WTC 1 & 2. What happened after collapse initiation?

[~enigma~]

I missed all events of the alleged collapse initiation; buckling of columns, free fall of masses, impact(s), transfer(s) of released energy to the structures (above and below of course). Can't see them on any videos! To me, they are fantasy. Inventions.
So pls provide links to evidence of these, in my eyes, fantasy events. I am curious to know:
1. What was the original length of the columns that buckled?
2. How/where/when did they buckle?
3. Why would this buckling cause free fall?
4. What exactly free fell, when and where. Start and end times, pls of various weights.
5. What impacted what after free fall, when and where? (Pls, don't tell me the whole upper block impacted the whole structure below. I am only curious of what structural lowermost parts of the upper block made contact with what uppermost structural parts below. You need only to show a few examples).
6. Explain then the transfer of energy in one of the examples of 5 and what happens to the two structural parts in contact.
If you can explain 6, then
7. explain why the energy transfer there would cause destruction of the whole tower as witnessed on TV.

Ah....so 1 question that gets answered leads you to ask more...well instead of reinventing the wheel, I will just point you here since you obviously have not read it...

http://wtc.nist.gov/

ETA - But you asked what happened after collapse initiation and I told you that the wtc came crashing down. What exactly is your problem understanding that? Please stop the charade that you are smart.

 

[Profanz]

No, the upper portion did not stay intact as it plowed through the lower portion of the towers. Remember tanabear, the towers were not solid. They were held together by nuts, bolts, welds, etc. When these were subjected to such incredible amounts of force, there was not chance of them holding.

Remember the upper block wasn't made of anything more substantial then the much larger lower part it is claimed to have crushed. The upper block that was supposedly subjected to much structural damage and a raging inferno before it fell and crushed the fully intact not on fire much larger lower portion.

 

[Pardalis]

I've always felt the propagation of the collapse was fairly obvious if you watched the copious number of videos.

After initiation the downward movement of the upper mass fell upon intact floors below and caused structural disintegration of these floors into the three basic component systems of the tower. Each of these three component systems behaved differently, and both video and the spread of debris after collapse confirms what happened:

EXTERIOR COLUMNS
The exterior columns were constructed in segments consisting of three columns, three stories high, connected by two spandrel plates. As such the exterior is best thought of not as a series of columns, but as a brickwork pattern of panels. Upon collapse initiation the collapse forces caused failure of the connections to the floor trusses, and these panels were forced outwards in chunks that broke away from the buildings. The size of these chunks varied - while single panels broke away there were also massive sections dozens of floors high and many panels wide that fell away intact and only then began to break up.

We can confirm this from videos, and also from the debris pattern. Most of the exterior panels were located in a fan pattern away from the building, with the upper most ones furthest away. It was almost exclusively the exterior panels which caused the severe damage to surrounding buildings.

FLOOR TRUSSES
With the exterior columns peeling away from the structure in great chunks, this left the light weight floor trusses very vulnerable and trying to absorb virtually the entire gravity load of the upper collapsing structure. These floor trusses were now only held up by their connections to the core of the structure, and under the loads they faced, these connections easily failed. This left the floor trusses to fall downwards onto lower trusses, causing a pancake type phenomenon as they crashed down on each other. If you think of them like square donuts stacked up on a central spike (the core) it gives you an idea of the mechanics of their failure.

There is some evidence that the floor truss collapse, requiring little force (only core connections needed to be broken) and being self-propagating (each failed truss would immediately join the mass falling on the truss below it) accelerated ahead of the visible collapse front, which would have further exacerbated the exterior column "peel away".

The fate of the floor trusses can be confirmed by eye witness testimony, and from the debris fields - most of the denser floor contents and truss material was located in close proximity to the building footprints, and the trusses themselves were found (according to NIST) stacked on top of each other in a heap at the base of each tower.

That leaves only our third component system:

BUILDING CORE
With the floor trusses and exterior columns breaking away that left only the core columns - the strongest part of the structure and also the component absorbing the least of the impact force (the strength of the core columns would have likely resulted in collapse material initially breaking either side of the core columns, much like a rock in a stream, thus protecting the core from much of the collapse force). And indeed, the core columns did in fact remain standing - for a time.

Of course simple physics will tell you that the cores alone - especially after the battering of the collapse - simply could not remain standing for any length of time. Tall thin structures are far too unsteady - which is why radio towers are stabilised with cables.

And so, the core structure failed at its weakest points which were the bolts and welds holding each three-storey section together.

The fate of the core columns is confirmed by video of the collapses which clearly shows the core of each tower still standing after the exterior columns and trusses had collapsed. It is further confirmed by the debris field - core columns were located in a scatter pattern around the building footprint, on the very top of the pile indicating they had fallen after everything else.

