gravity-driven demolition, question ...

IrelandSpirit · 20-08-2010 11:42am #1

Hiya, I recently came across this short video, which explains (ostensibly) the science behind a gravity-driven demolition. I would seriously appreciate your take on it:

http://www.youtube.com/watch?v=NiHeCjZlkr8&feature=player_embedded

I do realise it is related to the collapse of the Twin Towers, and this is not a CT forum, I'm asking only if the explanation given in the video is scientifically correct. Or at least consistent with Newtonian physics, as claimed.

I also ask the Mods to please respect this line of inquiry; it is purely the science I'm interested in here, NOT conspiracy theories, and the physics forum was recommended as the best place to ask.

Thank you in advance for any help you might provide.

Podman · 20-08-2010 12:54pm

Very interesting video there

FISMA · 20-08-2010 4:47pm

Bad Physics, plain and simple.

A bit better done than the "moon-landing was a hoax" theorists, but still bad Physics.

Videos like this make sense only to those that learn enough science to suit their agenda.

Not only is the science bad, however, the analogy is widely inappropriate. The inherent construction techniques were radically different. Any conclusions drawn between the two are wishful thinking. Not only has the video failed Physics, however, I am sure the Civil Engineers are laughing at well.

Sorry OP, this is just bad science.

IrelandSpirit · 20-08-2010 4:53pm

FISMA wrote: »

Bad Physics, plain and simple.

A bit better done than the "moon-landing was a hoax" theorists, but still bad Physics.

Videos like this make sense only to those that learn enough science to suit their agenda.

Not only is the science bad, however, the analogy is widely inappropriate. The inherent construction techniques were radically different. Any conclusions drawn between the two are wishful thinking. Not only has the video failed Physics, however, I am sure the Civil Engineers are laughing at well.

Sorry OP, this is just bad science.

That's ok, thanks. I'm just interested to know what people well-versed in science have to say. Are you a physicist, btw?

FISMA · 20-08-2010 5:11pm

IrelandSpirit,

The onus is on the person who made this video to abide by the scientific method and release the data, assumptions, calculations et al.

One major flaw is the overly simplistic use of Newton's Laws, which are colloquially used on point particles, not extended bodies like the towers.

I've seen "studies" like this before, mention a pinch of science, show a graph, disallow anyone from seeing your data, and hope that people find it credible.

Did the videographer even take into account the radically different way in which those two structures were designed to bear loads? The videographer has shown a building that has an internal skeletal support system to prove a point about a building with an external skeleton. That is just radically inappropriate IMHO.

Finally, if you tell me what a Physicist is, I will tell you if I am a Physicist.:pac:

IrelandSpirit · 20-08-2010 5:47pm

FISMA wrote: »

IrelandSpirit,

The onus is on the person who made this video to abide by the scientific method and release the data, assumptions, calculations et al.

One major flaw is the overly simplistic use of Newton's Laws, which are colloquially used on point particles, not extended bodies like the towers.

I've seen "studies" like this before, mention a pinch of science, show a graph, disallow anyone from seeing your data, and hope that people find it credible.

Did the videographer even take into account the radically different way in which those two structures were designed to bear loads? The videographer has shown a building that has an internal skeletal support system to prove a point about a building with an external skeleton. That is just radically inappropriate IMHO.

Right, well we don't know, because I suppose the vid's only 4 minutes long, and he does not explain if the internal skeletal support system is even comparable to the WTC. This is perhaps not the best example to provide for a forum like this ...

There is a website where over a thousand architects and engineers (literally) have come together and provided what appears to be strong evidence for controlled demolition, and yes, using the scientific method:

http://www.ae911truth.org/

Should I perhaps choose a video from there? They have several in-depth lectures on the subject, might that be more suitable?

