WTC7: Did the fires burn long and hot enough?

[Jazzy]

Wouldn't a thick piece of steel that got hot enough to soften retain that property for a while (ie, several hours)? Seems fair.

No. I agree with Lee. (Bet no-one imagined that might happen! )

But Cairenn is correct. The steel grain structure is controlled by heating and quenching during production to produce a semi-hard state. Because it receives some welding prior to and during construction it cannot be made too hard, though the harder it is the stronger it will be. There is a compromise there that always has to be considered.

Consequently, fire will damage the steelwork, reducing its strength somewhat once it has cooled down - if the austenitic temperature was reached by the steel before it cooled.

If it wasn't reached, the steel would not be affected at all.

 

[Jazzy]

Ok. Third time lucky. This is not 'personal' (how could it be?)

Haha.

Imagine a fifteen year old has some homework on what happens to structural steel after it's been heated and cooled. She Googles her question and up pops your one paragraph, unequivocal statement of fact: "If the steel got to the softening temperature, then it stayed soft and deformable". And said fifteen year old, happy in her new-found knowledge, goes with that. What mark do you think she might get?

Full marks.

It worries me that your answer to my subsequent question, Do you think it is right?, was: "Soft in metal has a different meaning than it does in pillows" plus irrelevancies about other metals.

Hm. I don't agree.

The way steel in the manufacturing process is cooled has an effect on the type of steel produced - its flexibility, stiffness, hardness - ductility etc.; but you said: "If the steel got to the softening temperature, then it stayed soft and deformable".

Actually Cairenn is correct.

in the context of a building fire. Will you accept it is an incorrect statement in this context and in every other possible context?

There is a choice here, Lee, as to whether you are bullying Cairenn or just plain ignorant. I cannot tell.

Especially in the context of WTC7's fire, structural steel heated above its austenitic temperature would have softened, because it was never quenched.

I think that 'knowledge' is what makes many people fearful

I think ignorance beats knowledge in that respect.

 

[Jazzy]

All you do is bait and insult... back up what you say and stick to the question in hand.

It must irritate you to have to disappear in your mind all the engineering examples and info I provide to reach the imagined insults. Sympathy once more extended. I try to be as brief as I can.

What you call 'insulting NIST and those who support them' is known as due process

What? "Due process" had already taken place by the time it was published. By qualified engineers with hundreds of years of experience between them.

and peer review

You have to allow me to laugh here. You ain't no "peer"! Get out of here! LOL.

 

[Met Watch]

Jazzy, Oxy, and Lee - last warning, guys. Keep it civil and cool it with the insults, or infractions will start piling up for all of you.

 

[Jazzy]

Would you explain why you keep posting this video and specifically why you feel it is relevant to the topic?

[video=youtube_share;mFNe_pFZrsA]http://youtu.be/mFNe_pFZrsA[/video]

With additional pleasure (I've stayed up for it!)

You are looking at Newton's Cradle. It demonstrates the almost loss-free and instantaneous transfer of kinetic energy through a set of STEEL BALLS.

Now imagine a ragged pile of STEEL BEAMS, resting on a concrete base, onto which another STEEL BEAM falls.

To where is the kinetic energy of the falling beam going to be applied?

THE CONCRETE BASE.

Yes, some of the energy will reflect back, but over the short time of the collapse the majority of the energy will be found at the base, as HEAT.

Would you also confirm that you now accept 'buckling', does not mean inevitable collapse as you previously stated?

No.

You have showed me buckled columns that only fell so far because they were still attached to an unbuckled structure - the CONCRETE one that's out-of-frame.

WTC 7 might have done the same if its core had been made of RC. But all the internal columns depended on the same collapsing floors to maintain their stability.

I can see you still do not understand buckling instability. Why don't you spend a tad more than no time at all to study this?

 

[Grieves]

Apart from the implied double insult to the NIST engineers and all the world's engineers who agree with the NIST Report, including myself, no. But those are constant insults with you.

Is that the source of your attitude? That I and others like me think you might be wrong? It's an insult to you that I think you might be wrong?

Certainly not. I was being sympathetic. My sympathy might increase were you not to be so unwilling to understand anything.

and you can't stop, can you? The snide, sarcastic refusal to even admit you're being insulting, followed by another insult.
I think I understand now, at least. A criticism of the official account is to you an attack on your professional opinion, an attack on your ego... something you apparently can't cope with in a civil manner.

 

[Mick West]

Please try to stick to facts people. If you want to discuss each other, then take it elsewhere.

 

[Jazzy]

Is that the source of your attitude? That I and others like me think you might be wrong? It's an insult to you that I think you might be wrong? and you can't stop, can you? The snide, sarcastic refusal to even admit you're being insulting, followed by another insult. I think I understand now, at least. A criticism of the official account is to you an attack on your professional opinion, an attack on your ego... something you apparently can't cope with in a civil manner.

It's off-topic.

If there's a flame pit here, start this as a topic, and see what I have to say.

If you dare.

 

[Cairenn]

Jazzy has a theory and he has been able to offer a considerable amount of evidence to support it.

What is the other theory? Oh yes that somehow the buildings were rigged for implosion, with NOTHING to support how that could have been done. No evidence of how they could have been planted, Who would have planted them (implosion is a specialty field) How the wiring or detonators could have survived the fire. How they knew where the fires would start? and on and on and on.

His is logical, and has evidence the other one is just opinions.

 

[Oxymoron]

Please try to stick to facts people. If you want to discuss each other, then take it elsewhere.

I agree with this statement but the fact is certain people seem unable to do this and insist on making personal attacks in a gaslighting fashion, thereby subverting and disrupting the topic. I think Grieves has hit on a very important reason for this and unless it is addressed, it appears the attacks and disruption will continue. I appreciate the difficulty but do you have any practical suggestions for preventing the attacks as the root cause appears deep seated and unabated despite appeals to desist.

 

[George B]

I agree with this statement but the fact is certain people seem unable to do this and insist on making personal attacks in a gaslighting fashion, thereby subverting and disrupting the topic. I think Grieves has hit on a very important reason for this and unless it is addressed, it appears the attacks and disruption will continue. I appreciate the difficulty but do you have any practical suggestions for preventing the attacks as the root cause appears deep seated and unabated despite appeals to desist.

The Mods will be assessing infractions. . . I ask all to cool off and begin again . . . Please forget the past and let's go forward from here. . . .Thanks!

 

[lee h oswald]

No. I agree with Lee. (Bet no-one imagined that might happen! )

But Cairenn is correct. The steel grain structure is controlled by heating and quenching during production to produce a semi-hard state. Because it receives some welding prior to and during construction it cannot be made too hard, though the harder it is the stronger it will be. There is a compromise there that always has to be considered.

Consequently, fire will damage the steelwork, reducing its strength somewhat once it has cooled down - if the austenitic temperature was reached by the steel before it cooled.

If it wasn't reached, the steel would not be affected at all.

