond the top level. A university had a tragic accident when the failsafe didn't work.

        1. Anonymous Coward
          Anonymous Coward

          Re: Any rope is the problem

          I can report that, although strongly discouraged, it is perfectly possible to ride around the top and the bottom of a paternoster without being crushed or falling out. Never announce to your mates on the outside that you are about to do this, as they will invariably hit the emergency stop button while you are going around the dark bit at the bottom. Then you have to explain to the building maintenance people why you ignored the warning signs.

    6. fandom

      Re: Any rope is the problem

      "If you have a rope, however ultra, you are limited to one lift per shaft."

      Not really, I think it is in the Petronas Towers where they have two lifts per shaft, one of top of the other, one for the even numbered floors and one for the odd numbered ones.

      In the lobby there are mechanical stairs that they people to the first floor so they can get to the odd numbered floors.

      1. Anonymous Coward
        Anonymous Coward

        Re: Any rope is the problem

        Same system is used in one of the salt mines in Poland that you can visit.

      2. Steve Knox

        Re: Any rope is the problem

        Not really, I think it is in the Petronas Towers where they have two lifts per shaft, one of top of the other, one for the even numbered floors and one for the odd numbered ones.

        Technically, that would be one lift with either two cars or one car with two cargo bays, depending on exactly how it's constructed.

        Multiple lifts implies independent movement, which is not possible with that arrangement.

    7. This post has been deleted by its author

    8. GrumpyOldBloke

      Re: Any rope is the problem

      Not quite ready to throw away the rope - especially at todays energy prices. If your concern is that there can only be one car per shaft then there is no reason that the upper car(s) can't have a vertical tube through which pass the ropes of the cars below. It means the ropes would attach to cars a little off centre wasting energy on the rails but that would surely be less energy than hauling the entire weight of the elevator around without a counterweight. As for the lift 1, lift 2 ... lift n scenarios; destination call key pads would help but it would have to be accepted that there would be traffic patterns where all cars could not be used. Alternately an aggressive system of acceleration and deceleration coupled with trapdoors in the tops and bottoms of the cars could allow them to exchange their contents - or less aggressively a Russian doll type system.

      Modeling could to be used to determine whether the extra complexity of multiple cars per shaft was worthwhile - perhaps a VB program. However, given that such systems are rare (non existent?) it may be that the extra complexity of multiple cars per shaft is not worth the benefit and it is easier to train people to stagger their usage.

  3. asdf

    hmm

    Here in the west many don't know just what an amazing accomplishment Burj Khalifa is. Nearly 700 ft taller than any other man made structure including radio towers which don't even have fancy elevators and fire extinguishers and all that jazz. Yes many western companies help build it and yes it a screaming example of just how carried away Dubai got with the checkbook which it will be paying off for generations. Still the only the thing more amazing to me than this building is the fact Alain Robert has already climbed it.

    1. Alan 6

      Re: hmm

      There are many problems with the construction of tall towers that people just don't consider, and many of them are down to Pointy Haired Boss.

      A few years ago I was working on a project in a tower in London, planning the CCTV installation, there were 1000 cameras in and around the building, needing to store 60 days standard def footage at a mixture of 12.5 and 25fps, we're talking over 1pb of capacity here, around 16tb a day, with RAID 6 redundancy it's a lot of storage.

      Then the CEO of the building's owners decides he'd like a mirror of the live feeds in his office close to the top floor, and he'd also like mirrored storage up there as well.

      Problem #1 there was absolutely no capacity in the cable ducts for a new fibre for the amount of data that would need to be zoomed up the the top floors, so we had to run an 8-core armoured fibre down the lift shafts and hope for the best, and #2 the system that we'd just spent almost £100k on didn't allow for mirrored recording, and he was insistant, so we ripped that out, spent £250k on a new system and my boss had £100k worth of CCTV recording kit he could sell to someone else...

    2. Anonymous Coward
      Anonymous Coward

      Re: hmm

      "it a screaming example of just how carried away Dubai got with the checkbook which it will be paying off for generations. "

      What, like Japan, the UK, and most of Southern Europe? They've already had a "restructuring" of the debt on the Dubai World group, so somebody had a haircut of sorts, however you dress it up, and Abu Dhabi have bailed out the Dubai government.

