Saw part of a Discovery show about the worlds tallest building in Dubai. The show ended when they were around 85 floors, and that’s half way.
Anyway, they talked about the steps taken to keep the building plumb as it goes up, and they saisd that at the 85th floor it is only out of plumb by 3″. Seems like a lot to me.
“When asked if you can do something, tell’em “Why certainly I can”, then get busy and find a way to do it.” T. Roosevelt
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Take a drive over to Pisa.
A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Yeah, and the contractor said to the owner:
Does this mean I don't get paid?
1/8" every 35 feet sounds pretty good to me (assuming 10 foot stories). Better than I usually do.
zak
"When we build, let us think that we build forever. Let it not be for present delight nor for present use alone." --John Ruskin
"so it goes"
Apparently when they built the CN Tower in Toronto they compensated for the torque exerted by the earths rotation on the setting concrete. The exec. PM for the Burj tower in Dubai is joining my project next month. Also we are working on another tower going up in Asia that will be even taller when completed. The skyscraper race is back in full steam.
I went to start a 3 story condo project 2 years ago, set up my laser to establish an exterior wall and the steel was out 4". The iron workers racked and cut to get it to 2".
That set the stage for a miserable project for all. I think that place was built on an Indian burial ground or something.
I have only worked outside up to 18 stories. I honestly don't think I could or would do 85.
One thing for sure, I would hate to have to wind up that plumb bob string. ; ^ )
Mike
Trust in God, but row away from the rocks.
It was windy the day they put it up.
let's see here, assuming 10 ft stories 85 x 10 = 850 ft x 12 inches/ft = 10,200 inches tall.
3 inches (error) / 10,200 = .000294 x 100% = .0294%
so, this building is only .0294% off or to put it another way, they are 99.97% accurate.
By comparison if you frame an 8 ft wall 1/16 inch out of plumb you are
you are .065% off. Still very accurate but over twice as much off as the building. And that accuracy is repeated over 85 times, once per story.
1" out of plumb for a house would be considered ok, but that's as high as it goes. And there isn't an entire crew dedicated to measuring the plumbness. I think my point was relative to the cost of construction and the height involved. When they got to 1" out of plumb, why didn't they start taking corrective action to go the other way?
Very early in my career I was a project engineer for the gc on a 49 floor building. Talk about pucker factor. And close tolerances all around. The architect was I M Pei's office in NY, and I think Philip Johnson waas the guy for our building. There were no cut tiles in the restroom ... we had to adjust the framing and sheetrock so that all the tiles were full size. They were 2" I think, but still it took some good layout.
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
SOOOO>>>>
when they get to the top...
the top floor will "cantilever" out over the base by 6"
unless they goe 3" back the other way...
Also...
If they can measure how far off they are,m how come they can keep it plumb as they are building??
Is 3'' a gradual .0249% over each story or do they go 1/2" this way and back 3/4" and back 1/2".....
does Stabila make a 3000' expanding plate level???
Maybe they need a festool setup!!!Welcome to Breaktime
Home of
The Aristocrats
i'd like to think each floor is a little off: 1/2" one way, 3/4" back the other way, etc. it's the dr. seuss school of architecture.
I'd like to think that too...
did the article say, or does anyone know, what the tolerances for skyscrapers are???
Inquiring minds...Welcome to Breaktime
Home of
The Aristocrats
I don't know about anyone else, but my tolerance is very low.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
plumb.. that's the deep rich purple tasty thing when it's ripe..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
Unless it is of the Green Gage variety .. then it is a yellowish to green color. Tastes great when ripe though .. very sweet.
Is that on a calm day or when the wind is blowing?
:)
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Saw that show too.
They were using GPS to keep it plumb....
How long before Dewalt or Stanley come out with one of those??
Mclaren
when I was in high school, trigonometry class studied the St Louis arch - at 630 feet high, it's not tall by some standards, but the shape made for the challenge - and you can imagine the pressure/tension (of the human type) surrounding the fit of the keystone -
if I remember right it was a couple of tenths of an inch off - they had the fire department hose down the lower part of one leg to achieve the 'perfect' fit - the contraction of the material from cooling being enough to bring things into alignment -
"...they had the fire department hose down the lower part of one leg..."
My understanding of what happened was that the sun heated the metal on the south leg. The fire departmetn hosed it down to cool off the surface of that leg and get things back in line.
(I've sat through the movie in the base of the arch about 4 times)
To get anywhere, or even live a long time, a man has to guess, and guess right, over and over again, without enough data for a logical answer. [Robert Heinlein]
> (I've sat through the movie in the base of the arch about 4 times)Twice is just stupid, but four times is out-and-out self-abuse.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
When we have out of state guests, they often want to see the arch. So when I've taken people there over the past ~20 years I often end up sitting through it.
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. [Einstein]
Once was plenty for me. I suppose it's not as bad when the crowds aren't too bad, though.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
So how many times have you been to the top? I don't think I could be in a space that small for more than 5 seconds.
