any structural engineers or architects?

[red]

reading the 911 false flag thread - Fuji mentioned that the world trade centre used a unique design for its structure.

I have pointed out to you REPEATEDLY that it is not constructed from a compression design like 99.999% of skyscrapers but rather from a suspension design. It was a giant tube shaped cantilever with floors hanging from the frame. Not a building supported by pillars as in all your examples.

You could sensibly argue this is an indictment of that unusual design and serious architects planning similar buildings have looked into that question.

I think only ONE other building was constructed that way and it hasn't been on fire yet. I say think because it is possible two or three more exist, I would have to search.

.

now I didn't want to get into the debate going on there, but I thought this was odd. so I went to wiki and they said:

"The structural engineering firm Worthington, Skilling, Helle & Jackson worked to implement Yamasaki's design, developing the tube-frame structural system used in the twin towers"

when I clicked the link for tube frame structural system- wiki reported:

"In structural engineering, the tube is the system where in order to resist lateral loads (wind, seismic, etc.) a building is designed to act like a hollow cylinder, cantilevered perpendicular to the ground.

The system can be constructed using steel, concrete, or composite construction (the discrete use of both steel and concrete). It can be used for office, apartment and mixed-use buildings. Most buildings in excess of 40 stories constructed since the 1960s are of this structural type."

When I read that I thought, huh, that seems odd.

It went on to discuss Frame Tubed (WTC, AON building), Trussed Tube, and a few other variations. but I didn't get the impression that the WTC design was unique or much different than these other tube frame designs. but I don't know shit about structural design so I wanted to ask the question.

Was the WTC design unique? is the frame tubed design much different than the other variations?

 

[GPIDEAL]

I'm not an architect or engineer but in the construction industry. I'm not sure for all of Toronto's tallest towers except that the the TD towers are traditional reinforced concrete elevator core and structural steel frame with glass curtain wall. It isn't like the WTC. The Bay-Adelaide Centre is reinforced-concrete core including elevator shafts, with structural steel frames around it, and glass curtain wall too. The floors, like the TD towers, are concrete on metal decking. They do not 'hang' from the exterior walls. I would think the BMO tower is the same, only with marble and glass curtain wall. The BNS tower is granite and glass curtain wall, and the RBC tower is glass curtain wall.

 

[basketcase]

...
Was the WTC design unique? is the frame tubed design much different than the other variations?

Mechanical/materials for me but from what I understand, for anything over 70 or so stories, a reinforced concrete design's own weight would lead to unsafe loads on the building so simple concrete-steel designs are cheaper for shorter buildings. Since there are not many buildings above that limit, a tube design is comparatively rare. Hundreds of thousands of reinforced concrete buildings compared to a dozens(?) of tube designs.

 

[red]

So based on what the two of you are saying - then wiki's comment that most buildings over forty stories are tube frame construction is wrong? Is that correct?

 

[james t kirk]

Here is an interview of the Structural Engineer who designed the building.

The Doc is probably about 10 years old, I remember watching it on TV. You can hear the agony in the man's voice. I sit there and I look at him and I feel for him. He's sitting there, an educated man, dressed like you would expect, humble, he's a professional Engineer, he's designing and designed some of the most challenging buildings in the history of mankind. And his heart is full of guilt. Guilt that in no way he deserves.

 

[benstt]

I'm not an architect or engineer but in the construction industry. I'm not sure for all of Toronto's tallest towers except that the the TD towers are traditional reinforced concrete elevator core and structural steel frame with glass curtain wall. It isn't like the WTC. The Bay-Adelaide Centre is reinforced-concrete core including elevator shafts, with structural steel frames around it, and glass curtain wall too. The floors, like the TD towers, are concrete on metal decking. They do not 'hang' from the exterior walls. I would think the BMO tower is the same, only with marble and glass curtain wall. The BNS tower is granite and glass curtain wall, and the RBC tower is glass curtain wall.