      So long as Abu Dhabi continue to backstop (and ultimately payoff) the Dubai debt, there's no problem. I doubt very much that Dubai can payoff the debt itself. If Abu Dhabi decide they don't want to be on the hook, then Dubai's debt goes pop, and the ultimate lenders take the hit. Who lent the money in th first place? I've no idea, but I'm sure the vermin at RBS have managed to ensure I'm on the hook for some of it.

      1. John 62

        Re: hmm

        Indeed, it was supposed to be the Burj Dubai until the money ran out and Abu Dhabi stepped in with a bailout and got the name changed to Burj Khalifa after Sheik Khalifa, ruler of Abu Dhabi and the UAE. Sheik Mohammed of Dubai still has his picture everywhere in the visitor centre, though.

        Also, at the top you'd think they would use a waterless urinal, like they use in Ikea, since it takes a lot of energy to get water up there, but they use a US-style urinal that uses a US gallon per flush. Granted there's only one urinal for visitors, but even so, that's a lot of water being pumped up just to be flushed away again. Though, I'm not an expert so maybe there's some fancy system I don't know about that means it's easier/cheaper for them to have what seems to be a wasteful urinal than a waterless one.

  4. asdf

    just to troll

    Skyscrapers hell where is my space elevator? We need cables 100's km long not a thousand meters.

    1. Anomalous Cowshed

      Re: just to troll

      For that we will need...nanotube!

      1. James Micallef Silver badge
        Happy

        Re: "nanotube"

        "Nanotube!!"

        To be explained loudly in the same musical fashion as "Monorail"

    2. John Smith 19 Gold badge
      Unhappy

      Re: just to troll

      "Skyscrapers hell where is my space elevator? We need cables 100's km long not a thousand meters."

      No, sorry, not even close.

      Proponents of space elevators seem rather coy about the numbers needed for the material because the current SoA is so far below what's needed, although (slowly) they are climbing, no pun intended.

      IIRC the standard unit of rope capability for a space elevator is called a "Uri."

      1. hplasm
        Happy

        Re: Uri

        As in Gagarin, or Geller?

        1. Silverburn
          Thumb Up

          Re: Uri

          Geller. Because while the science lags behind expectations, they still have to make shit up and sell it to the public as real.

  5. Kevin McMurtrie Silver badge

    Climber

    It seems like when you're at the point of 30 megagram cables you want the elevator to instead climb a track. The lack of a counter weight would be a lesser disadvantage than the inertial mass of so much cabling.

  6. the spectacularly refined chap

    So how does this enable super-skyscrapers?

    This has been a "limit" for a long time. I remember a couple of years after 9/11 I was drinking with a FOAF (along with the friend) who claimed to have been to been to the World Trade Center while it was still standing. I called bullshit because a) I had been there and b) his comments concerning the lifts ("They're really fast and take you straight to the top") were bull on so many levels, not least you had to take at least two lifts to the top. Anyone who ever watched Escape From New York could have told you exactly the same thing.

    Yes, it's a nice development and interesting, but it's not as if it has been a real limit on height.

    1. graeme leggett Silver badge

      Re: So how does this enable super-skyscrapers?

      A valid point, people think nothing of changing between escalators or lines on the tubes but put them in a vertical situation and they get funny about it. Does having to change lifts spoil the prestige of working on floor 205?

      perhaps the engineering limits on lifts throws up the absurdity of commuting an extra third of a mile to get up to your office.

    2. David Black
      FAIL

      Re: So how does this enable super-skyscrapers?

      Yeah, good call on the "bull":

      http://www.youtube.com/watch?v=JOgqSkiEWdU

  7. Ken Y-N
    Alert

    What about Tokyo Skytree?

    You say "There are currently only three elevator-equipped structures in the world that top 500 meters"

    The Tokyo Skytree is over 500 metres tall (634 metres to be exact) and the lifts take you up to the 350 metre high main deck in a 464.4 metre run, according to Toshiba Elevator's web site. It only takes you 50 seconds to get there, so they do run at a fair, err, nip.

    1. John Smith 19 Gold badge
      Joke

      Re: What about Tokyo Skytree?

      " "There are currently only three elevator-equipped structures in the world that top 500 meters""

      See that's what happens when you use Wikipedia for research.