But Cairenn is correct

No, unequivocally. The claim: If the steel got hot enough to become soft and deformable then it stayed that way. That is completely incorrect. The cover story for this incorrect statement is all about annealing, and reaching the austenitic temperature. Annealing of steel is a manufacturing process used to control the ductility of the end product, as I said in a previous post. The austenitic temperature of steel is dependent on its alloy/carbon content, but hangs out around the 1600F mark, which is around 850 celcius. The temperatures must be very closely controlled over a sustained period - around twenty hours for the whole process from heating to sustaining heat to allowing to cool - otherwise it doesn't work. After being raised to the correct temperature the steel is allowed to remain at that temperature for another 4-5 hours and then it is cooled in a controlled environment, ie. usually inside the furnace. The cooling must not exceed 100f per hour, so 1600f cooling time? A minimum of 16 hours. All previously fabricated members must be re-annealed to restore required ductility around areas where the steel has been bent, twisted, shaped, rolled etc to achieve the required shape for its intended purpose (all that banging about makes it brittle).

Add to that the atmospheric conditions required for correctly annealing, and you know tht this process could not possibly have taken place by accident inside building 7 - which is the subject of the thread:

http://heattreatment.linde.com/Inte...orybyalias/apps_annealing/$file/Annealing.pdf

Atmospheres


Although most steel is annealed in nitrogen/hydrogen, this atmosphere is

inherently decarburizing to steels. If it is necessary to avoid decarburization

then different atmospheres can be used as shown in the table.

Material Atmosphere



Cast Iron --- Nitrogen

Mild Steel --- Nitrogen/2-4% Hydrogen

Alloy Steels --- Nitrogen/2-4% Natural Gas

Carbon Steel --- Nitrogen/2-4% Natural Gas

Carbon Steel --- Nitrogen/0.5-1% Propane

Mild/Carbon Steels --- Nitrogen/5-50% Cracked Methanol or Endothermically generated gas



While the nitrogen/hydrocarbon atmospheres require no control the furnace

needs to be very leak tight for them to be effective. If carbon control is

needed then a mixture of nitrogen with cracked methanol or endothermically

generated gas can be used...

http://www.simplytoolsteel.com/heat-treating-annealing-tool-steel.html

Steel tool making

Most steel produced at a mill, is supplied to the service center or end user in the annealed condition. During the manufacturing of steel bars and plates, steel undergoes tremendous stress. It is heated, bent, squeezed and rolled. This is performed repeatedly until it reaches its final shape. During these processes, the steel loses its ductility and malleability. One of the final processes in the production of steel is annealing. It is heated above its critical temperature and held there for a number of hours to return it to its original ductile and malleable condition. As a final step, most steel will undergo a machining or peeling operation to remove any decardurized layer that has been formed on the outside of the bar or plate.

http://www.akamaiuniversity.us/PJST10_2_149.pdf ---

INTRODUCTION
Annealing describes a number of different heat treatments, which can be applied to

metals and alloys. The cold-worked state is a condition of higher internal energy than the

undeformed metal. Although the cold worked dislocated cell structure is mechanically stable, it is not

thermodynamically stable (4). With increasing temperature, the cold worked

state becomes more and more unstable. Eventually the metal becomes soft and

returns to a strain-free condition.


Annealing is very important commercially because it restores the ductility to a metal

which has been severely strain-hardened. Therefore, by interposing annealing

operations after several deformations on a metal, it is possible to regain its metallic

structure to a great extent

ANNEALING


Annealing was carried out at temperature for recrystallization, grain-growth, and stress

relief. The three samples were subjected to heat treatment of 650ºC, 700ºC, and 850ºC,

respectively.

•
Sample A, was annealed to temperature
650ºC,

•
Sample B, annealed to temperature
700ºC,

•
Sample C, annealed to a temperature of
850ºC,

•
Sample D, served as the control experiment or specimen "as received".


Each sample underwent annealing at the different temperatures as stated above and

were left to cool in the furnace which took approximately 72 hours each. Samples of
about 35mm were cut of from each of the annealed samples including the control

(sample D) for hardness tests and metallographic structure all to identify what

happens to steel product after undergoing heat-treatment at different temperatures

Hopefully it's now absolutely clear that annealing is a restorative manufacturing process steel is subjected to in order to make it workable - annealed steel is what you work with - once work-hardened it is no longer safely workable for drilling, bending, shaping etc., annealed is the condition required for greater ductility. In the case of structural steel that would greatly affect is ability to deflect (bend) under load, otherwise it's not suitable because it's too rigid and brittle. It has nothing to do with the claim that once steel is made 'soft and deformable' by heat it remains that way, which is obviously incorrect.

Strength after heating and cooling?

http://civil.iisc.ernet.in/~manohar/Fire/Part-23_Materials.pdf

Pre-stressing steel does regain its strength upon cooling to the same degree as hot-rolled steel

Most of the steel used in 7 would be rsj = rolled steel joist.

http://phoenix-investigations.com/rebuilding-after-a-fire-by-michael-hayes-pe/ ---

Steel Evaluations
Steel is a bit less straightforward to analyze after a fire. If steel is exposed to temperatures of approximately 1200°F, metallurgical changes can occur. The changes are usually only temporary and once the steel cools, it can regain nearly 100% of its pre-fire strength. Although the steel may have regained most of its pre-fire strength, it may have been distorted or dimensionally changed by the fire or embrittled due to rapid cooling associated with fire-fighting efforts.

Clearly, the temperatures and controls inside building 7 don't relate either to the process of annealing nor to the false claim that once steel is heated to the point of being 'soft and deformable', it remains that way. Beware: chop-logic at work.

 

[Oxymoron]

Fire safety standards:

The debris field resulting from the collapse of WTC 7.
Fireproof construction is the design concept that a building should survive total burnout without collapse. Total burnout occurs when a fire continues until all combustible material is consumed. The concept of fireproof construction formed the basis of early fire codes. The 1942 report, Building Materials and Structures: Fire Resistance Classifications of Building Constructions, issued by the National Bureau of Standards, defined fireproof construction as a design where "the structural elements are of incombustible materials with fire resistance ratings sufficient to withstand the fire severity resulting from the complete combustion of the contents and finish involved in the intended occupancy." The minimum required resistance was four hours.
The current International Building Code is based solely on a prescriptive fire resistance rating. The code requires that tall buildings be designed to resist fire for a duration of three hours. No additional calculations are required based on framing style or combustible content. In order to determine whether these reductions in the required fire resistance rating and the repeal of building specific analysis were warranted, it is helpful to look back at the development of the current standards along with contemporary examples of building fires.
Historical Overview

At the beginning of the 20th century, fire engineering was created to save lives and to avoid the total collapse of a building due to a fire burnout. Fire engineers and structural engineers worked together and, through experimental testing and common sense, developed a set of prescriptive rules that satisfied their goal so successfully that no additional testing was required.
As the initial challenge was solved, fire and structural engineering professionals focused their efforts on further endeavors to protect building occupants and contents. The development of sprinklers and other fire suppression and compartmentalization measures have been very effective, saving lives, controlling the spread of fire, and limiting economic losses. These efforts were helped by The Society of Fire Protection Engineers (SFPE), created in 1950, which has as one of its goals "applying scientific and engineering principles to protect people and the environment from destructive fire."
However, the prescriptive requirements developed in the early 1900s may no longer be accurate indicators of building safety during fire. Over time, they have been expanded for application to new materials and assemblies. Behavior of these new components and materials is determined through testing. The response of the entire system is then extrapolated from the component behavior. Although this approach is usually reasonable, its validity for new methods of construction - such as those using larger bay sizes, different and lighter materials, and different connections - is unclear. The assembly may react differently than what is predicted from the behaviors of its individual components considered independently. Unfortunately, the American Society for Testing and Materials (ASTM), which details procedures for fire testing of components, does not address the impact of fire on the integrated structural system.
Our European counterparts have conducted full-size fire tests in Cardington, UK, demonstrating the satisfactory behavior of steel structures under total fire burnout. Unfortunately, in the US, steel connection types differ from, and are not as strong as, the British connections that have axial strength requirements. Therefore, the UK tests cannot be applied directly to structures in the US. To date, full-size building tests have not been conducted in the US. Such tests could verify whether current design practices are sufficient protection in the event of a total burnout. They could also reveal the strengths and weaknesses in common building design practices.