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
You can sorta stand up at the top. It's the trip up that's kinda scary. The trolley system they use doesn't seem too robust, and there's no obvious way to evacuate the thing should it get stuck. But worst of all is standing in line (packed elbow to elbow) for about 90 minutes, getting shuttled from room to room to make you think you're "almost there" when in fact it's gonna be another 30 minutes.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Edited 2/1/2007 6:32 pm by DanH
It amazes me what mid-westerners do for entertainment ;-)
Come on now TGNY, you're blowing their enthusiasm all out of proportion. ;)
I don't think there is any chance of that. I see throngs of them daily lined up in NY for one thing or another.
Last time I was in TO I felt like a total 'country mouse' as I walked out of Union Station into full-on downtown bustle. Quite a change from my four stoplight town.
To get back to the thread, those downtown bldgs seemed totally out of plumb...they were all leaning toward a tiny patch of sky. ;)
Edited 2/2/2007 3:29 pm ET by Pierre1
IIRC, at Disneyland/world the buildings lean back slightly, to make them seem taller. They also reduce the height of each successive floor (as seen from the outside), so the 3-story building is only a scant 2.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
how many times have you been to the top?
I've been there twice - once before kids, once with them -
the space is pleasant, and we had no nervous issues - the ride up takes a while and they assure you that there are stairs for emergency use - I heard the trolleys got renovated a couple of years ago -
we walked around it in december, but didn't go in - it is a great structure - kudos to whoever came up with the idea, and the same to whoever scratched up with the $ to make it reality - I think it cost maybe $16 M? - - don't know what that is in today's dollars, but it sounds like a bargain to me -
"there's enough for everyone"
"So how many times have you been to the top? I don't think I could be in a space that small for more than 5 seconds."
I've been up maybe 6 times over my lifetime.
The space at the top is bigger than you'd think. You can stand up easily in it. My only complaint is that the windwos are a bit small.
Man should forget his anger before he lies down to sleep. [Gandhi]
Is that from claustrophobia or acrophobia? If it is acrophobia, you probably don't want to peer over the edge of the observation deck at the Space Needle in Seattle or walk out on the glass sky walk that is being built over the Grand Canyon. Actually, what has gotten to me as much as anything is the glass elevator at the Hyatt Regency in San Francisco. OK, maybe worse was walking across an expanded metal catwalk about five stories up when I was inspecting some industrial buildings.
reminds me of the donkey in the shrek movie, "lets do that again!"
yer goin the right way fer a smacked bottom!
what is plumb? It's what's perpendicular to level.
The code will allow them close to 12" at that point, so 3" doesn't sound too bad. What I want to know is how they determine this figure since any small breeze is pushing that building around by at least that much at any given moment.
As someone noted, they were using gps, and they showed some kind of inclinometer attached to the building every 5 floors. I think the 3" is a mean number, like sea level.
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
There are some jokes here about wind, but have you ever seen mechanisms in tall building to combat sway. One example I saw was a large (school bus sized) weight on rollers that rolled as the building swayed. The sway was measured in feet and not inches.
"Hey, can you see that guy on the sidewalk way down there? No wait, now I can't see him. Oh there he is., no can't see him ..yes.....no there he is...nope, you looked too late."
Edited 2/2/2007 5:18 pm ET by txlandlord
Edited 2/2/2007 5:19 pm ET by txlandlord
Yeah, they vary, but all tall buildings (I suppose over 50 floors or so) have to have something. In some cases it's a massive weight, suspended like a pendulum, designed to resonate at a frequency that will cancel the building's natural sway frequency. In other cases a weight that's moved about by hydraulic cylinders is used.And it gets even more interesting for earthquakes. They have to compensate for ground motion to keep the building "upright". Hydraulic accumulators are often needed to assure power will be available during a quake.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Thats more than I know, but I did know that I'd seen some amazing stuff on Mega Structures or similar shows.
Oddly, IEEE Spectrum covers this kind of thing a lot (relatively speaking). There have been several articles on the subject over the past dozen years.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Being in a skyscraper in a strong earthquake will allow you realize just how much the top floors do sway. It is almost enough to give you whiplash, among other things...
Being in a skyscraper in a strong earthquake will allow you realize just how much the top floors do sway. It is almost enough to give you whiplash, among other things...
Been there, done that. We had flown into Vegas for a house-hunting trip in 1994 and at 4am I was 1/2 awake on the 18th floor of the Riviera hotel when the door on the little safe in the room started clanging back and forth. I soon realized that it wasn't just the safe door that was moving, and called down to the front desk to see what was going on. "Oh, they're having an earthquake in Los Angeles" the girl said non-chalantly. That was a little thing some of you may remember called the Northridge Earthquake, felt 250 miles away. When we spoke to people that morning at breakfast, they hadn't felt anything because they were on the lower floors.
Bob
A young prune.