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Old January 2nd, 2016, 07:43 PM   #1
Quantumstate
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Dubai Burnings - Any Structural Engineers Present?

I was astonished with the speed of the fire at the Address Downtown. It looked to me as if it was the carpet that was burning, not so much the façade.

But this, the burning of the Torch also this year (BBQ grille on a balcony), and the Tamweel Tower fire in 2012 (cigarette), got me wondering. With the obviously inferior building codes in Dubai, why didn't any of these buildings pancake like the three WTC towers? What can the explanation possibly be for the utter collapse of 7WTC, not to mention the others? This should never happen and buildings are designed so this never happens, at least in the US. And yet Dubai buildings don't collapse, time after time?
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Old January 2nd, 2016, 08:23 PM   #2
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These are concrete structures, with lower burn temps, and lacking the damage of a jet airliner crashing into them.

There is likely structural damage, but not as extreme.

I wouldn't stay in any of them though.
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Old January 2nd, 2016, 09:39 PM   #3
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The building codes were changed but all of these fires are on buildings built when the codes were still "inferior"
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Old January 2nd, 2016, 10:30 PM   #4
Salseando
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WTC

The WTC incident was an inside job , a detonation of the towers...more information in lots of videos in YouTube
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Old January 2nd, 2016, 10:53 PM   #5
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Quote:
Originally Posted by Salseando View Post
The WTC incident was an inside job , a detonation of the towers...more information in lots of videos in YouTube
Is this the uae tactic, distract from their tower disasters with wtc bullshit?
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Old January 2nd, 2016, 11:00 PM   #6
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Quote:
Originally Posted by Salseando View Post
The WTC incident was an inside job , a detonation of the towers...more information in lots of videos in YouTube
This thread is about Dubai, not NYC
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Old January 3rd, 2016, 08:37 AM   #7
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This thread is about the WTC buildings and Dubai. Let's not get political like mentioning that records for 3,000 SEC investigations were destroyed.

I'm hoping we have some technical people here who are able to comment on why the disparity in results, with some solid information. Why were our superior buildings, inferior? Why did 7WTC drop exactly like an implosion? And why did Dubai's, uhm not.

Last edited by Quantumstate; January 3rd, 2016 at 08:44 AM.
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Old January 3rd, 2016, 04:54 PM   #8
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Quote:
Originally Posted by Quantumstate View Post
This thread is about the WTC buildings and Dubai. Let's not get political like mentioning that records for 3,000 SEC investigations were destroyed.

I'm hoping we have some technical people here who are able to comment on why the disparity in results, with some solid information. Why were our superior buildings, inferior? Why did 7WTC drop exactly like an implosion? And why did Dubai's, uhm not.
Then change the title.

What is your purpose here?

What is your agenda?
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Old January 4th, 2016, 06:55 AM   #9
Quantumstate
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A. The title is precise.
B. I do not have an 'agenda'.
C. My reason for these questions is not clear to you? I don't know how to ask this any clearer. English is my native language. Maybe you should tell me what you do not understand, if you are qualified to respond to my questions. If there are no technical people here, I will understand.
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Old January 4th, 2016, 10:50 PM   #10
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You "questions" have been answered.
You don't like the answers.
You have an agenda.
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Old January 5th, 2016, 10:45 PM   #11
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One was a steel building.

One was a reinforced concrete building thats why.

They react differently to heat.
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Old January 7th, 2016, 12:36 AM   #12
Eric Offereins
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True. Steel weakens considerably at 600°C or more, reducing the load bearing capacity.
The WTC was a concentrated fuel fire , weakening the steel at only a few floors. The weight of the buidling above did the rest.
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Old January 7th, 2016, 09:25 PM   #13
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Steel has a nearly instantaneous failure mode. Concrete not so much.

The weight of the building and gravity. I make a lot of money off of gravity. It's free.
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Old January 9th, 2016, 08:20 PM   #14
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There are so many differences, both in the buildings and the fire, that make then almost uncomparable.

1) As mentioned, WTC buildings had a steel structure, those Dubai's buildings, as I understand, are concrete. That's a huge difference because concrete is much more resistant to fire than steel.

2) Modern office buildings as WTC, are open plan, meaning that any fire can spread easily. Dubai's buildings are hotel or apartments, meaning they are more compartmentalized, so a fire doesn't spread as easily.

3) Twin Towers had a huge initial damage due to the airplane impact, that broke many columns, also the fuel made a much greater fire that would've been another tipe of fire + an explosion. Obviously, that didn't happened in Dubai's cases.

4) As I understand, the fires in the Dubai's buildings were mostly of the cladding, and not so much of the internal spaces, that means that the temperature is much lower because it is on the facade, the direct contact with exterior air cools continually the structural elements. In the WTC case, fires were internal, so the temperature were higher because it was like an oven, with the heath trapped inside.