    2. Alan_Peery
      WTF?

      Re: the lifts take you up to the 350 metre high main deck in a 464.4 metre run

      Do these elevators start underground?

  8. Rex di Bona
    Happy

    looping elevators

    To overcome the lack of cars in an elevator shaft you build two shafts, one for the cars to go up in, and one they come down in. They can be attached in a chain like arrangement, so it's an "all stops" affair. All the cars move one floor at a time. When a car arrives at the top it moves across to the "down shaft" and now moves down to the basement again (No, the car doesn't need to turn upside down ;-) only the movement mechanism needs do that, the car can "rotate" so it's always the one way up.

    This was the original design for an elevator system. It's problems include the time taken is proportional to the number of floors traveled, and you can't easily block off floors. But it does provide for a much larger volume of traffic.

    1. Allan George Dyer
      Alert

      Re: looping elevators

      Sometimes called the paternoster, with open cars so you can jump on and off. Runs continuously, but generally thought to be too dangerous nowadays. That was the only reason I went into the Arts Tower in Sheffield.

      I guess you could have really nasty accidents with a 500m paternoster, that cable isn't going to stop quickly for anything.

      1. Magnus_Pym

        Re: looping elevators

        Loughborough Tech as it was once known. Great answer to an age old problem. Very little real danger. Unfortunately the perceived danger meant that it was too often on stop when some irresponsible students* played games. Not very fast though.

        * all of us and some lecturers.

      2. Elmer Phud

        Re: looping elevators

        Paternosters are prone to 'bloody stupid git' syndrome.

        Builders and scaffold boards or step ladders have been known to forget about the bit tat is outside the box.

        At a hospital near me a builder made that mistake but even the hospital was unable to replace his crushed head.

        They're not there anymore- a shame 'cos they were fun when visiting people.

    2. JeeBee
      FAIL

      Re: looping elevators

      Yeah, like I want a 30 minute ride on an enclosed claustrophobic Big Wheel when I get to work every morning.

    3. Anonymous Coward
      Anonymous Coward

      Re: looping elevators

      wheelchair users need not apply

  9. Anonymous Coward
    Anonymous Coward

    "unique"

    The anti-friction coating is made of babies. Tons and tons of soft, unique little babies.

  10. John Tserkezis

    Before you read on, see if you can guess how the new stuff will be used

    I say Penis Enlargement.

    Along the lines of Idiocracy, it's more likely that technology is going to be used for that, rather than something actually useful.

    1. Anonymous Coward
      Anonymous Coward

      Re: Before you read on, see if you can guess how the new stuff will be used

      Are you sure that would not be useful.

      1. hplasm
        Devil

        Re: Before you read on, see if you can guess how the new stuff will be used

        An extra 500m might be useful- somehow...

  11. Tom 7

    The most fantastic technology in the world to get you into the office faster

    so you can hang around for the boss, who on leaving the unscheduled meeting, will piss off down the golf course, executive lunch.

    Or you could just move into the shard and play football all day in the empty space.

  12. s.d.dongre

    Why cables at all?

    Why not have the lift carriage drive itself? I know i know the counterweight makes it more efficient, but so could an energy harnessing mechanism that stores up energy when the car comes down.

  13. Roger Greenwood
    Happy

    Never mind going up

    It is coming down that is the problem.

    All buildings over say 100 floors need a giant emergency slide. That would be fun.

    And parachutes.

    1. Anonymous Coward
      Linux

      Re: Never mind going up

      Friction burns might be a problem, how about a FLUME instead??

      Penguin natch, they love a good flume ride.

    2. Chris Miller

      Re: Never mind going up

      In the 80s, I was doing some work in the 30-storey Torre Europa* in Madrid. The fire escape method was a flexible tube that you used to drop to the floor below (where there was a similar tube and so on). I imagine (I only saw the pictogram instructions, I never had to use it, thankfully!) that friction slowed you down enough to prevent injury on a 3m drop.

      * The office had a fine view of the neighbouring Bernabéu, which was entertaining when floodlit evening fixtures were being played.

    3. Alan Brown Silver badge

      Re: Never mind going up

      I'd settle for them having working sprinkler systems and tankage.

      Dry risers are only useful to "so high"

  14. John Smith 19 Gold badge
    Boffin

    A note on elevator safety

    In the early 30's the cables went on a lift car in the Empire State Building.

