A mind numbing amount of explosives

[FactCheck]

I would like to know if anyone could calculate how much explosives would be needed to

1) Create a molten pool for 3 months

2) Cut the columns on all floors to remove resistance

3) Throw the columns 300 feet in large 20-30 story sections

Sounds like a mind numbing amount which makes hiding it laughable. Heh!

[R.Mackey]

Ballpark figures:

1) Not really credible at any amount, though you didn't describe the size of the pool. Recall that TNT is about ten times less energetic, pound for pound, than jet fuel. The DELTA group (http://delta.ucdavis.edu/WTC.htm) estimated the amount of heat energy in combustibles between the two WTC Towers was on the order of 20 kilotons TNT equivalent. Also, if all that heat was applied at once rather than gradually, the heat loss through radiation would be far higher, since it would start at a vastly higher temperature rather than being sustained at a smouldering or burning temperature. That amount of explosives would surely disperse any such "pool."

Even atomic bombs detonated on the desert sands don't create long-lasting pools of liquid. Nor do those detonated deep in the ground create lasting bubbles of molten rock.

2) Approximately 150 kg TNT per floor cut, after the energy estimate in Greening (http://www.911myths.com/WTCREPORT.pdf). Perhaps a factor of two or three less on average, taking into account the tapering column geometry and the possibility of drilling or otherwise weakening columns before detonation. If not ideally placed, e.g. can't cut wallboard so you have to use cratering charges stood off a couple of inches, multiply by several.

3) Roughly 2000 kg, if thrown from the 50th floor. For the third time in as many days, see the post here (http://forums.randi.org/showthread.php?postid=2854264#post2854264) and elsewhere in the thread.

ETA: Fascinating paper on atomic test melting here (https://e-reports-ext.llnl.gov/pdf/329450.pdf). (Yes, it's a strange "https" address, not sure why; I had no problems opening it. It's from the Lawrence Livermore servers, not a questionable site.)

[gumboot]

Don't forget you need to add:

4) Pulverise all of the concrete in both towers.

-Gumboot

[nicepants]

I would like to know if anyone could calculate how much explosives would be needed to...

...substantially more than would have been able to be installed without someone noticing, or during Scott Forbes' mysterious "power down"

[einsteen]

I would like to know if anyone could calculate how much explosives would be needed to

1) Create a molten pool for 3 months

2) Cut the columns on all floors to remove resistance

3) Throw the columns 300 feet in large 20-30 story sections

Sounds like a mind numbing amount which makes hiding it laughable. Heh!

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.

[TheRedWorm]

Are we talking about explosives or therm*te here, E?

[DavidJames]

Are we talking about explosives or therm*te here, E?Along the same lines, are you talking real science or CT science?

[defaultdotxbe]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.
so how much explosives would be needed to produce each observed phenomenon at ground zero?

[LastChild]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.

Exactly. But remember some people have minds that tend to get numb.

[GStan]

I would like to know if anyone could calculate how much explosives would be needed to

1) Create a molten pool for 3 months

2) Cut the columns on all floors to remove resistance

3) Throw the columns 300 feet in large 20-30 story sections

Sounds like a mind numbing amount which makes hiding it laughable. Heh!

Is this a trick question?

The correct answer is that no explosives would be needed.

[Alferd_Packer]

This is not really a good argument, since, obviously no explosives were in fact used, but all of these effects* were due to the shear energy of the collapse.

(*Well actually none of these effect actually occurred)

What is more important is to ask the truthers to calculate just how much explosives would have been needed for their scenario, just an order of magnitude in TNT. (i.e. was it 100 lbs of TNT, 1000 lbs of TNT, 10,000 lbs of TNT, etc)

[twinstead]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.

It's not like we're claiming the two choices are either explosives brought down the building or it spontaneously collapsed for no reason. A lot of the effects of the collapse subsequent to this 'catalyst' are attributed to the 'explosives' themselves by many truthers.

[jujigatami]

Just to play devils advocate a little:

I don't think it would take a mind numbing amount of explosives. Sure, it would take a lot, but if you could place a bomb, say the size of a 2 drawer file cabinet next to almost every core column and detonated them, I would think you would damage enough core columns to cause collapse. I mean a file cabinet could hold probably 150-200 pounds of explosive each. Multiply that bythe number of core columns, and its not so much, especially if its brought in in small file cabinets a few at a time... or even all at once as a moving company bringing a couple hundred file cabinets into a gigantic office building wouldn't raise many eyebrows.

Now, understand, I AM NOT FOR A SECOND SAYING THAT I THINK THIS IS WHAT HAPPENED!!!!!

But lets face it, the towers, or any building for that matter could be brought down with explosives, and not so many that it would be impossible to do.

Of course, it would probably be easier and more effective to just hijack an airliner and crash it in to the building.

[DGM]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.
And for that all the "truthers" would have to do is show that there was a deficiency in the amount of energy to produce a global collapse. Or that there was something lacking in the theories for the collapse initiation. Maybe a credible structural engineer could work on that for you. Should we expect this anytime soon?

[Gravy]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.Nope. This is about conspiracists' claims that the three effects listed in the OP were caused by explosives and incendiaries because they could not have occurred through "natural" means.

Just to play devils advocate a little:

I don't think it would take a mind numbing amount of explosives. Sure, it would take a lot, but if you could place a bomb, say the size of a 2 drawer file cabinet next to almost every core column and detonated them, I would think you would damage enough core columns to cause collapse.See my answer above. It's not just about collapse, it's about everything the conspiracists say was done (throw in pulverizing all the concrete in mid-air, and creating pyroclastic flows of expanding gas and dust, while you're at it.

The conspiracists are living in a world of science fiction and fantasy.

[FactCheck]

Nope. This is about conspiracists' claims that the three effects listed in the OP were caused by explosives and incendiaries because they could not have occurred through "natural" means.

See my answer above. It's not just about collapse, it's about everything the conspiracists say was done (throw in pulverizing all the concrete in mid-air, and creating pyroclastic flows of expanding gas and dust, while you're at it.

The conspiracists are living in a world of science fiction and fantasy.


They want to argue that the building could not have fallen the way it did unless the resistance was removed. When you point out how much explosives you would need they always forget to match the amount needed for the conspiracy story. Heh!

[jujigatami]

Gravy,

I don't know if I buy that.

I mean, no amount of explosives will create pools of molten metal for months, because that's not what explosives do.

All I was saying is that it wouldn't take a "mind numbing" amount of explosives to take down the WTC or really almost any high rise.