Yeah, TD tower isn't a tube design, but doesn't have a concrete core, just a steel one. There are some good pics of the steel frame here:

http://www.blogto.com/city/2011/12/when_the_toronto_skyline_got_its_jolt_of_modernism/

If you're inside a traditional design, you'll notice pillars throughout the floor that you have to plan around. In a tube design, the core and the exterior walls are sufficient, and no pillars between the core and the outside walls.

 

[james t kirk]

Typically in tall building design the elevator core is reinforced concrete of a very strong design. The core is designed to resist the lateral loading of wind and or seismic loads.

Floors then frame into the core.

One of the most efficient ways to brace against wind is "the braced frame". It's simply a steel arrangement were you have a vertical X pinned to adjacent column rows. You can see this type of design in the sears tower in Chicago for example. It's low tech, but it works like a charm.

 

[Ceiling Cat]

I studied structural engineering and took metallurgy courses for three semesters before switching to a related field. In a situation where a plane full of fuel slams into a building above mid level and a fire erupts from the burning fuels on board. There is not an existing structure that would survive since none of this is taken into consideration during the conception, design and construction. A fire at mid level in and building design would have weakened and buckled the steel support columns causing all of the above weight to come down on the lower portion of the building. This would act like a karate chop breaking multiple concrete slabs. The top slab breaking would facilitate the breaking of the lower slabs but only if there is a space between the slabs. If the concrete slabs are place one on top of each other with no space then it becomes much harder to break. This was exactly what happened at the WTC incident. This would be true if it would have been any other structural design.



In the above GIF you can see on the graph after the karate chop the initial impact breaks the first slab, the lower slabs are broken by the weight of the first slab breaking.

The collapse of the WTC is not evidence of any government conspiracy



What happened at the WTF incident is exactly what would have happened in a controlled implosion of a structure. The supports are knocked out and the weight of the building is used to take down the structure.

 

[TESLAMotors]

Funny thing about the jet fuel...it burns up REAL fast.....oh, like let's say the way it did on IMPACT of the WTC buildings?
Remember those huge balls of fire, ALMOST INSTANTLY.
Fire rated office furniture? Burning?
Perhaps, but you throw in some sheets of paper, carpeting, wood (furniture) then yeah, you'll get some temperatures high enough to build steel. LMAO
That's why they USE steel to build buildings, because of the temperatures required for it to compromise are so high, office fires can't bring them down. Otherwise we wouldn't have high rises.


Check out the 2nd post, the 1st one is good as well, but post #2 well, there are numbers there for those who don't like math and science.
http://pilotsfor911truth.org/forum/index.php?showtopic=28


Post #2
Some interesting information..
-1535ºC (2795ºF) - melting point of iron
-1510ºC (2750ºF) - melting point of typical structural steel
-825ºC (1517ºF) - maximum temperature of hydrocarbon fires burning in the atmosphere without pressurization or pre-heating (premixed fuel and air - blue flame)

Diffuse flames burn far cooler.
Oxygen-starved diffuse flames are cooler yet.
The fires in the towers were diffuse -- well below 800ºC.
Their dark smoke showed they were oxygen-starved -- particularly in the South Tower.

Maximum jet fuel burn temperature is 825 Celsius.
Temperature needed to melt structural steel is 1510 Celsius

 

[TESLAMotors]

A fire at mid level in and building design would have weakened and buckled the steel support columns

Temperatures in excess of over 1500C - so carpeting, office furniture, some wiring, yeah, I can see that becoming 1500C.

In the above GIF you can see on the graph after the karate chop the initial impact breaks the first slab, the lower slabs are broken by the weight of the first slab breaking.

Let's not forget the hand that follows through all the way down now. His hand doesn't just stop after breaking the first slab.