    63 floors straight down.

    With 1 man on board.

    He broke both his legs and probably never got in a lift again but otherwise was completely unharmed.

    Those springs at the bottom of the shaft really do work.

    1. hplasm
      Happy

      Re: A note on elevator safety

      "Those springs at the bottom of the shaft really do work."

      Yes, but it did take an hour for him to finally come to a stop.

      1. Michael Wojcik Silver badge

        Re: A note on elevator safety

        Yes, but it did take an hour for him to finally come to a stop.

        And then he wanted another go. Whee!

    2. Silverburn
      Happy

      Re: A note on elevator safety

      He broke both his legs and probably never got in a lift again but otherwise was completely unharmed

      It would have made a better story if you mentioned "He broke both his legs and probably never got in a lift again but otherwise walked away completely unharmed"

      If you've ever broken a leg, you'd probably realise that "completely unharmed" is somewhat underestimating your injuries.

      1. Anonymous Coward
        Anonymous Coward

        Re: A note on elevator safety

        "If you've ever broken a leg, you'd probably realise that "completely unharmed" is somewhat underestimating your injuries."

        I suspect two broken legs was nothing compared to the lifelong mental trauma from being locked in a box that plummets 63 floors.

        1. Anonymous Coward
          Anonymous Coward

          Re: A note on elevator safety

          And the medical bill you get afterwards. AMERICA!!!!

        2. Charles 9

          Re: A note on elevator safety

          Plus, I believe the survivor was (1) a WOMAN, and (2) the attendant for that elevator (this was before self-service cars were the norm). It happened on a foggy night during World War II, and the cables and safeties all failed because a B-25 (blinded by said fog) managed to fly smack into the building and completely sever the shaft from above, disabling all the safeties. Current theories about how the woman, Betty Lou Oliver, survive range from the mass of cable UNDER the car acting like a spring to the tight fit in the shaft producing a cushion of air under the car that pushed back with increasing pressure as the car fell..

      2. Frumious Bandersnatch

        Re: A note on elevator safety

        If you've ever broken a leg, you'd probably realise that "completely unharmed" is somewhat underestimating your injuries.

        Well, worse things happen on building sites (allegedly).

    3. This post has been deleted by its author

  15. MrPatrick
    Go

    then perhaps you should undertake your civic duty and got and update the page with this new information.

    Then future lazy journalists won't be embarrassed in the same way.

  16. ISYS
    WTF?

    Who makes the lift car?

    Years ago I was in a lift and the plaque on the wall proudly announced that it was supplied by Otis, Reading. I mentioned this to a fellow occupant who told me that there was a company called Schindlers lifts! http://www.schindler.com/com/internet/en/home.html

    1. Anonymous Coward
      Anonymous Coward

      Re: Who makes the lift car?

      I saw these in a hospital which has recently been refurbished. I chortled. Then I went looking to see if their sterlising handwash was called Final Solution.

    2. MJI Silver badge

      Re: Who makes the lift car?

      There was a film about them!

    3. Kubla Cant

      Re: Who makes the lift car?

      While waiting for the lift in a building I was visiting, I read a notice that said it was maintained by The Economical Lift Maintenance Co.

      I decided to take the stairs.

      1. Anonymous Coward
        Anonymous Coward

        Re: Who makes the lift car?

        Of Walla Walla, Washington?

  17. Richie 1
    FAIL

    The numbers are wrong

    When increasing the length from 500m to 800m, the mass of the rope must increase at least linearly (in practise it increases faster than that because you need a thicker rope to hold its own weight).

    So if a 500m UltraRope weighs 12800kg, then an 800m UltraRope must weigh at least 12800 * 800 / 500 = 20480kg. That makes the value 13900kg from the article way too low.

    1. I ain't Spartacus Gold badge

      Re: The numbers are wrong

      The given weight included lift car and a whole bunch of people.

  18. Sceptic Tank Silver badge
    Trollface

    Extra lift.

    "building upwards is seen as the sustainable urban solution."

    Shouldn't having fewer offspring be seen as the sustainable urban solution? Unless a few of these towers topple over once in a while - that'll help.

    Ok, question for the panel: how do mine elevators work? Not in stages AFAIK. [Yes, I did a quick (pictures) check on Wikipedia].

