Chinese Firm Approved To Raise World's Tallest Building In 90 Days 307
kkleiner writes "The long anticipated Chinese construction project called Sky City, a 220-story building that can house 30,000 people, has finally received approval from the central government to break ground. The firm Broad Sustainable Building previously constructed a prefab 30-story building in 15 days, but for Sky City, they have an even more aggressive schedule: 90 days to build 2,750 feet into the air. Once completed, the building will be a place for people to both live and work, with recreational facilities, theaters, a school, and a hospital all within the structure."
Re:Larry Niven's Oath of Fealty (Score:5, Informative)
"Arcology" is the term of reference...
Old news, obsoleted six months ago (Score:5, Informative)
Re:Units in the summary (Score:2, Informative)
Learn to guesstimate big numbers. It will help reduce your apparent anxiety when confronted with American imperial units of measurement.
It takes about a second or so of guesswork - 1000 feet is about 300 meters. 2000 is 600. 75% of 300 is 225, so we get a guesstimate of 225 + 300 + 300 = 825m . In reality, we're off by about 13, but remember, that doesn't matter. If you're really good at math, you could subsitute 304 for 300 and get closer to the reality, but why bother? The more you do conversions like that, the easier they get.
Out of politeness to your future self, you should adjust your attitude and simply accept that sometimes you'll have to think a little bit. Not much, fortunately, but a little.
And if you absolutely can't handle it, then take responsibility for your own information consumption and install an automatic converter. There are plugins for firefox and chrome that automatically convert units to and from metric and imperial. You can even auto-convert units of currency. You'll never have to waste another second on translating again.
Real politeness never imposes on others. Do unto others as you would have done unto you has a nice corollary: do for yourself what you'd expect to do for others. At some point you have to take care of yourself. :)
Re: 90 days to raise... (Score:4, Informative)
The building itself is well built from what i can see, but you can't prefab a foundation, and a real foundation takes time.
IANASE (I am not a structural engineer) but there is serious concern about prefab for something this height. FTA:
Head of Structures for WSP Middle East, Bart Leclercq ... likes the idea of prefabrication but says concrete poured onsite in tall buildings provides stiffness, and the time it takes concrete to cure is non-negotiable. He thinks the five-year mark set by the Burj Khalifa is about as good as it gets with current techniques and technologies.
I'd be very interested to hear from anyone here who has expertise in concrete.
Re: 90 days to raise... (Score:5, Informative)
IAAASE (I actually AM a structural engineer) and I am definitely concerned. Concrete will have to be poured on site, since there will need to be a homogenous shear force resistance from the top of this thing all the way down to the bottom. If the sections were simply bolted together, then 200+ vertical slip-critical connections is going to give you a heck of a wobble.
Poured reinforced concrete is a composite connection, the steel acting to counter the moment effects and tension forces in concrete.
However, I have not seen all of the plans for this thing, and if they were to assemble, say, 20 storeys with formworks for shear assemblies, then poured a twenty story concrete lift on site, waited three days to achieve 75% curing strength, then kept going with 20 more storeys, this could work. It's not impossible, but there's a lot of problems that, while SOLVABLE, would never get approval in North America due to unacceptable levels of risk.