The collapse of the WTC is not evidence of any government conspiracy

When they (government) tell you (via NIST reports) that WTC#7 fell because ONE SINGLE column of the building was compromised by fire and debris, yeah, that's bullshit.
Add to that, the one column would have to burden a very large portion of the building load, because AMAZINGLY, it fell straight down on its own footprint, LIKE many controlled demolitions do.
Example of a controlled demolition

WTC#7
After ONE column was compromised due to fire and debris. Remember, that fire would need to be in excess of over 1400C and it would have to manage the majority load of the building since once it buckled the whole building fell on its own footprint.

So ONE COLUMN weakens and the building falls nearly straight down, perfectly.
AMAZING, just amazing.

Fire and debris caused damage to ONE column and the result is the above. lol

So remember kids, believe everything the government tells you, because they'll be honest with you. They have professionals on their side.

 

[KBear]

Temperature needed to melt structural steel is 1510 Celsius

Doubt it will matter to you as you will just go off in another direction, but others might be interested in the facts and science.

Structural steel loses its strength at well below its melting point. One of the reasons steel beams in buildings are insulated is to give them some protection from the heat of a fire.

http://www.engineeringtoolbox.com/metal-temperature-strength-d_1353.html

In newer homes you often see vertical steel beams used in the basement to support the floor above, older homes use wooden beams. In a fire the steel beams will quickly buckle, where as the thick wooden beams will withstand the heat of a fire for a bit longer.

 

[Experienced1]

Too many factors

200 ton plane on impact
plane going 450 - 500 mph
jet fuel burning

The Structural engineer in that video said that they accounted for a plane crash in the design / engineering phase of the WTC but the plane they used on their calculations was not as heavy and going as fast as the ones that crashed in the WTC , and they did not account for the jet fuel.

And if you see the steel colums and beams there are no fire spray left on them when they are being examined .


i have saved that url adrdess because i am in commercial construction, and i love this kind of research

THanks for posting that video

i have found another short video / animation of how it affected the structure


https://youtu.be/n8pOuler95c

 

[shakenbake]

Funny thing about the jet fuel...it burns up REAL fast.....oh, like let's say the way it did on IMPACT of the WTC buildings?
Remember those huge balls of fire, ALMOST INSTANTLY.
Fire rated office furniture? Burning?
Perhaps, but you throw in some sheets of paper, carpeting, wood (furniture) then yeah, you'll get some temperatures high enough to build steel. LMAO
That's why they USE steel to build buildings, because of the temperatures required for it to compromise are so high, office fires can't bring them down. Otherwise we wouldn't have high rises.


Check out the 2nd post, the 1st one is good as well, but post #2 well, there are numbers there for those who don't like math and science.
http://pilotsfor911truth.org/forum/index.php?showtopic=28


Post #2
Some interesting information..
-1535ºC (2795ºF) - melting point of iron
-1510ºC (2750ºF) - melting point of typical structural steel
-825ºC (1517ºF) - maximum temperature of hydrocarbon fires burning in the atmosphere without pressurization or pre-heating (premixed fuel and air - blue flame)

Diffuse flames burn far cooler.
Oxygen-starved diffuse flames are cooler yet.
The fires in the towers were diffuse -- well below 800ºC.
Their dark smoke showed they were oxygen-starved -- particularly in the South Tower.

Maximum jet fuel burn temperature is 825 Celsius.
Temperature needed to melt structural steel is 1510 Celsius

Dude, looking solely at the melting point of a metal will not accurately or adequately predict structural behaviour. you have to look at the structural strength behaviour a sthe temperature increases. At what temperature will the metal behave like a 'plastic'? As an example, aluminum and other metallic extrusion does not require a metal to melt, but to soften almost like a 'putty' in very crude and basic terms. This probably happened to more than just one column/beam/structural member in the WTC tragedy.

 

[Titalian]

Oh for Gawds sake, there is not one high rise structure in the world that has fallen due to fire, all of a sudden 3 in a row.