    1. Anonymous Coward
      Anonymous Coward

      Re: Extra lift.

      "Ok, question for the panel: how do mine elevators work? Not in stages AFAIK. "

      (NB, inexpert reply)

      The problem for tall building lifts is weight, space, and building distortion. Now think about the enoromous winding engines above a mine, and you'll see the answer. Mine engineers don't worry about the weight, because they don't have to fit the winding gear in the top of a twelve foot by twelve foot shaft, and they don't worry about the power consumption because they already have a big fat grid connection (or on site generation) rather than having to run the wires up a kilometere of building.

    2. Charles 9

      Re: Extra lift.

      Mine elevators typically work in pairs. As one car goes down from the top, its partner (at the bottom) goes up in sync. The weight of the partner car going up helps to offset the weight of the car going down, reducing the load on the shaft motor. Many times, the partner car also carries an ore load (most car setups have two or three levels for passengers, then an ore carrier on top), further offsetting the descending weight.

    3. NomNomNom

      Re: Extra lift.

      "how do mine elevators work?"

      i don't know, how do your elevators work?

    4. Anonymous Coward
      Anonymous Coward

      Re: Extra lift.

      "how do mine elevators work? Not in stages AFAIK. "

      There was an early mine elevator that consisted of a pole that oscillated vertically - repeatedly moving about 2 metres up and down. It had platforms attached about every 2 metres. In the side of the shaft there were platforms every 2 metres.

      The miners "walked" vertically by stepping onto a moving platform - then off onto a side platform to wait for the next moving one.

      It relied on everyone staying in sync and not missing a beat. The safety record wasn't good when the pole broke near the top.

  19. Silverburn
    Facepalm

    Ropes are so passé.

    Rockets. That's what you want.

    Or even better...a vertical maglev. (aka...rail gun!)

  20. Anonymous Coward
    Anonymous Coward

    beta testers required

    Call me when you get to UltraRope 2.1

  21. Big_Boomer Silver badge
    Trollface

    Why?

    Why do people get so excited about skyscrapers? Penis envy? They are a symptom of the human races ridiculous need to breed continuously until we cover every last square millimeter of the planet, at which point we will become cannibals and probably STILL keep on breeding. The solution is to reduce population, not to change the problem from a 2D to a 3D problem. That said it's not really a 3D problem as without pressurised buildings the upper limit is realistically about 2500 metres ASL. Planes are pressurised at 2500 metres and yes people can live at over 4000 metres but they can't go from sea level to 4000m in a couple of minutes and vice versa every day and not have major health problems. Perhaps as Genesis suggested we need to start selective breeding for shorter people so "They can fit twice as many in the same building site."

    1. Intractable Potsherd
      Joke

      Re: Why?

      Yes, but Human Rights legislation means that you'd never get 'em out by Friday ...

    2. Anonymous Coward
      Anonymous Coward

      Re: Why?

      "That said it's not really a 3D problem as without pressurised buildings the upper limit is realistically about 2500 metres ASL."

      To increase the density you could also extend the building downwards until the temperature became a problem. A bit of lateral thinking like old CRT circuits where the high voltage was negative polarity.

      Richard Branson once proposed that Virgin planes didn't need windows as there was nothing to see for most of the journey. The planes' tv displays would suffice to give passengers something to look at.

  22. Anonymous Coward
    Anonymous Coward

    I note that carbon fibre is mentioned as at least part of the rope make-up. We use steel cables rather than carbon fibre for lift cables for a very good reason. The wear properties of carbon fibre subjected to lateral bearing loads are usually poor compared to steel. (And that applies to all types of carbon fibre, and all weaving patterns.) If carbon fibre needs good wear properties, there will be some glass fibre added to the top layer of a composite panel... however, this works for panels but probably wouldn't work in a rope.

    It's almost definately not really a new material, just a new method of combination of materials in a new continuous process (fabricating over 1km in a single piece) and either:-

    A: It's a flexible carbon/polymer composite, with a *very* carefully designed sheath, possibly fabricated from Kevlar, but maybe even just boring polypropylene, used to prevent fretting of the carbon fibres as it's wound round the drum at the top of the lift shaft. The polymer in the composite in the middle of the rope will be used to prevent the carbon fibres in the rope from fretting against each other. (Be interested to hear how they've reliably acheived that in a flexible but strong piece....)