If there were explosives on every core column in the towers on some floor up pretty high, it would cause a collapse, and aside from the many explosions that would be seen and heard for miles around, the collapse would look about the same- Upper mass falling and crushing the lower mass, the dust cloud (call it whatever you want), the columns being thrown, etc.

I'm not talking about the truther stupidity.

I'm just saying I believe that it could be possible to bomb a building, with a not very mind numbing amount of explosives (like several tons, but not hundreds of tons), and have it collapse looking a lot like the WTC did.

I also believe that the WTC collapse could have been achieved with explosives. NOT THAT IT WAS! Simply that if enough explosives could have been smuggled in and placed near enough to the core columns and detonated it would weaken the core columns in the same way that the plane impact and the subsequent fire did.

Its not mind numbing to think that terrorists might try to do that. They wouldn't need to weaken columns, remove drywall, or run miles of wire either. It could happen. It didn't, but it could have. And if the terrorists did manage to blow up the towers with bombs, we'd have truthers screaming something along the lines of "why would a bunch of arabs living in caves engage in a plan that would have been so easy to catch? Why wouldn't they just hijack planes and ram them in to the towers?"

Sure, a plan like that probably wouldn't succeed (and would have to involve a couple of office managers and security guards). Heck, they'd probably be caught pretty easily, but I've worked in big buildings with big companies and it isn't impossible to think that it could happen.

Of course, here is my disclaimer: I do not for even a second believe that any explosives were used in the 9/11 attacks.

I hope I'm being clear and that no one reading this thinks that I buy in to any truther nonsense.

[Apollo20]

On February 26th 1993 an incorrectly placed bomb almost succeeded in toppling the North Tower!

That bomb was 1200 pounds of urea nitrate pumped up with some nitroglycerine and boosted with lead azide, magnesium, ferric oxide and three canisters of hydrogen gas. The TNT equivalent of high explosive would be about 1 tonne!

So I would say that about 2 tonnes of well-placed HE might just do it.....

[Quad4_72]

On February 26th 1993 an incorrectly placed bomb almost succeeded in toppling the North Tower!

That bomb was 1200 pounds of urea nitrate pumped up with some nitroglycerine and boosted with lead azide, magnesium, ferric oxide and three canisters of hydrogen gas. The TNT equivalent of high explosive would be about 1 tonne!

So I would say that about 2 tonnes of well-placed HE might just do it.....

It almost succeeded huh? And by almost succeeded you mean not even close right?

[Newtons Bit]

It almost succeeded huh? And by almost succeeded you mean not even close right?

No, it did almost succeed. The bomb itself didn't take out any columns, but it did severely damage a concre wall. This was a wall that retainined soil that confined large piers that made up the foundation for other parts of the structure.

Had that retaining wall collapsed, the soil around the surrounding foundations would have become loose, the foundations themselves would have been unsupported, buckled and collapse. This would lead to part of the building being supported and another not. The tower would have literally toppled like a tree.

One of the guys I work with went to a thingy (that's a technical term) hosted by Leslie Robertson on the towers not long after the bomb. Robertson said that is was a "when, not if" situation that the towers would collapse if the wall wasn't repaired.

[SDC]

No, it did almost succeed. The bomb itself didn't take out any columns, but it did severely damage a concre wall. This was a wall that retainined soil that confined large piers that made up the foundation for other parts of the structure.

Had that retaining wall collapsed, the soil around the surrounding foundations would have become loose, the foundations themselves would have been unsupported, buckled and collapse. This would lead to part of the building being supported and another not. The tower would have literally toppled like a tree.

One of the guys I work with went to a thingy (that's a technical term) hosted by Leslie Robertson on the towers not long after the bomb. Robertson said that is was a "when, not if" situation that the towers would collapse if the wall wasn't repaired.

If it had collapsed in 1993, just think of the fascinating problems you engineering types would be dealing with. And (in that alternate world) what the equivalents of our truthers would be claiming...

"It's obvious that it wasn't a bomb. It had to be an airplane, but a big stealth one. It just went plonk into the tower, and the whole thing fell over. Anyone who says there was no plane, and that it was a bomb, is a government shill!"

[beachnut]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.
Exactly why 9/11 truth thinks 9/11 looks like a CD, is why 9/11 makes CD look like 9/11. The energy to destroy buildings is primarily gravity. So 9/11 does not look like CD, CD looks like 9/11 (not the other way). This is the problem with people who lack knowledge. They make faulty analogies. You also need to spell out how you think the CD of the WTC took place; if you do not place the explosives on the steel in the proper way, you can not use a little explosives you have to tons. Therefore, if you have no evidence of CD, you have nothing to complain about. 9/11 truth makes mistakes, you really want to support outright lies and misinformation?

There were no explosives on 9/11. You never will have facts or evidence so why are you missing the point. The point is, and everyone knows this for a fact, some truthers have said (hoffman, jones) the concrete was all turned to dust (if not said they implied, go look it up)! Gravy says correctly this would take tons of explosives (making hoffmans total dust event), on the order of 116.1568 tons of TNT (Hoffman said so)! On the steel being ejected hundreds of feet, would take tons of explosives on the order of 2 to 10 tons per event. So please defend your ideas, if you have any on 9/11 with some facts. You missed the point on this one.

Hoffman also want more energy to make the dust cloud bigger and hotter, and one of the small part of heat energy he wants is equal to 985 TONS of TNT!!! Hoffman may be kind of nuts, but then why believe me, you must agree with his stuff, or you would point out how far gone this guy is. (Hoffman has another idea that needs 10 times that amount of energy!!) Hoffman, like most truthers bends the truth to say the "official story is not true", and he does this my making up BIG lies! You have you wagon hitched to the correct group.

Gravy is being conservative, and explaining this 9/11 truth topic perfectly. Good job Gravy, bad job 9/11 truth.

If you can not grasp simple ideas, it is no wonder why you grasp hearsay and lies of 9/11 truth. When you support these ideas please explain what happen to the sounds of explosives, or how thermite (a momentary reaction) can leave molten metal for weeks. Just explain what 9/11 truth really means. When they say the ejected column are proof of CD; what do they really mean? Since that is a false statement what do they really mean?

[Apollo20]

Beachnut:

The lack of explosive sounds is easy!

The explosions created a vacuum (that sucked the building down at faster than free fall don't you know), and sound doesn't travel in a vacuum!

[T.A.M.]

Well my vacuum must be unique then, as it is the noisiest SOB on the planet.

TAM;)

[Corsair 115]

Well my vacuum must be unique then, as it is the noisiest SOB on the planet.Wow, that must really suck.