Finally, if you tell me what a Physicist is, I will tell you if I am a Physicist.:pac:

Clever

Edit: the lectures I'm referring do not offer 'conspiracy theories' as regards 'who, or why' etc, only topic appears to be the 'how'

FISMA · 22-08-2010 2:54am

Sorry if the tone appears antagonistic, it is not meant to be.

Have you ever watched those moon landing was a hoax shows, or visited their sites? If that's all you read, they make a pretty good case.

Then you go to a myth-buster type site and they totally pick apart the argument.

Have any of the people, like Jones, spoken in a Public forum and taken questions?

The link you provides cites the following
http://www.bentham-open.org/pages/content.php?TOCPJ/2009/00000002/00000001/7TOCPJ.SGM

Which looks very technical, however, I never heard of them. They seem new on the science block - this study is volume 2 and only a handful of articles. They are cherry picking. Sounds more like self-promotion to me.

Why not go to the well established scientific reviews? Because it does not pass a stink test.

So, they had to use and SEM to find nano-particles? What did they find?

They use the term "Active Thermitic Material." What is that? Sounds like a flux capacitor. It's so nebulous. If they found thermite, they would have stated it, but they did not. Neither are any graphs therein showing thermite.

It's kind of like having trace amounts of ethanol in water and saying that you are drinking rocket fuel.

I find it incredulous that anyone would think a building could survive that collision with a plane, the kinetic energy and momentum were just staggering.

Again, I am not trying to be antagonistic, however, the idea that someone did a controlled demolition is pure conspiracy theory and bad science.

Finally, I heard that these fellas picked their "peers" for peer review.

This is not the scientific method. These people are not scientists, but activists with a scientific agenda. I call them scienticians.

I'll leave the last word to you. If you want to read it, fair enough. Just keep in mind that you are reading the National Inquirer of Science.

IrelandSpirit · 22-08-2010 4:11pm

FISMA wrote: »

Sorry if the tone appears antagonistic, it is not meant to be.

Have you ever watched those moon landing was a hoax shows, or visited their sites? If that's all you read, they make a pretty good case.

Then you go to a myth-buster type site and they totally pick apart the argument.

Have any of the people, like Jones, spoken in a Public forum and taken questions?

The link you provides cites the following
http://www.bentham-open.org/pages/content.php?TOCPJ/2009/00000002/00000001/7TOCPJ.SGM

Which looks very technical, however, I never heard of them. They seem new on the science block - this study is volume 2 and only a handful of articles. They are cherry picking. Sounds more like self-promotion to me.

Why not go to the well established scientific reviews? Because it does not pass a stink test.

So, they had to use and SEM to find nano-particles? What did they find?

They use the term "Active Thermitic Material." What is that? Sounds like a flux capacitor. It's so nebulous. If they found thermite, they would have stated it, but they did not. Neither are any graphs therein showing thermite.

It's kind of like having trace amounts of ethanol in water and saying that you are drinking rocket fuel.

I find it incredulous that anyone would think a building could survive that collision with a plane, the kinetic energy and momentum were just staggering.

Again, I am not trying to be antagonistic, however, the idea that someone did a controlled demolition is pure conspiracy theory and bad science.

Finally, I heard that these fellas picked their "peers" for peer review.

This is not the scientific method. These people are not scientists, but activists with a scientific agenda. I call them scienticians.

I'll leave the last word to you. If you want to read it, fair enough. Just keep in mind that you are reading the National Inquirer of Science.

Thanks. Ok, I suppose I'd better reiterate that for the purpose of this thread, my intention was to explore the science behind the collapse of the buildings themselves. Only that. The laws of nature should establish what is true without the need to form conspiracy theories about the scientists involved, or resort to name-calling.

I'm personally not interested in discussing whether or not the scientists involved are lying, not here. I would've thought this is not the place for it.

As regards that Thermite Paper, it was peer reviewed nonetheless. I have no reason to suspect foul play.