    OR

    B: Someone is going to be stuck in a lift for several hours one day because the cable frets and breaks, and the automatic safety system prevents them from plummeting to their doom. We can only hope that in those circumstances, the lift roof will be tough enough to withstand 1000m of cable falling on it... with a significant chunk of that length travelling at terminal velocity.

    1. James Hughes 1

      Good God man - you've hit the nail right on the head. I hope these lift rope experts with decades of experience are reading this so they get that clue they so obviously need.

  23. hi_robb
    Joke

    Wow

    I've seen some elevator stories

    but this one is on a different level entirely..

  24. Refugee from Windows

    Boulby Potash Mine

    Has a shaft 1,150m deep and some form of lift in it. Wonder what they use?

  25. Florida1920
    Mushroom

    In a hurry? Take the Dysonvator

    Not for hoovering, mind.

    http://en.wikipedia.org/wiki/Project_Orion_%28nuclear_propulsion%29

  26. Anonymous Coward
    Anonymous Coward

    It's a pity rope is still required?

    Rope takes up space and has limitations, like weight, limited tensile strength, frictional wear, oscillation, and bulk; OK, there are some energy savings with a counter weight system, however it probably causes problems too.

    I wonder if a less indirect drive approach could be used to move the lift car e.g. something like a worm drive, chain loops, belt loops. etc.

    Silverburn

    Rockets would be expensive and dangerous, so not a smart idea! A maglev and a rail gun work on different principles; a maglev is non-contact with magnetic suspension and a linear motor, a rail gun uses a large capacitor bank to suddenly release a massive pulse of current to flow through the bars and a conductive projectile, to generate an intense repulsive magnetic field, and can cause serious destructive erosion of the bar and projectile, as well as massive and probably lethal acceleration! I suspect linear motors are not used because even without the weight of a cable to supoort, they probably use a lot more power than a normal lift motor.

    Asf,

    As for space elevators, this was a fantasy of Aurthur C., Clarke's; I doubt it will ever be physically possible to make a strong and long enough vertical structure, let-alone a usable space anchor. It may be feasible to make a transport tube inside or outside Mount Everest to lift space vehicles to be launched from the top, then have them glide back down from space. We will probably continue to need chemical energy rockets for use in planetary atmospheres, and have to use Nuclear powered propulsion, for sane transport times to and from the nearest possibly survivable planetary orbit. The only other alternatives I can currently think are, we somehow discover or create some useable kind of anti-gravity or wormhole through space.

  27. a_mu
    Facepalm

    ropes do seem a little old hat

    Railways were ropes with static engines,

    but they moved to engines on the cars a long time ago.

    does seem like its time to move to a vertical rail based system,

    with all the safety interlocks naturally,

    and as said above, it does mean the lift cage does not need to only go up / down, they can switch tracks with points, and can go horizontal as well as vertical,

    just needs some one to do it,

    wonder if its already patented ?

  28. MatsSvensson

    No thanks, that sounds dangerous!

    Ill take the stairs.

    See you next month..

  29. Adam Foxton
    Pint

    How about buoyant elevators?

    It is well within our powers to make a pipe that'll survive the 1500psi or so that a water-filled body would have exerted on it's lower end if it was a kilometer long. So build a very large diameter pipe and flood it. Fill a buoyancy tank at the bottom end to rise and vent it to descend.

    You now have an elevator system that can, for the energy price of a small ground-mounted air pump and something to pour rainwater into the shaft to replace any small losses, lift massive weights thanks to the buoyancy of air in water. It also becomes simple enough to route multiple cars around one another and if a car fails it won't drop people to their doom, though you'd want a lower end of the shaft that would correctly orient the car to have it mate with an emergency exit.

    Breathing could pose a problem unless you had tanked-in oxygen and/or fill-up points. Or had it rise fast enough that you didn't need to worry about it and could pump in more fresh air whenever you docked with a floor.

    This isn't like SCUBA or SAT diving; each car would be a pressure chamber so you'd have no problems with regards to the Bends as there'd be no pressure change acting on the passengers.

    1. GreanLawn
      Pint

      Re: How about buoyant elevators?

