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Other Stuff => Other Topics => Topic started by: tubesornothing on December 11, 2009, 11:56:56 am

Title: Way OT - fall down and go boom
Post by: tubesornothing on December 11, 2009, 11:56:56 am
Check this out:  http://www.zonaeuropa.com/200906c.brief.htm#012

scroll down to number 12.

Title: Re: Way OT - fall down and go boom
Post by: FYL on December 11, 2009, 01:18:10 pm
Building not collapsed just a test. Excellent Chinese quality. All ploducts ale tested befole shipping. How many amps you want sil ?

Title: Re: Way OT - fall down and go boom
Post by: tubesornothing on December 11, 2009, 02:17:07 pm
HAH - you  slay me, man!
Title: Re: Way OT - fall down and go boom
Post by: RicharD on December 11, 2009, 07:04:29 pm
What's missing from this picture?

(http://www.zonaeuropa.com/20090627_19.jpg)

It's called rebar.  Concrete ain't nothing but heavy w/o steel reinforcement.  It's a good thang it fell before the place was full of people.

Title: Re: Way OT - fall down and go boom
Post by: bnwitt on December 11, 2009, 10:02:42 pm
  It's a good thang it fell before the place was full of people.

Not according to the Chinese population control czar.
Title: Re: Way OT - fall down and go boom
Post by: Shrapnel on December 12, 2009, 02:38:21 am
I presume no good retainer wall for the garage area was in place either, that didn't help how close it was without one. (I don't remember seeing a wall in the images.)
Title: Re: Way OT - fall down and go boom
Post by: Geezer on December 12, 2009, 03:36:05 am
Quote
Nine people linked to the building collapse, including the real estate developer, contractor and the supervisor for the project, have been put "under appropriate control", said the official Xinhua News Agency Sunday evening.

The story sez that "1 worker died".......I suspect that a total of 10 people died (or at least will never be seen again), if you get my drift.  :sad:
Title: Re: Way OT - fall down and go boom
Post by: bnwitt on December 12, 2009, 09:34:19 am
That is one of the worst examples of steel placement I've seen in Caisson construction.  What rebar there is is too close to the outside surface of the columns.  It should be at least 3 inches deep into the column.  I don't understand the hollow columns for a building of that size either.  There must be a concrete shortage in China.  The whole purpose of caisson construction is to support the building in poor soil areas by placing the footings on bedrock.  As described in this little blurb a caisson's steel content is determined by the conditions of the surrounding soil and axial load requirements

"It is basically a circular column with a high moment and a low axial load.  The point of maximum moment will be below the ground line by several feet depending on the type of soil.  The amount of steel required will be a function of the maximum moment, the concrete strength, and the diameter of the foundation."  I wouldn't go near any of the other buildings in that project.  Especially if it was raining.
Title: Re: Way OT - fall down and go boom
Post by: tubesornothing on December 12, 2009, 10:16:31 am
For all you budding civil engineers out there: http://www.eng-tips.com/viewthread.cfm?qid=248426&page=9
Title: Re: Way OT - fall down and go boom
Post by: DummyLoad on December 12, 2009, 10:19:59 am
another fine example of chinese engineering...  :rolleyes:
Title: Re: Way OT - fall down and go boom
Post by: RicharD on December 12, 2009, 02:33:00 pm
I've looked at these pictures several times and there are 3 thangs that baffle me about those piers.

1.  As mentioned before, there's mesh embedded in the concrete instead of rebar.
2.  The piers are hollow.
3.  The diameter appears to be only about 12".

I've poured piers for parking lot pole lights before.  They always use rebar cages, not mesh.  The diameter is always 24".  I've never seen a hollow pier.  I'm talking about 25' pole lights, not a 12 story building.

Title: Re: Way OT - fall down and go boom
Post by: tubesornothing on December 12, 2009, 02:45:36 pm
On the eng-tips thread I posted above, they guys posted the actual engineering drawings for the columns.  They are "suppose" to be pre-stressed hollow pilings with steel re-enforcement.  The conclusion on the eng-tips forum is that they cheaped out on the re-enforcing steel.  Add to that the side loads caused by a load of wet dirt, then undermining the foundation, PLUS a break in the river.  Fall down go boom.

Title: Re: Way OT - fall down and go boom
Post by: bnwitt on December 12, 2009, 06:46:29 pm
For all you budding civil engineers out there

Uh, dat be structural big doggy. :grin:
Title: Re: Way OT - fall down and go boom
Post by: tubesornothing on December 12, 2009, 07:05:52 pm
For all you budding civil engineers out there

Uh, dat be structural big doggy. :grin:

Not quite: http://en.wikipedia.org/wiki/Civil_engineering

Civil engineering is the overarching discipline that is broken down into sub-disciplines such as structural, materials, surveying, geotechnical. etc.  Not just roads and bridges as commonly mistaken.  Saying "civil engineering" is an easier way than saying both "structural" and "geotechnical" in which this case encompasses both.
Title: Re: Way OT - fall down and go boom
Post by: bnwitt on December 13, 2009, 08:40:36 am
Well I guess we'll agree to disagree then:

Structural engineering is a field of engineering dealing with the analysis and design of structures that support or resist loads. Structural engineering is usually considered a specialty within civil engineering, but it can also be studied in its own right.

http://en.wikipedia.org/wiki/Structural_engineering

You could also just say "engineering" and cover everything I guess but we've come along way in each engineering discipline in the last couple hundred years and the disciplines are very stove piped now.  You can find structural engineering as a graduate major in schools all day long and this is typically the graduate degree held by all of the structural engineers who review and stamp my drawings.  A civil engineering bachelors degree is just the general into the structural world.  To hold a P.E. in Structural Engineering requires a Masters degree in Structural Engineering along with a Bachelors degree in Civil Engineering.  At least most states:

http://www.uscollegesearch.org/structural-engineering-colleges.html

I wouldn't let just any MD do my heart surgery.  I'd want a heart surgeon M.D.

However, all of that being said, it probably was a guy with just a civil engineering degree who designed that building. :laugh:
Title: Re: Way OT - fall down and go boom
Post by: tubeswell on December 13, 2009, 12:36:18 pm
Those foundations are a joke for buildings of that height. A strong wind could blow it over.

And the soil looks like manure.

So anyone wanna invest in some nice Shanghai apartment towers?
Title: Re: Way OT - fall down and go boom
Post by: FYL on December 13, 2009, 12:49:00 pm
Quote
So anyone wanna invest in some nice Shanghai apartment towers?


Would you consider a trade for some prime Dubai artificial islands?