:D :D

[FactCheck]

Gravy,

I don't know if I buy that.

I mean, no amount of explosives will create pools of molten metal for months, because that's not what explosives do.

All I was saying is that it wouldn't take a "mind numbing" amount of explosives to take down the WTC or really almost any high rise.

If there were explosives on every core column in the towers on some floor up pretty high, it would cause a collapse, and aside from the many explosions that would be seen and heard for miles around, the collapse would look about the same- Upper mass falling and crushing the lower mass, the dust cloud (call it whatever you want), the columns being thrown, etc.

I'm not talking about the truther stupidity.

I'm just saying I believe that it could be possible to bomb a building, with a not very mind numbing amount of explosives (like several tons, but not hundreds of tons), and have it collapse looking a lot like the WTC did.

I also believe that the WTC collapse could have been achieved with explosives. NOT THAT IT WAS! Simply that if enough explosives could have been smuggled in and placed near enough to the core columns and detonated it would weaken the core columns in the same way that the plane impact and the subsequent fire did.

Its not mind numbing to think that terrorists might try to do that. They wouldn't need to weaken columns, remove drywall, or run miles of wire either. It could happen. It didn't, but it could have. And if the terrorists did manage to blow up the towers with bombs, we'd have truthers screaming something along the lines of "why would a bunch of arabs living in caves engage in a plan that would have been so easy to catch? Why wouldn't they just hijack planes and ram them in to the towers?"

Sure, a plan like that probably wouldn't succeed (and would have to involve a couple of office managers and security guards). Heck, they'd probably be caught pretty easily, but I've worked in big buildings with big companies and it isn't impossible to think that it could happen.

Of course, here is my disclaimer: I do not for even a second believe that any explosives were used in the 9/11 attacks.

I hope I'm being clear and that no one reading this thinks that I buy in to any truther nonsense.

In other words you make the bomb do what the fires did. I think most would agree with that. The problem for conspiracy theorists is the loss of a key argument. "The building must have explosives because it fell too fast." If they think a few bombs could have done it then why was there no resistance? See the stupidity in their argument?

[FactCheck]

Lets see what we have so far...

1) I'm going to say it is the pool size of the molten metal pool in Jones paper. (Yes, the concrete pancaked floors which he says is molten metal. That's all we have from the conspiracy story.

2) Approximately 150 kg TNT per floor cut. Lets say it was the top 70 stories for argument sake. That's 10,500 kg (23,140 lbs) of tnt. How much C4? Thermite?

3) 2000 kg to through 20 to 30 stories of column trees 300 ft. (I know it was on another thread but the purpose for this thread is to add it all up.

4) To turn concrete into dust - no number yet

5) To super heat air and create a pyroclastic flow - no number yet.


Looks mind numbing to me...

[Gravy]

4) To turn concrete into dust - no number yetIIRC, in the Bazant, Le paper they calculated that it would take 311 tons of TNT per tower to reduce the concrete to the average particle size found in the dust, if the explosives were placed in closely-spaced holes drilled in the concrete. Explosives just aren't very efficient when it comes to turning concrete to dust.

[beachnut]

Beachnut:

The lack of explosive sounds is easy!

The explosions created a vacuum (that sucked the building down at faster than free fall don't you know), and sound doesn't travel in a vacuum!
So true.


Here is one of Hoffman's energy fantasies. http://www.physics911.ca/Hoffman:_The_North_Tower's_Dust_Cloud (http://www.physics911.ca/Hoffman:_The_North_Tower's_Dust_Cloud)

[jujigatami]

In other words you make the bomb do what the fires did. I think most would agree with that. The problem for conspiracy theorists is the loss of a key argument. "The building must have explosives because it fell too fast." If they think a few bombs could have done it then why was there no resistance? See the stupidity in their argument?

Like I said above... if you take the truthers stupidity into account, then there is NO amount of explosives that can do what they are saying. It is mind numbing.

[CHF]

Let's say that the new TM position is that a small amount of explosives would be needed to take down the towers.

Obviously the towers collapsed from the points of jet impact, so that's where the bombs would have to be. So what kind of bombs would survive the impacts and the fires?

And wouldn't a "small" amount of explosives completely contradict "squibs," pulverized concrete, etc?

[einsteen]

Beachnut:

The lack of explosive sounds is easy!

The explosions created a vacuum (that sucked the building down at faster than free fall don't you know), and sound doesn't travel in a vacuum!
Dr.G., you probably have never seen this video

http://youthfulindiscretions.com/vid/911/Extreme%20Closeup%20of%20World%20Trade%20Center%20 (WTC)%20Tower%20Collapse%20in%20New%20York%20City% 20(NYC)%20America%20after%20Plan.avi

Beachnut,

There are a lot of anomalies in the collapse. Let's try to solve it within the gravity driven point of view, I'll copy paste some of the posts I've made elsewhere. I would like to have a normal reaction, no rants and raves, insults intimidations etc. Only David B. Benson replied a little bit and someone called assbag, the latter mentioned the funneling of mass within the frames but IMHO that doesn't change the story at all. No LC reaction yet, they are too busy with the pentagon I guess
==========

The south tower's top section topples as we all know. It seems that some
rows of squibs (I know it is not the best word) or puffs appear when
the top block starts toppling. I've currently only synchronized two videos,
one with the camera perpendicular to the wall, in this direction the block
topples (it topples mainly in that direction and a little bit to the left).
The other video is from front/right, about 45 degrees very far away.

Let's go back to these videos (it's not needed to download them but they are here for reference)

http://rapidshare.com/files/80160735/911.wtc.2.demolition.headon.avi.html
http://rapidshare.com/files/82166625/south_tower_collapse.mpeg.html

We've seen before that when we take into account the distance that the rumbling sound already starts before a part of the top section hits the next floor.

But audio could be faked very easily, something that we've seen in the past. On the other hand it could also be that the sound of the first video is genuine but shifted in order to correct for the time delay. Personally I don't believe this because I've seen more videos that show this. But let's skip the audio and concentrate on the visual evidence.