So there you have it. In simple terms, it went like this:

1. Collapse initiation
2. Exterior panels break away from truss assemblies
3. Truss assemblies break away from core structure
4. Core structure fails

Great post gumboot, but unfortunately...

I hope that helped.

Remember the upper block wasn't made of anything more substantial then the much larger lower part it is claimed to have crushed. The upper block that was supposedly subjected to much structural damage and a raging inferno before it fell and crushed the fully intact not on fire much larger lower portion.

Apparently not. Some people are incapable of learning.

 

[Myriad]

Remember the upper block wasn't made of anything more substantial then the much larger lower part it is claimed to have crushed. The upper block that was supposedly subjected to much structural damage and a raging inferno before it fell and crushed the fully intact not on fire much larger lower portion.

Profanz, I've been discussing with Sizzler the physical explanation for unequal crushing of the upper and lower blocks as the progressive collapse proceeds, on this thread. (You can start on page 2, which is where this link should take you.) If you're interested in this topic, please read it and then join in.

Respectfully,
Myriad

 

[Heiwa]

Ah....so 1 question that gets answered leads you to ask more...well instead of reinventing the wheel, I will just point you here since you obviously have not read it...

http://wtc.nist.gov/

ETA - But you asked what happened after collapse initiation and I told you that the wtc came crashing down. What exactly is your problem understanding that? Please stop the charade that you are smart.

Thanks for the advice. The Nist.gov report unfortuntaley stops just prior initiation and does not clarify the following events prior impact (and destruction that follows). These events between start of initition and impact require about 0.8 seconds so they should have been picked up by cameras and other equipment ... but they are not. There is no evidence for them.

In my opinion, they never occured, they are fantasy ... and there we are. Conspiracy theories are always based on fantasy. 911 is the worst one I have encountered.

 

[~enigma~]

Thanks for the advice. The Nist.gov report unfortuntaley stops just prior initiation and does not clarify the following events prior impact (and destruction that follows). These events between start of initition and impact require about 0.8 seconds so they should have been picked up by cameras and other equipment ... but they are not. There is no evidence for them.

In my opinion, they never occured, they are fantasy ... and there we are. Conspiracy theories are always based on fantasy. 911 is the worst one I have encountered.

Oh so you base your inside job bs on opinion and not on evidence...Thanks, you are the first truther to EVER admit that. BTW initiation occurred is how those words are spelled

 

[BenBurch]

Thanks for the advice. The Nist.gov report unfortuntaley stops just prior initiation and does not clarify the following events prior impact (and destruction that follows). These events between start of initition and impact require about 0.8 seconds so they should have been picked up by cameras and other equipment ... but they are not. There is no evidence for them.

In my opinion, they never occured, they are fantasy ... and there we are. Conspiracy theories are always based on fantasy. 911 is the worst one I have encountered.

No, son, they stop right AFTER initiation. Right at the time when the columns buckle. After that, there is nothing whatsoever supporting the top of the building and the results are obvious except to idiots.

 

[applecorped]

Thanks for the advice. The Nist.gov report unfortuntaley stops just prior initiation and does not clarify the following events prior impact (and destruction that follows). These events between start of initition and impact require about 0.8 seconds so they should have been picked up by cameras and other equipment ... but they are not. There is no evidence for them.

In my opinion, they never occured, they are fantasy ... and there we are. Conspiracy theories are always based on fantasy. 911 is the worst one I have encountered.

Thanks for clearing that up.

 

[chillzero]

Heiwa, perhaps you could answer post 10 for me?

 

[eeyore1954]

Remember the upper block wasn't made of anything more substantial then the much larger lower part it is claimed to have crushed. The upper block that was supposedly subjected to much structural damage and a raging inferno before it fell and crushed the fully intact not on fire much larger lower portion.

What does this mean? Do you think because it was damaged and burning it would be unable to crush the lower portion. Why?

 

[Jonnyclueless]

WTC 1 & 2. What happened after collapse initiation?

Collapse continuation.

Fixed.

 

[jhunter1163]

Since Heiwa is fond of food analogies, when I was four years old I learned that when the weight of the pile of macaroni and cheese on your paper plate exceeds the paper plate's load capacity, collapse ensues. This principle is applicable to both paper plates and damaged World Trade Center towers.

When load > load capacity, collapse is inevitable.

 

[johnny karate]

tanabear, if you can show, using scientifically correct calculations (as approved by REAL Physicists or Engineers) that the collapse, once initiated, was not unstoppable, then you might have a talking point. Otherwise, discussion on this topic is useless.

Bump for the Truthers waxing intellectual in this thread.

 

[tanabear]

What part of the collapses don't you understand?