http://www.structuremag.org/article.aspx?articleID=529

This section is very interesting,

As the initial challenge was solved, fire and structural engineering professionals focused their efforts on further endeavors to protect building occupants and contents. The development of sprinklers and other fire suppression and compartmentalization measures have been very effective, saving lives, controlling the spread of fire, and limiting economic losses. These efforts were helped by The Society of Fire Protection Engineers (SFPE), created in 1950, which has as one of its goals "applying scientific and engineering principles to protect people and the environment from destructive fire."

It appears to be saying that sprinklers were introduced not as a method of saving the building from collapse by fire but simply to ensure minimum loss of life.

This is an important point because much is made of the inaction of the sprinkler system being integral to the WTC's failure. This is apparently far from the case.

The last paragraph is also very interesting as it suggests the steel connections are not as strong as U.K and that the U.S undertakes no full fire experiments which is pretty poor considering the money spent on military etc and the high number of high rise buildings in the U.S.

 

[lee h oswald]

Lee, your ignorance of metallurgy is astounding. Cairenn has provided you with a wealth of information, but you insist on being willfully ignorant.

A steel beam is hardened to a specific level to provide strength and flexibility depending on its intended use. If you heat steel to red hot and let it air cool it is annealed, the crystalline structure of the steel has cooled to a random mass. If you beat it with a hammer, you work-harden it. This is the same process as taking a soft steel hanger and bending it back and forth until it breaks. Each time you bend it, you align the crystalline structure a little more and harden it until it becomes brittle and breaks.

Structural steel is heat tempered to harden it. Steel is heated to a specific temperature to allow the crystalline structure to align in a certain way and the temperature is slowly reduced over hours, sometimes days, so the alignment remains unchanged during cooling.

Lee, your ignorance of metallurgy is astounding. Cairenn has provided you with a wealth of information, but you insist on being willfully ignorant.

Is that an attempt to be courteous?

But the question is simple: The claim is that once steel is heated to a point that it is 'soft and deformable' it remains that way - that's wrong, isn't it? Please do provide your answer - that is the question we are discussing.

In your post, you're conflating annealing with heat treatment with tempering - and generally getting the whole fabrication process all mixed up. It's quite a particular and precise methodology required to produce different types of steel for different applications - not as simple as heating steel to 'red hot' and letting it air cool. There's a few good links up there ^^^ you might like to read to get a better idea of the whole anneal deal.

But I'd really appreciate your answer to the main question as it's pertinent to the thread and I think it's important that presentations suggesting that steel after being heated remains 'soft and deformable' upon cooling should be clarified, it's quite a simple point, and nothing to do with annealing.

 

[SR1419]

The last paragraph is also very interesting as it suggests the steel connections are not as strong as U.K and that the U.S undertakes no full fire experiments which is pretty poor considering the money spent on military etc and the high number of high rise buildings in the U.S.

I agree;

Our European counterparts have conducted full-size fire tests in Cardington, UK, demonstrating the satisfactory behavior of steel structures under total fire burnout. Unfortunately, in the US, steel connection types differ from, and are not as strong as, the British connections that have axial strength requirements

 

[lee h oswald]

Fire safety standards:
Our European counterparts have conducted full-size fire tests in Cardington, UK, demonstrating the satisfactory behavior of steel structures under total fire burnout. Unfortunately, in the US, steel connection types differ from, and are not as strong as, the British connections that have axial strength requirements. Therefore, the UK tests cannot be applied directly to structures in the US. To date, full-size building tests have not been conducted in the US. Such tests could verify whether current design practices are sufficient protection in the event of a total burnout. They could also reveal the strengths and weaknesses in common building design practices. [/EX]

It appears to be saying that sprinklers were introduced not as a method of saving the building from collapse by fire but simply to ensure minimum loss of life.

This is an important point because much is made of the inaction of the sprinkler system being integral to the WTC's failure. This is apparently far from the case.

The last paragraph is also very interesting as it suggests the steel connections are not as strong as U.K and that the U.S undertakes no full fire experiments which is pretty poor considering the money spent on military etc and the high number of high rise buildings in the U.S.

Not sure about the veracity of US not conducting full fire tests etc.....seems bit of a stretch - I wonder how they draw up codes without the data?

But anyway, as far as the quality of wtc steel goes, much of it was made in Japan - and the Japanese make the best steel.

The core columns were steel box-columns that were continuous for their entire height, going from their bedrock anchors in the sub-basements to near the towers' tops, where they transitioned to H-beams. Apparently the box columns, more than 1000 feet long, were built as the towers rose by welding together sections several stories tall. The sections were fabricated by mills in Japan that were uniquely equipped to produce the large pieces. 2 ​

http://911research.wtc7.net/wtc/arch/core.html

 

[SR1419]

Not sure abot the veracity of US not conducting full fire tests etc.....seems bit of a stretch - I wonder how they draw up codes without the data?

But anyway, as far as the quality of wtc steel goes, much of it was made in Japan - and the Japanese make the best steel.

The core columns were steel box-columns that were continuous for their entire height, going from their bedrock anchors in the sub-basements to near the towers' tops, where they transitioned to H-beams. Apparently the box columns, more than 1000 feet long, were built as the towers rose by welding together sections several stories tall. The sections were fabricated by mills in Japan that were uniquely equipped to produce the large pieces. 2 ​

but doesn't that quote refer to WTC 1&2?

Do we know the same can be said about WTC7 since it was built 20yrs later?

 

[George B]

but doesn't that quote refer to WTC 1&2?

Do we know the same can be said about WTC7 since it was built 20yrs later?

Good question . . . was WTC7 built under newer standards . . . was it stronger or weaker than WTC1&2 . . . ???

 

[Cairenn]

lee, worked harden steel can be annealed. I have done it at home. I have worked with cold and hot forming metal. I do KNOW what I am talking about. So does Roland.

I never said that I knew that annealing is what happened in the WTC buildings. I was pointing out that it was a possibility.

And annealed steel remains workable after it cools.

You have been given the necessary information and you choose to ignore it. So be it. Your mind is made up. There is no reason for me or others to waste our time with you.

Do not expect any more responses from me. You go on the ignore list. Bye.

 

[lee h oswald]

but doesn't that quote refer to WTC 1&2? Do we know the same can be said about WTC7 since it was built 20yrs later?

Towers open for business in 73, 7 in 87. Towers took longer to build, ofcourse.