The fact remains. Three buildings collapse, symmetrically into their foundations, with the third building (WT7) collapsing despite comparatively little damage. No plane hit WT7. It suffered superficial damage from falling debris, and an office fire on the upper floor.

WT7 being the only known building of that spec to have been demolished (ostensibly) due to an office fire. To my knowledge, no official (NIST) explanation has been given as regards what caused the building to collapse in such a uniform manner, or how it achieved near freefall speed in its decent - a phenomena also commonly seen in controlled demolitions:

This video tracks the motion of the NW corner of Building 7 of the World Trade Center on 9/11 2001. For a period of ~2.5 seconds. This means it was falling through itself for over 100 feet with zero resistance, an impossibility in any natural scenario. This period of freefall is solid evidence that explosives had to be used to bring the building down. In the final draft for public comment (August 2008) NIST denied that WTC7 fell at freefall. In the final report in Nov 2008 they reversed themselves and admitted freefall, but denied its obvious significance.

http://www.youtube.com/watch?v=rVCDpL4Ax7I

There is also a WTC7 Measurement FAQ page for the above: http://www.911speakout.org/WTC7-Measu...

In any case, thanks for giving me the last word, though I was hoping that perhaps you would've had more to say? but that's ok. I'll post this video analysis of the collapse of the North Tower too, for prosperity, in case anybody else wishes to discuss it:

The wave of horizontal mass ejection moving down the face of the North Tower of the World Trade Center is shown to move faster than heavy debris falling through air nearby. See http://www.911speakout.org for more.

http://www.youtube.com/watch?v=eXSHm3CdHf4

And here's another take on it, which appears to contradict the above:

Proof to any reasonable person that the World Trade Center towers fell considerably slower than free fall speed.

http://www.youtube.com/watch?v=DoOp40E6UZg&feature=related

locum-motion · 23-08-2010 6:43pm

IrelandSpirit wrote: »

... I'll post this video analysis of the collapse of the North Tower too, for prosperity, ...

I'll look at these when I get home tonight, but in the meantime, thanks for your concern that we should prosper.

Or did you perhaps mean 'posterity'?

IrelandSpirit · 23-08-2010 7:28pm

locum-motion wrote: »

I'll look at these when I get home tonight, but in the meantime, thanks for your concern that we should prosper.

Or did you perhaps mean 'posterity'?

Well indeed, I meant posterity, but ... considering the gravity of this topic perhaps a healthy desire for prosperity is not inappropriate?

Please do have a look at those vids whenever you have time, and please bear in mind they are very short; more in-depth analyses can be found on their site.

Also, I'll just quickly say that I'm not well-versed in science as regards this topic, past a rudimentary grasp of Newtons laws, a little knowledge of Victorian engineering and some direct experience of building work ...

Thanks.

Xios · 24-08-2010 12:32pm

Irelandspirit.
It seems to me that you've come to a conclusion about the events and are working backwards to find evidence for your ideas. Going down this route, you are going to be strongly convinced by some evidence that proves you right while ignoring everything that contradicts your idea.

'In my opinion' there was no such thing as a controlled demolition. The sheer chaos of a 833,000 lb aeroplane slamming into a building at those speeds is a very substantial amount of force. Factor that in with burning jet fuel, plastics and furniture over time, the building had no chance. As for the collapse. The huge amount of weight bearing down on those critical few floors would surely begin the collapse. the rest was like crushing a plastic cup, everything went down and outwards.
Falling debree would've damaged surrounding buildings sufficiently to cause collapse.

edit /Think of castles that have fallen to trebuchets, using only 50 lb rocks.

Morbert · 24-08-2010 12:33pm

IrelandSpirit wrote: »

Hiya, I recently came across this short video, which explains (ostensibly) the science behind a gravity-driven demolition. I would seriously appreciate your take on it:

http://www.youtube.com/watch?v=NiHeCjZlkr8&feature=player_embedded

I do realise it is related to the collapse of the Twin Towers, and this is not a CT forum, I'm asking only if the explanation given in the video is scientifically correct. Or at least consistent with Newtonian physics, as claimed.