The first video (and also the 2nd) show that there appears some rows of what is often called squibs. See the following animated gif:

http://i17.tinypic.com/8ekther.gif
http://i17.tinypic.com/8ekther.gif

If we synchronize both videos and extract some frames we get

http://i10.tinypic.com/6sum8a9.jpg (http://i10.tinypic.com/6sum8a9.jpg)
http://i3.tinypic.com/6y1bwcp.jpg (http://i3.tinypic.com/6y1bwcp.jpg)
http://i9.tinypic.com/71dr2vn.jpg (http://i9.tinypic.com/71dr2vn.jpg)
http://i6.tinypic.com/6yjwc2q.jpg (http://i6.tinypic.com/6yjwc2q.jpg)
The red line in the picture is the low part of the impact zone and the yellow lines are the locations where the squibs seem to originate. If we take the average of these four images we get the following

http://i18.tinypic.com/86ocrqa.jpg
http://i18.tinypic.com/86ocrqa.jpg

This easily shows that the average distance between the rows of squibs doesn't fit the height of a story. Although there is an error margin in the measurements it is absolutely clear that we see distinct rows, especially when you look at the videos in detail. The 2nd row clearly originates from the mechanical floors. The smoke colour is also different than the colour of the smoke at top, I don't know what that means but that's just an observation.

Since for the first video a width of 108 pixels is 64 meter the distance between the yellow lines is resp 14 and 20 pixels, i.e. 8.3 meter and 11.9 meter.

The distance of a story is known and that is roughly 3.78 meter. This means that it cannot be made plausible that the squibs are caused by the air pressed out, because

1) it doesn't fit with the distance between the floors
2) the top section topples, which means that the lowest floor of that section and the next one of the intact building cannot enclose the air. The effect could play a role later in the collapse when enough floors are pancaked and the situation becomes more symmetrical.
3) the velocity is relatively low in the beginning
4) if the top section breaks the concrete of the intact floors and the effect is due to the ejection of dust caused by these collisions then the distance should also be the same as in 1)

In the first video we also observe something else that is important, the following animated gif has been made for that

http://i6.tinypic.com/853hms5.gif
http://i6.tinypic.com/853hms5.gif

The left wall of the south tower (seen from video) is the right part of the animation. That object is more than 5 meter because it is about 10 pixels and therefore no human being.

The average image trick cannot be used here and I placed roughly white spots on the estimated centre of mass of the object, and did an image calculation with paint shop pro that takes the lightest of two pictures and then for a couple of extracted frames, this will give the following single picture with the trajectory of the object:

http://i3.tinypic.com/8eh9w2h.png

Here a parabole should be added into (I did that manually by the eye and not with least squares). In the video it almost looks like it is ejected from mid-air which is an optical illusion because of the dark smoke and debris around it. Therefore we have to assume it comes from the building. The object is ejected with about 13.6 m/s and comes from the building 10 pixels below the red line, that means

64 meter * 10/108 and that is about 5.9 meter under the red line.

If the top section falls with g (not 3g/4) then the speed it has reached could theoretically be 10.8 m/s, but if we shift the video back in time it seems that it is ejected at the moment that we have this situation

http://i16.tinypic.com/8faea0j.jpg
http://i16.tinypic.com/8faea0j.jpg

I'm sure if you work this out explicitly you will find that the maximum speed is lower than the speed of the ejected object. Oh yes I found a debunk already for that (a theoretical possibility) but I think the rows are more important

[Mancman]

The first video (and also the 2nd) show that there appears some rows of what is often called squibs. See the following animated gif:

http://i17.tinypic.com/8ekther.gif
http://i17.tinypic.com/8ekther.gif

Notice how the ejections of dust appear in a south to north direction.

This is exactly what we would expect considering the corner leading collapse was the southeast.

[defaultdotxbe]

The first video (and also the 2nd) show that there appears some rows of what is often called squibs. See the following animated gif:

http://i17.tinypic.com/8ekther.gif
http://i17.tinypic.com/8ekther.gif

so how much explosive is needed to make those squibs?

[beachnut]

Tell him if he says squibs, he has lost it.

You already did.

You squibs are floor failing and expelling air. Sorry, but you mean explosives, not squibs! Stop using squibs, they have been debunked. Explosives make a rapid ejection to slower effect, the escaping air accelerates from slower speed. Your stuff is going the wrong direction to be from an explosion. But your rows of continuous squibs are floors failing at faster and faster speeds. A floor can only hold so much debris and it fails, falling a the speed of the other mass that hit it and its new mass, the broken floor, and all of this is accelerated by gravity. The outer shell is damaged and being kick all over the place.

Funny stuff is your spacing, about 5 to 10 percent of being a multiple of a single floor!

10 percent is well within the range of your errors in your pixel plight of phantasy. See, just how big is a pixel again? Your pixels give you a resolution with in ONE meter. So your not a floor apart becomes, yes, multiples of floors. I think you can keep working on this, it is debunking the explosive guys even better as you learn more. Neat stuff. How long did it take you to do the pixel stuff? You got the multiple floors within 10 percent! That is good stuff considering you resolution is about 1 meter or worse. (I understand each pixel is 0.592 meter, but you can not measure any better than 1 meter or so with that)

[beachnut]

Dr.G., you probably have never seen this video
http://youthfulindiscretions.com/vid/911/Extreme%20Closeup%20of%20World%20Trade%20Center%20 (WTC)%20Tower%20Collapse%20in%20New%20York%20City% 20(NYC)%20America%20after%20Plan.avi

Can you turn up the sound any louder? Someone pushed the gain up too far. Sorry, not a single sound of explosive. Not even close. But I am sure if you push the gain up further, there will still be no sounds.

Many saw that video, before your friends rode the gain up, 6 years ago. Still no one heard explosives on 9/11, no one will now. Actual ears never heard explosives on 9/11. You may want to stick with thermite, it is newer than this video, Jones made it up 4 years after 9/11. That way your fantasy ideas with match a fantasy idea, better. The sound is busted. All the gain riding, and all the fake sounds can not fool those who heard the originals and those who we have shared 9/11 real memories with from that day. Pay attention, people there that day post here, they would tell you if they thought your ideas had merit.

[einsteen]

BeachN as I said before, I use that word "squib" because I have no other idea how to call it in English (ps explosive reaction doesn't require explosives, you remember). If this is explained properly then I again say: yeahhhh stupid now I see. I'm open for everything

[Apollo20]

Einsteen:

Those videos are VERY interesting for sure, but I would be very careful about how to interpret them and not jump to conclusions.

P.S. Nice avatar!

[beachnut]

BeachN as I said before, I use that word "squib" because I have no other idea how to call it in English (ps explosive reaction doesn't require explosives, you remember). If this is explained properly then I again say: yeahhhh stupid now I see. I'm open for everything
Squib just sounds silly. Use explosives, if you want explosives use them. Are the RDX, or what? Squib sounds funny and smacks of 9/11 truth.

Okay, tell me which explosive reaction we are talking about? I have yet to hear a coherent story on who, what, and how the WTC was blown up with some explosive reaction; except for terrorist, kill pilots, take planes, impact, fire, collapse.