It does refer to the towers, but the link says wtc7, so I claim immunity! Seriously, the point is that this is The World Trade Center we're talking about - the prestige building project of its time - not Chipmunk County General Store - it's the boom shakalaka! That's a technical term - I'll look for a link....

 

[lee h oswald]

lee, worked harden steel can be annealed. I have done it at home. I have worked with cold and hot forming metal. I do KNOW what I am talking about. So does Roland.

I never said that I knew that annealing is what happened in the WTC buildings. I was pointing out that it was a possibility.

And annealed steel remains workable after it cools.

You have been given the necessary information and you choose to ignore it. So be it. Your mind is made up. There is no reason for me or others to waste our time with you.

Do not expect any more responses from me. You go on the ignore list. Bye.

worked harden steel can be annealed.

Yes, it is annealed in order to render it workable from its hardened state after being worked before!

I never said that I knew that annealing is what happened in the WTC buildings. I was pointing out that it was a possibility.

No, but you used it an excuse for what you did say. And annealing was never possible in wtc7 - obviously.

I do KNOW what I am talking about

If so, why this?

And annealed steel remains workable after it cools

The whole point of annealing is that it is the process which renders steel workable and usable, and it's deliberate - otherwise your piece wouldn't be fit to work with - the final process a structural steel goes through after fabrication (bending, rolling - all that) is annealing - it's a bit like healing, really - restoring it to its original ductility in order to make the thing viable. There are degrees of heat treatment (annealing) depending on the qualities you want from your steel.

You have been given the necessary information and you choose to ignore it. So be it. Your mind is made up.

Do not expect any more responses from me. You go on the ignore list. Bye.

Promise?

 

[Oxymoron]

In September 2009, Judge Edward Lehner was hearing arguments on whether to allow New Yorkers to vote on a proposal to investigate the attacks on the World Trade Center. Sponsored by NYC CAN, the petition included the signatures of 52,000 residents (Villager 8/4/09). When Judge Lehner remarked that the 9/11 Commission had already completed an investigation, the group's attorney, Dennis McMahon, replied that the Commission had left many questions unanswered. "One of the biggest questions," the lawyer noted, "is why did Building 7 come down?" Puzzled, Judge Lehner asked "Building what?" McMahon informed the judge that a third World Trade Center skyscraper, Building 7, also came down on 9/11.

One national poll found that 43 percent of Americans weren't aware that three buildings had fallen (Zogby Intl. 5/24/06); of this number, only a small percentage had any idea about the circumstances. Even among those who were more knowledgeable, the disintegration of this third skyscraper has remained an enigma.

http://www.mountingevidence.org/chapter-22.html

I would like to refer back to post 183 and recap on known facts.

https://www.metabunk.org/posts/43998

I think some core issues in regard to did the fires burn hot and long enough at wtc 7 have been raised in this thread.

1) It is the only steel-framed high-rise building in the known universe to have collapsed because of fire alone, (1 & 2 being conflated by the plane impacts)(NIST acknowledge impact damage from debris was not a contributing factor to 7's collapse), NIST subsequently ruled out diesel fuel from Con Ed as a contributing factor)
2) Other instances of partial building collapse have had important mitigating circumstances, weak roof trusses, no fire protection, lightweight steel, in construction or repair/refurbishment etc
3) 7 had immense columns and girders, (which increases fire resistance)
4) 7 had impeccable fire retardant on all columns and girders, (no other steel framed building with such strong, let alone well protected steels, has collapsed even partially)
5) 7 had a modest fuel loading of around 32kg per square metre
6) Load tranference, (alternate load pathways), which even if there was an unprecedented partial collapse, would preclude a total collapse, especially a straight down symmetrical collapse as witnessed.

http://www.fema.gov/pdf/library/fema403_ch5.pdf

5.2.3

Transfer Trusses and Girders
The transfer trusses and girders, shown in Figure 5-6, were located between the 5th and 7th floors. The function and design of each transfer system are described below.


Truss 1 was situated in the northeast sector of the core, and spanned in the east-west direction. As shown in Figure 5-7, this truss was a two-story double transfer structure that provided load transfers between nonconcentric columns above the 7th floor to an existing column and girder at the 5th floor.

The girder then provided a second load transfer to an additional two columns.


The 7th floor column supported 41 floors and part of the east mechanical penthouse. Its load was transferred through the triangular truss into a column located above an existing substation column and girder at the 5th floor.

The 36.5-ton built-up double web girder spanned in the north-south direction between two new columns that started at the foundation and terminated at the 7th floor.

The truss diagonals were W14 shapes and the horizontal tie was a 22-ton, built-up shape.

Fire

It should be noted that the Bankers Trust Building sustained impact damage but did not catch fire!

http://www.debunking911.com/pull.htm .... Would have you believe that the decision to evacuate the area was made around 3.00 to 4 p.m and yet there are numerous accounts of an evacuation of the surrounding area from noon to 1 p.m.

Here is more evidence they pulled the teams out waiting for a normal collapse from fire...

"The most important operational decision to be made that afternoon was the collapse (Of the WTC towers) had damaged 7 World Trade Center, which is about a 50 story building, at Vesey between West Broadway and Washington Street. It had very heavy fire on many floors and I ordered the evacuation of an area sufficient around to protect our members, so we had to give up some rescue operations that were going on at the time and back the people away far enough so that if 7 World Trade did collapse, we [wouldn't] lose any more people. We continued to operate on what we could from that distance and approximately an hour and a half after that order was [given], at 5:30 in the afternoon, World Trade Center collapsed completely" - Daniel Nigro, Chief of Department

"Then we found out, I guess around 3:00 [o'clock], that they thought 7 was going to collapse. So, of course, [we've] got guys all in this pile over here and the main concern was get everybody out,
​

So when were the first observed fires?

http://www.mountingevidence.org/chapter-22.html

The question of when the fires first broke out is also controversial. The standard analysis of WTC-7 asserts that when the North Tower came down at 10:28, flying debris ignited the fires. Although WTC-7 stood 325 feet away, tremendous mushrooming explosions at the top of the Tower propelled large chunks of metal, some of them likely superheated, hundreds of feet outward (www.youtube.com/watch?v=EgN080yySe0).

For the first two or three hours, the blazes were scattered and not immediately visible. NIST also acknowledged that the first photographs or videos of WTC-7 fires were taken at about 12:10 a.m., and that two other photos were taken at 12:28.

 

[Cairenn]

Civilians were evacuated earlier, the later time is when the firefighters were pulled back.

 

[Oxymoron]

Civilians were evacuated earlier, the later time is when the firefighters were pulled back.

Can you authenticate that?

The quote says "Then we found out, I guess around 3:00 [o'clock], that they thought 7 was going to collapse."

 

[Oxymoron]

You are looking at Newton's Cradle. It demonstrates the almost loss-free and instantaneous transfer of kinetic energy through a set of STEEL BALLS.

Yes I realise what it is... but it is demonstrating transfer of energy through motion. It has nothing to do with heat generation or the calculation of. I therefore suggest it is an irrelevant example.

Now imagine a ragged pile of STEEL BEAMS, resting on a concrete base, onto which another STEEL BEAM falls.