I also ask the Mods to please respect this line of inquiry; it is purely the science I'm interested in here, NOT conspiracy theories, and the physics forum was recommended as the best place to ask.

Thank you in advance for any help you might provide.

The WTC used steel trusses to support its structure. If these are weakened and expanded (by, say, a 1000 Fahrenheit fire), they go slack, and you have a near free-fall collapse.

IrelandSpirit · 25-08-2010 12:07am

Xios wrote: »

Irelandspirit.
It seems to me that you've come to a conclusion about the events and are working backwards to find evidence for your ideas. Going down this route, you are going to be strongly convinced by some evidence that proves you right while ignoring everything that contradicts your idea.

Not at all. To arrive at a conclusion about the events, I would need to be 100% certain of the events. I am not 100% certain and it is the reason I started this thread here. I do, therefore, have some questions as regards what we're told happened.

BTW, these are not my ideas, I am neither an architect nor an engineer, but they are:
http://www.ae911truth.org/

'In my opinion' there was no such thing as a controlled demolition. The sheer chaos of a 833,000 lb aeroplane slamming into a building at those speeds is a very substantial amount of force. Factor that in with burning jet fuel, plastics and furniture over time, the building had no chance. As for the collapse. The huge amount of weight bearing down on those critical few floors would surely begin the collapse. the rest was like crushing a plastic cup, everything went down and outwards.

An aeroplane slamming into a building at great speeds will generate a substantial amount of force, I agree. But for the 'crushing a plastic cup' effect to work, wouldn't the upper floors of the building need to be exerting a greater force than the combined resistance offered by the lower floors? Would the weight of the upper floors (about 20) be sufficient to crush all the floors beneath? (About 90 of them)

Or would the combined resistance offered by the lower floors need to be greatly reduced in some way. And reduced uniformly throughout all 90 or so floors beneath the impact zone, to achieve a uniform, symmetrical collapse at freefall or near freefall speeds. No? Otherwise we'd expect the building would topple over in its collapse, or (most likely in my current opinion) it would not collapse at all.

Falling debree would've damaged surrounding buildings sufficiently to cause collapse.

Please have a look at this footage of WT7 collapsing, it's only about 9 seconds long because that's about how fast it collapsed.

https://www.youtube.com/watch?v=LD06SAf0p9A

Bear in mind it is a 47-story steel-frame skyscraper:

Collapse of 7 World Trade Center
... a 47-story steel-frame skyscraper.

http://en.wikipedia.org/wiki/Collapse_of_the_World_Trade_Center#Collapse_of_7_World_Trade_Center

What caused this building to collapse? Damage from falling debris and an office fire in the upper floor? I think Newton would have a word or two to say about that! No, I'm not convinced by the 'falling debris' explanation.

edit /Think of castles that have fallen to trebuchets, using only 50 lb rocks.

(Trebuchets! Love them - wanted to build one in back garden a few years back)

IrelandSpirit · 25-08-2010 12:23am

Morbert wrote: »

The WTC used steel trusses to support its structure. If these are weakened and expanded (by, say, a 1000 Fahrenheit fire), they go slack, and you have a near free-fall collapse.

Hmmm, perhaps it would. Did temperatures reach that high, and over the entire structural support of the building (or significant portion thereof) to cause a total collapse at near free-fall speed?

Xios · 25-08-2010 12:56am

IrelandSpirit wrote: »

But for the 'crushing a plastic cup' effect to work, wouldn't the upper floors of the building need to be exerting a greater force than the combined resistance offered by the lower floors? Would the weight of the upper floors (about 20) be sufficient to crush all the floors beneath? (About 90 of them)

Or would the combined resistance offered by the lower floors need to be greatly reduced in some way. And reduced uniformly throughout all 90 or so floors beneath the impact zone, to achieve a uniform, symmetrical collapse at freefall or near freefall speeds. No? Otherwise we'd expect the building would topple over in its collapse, or (most likely in my current opinion) it would not collapse at all.