      I like the idea - if there was a big rubber seal around each door on the inside of the lift shaft, and on the opposite wall, a hydrolic ram to push the elevator car against the seal. Then the space between the two doors is drained away before the doors open. The cars could be only very slightly denser than water, so it weights only the weight of the passengers. And a polyester rope which is neutrally buoyant would mean the rope does not have to support its own weight, only that of the passangers. There would need to be space around the car for water to flow from above to below it.

      I'll make one tonight out of lego, and take it on Dragons Den

    2. Charles 9

      Re: How about buoyant elevators?

      Have these pipes you mentioned possible been build over a kilometer long and at diameters over 2 meters? Furthermore, the pressures of a vertical pipe are very uneven (concentrating at the bottom). Then there's the matter of opernings? How watertight can you make the seals between the pipe, car, and door, so that you don't have a massive failure when the doors open on the ground floor? The ground floor opening has to be able to hold back the weight of the ENTIRE column of water—repeatedly, reliably, rapidly, and non-permanently.

      1. Adam Foxton
        Happy

        Re: How about buoyant elevators?

        Pipes of man-carrying diameters carry oil and gas across continent-spanning lengths and at pressures an order of magnitude higher than those you'd see in a 1km water column (which would top out at about 1500psi). This would be a larger pipe, but pipe can be made at any diameter you want.

        With a 2mx2m-face elevator, on the ground floor you'd have about 42MegaNewtons total force pressing the lift against whatever seal you chose, and with that sort of pressure you could just use a metal-to-metal seal rather than an easily-damaged rubber one. You'd actually have to design it to NOT seal as well as possible!

        Also, modern skyscrapers get rid of some of the problems of air-columns by using revolving doors (essentially they're permanently sealed). A similar arrangement could be used to keep a few per-floor segments decoupled. So you've got a number of 2-floor or 10-floor sections of pressure to worry about rather than a whole 1km long water column.

        You'd have a minimum of 3 doors, 1 on the car and 2 on the building. The car would dock with the wall of the lift shaft and the first building door would open, venting the excess water and either pumping it back up to the roof or just venting it to the drains. The doors of the building and car with people behind them would then open, allowing (dis)embarkation. The people-protecting doors close, the building's "inner" door closes, and the space between the car and building inner doors would then be flooded with water, removing the sealing pressure and releasing the car.

        I wouldn't bother with any ropes- they'll get wrapped up together. Buoyancy control will provide an appropriate way to control up/down motion with electric thrusters or something else providing lateral movement to get it close to the door (using the idea of one or two transit shafts with the doors arranged between them to allow for some quite efficient routing of multiple cars).

        This also provides the added benefit of being incredibly safe in a fire- you're in a water-filled tank that would take a near-impossible amount of heat to heat by more than a few degrees and it can vent the lifting fluid to calm any fires. If it fails you could drain it and recover anyone trapped inside.

        Maintenance would be simple with underwater ROVs and AUVs. Divers couldn't stand 1km pressures.

        You could wrap it around buildings- say, a double-helix of lift transit shafts with cross-members where the lifts can change passengers. It could even be designed so that in the event of a fire the shafts could be drained, the pumps turned to minimum and you've got a kilometer-long waterslide to the ground floor.

        Install a few radiator platforms going down the side and you could keep the water very cool, saving a lot of money on air conditioning.

        With a lack of lifting rope (and some underslung buoyancy), you'd be able to have it buoy up to the roof without unsightly roof constructions.

        And just THINK how extravagant a water-filled tower would look in the desert of Dubai. The tallest tower, FILLED with the rarest resource.

        I'm just off to design this thing. There's got to be some rich git out there who wants the tallest tower with the biggest, baddest-ass lift.

        1. John 62

          Re: How about buoyant elevators?

          Dubai is beside the sea, so water isn't all that rare there. They desalinate vast amounts of sea water for drinking and irrigation. The city is really quite lush already.

    3. Anonymous Coward
      Anonymous Coward

      Re: How about buoyant elevators?

      A lift system in London uses water to power a hydraulic ram. IIRC they use the tidal height change in the River Thames to refill the reservoirs twice a day.

  30. Anonymous Coward
    Anonymous Coward

    "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.""

    And this is why we're doomed. The fact that the challenge of building bigger buildings is seen as the problem, rather than the number of people who want to live in them.