Do not give up, but your calculation on the smoke coming out of the building happens on multiples of floors, well within a the tolerance of your measuring.

As for the deceleration of the object, that video is too short and clipped. Need a longer clip and you have to know what the object is; plus you have to measure just the vertical component, or the entire vector to see what the real speed is. If the piece is massive, it has to accelerate with gravity, or it has some magic dust on it to slow it down!

However, in the compression of the WTC the object could be ejected faster, much faster than the speed of collapse due to being ejected, like snapping out! The piece could slow down aerodynamically.

[FactCheck]

Dr.G., you probably have never seen this video

http://youthfulindiscretions.com/vid/911/Extreme%20Closeup%20of%20World%20Trade%20Center%20 (WTC)%20Tower%20Collapse%20in%20New%20York%20City% 20(NYC)%20America%20after%20Plan.avi

Beachnut,

There are a lot of anomalies in the collapse. Let's try to solve it within the gravity driven point of view, I'll copy paste some of the posts I've made elsewhere. I would like to have a normal reaction, no rants and raves, insults intimidations etc. Only David B. Benson replied a little bit and someone called assbag, the latter mentioned the funneling of mass within the frames but IMHO that doesn't change the story at all. No LC reaction yet, they are too busy with the pentagon I guess
==========

The south tower's top section topples as we all know. It seems that some
rows of squibs (I know it is not the best word) or puffs appear when
the top block starts toppling. I've currently only synchronized two videos,
one with the camera perpendicular to the wall, in this direction the block
topples (it topples mainly in that direction and a little bit to the left).
The other video is from front/right, about 45 degrees very far away.

Let's go back to these videos (it's not needed to download them but they are here for reference)

http://rapidshare.com/files/80160735/911.wtc.2.demolition.headon.avi.html
http://rapidshare.com/files/82166625/south_tower_collapse.mpeg.html

We've seen before that when we take into account the distance that the rumbling sound already starts before a part of the top section hits the next floor.

But audio could be faked very easily, something that we've seen in the past. On the other hand it could also be that the sound of the first video is genuine but shifted in order to correct for the time delay. Personally I don't believe this because I've seen more videos that show this. But let's skip the audio and concentrate on the visual evidence.

The first video (and also the 2nd) show that there appears some rows of what is often called squibs. See the following animated gif:

http://i17.tinypic.com/8ekther.gif
http://i17.tinypic.com/8ekther.gif

If we synchronize both videos and extract some frames we get

http://i10.tinypic.com/6sum8a9.jpg (http://i10.tinypic.com/6sum8a9.jpg)
http://i3.tinypic.com/6y1bwcp.jpg (http://i3.tinypic.com/6y1bwcp.jpg)
http://i9.tinypic.com/71dr2vn.jpg (http://i9.tinypic.com/71dr2vn.jpg)
http://i6.tinypic.com/6yjwc2q.jpg (http://i6.tinypic.com/6yjwc2q.jpg)
The red line in the picture is the low part of the impact zone and the yellow lines are the locations where the squibs seem to originate. If we take the average of these four images we get the following

http://i18.tinypic.com/86ocrqa.jpg
http://i18.tinypic.com/86ocrqa.jpg

This easily shows that the average distance between the rows of squibs doesn't fit the height of a story. Although there is an error margin in the measurements it is absolutely clear that we see distinct rows, especially when you look at the videos in detail. The 2nd row clearly originates from the mechanical floors. The smoke colour is also different than the colour of the smoke at top, I don't know what that means but that's just an observation.

Since for the first video a width of 108 pixels is 64 meter the distance between the yellow lines is resp 14 and 20 pixels, i.e. 8.3 meter and 11.9 meter.

The distance of a story is known and that is roughly 3.78 meter. This means that it cannot be made plausible that the squibs are caused by the air pressed out, because

1) it doesn't fit with the distance between the floors
2) the top section topples, which means that the lowest floor of that section and the next one of the intact building cannot enclose the air. The effect could play a role later in the collapse when enough floors are pancaked and the situation becomes more symmetrical.
3) the velocity is relatively low in the beginning
4) if the top section breaks the concrete of the intact floors and the effect is due to the ejection of dust caused by these collisions then the distance should also be the same as in 1)

In the first video we also observe something else that is important, the following animated gif has been made for that

http://i6.tinypic.com/853hms5.gif
http://i6.tinypic.com/853hms5.gif

The left wall of the south tower (seen from video) is the right part of the animation. That object is more than 5 meter because it is about 10 pixels and therefore no human being.

The average image trick cannot be used here and I placed roughly white spots on the estimated centre of mass of the object, and did an image calculation with paint shop pro that takes the lightest of two pictures and then for a couple of extracted frames, this will give the following single picture with the trajectory of the object:

http://i3.tinypic.com/8eh9w2h.png

Here a parabole should be added into (I did that manually by the eye and not with least squares). In the video it almost looks like it is ejected from mid-air which is an optical illusion because of the dark smoke and debris around it. Therefore we have to assume it comes from the building. The object is ejected with about 13.6 m/s and comes from the building 10 pixels below the red line, that means

64 meter * 10/108 and that is about 5.9 meter under the red line.

If the top section falls with g (not 3g/4) then the speed it has reached could theoretically be 10.8 m/s, but if we shift the video back in time it seems that it is ejected at the moment that we have this situation

http://i16.tinypic.com/8faea0j.jpg
http://i16.tinypic.com/8faea0j.jpg

I'm sure if you work this out explicitly you will find that the maximum speed is lower than the speed of the ejected object. Oh yes I found a debunk already for that (a theoretical possibility) but I think the rows are more important

HEHEHE, you can tell what he is looking at is aluminum siding. How do I know? Because column trees come in 3's and that's all by its lonesome. It also actually SLOWS DOWN on video...

LT8Vqw8oOn4

And the next one is even more laughable. The columns can clearly be seen getting pulled in before the so called "Squibs"/explosions, what ever... Heh!

http://video.google.com/videoplay?docid=-5405555553528290546&hl=en

Not a single explosion heard. I'm waitring for Jones to find magic fairy dust on the columns.:rolleyes:

[1337m4n]

Your question doesn't say whether potential energy is included. It is ridiculous to think that on the one hand an extreme amount is needed while on the other hand you believe that they are not needed at all. Only think about it as a catalyst.

Has NOBODY read this thread of mine (http://forums.randi.org/showthread.php?t=102612)??