It's about momentum and kinetic energy. 20 Floors of that structure falling 3-4 storeys is a lot of force, watch this video. The same principle applies.

http://www.youtube.com/watch?v=YIUmfXXe0v4

Morbert · 25-08-2010 10:44am

IrelandSpirit wrote: »

Hmmm, perhaps it would. Did temperatures reach that high, and over the entire structural support of the building (or significant portion thereof) to cause a total collapse at near free-fall speed?

The fire definitely reached 1000 Fahrenheit, and may have reached over 1500. And if even a small section of the trusses are weakened, they all go slack all along the building, and any support they provide goes completely. This might seem like a design oversight, but you can't blame the architects for not anticipating a jet-fuel fire.

Xios · 25-08-2010 12:02pm

Morbert wrote: »

This might seem like a design oversight, but you can't blame the architects for not anticipating a jet-fuel fire.

Every decision can be easily scrutinised in hindsight. So yeah, we can't blame them.

Podman · 25-08-2010 4:28pm

I remember back in the 80's there was a documentary about the twin towers, from what I can remember they were specifically designed to withstand a jet collision because they were so tall.

It is very obviously out of place how both towers collapsed within hours, in their own footprints, exactly like demolitions. Neither toppled over sideways, as would be expected.

There are also numerous eyewitnesses that testify to explosions before the collapses, just like wtc7.

These are some small parts from an engineers report...

The Federal Emergency Management Agency (FEMA) report into collapse of the WTC towers, estimates that about 3,500 gallons of jet fuel burnt within each of the towers. Imagine that this entire quantity of jet fuel was injected into just one floor of the World Trade Center, that the jet fuel burnt with perfect efficency, that no hot gases left this floor, that no heat escaped this floor by conduction and that the steel and concrete had an unlimited amount of time to absorb all the heat. With these ideal assumptions we calculate the maximum temperature that this one floor could have reached.

Quote from the same page:
What we propose to do, is pretend that the entire 3,500 gallons of jet fuel was confined to just one floor of the World Trade Center, that the jet fuel burnt with the perfect quantity of oxygen, that no hot gases left this floor and that no heat escaped this floor by conduction. With these ideal assumptions (none of which were meet in reality) we will calculate the maximum temperature that this one floor could have reached. Of course, on that day, the real temperature rise of any floor due to the burning jet fuel, would have been considerably lower than the rise that we calculate, but this estimate will enable us to demonstrate that the "official" explanation is a lie.

In the mid-1990s British Steel and the Building Research Establishment performed a series of six experiments at Cardington to investigate the behavior of steel frame buildings. These experiments were conducted in a simulated, eight-story building. Secondary steel beams were not protected. Despite the temperature of the steel beams reaching 800-900° C (1,500-1,700° F) in three of the tests (well above the traditionally assumed critical temperature of 600° C (1,100° F), no collapse was observed in any of the six experiments.

Morbert · 25-08-2010 6:17pm

Podman wrote: »

I remember back in the 80's there was a documentary about the twin towers, from what I can remember they were specifically designed to withstand a jet collision because they were so tall.

Source?

It is very obviously out of place how both towers collapsed within hours, in their own footprints, exactly like demolitions. Neither toppled over sideways, as would be expected.

Both buildings took damage that was more-or-less evenly distributed through the floors struck. I say, more-or-less because the south tower took more damage to its north side and hence did not fall on its own footprint.

There are also numerous eyewitnesses that testify to explosions before the collapses, just like wtc7.

There are numberous eyewitnesses that testify to alien abductions. If they are not documented with video then they're not much good.

These are some small parts from an engineers report...