Well, here is an issue that I haven't heard explained yet. How did the upper block become separated from the lower block when the vast majority of the perimeter and core columns were still intact after the plane impact?

Can I just ask... why would they? Why is it relevant to anything?

It is after collapse initiation when most of the people in the towers were killed. NIST was tasked with explaining how and why the buildings were destroyed. They have yet to fulfill their obligations.

With regards to pancaking. The problem is that Steven Jones and many of the truthers have a hard time understanding that, with regards to INITATION, pancaking was not the cause, however during the collapse there was pancaking.

Of course, pancaking is not the cause. The cause of a pancake collapse is considered to be truss failure. Shyam Sunder made those statements to Popular Mechanics when the pancake collapse explanation was widely accepted. Later they discarded this idea. As Shyam Sunder later stated they saw no evidence of pancaking in any of the videos or photographs that they have. In other words, the official explanation changed. Brent Blanchard has even stated that the floors were not pancaking.

tanabear, if you can show, using scientifically correct calculations (as approved by REAL Physicists or Engineers) that the collapse, once initiated, was not unstoppable, then you might have a talking point. Otherwise, discussion on this topic is useless.

TAM

Where are NIST's calculations showing that once the collapse initiated it was inevitable? Why should NIST get away with making a statement without having to prove it?

 

[T.A.M.]

Where are NIST's calculations showing that once the collapse initiated it was inevitable? Why should NIST get away with making a statement without having to prove it?

Yes, like them providing you with such would convince you.

TAM

 

[applecorped]

Well, here is an issue that I haven't heard explained yet. How did the upper block become separated from the lower block when the vast majority of the perimeter and core columns were still intact after the plane impact?



It is after collapse initiation when most of the people in the towers were killed. NIST was tasked with explaining how and why the buildings were destroyed. They have yet to fulfill their obligations.



Of course, pancaking is not the cause. The cause of a pancake collapse is considered to be truss failure. Shyam Sunder made those statements to Popular Mechanics when the pancake collapse explanation was widely accepted. Later they discarded this idea. As Shyam Sunder later stated they saw no evidence of pancaking in any of the videos or photographs that they have. In other words, the official explanation changed. Brent Blanchard has even stated that the floors were not pancaking.



Where are NIST's calculations showing that once the collapse initiated it was inevitable? Why should NIST get away with making a statement without having to prove it?

Ahem! Et tu troother?

 

[~enigma~]

Where are NIST's calculations showing that once the collapse initiated it was inevitable? Why should NIST get away with making a statement without having to prove it?

Where are any credible calculations showing the WTC was supposed to do this truther run CD...

 

[Myriad]

It is after collapse initiation when most of the people in the towers were killed. NIST was tasked with explaining how and why the buildings were destroyed. They have yet to fulfill their obligations.

When a dam breaks, the investigators' job is to determine why the dam broke. They're not required to explain why after the dam broke, the water rushed downhill and washed away buildings downstream. Even if that's where all of the deaths occurred. Because that's the entirely expected result of a dam breaking.

Progressive collapse is the entirely expected result of collapse initiation. When the building is a straight vertical tower, the entire structure is directly "downstream," so progressive collapse of the entire tower is the expected result.

This is a closer analogy that it might at first appear, actually. In both cases, you have a lot of mass in an elevated position, storing a lot of potential energy, held up by a structure that must stay intact in order to continue doing so. Once it starts moving, anything that's in its path is in trouble.

Respectfully,
Myriad

 

[tanabear]

When a dam breaks, the investigators' job is to determine why the dam broke. They're not required to explain why after the dam broke, the water rushed downhill and washed away buildings downstream. Even if that's where all of the deaths occurred. Because that's the entirely expected result of a dam breaking.

Progressive collapse is the entirely expected result of collapse initiation. When the building is a straight vertical tower, the entire structure is directly "downstream," so progressive collapse of the entire tower is the expected result.

This is a closer analogy that it might at first appear, actually. In both cases, you have a lot of mass in an elevated position, storing a lot of potential energy, held up by a structure that must stay intact in order to continue doing so. Once it starts moving, anything that's in its path is in trouble.

Respectfully,
Myriad

Water running downhill is a something that we all have observed. There is nothing unique about that. A total-progressive collapse of a steel-frame high-rise is not a common event. Which type of collapse initiation are you referring to? Truss failure, column failure or something else. There is more mass beneath the impact zone than above. What causes it to start moving?

You write, "Once it starts moving, anything that's in its path is in trouble."

Apparently not. The upper block was able to plow through the lower block with minimal damage to itself, but then it self-destructs once it hits the rubble pile. Why didn't it continue to plow through the rubble pile?

 

[~enigma~]

What causes it to start moving?

You haven't even studied anything about the collapse and this idiotic "question" makes that clear as a bell.