Yes a totally different concept but as you admit, there is not one example of vast amounts of heat and/or instantaneous combustion from the collapse of a building. Again I suggest this is not only irrelevant but also an unsubstantiated and misleading theory.

To where is the kinetic energy of the falling beam going to be applied?

I suggest the kenetic energy will be spread thoughout the 400,000 or so tons of material and therefore will be insignificant in creating hot spots as you have theorised.

Perhaps you can show some more relevant examples which show this theory as a possibility.

Also your theory appears to be at odds with NIST's findings. Can you paste text from NIST which states that kinetic energy caused extremely high temperatures and melted steel?


You state:

You have showed me buckled columns that only fell so far because they were still attached to an unbuckled structure

You previously stated at: https://www.metabunk.org/posts/42412

A vertical slender column which buckles IS collapsing. The only thing to follow it is its meeting ground zero.

Do you accept this is misleading and incorrect with both regard to columns and transverse beams?

 

[Cairenn]

The entire WTC complex was ordered to evacuated after the first plane hit.

8:59 a.m.-9:02 a.m. September 11, 2001: Orders Given to Evacuate WTC Buildings, But Not Heard by Fire Safety Director
Edit event

At 8:59 a.m., the Port Authority Police Department (PAPD) commanding officer of the World Trade Center complex calls for the evacuation of the North Tower and the South Tower, saying, "As soon as we're able, I want to start a building evacuation, building one and building two, till we find out what caused this." Thirty seconds later, the officer repeats his order, but this time calls for all the buildings in the WTC complex to be evacuated. At 9:02, he repeats this, saying, "Evacuate all buildings in the complex. You copy? All buildings in the complex." However, his order is given over WTC police radio channel W, which cannot be heard by the deputy fire safety director in the South Tower. [Bergen Record, 8/29/2003; 9/11 Commission, 7/24/2004, pp. 293; National Institute of Standards and Technology, 9/2005, pp. 28, 32, 200-202]

Entity Tags: World Trade Center

Timeline Tags: Complete 911 Timeline, 9/11 Timeline
AddThis
(9:03 a.m.) September 11, 2001: WTC Building 7 Evacuated
Edit event

According to a soldier at the scene, WTC Building 7 is evacuated before the second tower is hit. [Fort Detrick Standard, 10/18/2001] The National Institute of Standards and Technology (NIST) states, "As the second aircraft struck WTC 2, a decision was made to evacuate WTC 7." This would be just after the Port Authority Police Department called for the evacuation of the entire WTC complex (see 8:59 a.m.-9:02 a.m. September 11, 2001). But by this time, "many WTC 7 occupants [have] already left the building and others [have] begun a self-evacuation of the building." [National Institute of Standards and Technology, 9/2005, pp. 109] All individuals in the Secret Service's New York field office, located in WTC 7, were ordered to evacuate after the first attack, and they are in the process of doing so when the second plane hits the South Tower.

...

(9:04 a.m.) September 11, 2001: WTC 7 Alarms Activate; OEM Calls for Air Security and Warned of Plane Heading for New York
Edit event

The second plane hitting the World Trade Center (see 9:03 a.m. September 11, 2001) causes internal alarms to go off in WTC Building 7, located just a few hundred feet away from the Twin Towers. The alarms warn there is no water pressure and that the building's emergency power generator has been activated. Office of Emergency Management (OEM) staff, based in Building 7, immediately request air security over New York. They are told that federal support is on its way, but the Federal Aviation Administration instructs them to use NYPD and Port Authority Police Department air assets to clear the airspace around the WTC. They are also warned that the Kennedy Airport control tower is reporting an unaccounted for plane heading towards New York. A report by the Mineta Transportation Institute will claim that this plane is Flight 93, which later crashes in Pennsylvania. [Jenkins and Edwards-Winslow, 9/2003, pp. 16] However, Flight 93 is still flying west at this time, and only reverses course and heads towards Washington at around 9:36 a.m. (see (9:36 a.m.) September 11, 2001). According to at least one person at the scene, WTC 7 is evacuated around this time due to the reports of this incoming third plane (see (9:03 a.m.) September 11, 2001). [Jems And FireRescue Supplement, 3/2002, pp. 68 pdf file]

Entity Tags: Office of Emergency Management, World Trade Center, Federal Aviation Administration

Timeline Tags: Complete 911 Timeline, 9/11 Timeline
(9:30 a.m.) September 11, 2001: Office of Emergency Management Command Center Is Evacuated; Exact Time Is Unclear
Edit event

Thomas Von Essen.Thomas Von Essen. [Source: Publicity photo]The headquarters of New York's Office of Emergency Management (OEM), which is on the 23rd floor of WTC Building 7, is evacuated at approximately 9:30 a.m., according to the 9/11 Commission. The headquarters was opened in 1999 and was specifically intended to coordinate the city's response to disasters such as terrorist attacks (see June 8, 1999). A senior OEM official orders the evacuation after being told by a Secret Service agent that additional commercial planes are unaccounted for (see (9:30 a.m.) September 11, 2001). [9/11 Commission, 7/24/2004, pp. 283-284 and 305] OEM personnel do not initially respond to the evacuation order with a sense of urgency. According to a 2003 report by the Mineta Transportation Institute, "They calmly collected personal belongings and began removing OEM records, but they were urged to abandon everything and leave the building quickly." [Jenkins and Edwards-Winslow, 9/2003, pp. 16] However, there are contradictory accounts of when the OEM command center is evacuated. The National Institute of Standards of Technology (NIST) claims the evacuation happens slightly later than stated by the 9/11 Commission, at "approximately 9:44 a.m." [National Institute of Standards and Technology, 9/2005, pp. 109] Other accounts suggest it may have happened before 9:03, when the second attack occurred (see (Soon After 8:46 a.m.-9:35 a.m.) September 11, 2001 and (Shortly Before 9:03 a.m.) September 11, 2001). Fire Commissioner Thomas Von Essen will arrive at WTC 7 shortly before the collapse of the South Tower, looking for Mayor Giuliani. Learning that the OEM headquarters has been evacuated, he later claims that he thinks, "How ridiculous. We've got a thirteen-million-dollar command center and we can't even use it." [Essen, 2002, pp. 26] He says in frustration, "How can we be evacuating OEM? We really need it now." He will later tell an interviewer that he'd headed for the OEM headquarters because, "I thought that was where we should all be because that's what [it] was built for." [Fink and Mathias, 2002, pp. 230] All civilians were evacuated from WTC 7 earlier on, around the time the second WTC tower was hit (see (9:03 a.m.) September 11, 2001).

