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View Full Version : The Power of Prefabrication-30 Storey Chinese Hotel Built in 15 Days (video)


Feuer Frei!
02-18-13, 11:22 PM
Pretty cool to watch:

https://www.youtube.com/embed/GVUsIlwWWM8?rel=0

AVGWarhawk
02-19-13, 08:53 AM
Amazing. I like that they had a smaller crane that used the structure for support and lifting. Also the standard larger crane we normally see.

Jimbuna
02-19-13, 09:00 AM
House of cards :o

AVGWarhawk
02-19-13, 09:06 AM
House of cards :o

I do't believe so. The building looks to be a huge erector set. All pieces made and bolted together on site. Plus, note the pilings drilled into the ground and ram used to sink them. The structure looks quite solid.

Jimbuna
02-19-13, 09:43 AM
I do't believe so. The building looks to be a huge erector set. All pieces made and bolted together on site. Plus, note the pilings drilled into the ground and ram used to sink them. The structure looks quite solid.

Let me know for sure after you've stayed there and given it a good test :)

Herr-Berbunch
02-19-13, 09:43 AM
:hmmm: Timer stopped at 360:00 with still work to go. Nevertheless it's still mighty impressive. There is a lot to be said for prefab stuff, and not like from from the sixties and seventies. I know that if I win the lottery I'd have a Huf Haus to my spec. :D

AVGWarhawk
02-19-13, 10:41 AM
:hmmm: Timer stopped at 360:00 with still work to go. Nevertheless it's still mighty impressive. There is a lot to be said for prefab stuff, and not like from from the sixties and seventies. I know that if I win the lottery I'd have a Huf Haus to my spec. :D

Our new home was completed in 3 1/2 months. The frame was created off site and trucked in on a flat bed. After the foundation was poured and cured, framing took under a week. Cutting pieces on site and nailing together would have taken quite sometime.

AVGWarhawk
02-19-13, 10:41 AM
Let me know for sure after you've stayed there and given it a good test :)

Sure will. I would try it just so I can do some traveling. :D

Ducimus
02-19-13, 02:12 PM
I do't believe so. The building looks to be a huge erector set. All pieces made and bolted together on site.

It is. In USAF engineer parlance, we'd call it a PEB, or Pre Engineered Building. It is one big lego or erector set. Construction phases are generally
- Ground/grade preparation
- Foundation work. (Footers, columns, stemwalls, pad, etc etc)
- "swinging steel". (what you saw during most of that video)
- the rest is just internal work. Electrical, HVAC, carpentry, etc.


Plus, note the pilings drilled into the ground and ram used to sink them. The structure looks quite solid.

Yeah, it looks great going up, but that video isn't going to show things you can't see. All i can say is, I hope that in this regard, craftsmanship in China is better then what I saw in Korea. Off the top of my head, this building has 3 possible ways to fail.

1.) Crappy grade and/or foundation work. (ranging from really wet and runny concrete, to poor soil compression, or the soil composition itself)
2.) Defective structural design somewhere.
3.) Defective steel used in Beams, trusses, bolts, etc.

If any of these do occur, they won't show up right away. May take 5, 10, even 20 years or longer for the problem to manifest itself, depending on how bad it is.

AVGWarhawk
02-19-13, 02:23 PM
Bad concrete mix I have read about before and has plagued quite a few structures. Specifically when the concrete guy cuts corners.

Ducimus
02-19-13, 07:33 PM
Bad concrete mix I have read about before and has plagued quite a few structures. Specifically when the concrete guy cuts corners.


Well, concrete consists of two things. Cement and aggregate (small rocks). The cement particles binds with the aggregate though hydration. Water is a funny thing, because while its needed for the hydration process to occur, to much of it will spread the cement particles (the binding agent in concrete) farther apart. So in effect, the more water you add, the farther apart the binding particles are, hence the weaker the concrete becomes.

Now, the water level of concrete is tested in what's called a "Slump test". (http://en.wikipedia.org/wiki/Concrete_slump_test). In the United States (or by US standards), the ideal slump for concrete is 3 inch's. Less then that, and it's too dry, more then that and its too wet.

So here a couple wildcards.
3 inch slump, while ideal, is harder to work with then say a 4" slump or greater. IF your being lazy, or you have a project manager worried about deadlines, you water the 'crete down so its easier to work with.

OR,

if your working with pumper trucks. (http://en.wikipedia.org/wiki/Concrete_pump), you may have to water the concrete down to get it through the pumps.

I don't know about China, but I do know about Korea. The koreans ran EVERYTHING through a pumper truck. Often we contracted needed concrete from local contractors, and the crete we got delivered off their transit trucks had a slump averaging between 7 to 9, and we had some batch's even wetter. It was just absolute slop. This is one reason why their bridges and malls fall down. (both of which occured while i was stationed there, saw it on the local news in a korean bar I used to frequent in Suwon)

AVGWarhawk
02-19-13, 07:38 PM
I was watching a program a few weeks back. It concerned structural failure. The buildings that collapsed had samples of concrete cut from the structure. They analysed the concrete noting the aggregate was to large thus producing failure. It was quite interesting.

Ducimus
02-19-13, 07:43 PM
I was watching a program a few weeks back. It concerned structural failure. The buildings that collapsed had samples of concrete cut from the structure. They analysed the concrete noting the aggregate was to large thus producing failure. It was quite interesting.

Yeah your right about size of aggregate. I hadn't thought about that. We always used certain sized aggregate for concrete, it never occured to me to use anything larger then what I'm used to seeing. But your 100% correct, oversized aggregate, is tantamount to throwing in large rocks as filler (yes i've seen that done), which as strength is concerned, doesn't work.