The entire point of what the OP is saying, einsteen, is that if the explosives were "just a catalyst", then all of your "smoking guns" are gone. You are suggesting that only a small amount of explosives were used. How then do you explain the squibs without admitting that they don't contradict the "official story" at all?

I urge you to read my OP in that link. You will find it very insightful.

[gumboot]

Gravy,

I don't know if I buy that.

I mean, no amount of explosives will create pools of molten metal for months, because that's not what explosives do.

All I was saying is that it wouldn't take a "mind numbing" amount of explosives to take down the WTC or really almost any high rise.

If there were explosives on every core column in the towers on some floor up pretty high, it would cause a collapse, and aside from the many explosions that would be seen and heard for miles around, the collapse would look about the same- Upper mass falling and crushing the lower mass, the dust cloud (call it whatever you want), the columns being thrown, etc.

I'm not talking about the truther stupidity.

I'm just saying I believe that it could be possible to bomb a building, with a not very mind numbing amount of explosives (like several tons, but not hundreds of tons), and have it collapse looking a lot like the WTC did.

I also believe that the WTC collapse could have been achieved with explosives. NOT THAT IT WAS! Simply that if enough explosives could have been smuggled in and placed near enough to the core columns and detonated it would weaken the core columns in the same way that the plane impact and the subsequent fire did.

Its not mind numbing to think that terrorists might try to do that. They wouldn't need to weaken columns, remove drywall, or run miles of wire either. It could happen. It didn't, but it could have. And if the terrorists did manage to blow up the towers with bombs, we'd have truthers screaming something along the lines of "why would a bunch of arabs living in caves engage in a plan that would have been so easy to catch? Why wouldn't they just hijack planes and ram them in to the towers?"

Sure, a plan like that probably wouldn't succeed (and would have to involve a couple of office managers and security guards). Heck, they'd probably be caught pretty easily, but I've worked in big buildings with big companies and it isn't impossible to think that it could happen.

Of course, here is my disclaimer: I do not for even a second believe that any explosives were used in the 9/11 attacks.

I hope I'm being clear and that no one reading this thinks that I buy in to any truther nonsense.


According to NIST collapse of each tower was caused by the failure of one wall, so if you believe the official account you must be able to accept that explosives planted on every column on one wall would achieve the same result. I don't think any debunker here would refute your argument above.

But the OP is pointing out that Conspiracy Theorists cite numerous phenomena as evidence of explosives (in other words they claim since these things were observed, explosives must have been used). By direct logic, this means these observed phenomena must have been directly caused by explosives.

Thus the OP is discussing the amount of explosives that would be required to directly cause the observed phenomena, and not just that would be required to cause collapse.

Whether this amount is indeed "mind numbing" I do not know. As there are no sensory nerve endings located in the brain I would humbly suggest the mind is perpetually numb.

-Gumboot

[FactCheck]

Whether this amount is indeed "mind numbing" I do not know. As there are no sensory nerve endings located in the brain I would humbly suggest the mind is perpetually numb.

-Gumboot

I stand corrected. :P

[Hellbound]

Lets see what we have so far...

1) I'm going to say it is the pool size of the molten metal pool in Jones paper. (Yes, the concrete pancaked floors which he says is molten metal. That's all we have from the conspiracy story.

2) Approximately 150 kg TNT per floor cut. Lets say it was the top 70 stories for argument sake. That's 10,500 kg (23,140 lbs) of tnt. How much C4? Thermite?

C-4 has a relative force of 1.4, meaning a pound of C-4 is the equivalent of 1.4lbs of TNT. That gives you 7500kg of C-4 (16,500 lbs.), or a bit over 8 tons.

3) 2000 kg to through 20 to 30 stories of column trees 300 ft. (I know it was on another thread but the purpose for this thread is to add it all up.

4) To turn concrete into dust - no number yet

I figured a minimum number in one of the early, long threads that I believe is stickied now. I used military calculations for breaching charges on reinforced concrete, and assumed the breach diameter for breaching would be the puverization diameter for a C-4 charge. I also assumed that small charges were placed at small intervals inside the concrete, rather then few larger charges. Finally, I also used the diameter as the length of a cube, rather than a sphere. All of these assumptions made my calculations much less than what might actually be needed (if I erred, it's on the conservative side). IIRC, it came up in the 10's of thousands of tons of C-4.

On reflection this was part of the Christophera saga, but I don't recall exactly which thread it was in, and I'm too lazy to search now :)

5) To super heat air and create a pyroclastic flow - no number yet.


Looks mind numbing to me...

Yeah, once you start talking about blowing every floor and pulverizing all the conrete, the numbers start climbing at a very rapid rate.

[Dave Rogers]

According to NIST collapse of each tower was caused by the failure of one wall, so if you believe the official account you must be able to accept that explosives planted on every column on one wall would achieve the same result. I don't think any debunker here would refute your argument above.

Except that the explosives would have to reproduce the inward bowing and eventual inward collapse of the failing wall, which would be difficult at best. It's occurred to me recently that you could reproduce it by...

No, why should I give the truthers more ammunition? Work it out for yourselves, guys.

Dave

[FactCheck]

Except that the explosives would have to reproduce the inward bowing and eventual inward collapse of the failing wall, which would be difficult at best. It's occurred to me recently that you could reproduce it by...

No, why should I give the truthers more ammunition? Work it out for yourselves, guys.

Dave

That's the 'backhole in the core', silly...

[Myriad]

I would like to know if anyone could calculate how much explosives would be needed to
...
2) Cut the columns on all floors to remove resistance
...
Sounds like a mind numbing amount which makes hiding it laughable. Heh!


I've used the following argument when discussing claims that cd charges were used to "reduce the resistance" of the lower structure, to account for its rapid collapse.

Assume that all the resistance of the lower structure comes from the resistance of the columns to being fractured. (Obviously, once a piece of column has broken off, that piece no longer resists collapse.) Reduced resistance comes from cd charges, instead of collapse momenum, fracturing the columns. Keep in mind that apart from cd charges, a column fracture can only occur if that part of the column is "resisting collapse."

In the actual collapse, a certain number of column fractures occurred. This number can be estimated based on the average length of the column pieces, and the total number of columns (since one piece represents one fracture). There were about 113,000 meters of column in each tower, so if they broke into sections averaging 10 meters long, that's 11,300 fractures.