(Shortly After 9:59 a.m.-12:10 p.m.) September 11, 2001: Security Officer Heads into WTC 7 and Gets Trapped in Building
Edit event

A security officer for one of the businesses in Building 7 of the World Trade Center (WTC 7) goes up WTC 7 and subsequently becomes trapped on its seventh floor. [National Institute of Standards and Technology, 9/2005, pp. 109-110; National Institute of Standards and Technology, 11/2008, pp. 298-299 pdf file] Although most people were evacuated from the building around the time the South Tower was hit, if not earlier (see (9:03 a.m.) September 11, 2001), after the South Tower collapses at 9:59 a.m. the security officer heads up to a floor in the 40s in WTC 7, reportedly to check that all his personnel have left. (The name of the company he works for is unstated.) He is initially accompanied by a police officer, but at around the 10th floor this officer has difficulty breathing, and so goes back down and exits the building. When the North Tower collapses at 10:28 a.m., WTC 7 shakes and the stairwell goes dark. The security officer, who has reached the 30th floor by this time, heads back down the stairs. When he reaches the 23rd floor, where the headquarters of New York's Office of Emergency Management (OEM) is located, he opens the door to check for any members of staff that might still be there, but finds the area filled with smoke. (The OEM was evacuated at about 9:30 a.m., if not earlier (see (Soon After 8:46 a.m.-9:35 a.m.) September 11, 2001 and (9:30 a.m.) September 11, 2001).) He then continues down to the seventh floor, where he has to stop because he is unable to see or breathe. He is able to break a window, and calls for help. [National Institute of Standards and Technology, 11/2008, pp. 298-299 pdf file] At around 12:10 to 12:15 p.m., firefighters will enter the building and rescue the security officer, escorting him down the stairs and out of the building. They will also rescue two men who are trapped on the eighth floor (see 12:10 p.m.-12:15 p.m. September 11, 2001). [National Institute of Standards and Technology, 6/2004 pdf file; National Institute of Standa




Among these individuals are Barry Jennings, a City Housing Authority worker, and Michael Hess, New York's chief lawyer who is also a longtime friend of Mayor Rudolph Giuliani. The two had gone up to the 23rd floor emergency command center of the Mayor's Office of Emergency Management after the first attack occurred, but found it empty (see (Shortly Before 9:03 a.m.) September 11, 2001). [New York Times, 11/21/1997; Associated Press, 9/11/2001; Giuliani, 2002, pp. 20-21 and 244; Dylan Avery, 2007] They then headed downstairs but became trapped around the eighth floor by smoke and debris that filled the staircase. After breaking a window and calling for help, they were spotted by firefighters outside. When the firefighters go in, they also find a security officer for one of the businesses based in the building, who is trapped on the seventh floor by the smoke in the stairway. This officer headed up the building after the South Tower collapsed at 9:59, to check that all his personnel had left there (see (Shortly After 9:59 a.m.-12:10 p.m.) September 11, 2001). All three men are escorted out of the building.

http://www.historycommons.org/context.jsp?item=a903

 

[RolandD]

Yes, it is annealed in order to render it workable from its hardened state after being worked before!



No, but you used it an excuse for what you did say. And annealing was never possible in wtc7 - obviously.



If so, why this?



The whole point of annealing is that it is the process which renders steel workable and usable, and it's deliberate - otherwise your piece wouldn't be fit to work with - the final process a structural steel goes through after fabrication (bending, rolling - all that) is annealing - it's a bit like healing, really - restoring it to its original ductility in order to make the thing viable. There are degrees of heat treatment (annealing) depending on the qualities you want from your steel.





Promise?

Lee, let me qualify what we said. Cairenn and I both have a great deal of experience in working with non-ferrous metals and not just a little experience in ferrous metals. Unfortunately, the term annealing is used in different ways for non-ferrous and ferrous metals, and we were using it in a way we were more familiar with, and using it incorrectly as you have pointed out. But, even though we were using the term incorrectly, the action of heat on steel causing it to lose strength even after it has cooled is correct.

When heated enough and allowed to cool, steel will lose all tempering and become weak and more malleable. When heated and quenched, it can become brittle or tempered depending on the liquid used.

As for attempting to be polite, I believe your only intention on this board is to cause trouble and chaos and I see no reason to be civil to you.

 

[Mick West]

I agree with this statement but the fact is certain people seem unable to do this and insist on making personal attacks in a gaslighting fashion, thereby subverting and disrupting the topic. I think Grieves has hit on a very important reason for this and unless it is addressed, it appears the attacks and disruption will continue. I appreciate the difficulty but do you have any practical suggestions for preventing the attacks as the root cause appears deep seated and unabated despite appeals to desist.

Appeals, infractions, bans. These are all cooling rods, not cures.

Everyone could contribute by ignoring such attacks, and discussing on actual evidence and science.

 

[Jazzy]

The claim: If the steel got hot enough to become soft and deformable then it stayed that way. That is completely incorrect.

Well, then argue with your external source. In time sequence.

Steel Evaluations
Steel is a bit less straightforward to analyze after a fire. If steel is exposed to temperatures of approximately 1200°F, metallurgical changes can occur.

COLLAPSE.

The changes are usually only temporary and once the steel cools, it can regain nearly 100% of its pre-fire strength. Although the steel may have regained most of its pre-fire strength, it may have been distorted or dimensionally changed by the fire.

Clearly, the temperatures and controls inside building 7 don't relate either to the process of annealing

Of course they do. FIRE relates to TEMPERATURE and so does ANNEALING. You can pick the journey of the WTC steel through this diagram. Seven hours is 25,000 seconds.



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

nor to the false claim that once steel is heated to the point of being 'soft and deformable', it remains that way. Beware: chop-logic at work.

The collapse was the finish of the heating process at WTC7, so whether it retained its cold strength in the street debris is moot, and certainly irrelevant.

I have the same message on my pouch of Virginia tobacco, warning me of its contents.

 

[Jazzy]

it is demonstrating transfer of energy through motion.

Contact.

Yes a totally different concept

Contact.

but as you admit, there is not one example of vast amounts of heat from the collapse of a building.

I have just demonstrated to you the energy available at the collapse. That potential energy was capable of raising to melt 1,270 tons of steel. All kinetic energy results in heat, because heat IS a form of kinetic energy. The manner of this change is a process you would do well to understand.

What proportion of the total energy resulted in hotspots is open to question. I would guess around 10%, making the likelihood of 127 tons of seriously hot steel to be found right at the bottom in random places (because large sections were seen to detach), but also around the columns where they received floor shear loads. The tangled and flattened heap of columns and beams, flattest and hottest against its base, was capped over by progressively more insulating rubble.

These hot dry states, surrounded by insulation, could persist for weeks, as they did. They were hotboxes, of sorts. So the infra-red imagery is entirely to be expected.

Again I suggest this is not only irrelevant but also an unsubstantiated and misleading theory.

Wherever you were schooled, you should go and demand your money back.

Energy occurs in many forms, including chemical energy, thermal energy, electromagnetic radiation, gravitational energy, electric energy, elastic energy, nuclear energy, and rest energy. These can be categorized in two main classes: potential energy and kinetic energy.

Kinetic energy may be best understood by examples that demonstrate how it is transformed to and from other forms of energy. For example, a cyclist uses chemical energy provided by food to accelerate a bicycle to a chosen speed. On a level surface, this speed can be maintained without further work, except to overcome air resistance and friction. The chemical energy has been converted into kinetic energy, the energy of motion, but the process is not completely efficient and produces heat within the cyclist.

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

Also your theory appears to be at odds with NIST's findings.

How could it be? The NIST Report concerned itself with events preceding collapse. We are discussing events following collapse.

Can you paste text from NIST which states that kinetic energy caused extremely high temperatures and melted steel?

I will ignore that.