Quote from the same page:
What we propose to do, is pretend that the entire 3,500 gallons of jet fuel was confined to just one floor of the World Trade Center, that the jet fuel burnt with the perfect quantity of oxygen, that no hot gases left this floor and that no heat escaped this floor by conduction. With these ideal assumptions (none of which were meet in reality) we will calculate the maximum temperature that this one floor could have reached. Of course, on that day, the real temperature rise of any floor due to the burning jet fuel, would have been considerably lower than the rise that we calculate, but this estimate will enable us to demonstrate that the "official" explanation is a lie.

Again, steel trusses, not just beams, were responsible for most the Towers' support. The trusses would be much more susceptible to fire than the beams.

IrelandSpirit · 25-08-2010 6:20pm

Xios wrote: »

It's about momentum and kinetic energy. 20 Floors of that structure falling 3-4 storeys is a lot of force, watch this video. The same principle applies.

http://www.youtube.com/watch?v=YIUmfXXe0v4

I can totally understand what you're saying, 20 or so floors (it was actually less, 13-14 floors) falling from a gap 3-4 storeys high it is a lot of force, but I just don't think it would be sufficient to crush the entire steel structure, all the remaining 93 concrete floors AND in a symmetrical collapse at near freefall speeds - and certainly not in the case of WT7 where structural integrity was comparatively intact and no such force was present.

This is what I don't understand. I just can't envisage it ...

And I am prepared to accept the temperature theory, that the steel melted, was weakened due to jet fuel fire etc - but you'd need to sustain the temperatures of a blowtorch over a considerable amount of time: the steel would need to glow red hot, literally, to melt and then somehow reduce the combined resistance offered by the entire steel structure of all 93 floors below. It would've also had to have happened uniformly - if some parts weakened more than others the building would topple.

And again, nothing of the sort happened in the case of WT7.

This is one of the first presentations by Richard Gage, a practising architect for over 20 years, who works with steel frame designs. The explanation given here is detailed and appears well-researched.

http://video.google.com/videoplay?docid=-8182697765360042032#

BTW, I'm having problems embedding video too.

Morbert · 25-08-2010 6:29pm

IrelandSpirit wrote: »

I can totally understand what you're saying, 20 or so floors (it was actually less, 13-14 floors) falling from a gap 3-4 storeys high it is a lot of force, but I just don't think it would be sufficient to crush the entire steel structure, all the remaining 93 concrete floors AND in a symmetrical collapse at near freefall speeds - and certainly not in the case of WT7 where structural integrity was comparatively intact and no such force was present.

This is what I don't understand. I just can't envisage it ...

And I am prepared to accept the temperature theory, that the steel melted, was weakened due to jet fuel fire etc - but you'd need to sustain the temperatures of a blowtorch over a considerable amount of time: the steel would need to glow red hot, literally, to melt and then somehow reduce the combined resistance offered by the entire steel structure of all 93 floors below. It would've also had to have happened uniformly - if some parts weakened more than others the building would topple.

And again, nothing of the sort happened in the case of WT7.

This is one of the first presentations by Richard Gage, a practising architect for over 20 years, who works with steel frame designs. The explanation given here is detailed and appears well-researched.

http://video.google.com/videoplay?docid=-8182697765360042032#

BTW, I'm having problems embedding video too.

Remember that it wasn't simply a jet-fuel fire. It was a jet-fuel fire couple with trauma from a jet collision.

http://www.debunking911.com/impact.htm

This kind of support destruction would be more than enough to destroy the floors below. In fact, it seems I was even being generous with my description of a near free-fall collapse.

http://www.debunking911.com/freefall.htm

garancafan · 25-08-2010 6:45pm

FISMA wrote: »

It's kind of like having trace amounts of ethanol in water

Were you referring to Budweiser?:rolleyes:

IrelandSpirit · 25-08-2010 6:47pm

Morbert wrote: »

Remember that it wasn't simply a jet-fuel fire. It was a jet-fuel fire couple with trauma from a jet collision.

http://www.debunking911.com/impact.htm

This kind of support destruction would be more than enough to destroy the floors below. In fact, it seems I was even being generous with my description of a near free-fall collapse.

http://www.debunking911.com/freefall.htm

Thanks. I'll have a look at those vids.