  31. Passing Through
    Megaphone

    Bad idea

    A high percentage of advanced projects end in disaster: Titanic, Concorde, Space shuttle x2, Hindenburg and numerous other airships, Twin Towers, various fancy bridges, very nearly Apollo 13, Comet, Bluebird, breast implants, etc etc.

    Very often we get all impressed by how clever we are and then it all goes horribly wrong

    Extreme high rise buildings are unnecessary, quite apart from being a pain to use, when the lift conks out, as it will, how many floors of stairs do you want to have to climb? its ok as a novelty now and then if you are fit, but for anyone not so able or anyone in an evacuation situation, not good.

    Give me a few floors at most and I'm happy.

    Longer cables might be useful in mines.

    1. Charles 9

      Re: Bad idea

      Funny, the Olympic had in industrious career, four of the six space shuttles are now museum pieces, many other zeppelins kept going and we never had a problem with helium airships, 9/11 was a deliberate act (something no engineer can ever fully account), Apollo 13 got back to Earth safely and the project still got us to the moon around 6 times: several times WITH BAGGAGE. Sure, there have been missteps along the way, but that's why the adage: "No guts, no glory." Diving into the unknown has its risks, but man the rewards can be sweet. Unless you saying it was wrong for us to discover fire and leave the caves.

      As for buildings, consider how much people flock to cities. They want to congregate. How do you achieve that on limited land space (that's why Manhattan is a poster child for this—they hit the problem early because they're on an ISLAND). The alternative is sprawl like Los Angeles with all the problems that come with a sprawl. Going up allows for denser cities which means lower travel times and less frustration and so on. And just how often do ALL the elevators in a skyscraper fail, except in a disaster (and in a disaster, location doesn't really matter much)?

      1. Alan Brown Silver badge

        Re: Bad idea

        "9/11 was a deliberate act"

        From an engineering point of view it was a magnificent sucess which validated that the original design performed above and beyond its design spec.

        The towers were designed to collapse internally if stuck by a fully fuelled aircraft (707-size at the time of design and there were precedents for skyscrapers being hit by aircraft in NYC), rather than toppling.

        That they both managed to stay standing _at all_ after the impact was a design triumph. Withstanding the intensity of fire that they did for the period they did was another design triumph no matter what anyone says about spray on concrete coming off the girders - in a normal fire that wouldn't have happened and it was expected the buildings would collapse near-immediately in a substantial impact.

        My only criticism of the WTC (and most skyscrapers) is their lack of integral firefighting facilities such as sprinklers and substantial roof-level/service floor water-tankage.. Very few jurisdictions require them despite most firefighting systems being unable to go higher than about 20 floors (sprinklers would NOT have helped in 9/11)

        1. Charles 9

          Re: Bad idea

          "My only criticism of the WTC (and most skyscrapers) is their lack of integral firefighting facilities such as sprinklers and substantial roof-level/service floor water-tankage.. Very few jurisdictions require them despite most firefighting systems being unable to go higher than about 20 floors (sprinklers would NOT have helped in 9/11)"

          I think the main problem with that is that the WTC towers aren't on a whole very stiff; they were designed to sway in the breeze. Now, water is on the whole a decently dense substance. Dense enough that water tanker trucks need to be careful as they drive as the water's inertia can impart surprise forces on the truck: especially if it sloshes around inside, moving from side to side. So imagine a tank of the stuff the size of a swimming pool being stored about 1,000 feet up a rather flexible structure. I imagine that's going to make it somewhat top-heavy: not a good thing from an engineering viewpoint.

          As for being designed to take an aircraft impact, did that include a direct but oblique (thinking angled downward) impact directly on one of the corners (which were load-bearing IIRC)?

    2. Anonymous Coward
      Anonymous Coward

      Re: Bad idea

      "A high percentage of advanced projects end in disaster: "

      More people were killed by trams than by the transport examples you cite. It is highly likely that wooden-wheeled ox-carts killed people by mowing them down or breaking a wheel. Road deaths have decreased as vehicles have become more hi-tech.

      Life has risks. Even if you dodge all the curve balls - there's always an end stop.

  32. Anonymous Coward
    Anonymous Coward

    Elastic

    How much does that long cable stretch under a full load?

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