You previously stated "A vertical slender column which buckles IS collapsing. The only thing to follow it is its meeting ground zero". Do you accept this is misleading and incorrect with both regard to columns and transverse beams?

I also offered you the sources for that. Have you read them?

and/or instantaneous combustion

Getouttahere.

Oxymoron, you are once more attacking my credibility rather than following the truth. If you do not understand what I present it really would be better to come back with a question which I might be more able to answer without showing up your ignorance.

But first you must acknowledge and read the sources I present.

 

[Oxymoron]

Balls

Contact.

Motion and contact. Non mutually volatile objects, (such as steel balls), of the same temperature, which are in contact but at rest, do not result in a change of temperature unless from an outside source. So no it is not simply 'contact' as you errantly state. Further, the video in question does not even remotely or indirectly refer to heat... it is all about motion. If it was to be of any relevance whatsoever to this discussion, it should be dealing quantitatively with how much and at what rate the balls increased in temperature.

Rubble/steel

Contact.

See above and add 'rubble'.

I have just demonstrated to you the energy available at the collapse. That potential energy was capable of raising to melt 1,270 tons of steel.

It is also capable of many other things like bending columns and beams and pulverizing reinforced concrete

All kinetic energy results in heat, because heat IS a form of kinetic energy.

The implication is patently misleading, therefore untrue because it misleadingly, (to those who are not knowledgeable about such things), suggests heat is the major, (or even sole), product when in fact it is a small by product of the work. If all kinetic energy resulted in heat there would be no energy left for work, such as bending, pulverizing and ejecting.

The manner of this change is a process you would do well to understand.

This is the type of patronizing comment you would do well to omit as it is inciting and against the politeness policy which is a big issue at the moment, and the type of comment you have been repeatedly asked to desist from.

What proportion of the total energy resulted in hotspots is open to question.

Very much so. In fact it is pure conjecture on your part.

I would guess around 10%, making the likelihood of 127 tons of hot steel to be found right at the bottom in random places, but also around the columns where they received floor shear loads, capped over by insulating rubble, dry at first, but getting wetter as fireman's water percolated down.

As you state... a guess.

The infra-red imagery is entirely to be expected.

Is it? And yet it is unique in it's intensity and duration in such an event.

Wherever you were schooled, you should go and demand your money back.

This is the type of patronizing comment you would do well to omit as it is against the politeness policy which is a big issue at the moment, and the type of comment you have been repeatedly asked to desist from.

Energy occurs in many forms, including chemical energy, thermal energy, electromagnetic radiation, gravitational energy, electric energy, elastic energy, nuclear energy, and rest energy. These can be categorized in two main classes: potential energy and kinetic energy.

Kinetic energy may be best understood by examples that demonstrate how it is transformed to and from other forms of energy. For example, a cyclist uses chemical energy provided by food to accelerate a bicycle to a chosen speed. On a level surface, this speed can be maintained without further work, except to overcome air resistance and friction. The chemical energy has been converted into kinetic energy, the energy of motion, but the process is not completely efficient and produces heat within the cyclist.

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

Yes, any work produces a relatively small amount of heat but at a very small ratio, because the workprocess is not completely efficient. If this were not the case, every time I repeatedly hammered a nail, it would melt.

How could it be? The NIST Report concerned itself with events preceding collapse. We are discussing events following collapse.

Did NIST not investigate where the molten metal came from?

I also offered you the sources for that. Have you read them?

I have either found your sources to be irrelevant/misleading, (like the video in question), or very often not working, (error 404's)

Oxymoron, you are once more attacking my credibility rather than following the truth.

I am attacking the credibility and veracity of your arguments... I suggest it is you who perceives it as personal.

If you do not understand what I present it really would be better to come back with a question which I might be more able to answer without showing up your ignorance.

You have never done so.

But first you must acknowledge and read the sources I present.

I have either found your sources to be irrelevant or very often not working, (error 404's)

I note you avoided the question as to whether you still stick by your statement, "A vertical slender column which buckles IS collapsing. The only thing to follow it is its meeting ground zero."

I would also add that 7's vertical columns were far from slender, so again that statement appears deceptive, (in that you are conflating slender beam construction, (which is a relative term anyway)), as well as being evidentially untrue.

 

[lee h oswald]

The claim - once steel is heated to a point it is soft and deformable then it remains that way after cooling

Originally Posted by Pete Tar

Wouldn't a thick piece of steel that got hot enough to soften retain that property for a while (ie, several hours)? Seems fair.

Post 164:

No.

Post 165: Me:

Imagine a fifteen year old has some homework on what happens to structural steel after it's been heated and cooled. She Googles her question and up pops your one paragraph, unequivocal statement of fact: "If the steel got to the softening temperature, then it stayed soft and deformable". And said fifteen year old, happy in her new-found knowledge, goes with that. What mark do you think she might get?

Jazzy:

Full marks

Just a slight contradiction (and in short order). Don't you ever get tired of just making things up?

 

[lee h oswald]

Moderator Join DateMay 2012LocationPlanet EarthPosts327Thanks68Thanked 75 Times in 54 Posts
[h=2]You have received an infraction at Metabunk.org[/h]

Dear lee h oswald,

You have received an infraction at Metabunk.org.

Reason: A bit impolite
-------
Mocking isn't necessary, Lee.
-------

This infraction is worth 1 point(s) and may result in restricted access until it expires. Serious infractions will never expire.

Original Post:
https://www.metabunk.org/showthread.php?p=44162
The claim - once steel is heated to a point it is soft and deformable then it remains that way after cooling

Originally Posted by Pete Tar

Wouldn't a thick piece of steel that got hot enough to soften retain that property for a while (ie, several hours)? Seems fair.



Post 164:

Originally Posted by Jazzy
No.




Post 165: Me:
Imagine a fifteen year old has some homework on what happens to structural steel after it's been heated and cooled. She Googles her question and up pops your one paragraph, unequivocal statement of fact: "If the steel got to the softening temperature, then it stayed soft and deformable". And said fifteen year old, happy in her new-found knowledge, goes with that. What mark do you think she might get?



Jazzy:

Full marks


Just a slight contradiction (and in short order). Don't you ever get tired of just making things up?


All the best,
Metabunk.org​

The one character aspect I am most proud of is being able to recognize that something can be a total load of crap.
​

This is beyond daft. 'A bit impolite'? Can we see the scale? I can't see anything close to even-handedness here. Apparatchiks a go-go. Absurd

 

[Mick West]

This is beyond daft. 'A bit impolite'? Can we see the scale? I can't see anything close to even-handedness here. Apparatchiks a go-go. Absurd

If you would just directly address the point then maybe there would be fewer problems. What does science say about the topic?

 

[Oxymoron]

The energy isn't a conjecture. I have demonstrated it mathematically. The proportion of this non-conjecture isn't a conjecture. There must be one. The question is a conjecture, because that's what a conjecture is. A question.
The sentence as a whole isn't a conjecture. It's a statement of FACT.
But one educated by years of experience following years of training.

Your definition appears at odds with the dictionary's definition.

http://dictionary.reference.com/browse/conjecture

[h=2]con·jec·ture[/h] [kuh

n-jek-cher] Show IPA noun, verb, con·jec·tured, con·jec·tur·ing.

noun 1.the formation or expression of an opinion or theory without sufficient evidence for proof.