 

[TESLAMotors]

Dude, looking solely at the melting point of a metal will not accurately or adequately predict structural behaviour. you have to look at the structural strength behaviour a sthe temperature increases. At what temperature will the metal behave like a 'plastic'? As an example, aluminum and other metallic extrusion does not require a metal to melt, but to soften almost like a 'putty' in very crude and basic terms. This probably happened to more than just one column/beam/structural member in the WTC tragedy.

No, I'll bite and give you that - forget the melting point factor.

But ONE column in building 7 softens and the ENTIRE building fails and in turn collapses?
Guess it carried well over 90% of the load AND THEN collapsed symmetrically straight down.

Unbelievable. Those guys at NIST sure know their (bullshit) stuff and know people are gullible enough to buy into it.

 

[TESLAMotors]

Esa

Oh for Gawds sake, there is not one high rise structure in the world that has fallen due to fire, all of a sudden 3 in a row.

Yah, everything failed day. Lol
But they had (modified) airliners breaking the sound barrier, one good thing to come of all this I suppose. :biggrin1:

 

[KBear]

Oh for Gawds sake, there is not one high rise structure in the world that has fallen due to fire, all of a sudden 3 in a row.

Buildings fail all the time during a fire. The reason the supporting structure in buildings is protected some from fire is to give people a chance to escape before the building collapses.

http://news.nationalpost.com/news/w...r-building-collapse-in-new-yorks-east-village

 

[Promo]

There's been several good TV shows describing why the WTCs collapsed and they all basically agree which is reassuring.
Nova: https://www.youtube.com/watch?v=KPqxJpykW00

I studied structural engineering and took metallurgy courses for three semesters before switching to a related field. In a situation where a plane full of fuel slams into a building above mid level and a fire erupts from the burning fuels on board. There is not an existing structure that would survive since none of this is taken into consideration during the conception, design and construction. A fire at mid level in and building design would have weakened and buckled the steel support columns causing all of the above weight to come down on the lower portion of the building. This would act like a karate chop breaking multiple concrete slabs. The top slab breaking would facilitate the breaking of the lower slabs but only if there is a space between the slabs. If the concrete slabs are place one on top of each other with no space then it becomes much harder to break. This was exactly what happened at the WTC incident. This would be true if it would have been any other structural design.

As usual the cackling head Ceiling Cat got it wrong. As others have already described, the WTC was a tube design with each floor connected to the core and outside structural frame. This design allows for no steel support columns on each floor, thus the entire floor space can be used for office space (one of the big selling features of the building). If no steel support columns existed, how could they have "weakened and buckled .... causing all of the above weight to come down". It was the steel structure supporting the floor that weakened and sagged due to the blown-off insulation and heat from the fire. The joints that connected the floor's steel structure to the core and outside structure were not designed for that type of load and the joints failed as the floor sagged.

Karate chop example is also incorrect. When the buildings started to collapse, the first failing floor "pancaked" onto the already weakened floor below and a combination of; the energy and weight of the falling floor, the weakening of the steel supporting the lower floor, the weakened joints and the lack of supporting columns allowed a cascading effect to start. (The floors fell level, another reason the karate example is wrong). The additive weight of all collapsed floors, increasing speed of collapse and lack of support columns kept the cascade going even on undamaged floors. Also explains why the collapse was straight down. After the collapse, sections of the outside structure stood 12 stories tall - basically the inside of the building collapsed independently of the core and outside structure.

 

[Ceiling Cat]

Promo,

There are too many variables and no previous events to compare the collapse of these buildings to. Experts far more qualified than guys on TERB can not give you an answer. So you can debate till you cackler gonads fall off and you will still not know what truly happened. Your explanation is another explanation of my explanation. Did you use to cheat in school and copy up other people work in your own words?

BTW- I will debate any subject, but if you start to cackle. I am not interested.

 

[Titalian]

From Architectural and Engineering experts. If you dare listen. On PBS !