IrelandSpirit · 26-08-2010 6:14pm

There was some good arguments made on that site, I thought anyway, and yet the jury is still out in my mind.

The 14 floors fell 12ft, about 4m, (not 3 storeys, I was being generous too), reaching speeds of 19mph in the case of WTC1. So I'm not 100% convinced by the 'crushing plastic cup' effect of top floors falling, especially as the top portion was destroyed in first 4 seconds of descent.

WT7 fell in around 6.5 seconds, not 16 seconds. And it fell vertically, not sideways, and with no resistance - not one column resisted hence the speed and symmetry of collapse. Something must have caused each of the fifty perimeter columns to fail, sequentially, to account for this. Fire alone would not do it.

And the NIST report itself says there was not significant damage from falling debris to cause collapse of WT7. Also, the surrounding buildings WTC3, 4, 5 & 6, sustained considerable more damage and yet were left standing.

There are many more questions still left unanswered ...

Morbert · 26-08-2010 7:15pm

IrelandSpirit wrote: »

There was some good arguments made on that site, I thought anyway, and yet the jury is still out in my mind.

The 14 floors fell 12ft, about 4m, (not 3 storeys, I was being generous too), reaching speeds of 19mph in the case of WTC1. So I'm not 100% convinced by the 'crushing plastic cup' effect of top floors falling, especially as the top portion was destroyed in first 4 seconds of descent.

WT7 fell in around 6.5 seconds, not 16 seconds. And it fell vertically, not sideways, and with no resistance - not one column resisted hence the speed and symmetry of collapse. Something must have caused each of the fifty perimeter columns to fail, sequentially, to account for this. Fire alone would not do it.

And the NIST report itself says there was not significant damage from falling debris to cause collapse of WT7. Also, the surrounding buildings WTC3, 4, 5 & 6, sustained considerable more damage and yet were left standing.

Much of the evidence regarding the WTC7 collapse came after the NIST report. It was found that the building not only had a massive fire, but also a 20 story hole in it.

http://www.debunking911.com/WTC7.htm

There are many more questions still left unanswered ...

It clear that the collapse of the WTC buildings was not the result of controlled demolitions, and that conspiracies regarding the collapse are just that:conspiracies.

IrelandSpirit · 26-08-2010 7:45pm

Morbert wrote: »

Much of the evidence regarding the WTC7 collapse came after the NIST report. It was found that the building not only had a massive fire, but also a 20 story hole in it.

http://www.debunking911.com/WTC7.htm

It clear that the collapse of the WTC buildings was not the result of controlled demolitions, and that conspiracies regarding the collapse are just that:conspiracies.

If the massive hole was the cause of the collapse, then why didn't the building topple over? How do you account for the symmetrical collapse?

Morbert · 27-08-2010 11:45am

IrelandSpirit wrote: »

If the massive hole was the cause of the collapse, then why didn't the building topple over? How do you account for the symmetrical collapse?

There was no symmetrical collapse. The north wall fell in around 7 seconds, but the full collapse started well before that. The collapse propagated outwards.

http://www.youtube.com/watch?v=OUkvnfV606w

In this video, you can see the penthouse collapse from fire. This collapse propagates to the support structures, causing the whole building to go slack and fall.

As for why the building didn't topple over. WTC7, like the towers, was specifically designed not to topple over, unlike the small concrete buildings conspiracy theorists often show.

Xios · 27-08-2010 12:17pm

IrelandSpirit wrote: »

If the massive hole was the cause of the collapse, then why didn't the building topple over? How do you account for the symmetrical collapse?