Now, the question becomes, how much was structure's "resistance" reduced by the alleged cd charges? If the claim is that it was "reduced to nothing" (so as to cause a "free fall" collapse), then each of the 11,300 fractures must have been accomplished by cd explosives. If the resistance was reduced by, say, only half, then 5,650 explosive charges were required. The size of the demolition charge required for each fracture would depend on the type and thickness of each section of each column and, for obvious reasons, are not widely published outside the industry, but based on estimates in the public press about the total amounts of explosive used in various known demolition projects, an average of one kilogram per fracture would be a reasonable estimate. So the total amount is about 11 tons times the fraction that's claimed that "the resistance was reduced." (Or, 1.1 tons for every 5 percentage points that "the resistance was reduced.")

Note that for all but very small amounts of reduced resistance, this also means thousands of charges that have to be connected by at least tends of kilometers of detonation cord or equipped with radio-controlled detonators -- if the latter, none of which can detonate prematurely due to stray radio signals, or fail to detonate and thereby risking discovery afterward.

If challenged on the initial assumption that only the columns contributed to the structures' "resistance," you can go ahead and add additional estimates for the explosives required to fracture the concrete into dust or whatever.

The useful thing about this calculation is that it ties a specific claim, that the resistance of the structure was reduced, to the amount of explosives that would have to have been used for the claim to be true.

Respectfully,
Myriad

[Hellbound]

The size of the demolition charge required for each fracture would depend on the type and thickness of each section of each column and, for obvious reasons, are not widely published outside the industry, but based on estimates in the public press about the total amounts of explosive used in various known demolition projects, an average of one kilogram per fracture would be a reasonable estimate.

Ah, probably not. Maybe if you had direct access to each location on the steel beam, and you could shape the charges, and you could drill the beam to place the charges inside the steel and/or column, rather than on the outside.

The steel on the lower columns was 6 inches thick, and only taperd to about 2 inches thick at the top IIRC.

Using military formulas for a cutting charge with C4 placed directly on the steel, it comes up to something on the order of 60 lbs. If you assume a shaped charge of some sort, you could half or possibly even quarter this. I'd be very hesitant to say that anything less than about 10lbs is going to cut one of those columns.

Remember, we can't just weaken the column enough to fail, it has to be cut compeltely so that it offers no resistence to the collapse.

[einsteen]

Einsteen:

Those videos are VERY interesting for sure, but I would be very careful about how to interpret them and not jump to conclusions.

P.S. Nice avatar!
Of course not Apollo20,

I found a better quality one and I hope OneWhiteEye can find some time to have a look at it. I'm of course absolutely not qualified to interpret videos but some observations do harm nobody. I've also seen people talking about the flashes in the 2nd video, but to me it looks like those flashes are due to broken glass reflecting in the sun, on the other video there is only one white dot visible, a compression artifact. Your vacuum no-sound joke was a good one!

Beachnut,

I know how measurements work and understand that when two measurements have an error, this error propagates in the end result, for the difference between two points the (absolute) error even doubles and the relative error grows also very much because we are measuring small objects. The height of a story got also an error, but that can be made very small if you take a lot of stories, the error then is still two pixels and can be divided. But as I said before this is rough amateur work.

Fastcheck,

I think that is a very good one! I had 3 buckles per perimeter column in my mind but since those ## things come in 3 then it looks like a possible debunk. At some points it looks indeed that air is popping out from the windows. From an official story's point of view it then is a combination of this and air. But imho the ejections are very violent even in the beginning. This should be quantitized precisely of course. If you note that a 8m-12m object is ejected with more than 10m/s while there is barely motion then I'm wondering if released strain energy can account for that.

1337m4n,

Good link, I'm fully aware of the problems you run into to get a consistent model, bypassing tower security etc. Absolutely very relevant questions.

[WildCat]

And the next one is even more laughable. The columns can clearly be seen getting pulled in before the so called "Squibs"/explosions, what ever... Heh!
That's because no explosives were used - the secret cabal used implosives! When they go off everything gets sucked into a mini black hole, and they are silent!

[Gravy]

Er, einsteen, here's your biggest collapse "anomaly"

There were no detonations!
D'oh!

[FactCheck]

What I have so far, after converting some of the answers is a whopping 1,620 tons! About how many file cabinets is that?

That doesn't include all the steel sections which landed 300 ft away.

Near free fall – remove resistance - 11.57 tons of tnt.
Molten pool for 6 months -Not added
Throw column sections 300 ft - 2.2 tons each event (only counted one event)
Pulverize concrete 622 tons of TNT
Pyroclastic flow 985 TONS of TNT
Total 1,620 tons

Darn! I forgot the dustfication of steel! HEHEHE!!!

[Myriad]

Ah, probably not. Maybe if you had direct access to each location on the steel beam, and you could shape the charges, and you could drill the beam to place the charges inside the steel and/or column, rather than on the outside.

The steel on the lower columns was 6 inches thick, and only taperd to about 2 inches thick at the top IIRC.

Using military formulas for a cutting charge with C4 placed directly on the steel, it comes up to something on the order of 60 lbs. If you assume a shaped charge of some sort, you could half or possibly even quarter this. I'd be very hesitant to say that anything less than about 10lbs is going to cut one of those columns.

Remember, we can't just weaken the column enough to fail, it has to be cut compeltely so that it offers no resistence to the collapse.


Thanks for that, Huntsman. I knew my estimate was way under for the core columns especially on lower floors. But the column count is dominated by the far more numerous, and less beefy, perimeter columns, so I thought it might average out reasonably (while still being a conservative estimate overall).

Actually, if you could give me an estimate of the amount to sever one perimeter column at about floor 55, that would be a good value to use as the average for all the perimeter column fractures. Or for all the columns, to keep the estimate conservative.

Respectfully,
Myriad

[Hellbound]

Ah, crap. I'll have to look for my earlier calculations, as I don't recall any of it now :) I was hoping to be lazy.

Give me a few days, and I'll find the steel thickness estimates I used before and see what I can come up with. I'll try to get an average for both the core columns and the perimeter columns (avergae thickness...just the median between the thickest and thinnest) and give the figures for an around-the-column cutting charge.

[FactCheck]

Can someone tell me how we are getting these numbers? Can someone do the calculations for each? I was considering putting the results on my site but I hate to put figures up without showing how they were calculated. I will give full credit to the author of course.

[Gravy]

You'll find calculations for concrete pulverization in the Bazant, Le, Greening, Benson paper, and for throwing a steel beam (not including the energy needed to separate it from its connection) in R. Mackey's Griffin paper.

[Dave Rogers]

What I have so far, after converting some of the answers is a whopping 1,620 tons! About how many file cabinets is that?


Typical NWO shill tactics, trying to play down the seriousness of the implications by saying that only 1,620 tons of explosives were used. Jim Hoffman calculated 2,500 tons per tower.

Really, there is no adequate way to satirise the truth movement.