2.an opinion or theory so formed or expressed; guess; speculation.

3.Obsolete . the interpretation of signs or omens.

I agree with you, it's just as unique as collapsing long-span beamed steel-framed skyscrapers are.

Incomparable to any other event on then?

No. You have been sold a pup if you believe you know anything about physics and engineering.

Seems a bit impolite to me

(After Oxymoron reads what WIKI writes about kinetic energy)
By which you mean to say? I'll answer what I think you mean.

Essentially yes. That is all anyone can do is it not?

Significantly less work is done destroying brittle material than bending tough material.

Agreed

Significantly less work is done at the top of the pile than at the bottom of it.

Perhaps you would clarify what you mean.

The work, however, is there to be done. And that which doesn't go to bursting or bending goes to heating. We have established that.
And I gave you a ratio to consider: ten per cent.

Which is conjecture? I don't mind, so long as we know how much weight to give it. But ok, let us accept that as reasonable

I thought they investigated up to the collapse. What molten metal? Do you have pictures or videos of it? Where was it?

I believe there is a thread on this.

Physics is irrelevant? Maybe to a truther of some sort, but the rest of us rather respect it.

Again, seems a bit impolite and a parody of what I said.

Yet you have never told me this up to this point. It doesn't point to your competence, does it?

Again, seems a bit impolite and a transfer of responsibility.

I have pointed out logical flaws in a number of links in your posts and disputed the relevancy of the links. If some do not work and I have had to examine irrelevant links, I suggest it is reasonable not to be overly concerned about the ones which do not work. I tend to cut and paste as much of the relevant parts as possible and back it up with a link.

 

[Jazzy]

This is beyond daft. 'A bit impolite'? Can we see the scale? I can't see anything close to even-handedness here. Apparatchiks a go-go. Absurd

I'll get around to you in a moment.

 

[Jazzy]

Your definition appears at odds with the dictionary's definition.

My question was a matter of fact. I showed you how.

Incomparable to any other event on then?

Yes.

Seems a bit impolite to me

When I'm forced to repeat myself I begin to remove emollients.

Essentially yes. That is all anyone can do is it not?

It's important to pick exact terms in order to construct an accurate concept.

Agreed

Allows me a small expression of relief.

Perhaps you would clarify what you mean.

The last pieces to land on the pile have been detached from the closest parts of the crumbling tower and therefore haven't fallen very far. They will be much more massive than their equivalent pieces falling from a thousand feet higher, but the kinetic energy they contain is proportional to the square of their speed - so if traveling half as fast they will only possess a quarter of the kinetic energy plus a bit. The square rule rules.

The other way of looking at it is that the potential energy equation works for elements of the tower just as it does for the tower as a whole. PE = 0.5*M*g*h. The square function is within g, of course, with h the variable.

Which is conjecture? I don't mind, so long as we know how much weight to give it. But ok, let us accept that as reasonable.

It is a fact that there is a question. That isn't a conjecture.

I believe there is a thread on this.

It was a straw with insufficient buoyancy.

Again, seems a bit impolite and a parody of what I said.

It wasn't something you recognized as physics.

Again, seems a bit impolite and a transfer of responsibility.

There are several reasons why links don't get found. I check them when I make them. If they don't work for you, you have to tell me, for I am not possessed of psychic powers. Links that are not taken up soon may often atrophy. The responsibility could only be yours. (In the case of my blog, ouch!)

I have pointed out logical flaws in a number of links in your posts and disputed the relevancy of the links. If some do not work and I have had to examine irrelevant links, I suggest it is reasonable not to be overly concerned about the ones which do not work. I tend to cut and paste as much of the relevant parts as possible and back it up with a link.

That won't wash. You aren't being serious. I know when I'm having a sensible discussion. I've been discussing things sensibly with people for a half century at least.

 

[Jazzy]

The claim "once steel is heated to a point it is soft and deformable then it remains that way after cooling".

Wouldn't a thick piece of steel that got hot enough to soften retain that property for a while (ie, several hours)? Seems fair.

No

Just a slight contradiction (and in short order). Don't you ever get tired of just making things up?

A thick piece of steel (that is a piece with a high volume/surface area ratio) that got hot enough to soften, would if left alone end up permanently softened because its mass/surface area ratio would prevent rapid heat loss, and it would anneal itself. It wouldn't retain its softness "for a few hours", but permanently*.

If on the other hand it is dropped instantly into quenching water it would end up pretty hard on the outside, pretty tough within.

If a thin piece of steel (that is a piece with a low volume/surface area ratio) that got hot enough to soften, is dropped instantly into quenching water it would end up totally hard on the outside, pretty hard within.

It's a matter of the rate at which the temperature falls.

There are further properties which tend to go unnoticed. The austenitic process actually begins at a lower temperature than 800 deg C but proceeds very slowly. 450 deg C? Not sure.

When the steel is subject to tension, compression, or torsion, this slow breakdown and realignment of steel's crystalline structure manifests itself in the process known as CREEP, and is responsible for the load-shifting, through the towers' top hat trusses, between the interior and exterior columns, which helped bring on their collapses.

What does it matter, in this instance, whether the steel regained its hardness or not? If it softened sufficiently, and crept, then it certainly approached its point of buckling instability over time. When two floors, one above the other, detached, there was no way the newly-detached columns could stand, as their stability dropped to a ninth of their former value.

So you're arguing over the hardness of the wreckage? Spare us all from any more of that.

* There is a very small amount of hysteresis in cold grain re-structuring which makes my "No" only partially correct, it is true, but it hardly compares with your bullying of Cairenn and somewhat successful campaign to deflect the direction of the thread from: WTC7: Did the fires burn long and hot enough? to "everyone that argues with me is incompetent and doesn't know what they're talking about".

 

[MikeC]

When I was an apprentice I had a job with a couple of others of "disassembling" a RR Dart engine from a F-27 Friendship that had crashed into Manukau Harbour, west of Auckland (2 ppl killed, 2 survived) in 1979 (1979 was a bad year for NZ aviation - the Erebus crash was also in 1979 - 257 dead!)

The engine was heavily corroded due to salt water, and we used cold chisels a lot for knocking off nuts and splitting casings apart. Eventually they got blunt, so we sharpened them on grind stones....but then the broad heads eventually wore down, so we heated them red hot and hammered the end flat to make it wide again, then heated them again and quenched them to harden them.

And then the 1st time we used one on something hard the whole end shattered!

We quickly checked those that had not been used, and there was a web of cracking across them - the rapid quenching had over stressed them that much. So they got reheated red hot, hammered flat again and cooled in oil. THEN we "blued" them - heated them until the end changed colour to a lovely deep blue, and again quenched in oil to temper them.

We actually did a lot of "blueing" like this as apprentices - mostly on various tools and exercises we had made ourselves in practical classes.

In a random situation like WTC7 where you cannot say anythnig for certain beyond "some of it was hot (and perhaps some degree (sic) of knowledge of how hot) and some of it was cold" it seems quite difficult to support any firm conclusions on teh performance of the steel that require any more precision than that!

 

[Cairenn]

That was my whole point. The steel was heated and it's strength could have been altered by that.