Dude, seriously...
A bunch of pissed off muslims took down the towers. You say that 14 floors falling 4m is not enough to collapse the whole building. It never needed to, it just needed to break the floor below it, once that happened, the next would break and so on.

You're ommiting the fact that heated steel is very weak and bendy. Fire blazed concrete cracks and crumbles. When someone tells you that the fire needed to reach 2000 degrees to have melted steel, i just tell them, (do you need to melt a spoon to break it?)

You've become a victim of conspiracy propaganda. There are hundreds of people and videos looking at tiny details and making up assumptions to what they mean, like the debree flying out from the lower floors before the initial collapse wave, how would you explain that?

IrelandSpirit · 27-08-2010 12:39pm

Morbert wrote: »

There was no symmetrical collapse. The north wall fell in around 7 seconds, but the full collapse started well before that. The collapse propagated outwards.

http://www.youtube.com/watch?v=OUkvnfV606w

In this video, you can see the penthouse collapse from fire. This collapse propagates to the support structures, causing the whole building to go slack and fall.

I find it difficult to believe the penthouse collapsing took down the entire building with it. It looks like the penthouse collapses because the building's support structures failed - the inner columns - and not the other way around.

And thing is: WT7 was 47 storeys, was the fire hot enough to cause the whole building to go slack and fall? temperatures equivalent to a blow torch?

Remember, no plane struck it so there was no jet-fuel to feed the fire.

As for why the building didn't topple over. WTC7, like the towers, was specifically designed not to topple over, unlike the small concrete buildings conspiracy theorists often show.

Is that a conspiracy theory? Sorry, not here to discuss CTs. I'd say all buildings are designed not to topple over, not just the WTC1,2 and 7.

Or did you mean that only those 3 buildings were specifically designed not to topple over as they collapsed?

True, they were the only 3 buildings to collapse that day and not topple over. But what you assert here is a typical requirement of a controlled demolition. And I can't think of any building which has that specification pre-engineered into it's design.

IrelandSpirit · 27-08-2010 1:17pm

Xios wrote: »

Dude, seriously...
A bunch of pissed off muslims took down the towers. You say that 14 floors falling 4m is not enough to collapse the whole building. It never needed to, it just needed to break the floor below it, once that happened, the next would break and so on.

You're ommiting the fact that heated steel is very weak and bendy. Fire blazed concrete cracks and crumbles. When someone tells you that the fire needed to reach 2000 degrees to have melted steel, i just tell them, (do you need to melt a spoon to break it?)

You've become a victim of conspiracy propaganda. There are hundreds of people and videos looking at tiny details and making up assumptions to what they mean, like the debree flying out from the lower floors before the initial collapse wave, how would you explain that?

If you believe I've 'become a victim of conspiracy propaganda', you are wrong. I seriously don't know what to believe anymore. For a long time now I have been questioning the alternative theories and the official version of events too, and have come to no definitive conclusion.

It is the reason I came here.

I believed you guys might be able to explain things in a coherent and rational manner.

I'd of hoped that asking in a science forum I would have the answers to questions like how did 'the debree fly out from the lower floors before the initial collapse wave?' And how did the fire become hot enough to bring down WT7? And how did WTC7 collapse without toppling over? And no, it was not a built-in specification, sorry, I do not accept the assertion that the only three buildings to collapse were designed to do so symmetrically.

And yes, agreed, it may very-well be '"a bunch of pissed off muslims took down the towers", as you say. But please read the OP. I'm only interested in questions as regards the 'how' of it, not the 'who.'

Xios · 27-08-2010 1:30pm

On the blasts.
One would think they are explosions, as they look like them. But when you think about what else is happening. The whole building above is coming down and displacing a huge volume of air, creating a pressure wave that would've travelled down elevator shafts and burst out at the weakest points or where the elevator doors were already open.

gravity-driven demolition, question ...

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