Dave

[Hellbound]

Okay, I'm ready to give some preliminary numbers.

My sources:
http://www.fema.gov/pdf/library/fema403_apd_x.pdf
http://www.fema.gov/pdf/library/fema403_ch2.pdf
www.fema.gov/xls/rebuild/mat/apd_sprdsht.xls (http://www.fema.gov/xls/rebuild/mat/apd_sprdsht.xls)
http://wtc.nist.gov/pubs/NISTNCSTAR1-1A.pdf
U.S. Army FM 3-34.214 (FM 5-250), Explosives and Demolitions, July 2007...Chapter 3-II (Normal Cutting Charges) and Chapter 3-III (Special Cutting Charges) (have to be militayr to access, can be found at the usapa.us.army.mil site).

Now, I've only given a preliminary glance, so bear that in mind.

For the core columns, I've found that they ranged from box columns measuring 14" by 39" using 4" steel, to wide flange beams 12" by 10" using 5/8" steel.

For exterior columns, it appears they were always something by 13.5", with something being anywhere from 9" to 14". Thicknesses ranged from 1/4" to 1/2".

So, being a back-of-the-envelope kinda guy, I'll take my representative samples as:
Core: 13" by 20" box, 2" steel
Exterior: 13.5" by 11" box, 3/8" steel

Now, I'm going to make the following assumptions:
1) Direct access was gained to all four sides of the column in question.
2) There is no standoff distance (charges are placed directly onto the steel members, drywall, fireproofing, etc are removed).

Now. To the formulas.

The formula for a cutting charge is P (in pounds of TNT) = 3/8 A (cross-sectional area of the steel to be cut). This is for block charges. This gives us the following:

Box column sections:
Area of short sides = 13" by 2" = 26 square inches.
Area of long sides = 20" by 2" = 40 square inches.

So, that gives us an A of 132 square inches. Plug that into our formula and we get 49.5 lbs of TNT, or 35.36 lbs of C-4 for a block cutting charge per core column.
There were 44 to 47 core columns, so taking the small number that gives us 1,556 lbs of C-4 per floor for the core. I'd give this a +/- 50% or so, cause I've guestimated a bit :).

The exterior columns we have:
Area of long side = 13.5" by 3/8" = 5.0625 square inches.
Area of short side = 11" by 3/8" = 4.125 square inches.

This gives us an A of 18.375 square inches, and that results in 6.89 lbs of TNT, or 4.92 lbs of C4.
There were 59 exterior columns per flat face, giving 236 exterior columns, which will add another 1,160 lbs or so.

So, let's assume we shape the charges a bit.

Our only real option here is a ribbon charge. Diamond and saddle cahrges are for bars/beams up to 8 inches...everything here is larger.

I'm not going to get into the calculations here, but the riboon charge for the core would need to be 1" thick, 6" wide, and 66" long, which gives a volume of 396 cubic inches, or 6,489 cubic cm. The density of C-4 is 1.63 g/cubic cm, which gives us a weight of 10.58kg, which converts back to about 23 pounds per column. This formula already assumes C-4 rather than TNT (as it requires moldable explosives). With 44 columns, that's 1,012 lbs. of C-4.

For the exterior columns, we need ribbon charges 3/16" by 3/4" by 47", or 6.6 inches cubed (108 cubic cm), which converts through to about a quarter of a pound (.24). Not too much. That means we add another 56 pounds for the exterior columns.

You can see two things from this. Even a best case scenario need a bit over half a ton of C-4. Also, shaping charges makes the most difference on small, light targets and (relatively) little difference to two-inch thick steel.

Now, these are back-of-the-envelope calculations. I'd give these a very wide margin of error, and they are definately open to correction by anyone with more experience.

[Belz...]

Beachnut:

The lack of explosive sounds is easy!

The explosions created a vacuum (that sucked the building down at faster than free fall don't you know), and sound doesn't travel in a vacuum!

There's also no GRAVITY in a vaccum, as we all know.

[1337m4n]

Beachnut:

The lack of explosive sounds is easy!

The explosions created a vacuum (that sucked the building down at faster than free fall don't you know), and sound doesn't travel in a vacuum!

So, explosives INSIDE the building created a vacuum OUTSIDE the building so that none of the witnesses could hear anything?

[FactCheck]

So, explosives INSIDE the building created a vacuum OUTSIDE the building so that none of the witnesses could hear anything?

That explains it!!! It wasn't PNAC! It was PTMC!

http://en.wikipedia.org/wiki/Descent_3

They are the only ones with "BlackShark" technology!

FactCheck/Material Defender races to his Pyro-GL to save mankind!

[Myriad]

I'm not going to get into the calculations here, but the riboon charge for the core would need to be 1" thick, 6" wide, and 66" long, which gives a volume of 396 cubic inches, or 6,489 cubic cm. The density of C-4 is 1.63 g/cubic cm, which gives us a weight of 10.58kg, which converts back to about 23 pounds per column. This formula already assumes C-4 rather than TNT (as it requires moldable explosives). With 44 columns, that's 1,012 lbs. of C-4.

For the exterior columns, we need ribbon charges 3/16" by 3/4" by 47", or 6.6 inches cubed (108 cubic cm), which converts through to about a quarter of a pound (.24). Not too much. That means we add another 56 pounds for the exterior columns.

Thanks, Huntsman.

And that's to sever each column once. Clearly that's enough to cause the building to collapse (except perhaps on the top few floors). However, to cause a collapse in which the entire lower structure's "resistance to collapse" is reduced to zero, we have to use explosives to sever each column every 10 meters (that is, an explosive charge for every piece of every column, because). Otherwise they can only have been fractured by resisting the collapse forces. So, multiply that amount by 28 (North) or 34 (South) times the fraction by which resistance was supposedly reduced. (Or by 40, since the upper blocks' "resistance" should count too.)

That's about 30-40 tons per tower for eliminating all resistance. I was off by about a factor of 3 or 4, not bad for a wild-ass guess. (I was right that a kilogram per exterior column fracture is way more than enough, but didn't realize that the core columns would require charges so much larger that it wouldn't come close to averaging out.)

Respectfully,
Myriad

[Hellbound]

Myriad,

Yeah, I didn't realize the exterior columns would need so little, myself :)

But the thickness of the steel increases your charge exponentially, just as distance from the column does. It all starts to add up VERY quickly.

Also keep in mind that this assumes we're wrapping the explosive completely around the columns, something that would not be possible to do, for example, on the exterior columns in a discreet manner. If you're trying to cut through the entire box column from one side, those charge sizes will at least double.