In the case of 7WTC, that wasn't hit by a plane, the conclusion of investigations were:

https://en.wikipedia.org/wiki/7_World_Trade_Center

Quote:
NIST determined that diesel fuel did not play an important role, nor did the structural damage from the collapse of the Twin Towers or the transfer elements (trusses, girders, and cantilever overhangs). The lack of water to fight the fire was an important factor. The fires burned out of control during the afternoon, causing floor beams near column 79 to expand and push a key girder off its seat, triggering the floors to fail around column 79 on Floors 8 to 14. With a loss of lateral support across nine floors, column 79 buckled – pulling the east penthouse and nearby columns down with it. With the buckling of these critical columns, the collapse then progressed east-to-west across the core, ultimately overloading the perimeter support, which buckled between Floors 7 and 17, causing the remaining portion of the building above to fall downward as a single unit. The fires, fueled by office contents, along with the lack of water, were the key reasons for the collapse
https://en.wikipedia.org/wiki/File:W...rogression.png


Quote:
After the North Tower collapsed, some firefighters entered 7 World Trade Center to search the building. They attempted to extinguish small pockets of fire, but low water pressure hindered their efforts.[41] Over the course of the day, fires burned out of control on several floors of 7 World Trade Center; the flames visible on the east side of the building.[42][43] During the afternoon, fire was also seen on floors 6–10, 13–14, 19–22, and 29–30.[38] In particular, the fires on floors 7 through 9 and 11 through 13 continued to burn out of control during the afternoon.[8] At approximately 2:00 pm, firefighters noticed a bulge in the southwest corner of 7 World Trade Center between the 10th and 13th floors, a sign that the building was unstable and might collapse.[44] During the afternoon, firefighters also heard creaking sounds coming from the building.[45] Around 3:30 pm, FDNY Chief Daniel A. Nigro decided to halt rescue operations, surface removal, and searches along the surface of the debris near 7 World Trade Center and evacuate the area due to concerns for the safety of personnel
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Old January 10th, 2016, 12:25 AM   #15
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Here's a video explaining why 7WTC fell, it explain that well in a short time. The same user has uploaded a bunch of videos debunking conspiracy teories.

I Understand that people coul feel skeptical with the 7WTC destruction, because indeed looks like an implosion, but if you think of it, what the fire did, was the same explosives do in controlled demolition, destroy the support elements so the rest of the building fall down. In the case of the fire it didn't destroy the column as such, but the heat weakened it at the point it couldn't support the weight of the building above it.

But in the case of twin towers falling down like an implosion, well, they did not, I don't know why people keeps claiming that. At first it may look so, but if you see the videos of the collapse of the Twin Towers, you can see how the lower part tears and rip apart as the upper part crushes it. You can see the building actually opening like a flowers as it is destroyed. Unlike a controlled demolition when it fells relatively intact until it is destroyed as it hits the ground.




I have to put these videos, those are the most moronic conspiration theories I've heard. I can't understand, as I said, people claiming that 7WTC was imploded, Even can understand people claiming the Pentagon was not hit by a plane, But people claiming that no planes hit the WTC and the countless videos we've seen are fake (And I guess they implanted memories on the witnesess) is as moronic as it can be.
I Wnder if that people are really serious.





I am also posting this because I find it pretty interesting. It shows the broadcast of six stations (NBC, CBS, BBC, CNN, FOX, ABC) simultaneously during 15 minutes, from the moment the first plane hit until the second one does. You can see how one by one interrupts their regular programs to report the breaking news, of course not knowing what exactly happened at first. The first one reporting is CNN, the last one is BBC, of course this is located in England, so it is not local news for them.


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Old January 10th, 2016, 01:15 AM   #16
JuanPaulo
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Quote:
Originally Posted by DemolitionDave View Post
Steel has a nearly instantaneous failure mode. Concrete not so much.

The weight of the building and gravity. I make a lot of money off of gravity. It's free.
This is inaccurate. Steel is actually much more ductile than concrete. A ductile steel failure (other than a instability related failure) will show signs of impending failure (yielding) and usually will go in to plastic behavior (permanent deformation) before failure. Concrete, on the other hand, is brittle and fails without any warning. A ductile steel failure will alwyas be more desirable than a brittle concrete failure. That is the way structures are designed, actually.
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Old January 17th, 2016, 07:36 PM   #17
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Quote:
Originally Posted by JuanPaulo View Post
This is inaccurate. Steel is actually much more ductile than concrete. A ductile steel failure (other than a instability related failure) will show signs of impending failure (yielding) and usually will go in to plastic behavior (permanent deformation) before failure. Concrete, on the other hand, is brittle and fails without any warning. A ductile steel failure will alwyas be more desirable than a brittle concrete failure. That is the way structures are designed, actually.

Wrong. I take it you have never demolished a building. It's just the opposite.
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Old January 17th, 2016, 11:53 PM   #18
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Quote:
Originally Posted by DemolitionDave View Post
Wrong. I take it you have never demolished a building. It's just the opposite.
I am a structural engineer. Steel is more ductile than concrete. It is strength of materials 101.

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