Split Thread henryco's new paper

[henryco]

Actual physical movement of steel components is easily capable of causing destruction of significant parts of the building. If a massive object strikes the top of a steel column, and the column fractures at a lower point, the free lower end can do enormous damage to the structure at a point well below the lowest point that could have been reached at that time by free-falling debris at the upper end of the column. A point that seems to me so patently obvious that a failure to concede it constitutes wilful ignorance. If you hammer in a nail, does the tip of the nail wait till the time the hammer would have got there before it penetrates further into the wood?

Dave

I have never seen a nail keeping undeformed as the tower but instead projecting away part of its metal in such a situation!

 

[leftysergeant]

Once the Squibs are out of the building they cannot accelerate except if there is an extra source of energy acting there propelling them like a Rocket: if your observations are correct they are interesting from a conspirationist point of view

Serious "WELL, DUH!" There was a bazillion tons of crap falling into the HVAC system to keep driving the stuff.

But here you are only able to see a squib when it is out of the building where there is nothing to restrict the flow thus no way how it could accelerate anymore.

Please put down that gun and put your golashes on. Your are tracking big red blood spots on the carpet now. Look at the freaking video close-ups of those squibs. They grow bigger and stronger and more full of stuff (until they are as full as a twoofer's head with stuff) as collapse continues. Totally inconsistant with the behavior of explosive charges, as far as anybody with an IQ over 75 and experience with explosives will tell you.

Again neither is there such restricting paths inside the building on any floor at the WTC because these are open structures between the core and exterior columns: the compressed air getting in through an elevator shaft could flow everywhere and it would have no reason to run particularly along the ducts you mention.

The ducts open into every room on the floor. They are designed to carry over-pressurized air. Up or down don't matter. You are obviously unfamiliar with HVAC.

Moreover a piston effect needs hermiticity. What you call a piston here several floors above is just a sieve.

Bull flops. Air could not travel upwards through all that rubble.

On the other hand the ducts can stop all projected debris (by explosions) except the ones running in the direction of the ducts thus producing a very localized Squib.

Ermm...Whiskey Tango Foxtrot?

 

[Alferd_Packer]

mechanical floor

 

[leftysergeant]

pressure cannot carry by itself a great weight of rubble faster than gravity : neither can it carry air and dust.

Did you catch that, guys? Tornadoes cannot exist by the laws of nature.

 

[henryco]

Pretending that there weren't any collisions in the early stages of the collapse is a bit pointless. It's inevitable that structural components failed at many different points, and that there were many collisions between elements of the upper and lower parts of the structure that had not previously been in contact. If you don't understand this, you haven't the basic knowledge to even participate in this discussion.

Dave

Remember that this is exactly the scenario my article was excluding: a succession of collisions between falling pieces because it could not reach the level of the ejections intime!
Remember that YOU argued that a mechanical constraint could propagate instead. So i was just noticing that this is a collisionless scenario : all parts are already in contact from the begining in this case.
The problem is that obviously such kind of constraints would not produce the kind of destruction we see ahead of the genuine collapse front!

 

[DGM]

anymore.

Again neither is there such restricting paths inside the building on any floor at the WTC because these are open structures between the core and exterior columns: the compressed air getting in through an elevator shaft could flow everywhere and it would have no reason to run particularly along the ducts you mention.

.

Do you have a cite for this? I doubt this could be true due to fire codes. Great lengths are taken to stop air (fire) from traveling inside a building.

 

[henryco]

I was right, you do not appear to understand how high rise HVAC systems are designed.

Please explain the basics to me (or give me a good reference). Then i will have to stop this discussion. Not because your are not interesting contradictors but because it's hard to discuss with many people at the same time, especially in english for me!

 

[Alferd_Packer]

and later only when all the clean air has been evacuated should we start to see the flow of the dirty air: this would take much time since the column of clean air is huge, before seeing the dust!

The HVAC shaft in the core was only a fraction of the size of the entire floor. the dust generated by the collpase of the first floors would have rapidly filled that shaft down to the intake. sure the overpressure would have been stored on the lower floors, but the relief for that pressure was out the HVAC system.

 

[henryco]

Do you have a cite for this? I doubt this could be true due to fire codes. Great lengths are taken to stop air (fire) from travailing inside a building.

In the Nist report you have the maps for all floors impacted by the planes and also lobby floors somewhere, i dont remember exactly where but you can also see here a typical floor:
http://www.darksideofgravity.com/WTC_init.pdf

slide 7 and 8

F H-C

 

[Sam.I.Am]

The problem is that obviously such kind of constraints would not produce the kind of destruction we see ahead of the genuine collapse front!

You aren't seeing "destruction" from the "Squibs" You are seeing air and debris being ejected through some pretty large exhaust/intake vents on the mechanical floors. The main supply and return plenums (and there were several of them leading down into the mechanical floors) aren't the size of home heating ducts. They were all several feet across and had a direct shot into the mechanical floors. If anything they were a better air conduit than the elevator shafts because the shafts had closed doors preventing the air from entering the shafts from the office spaces except from the top where the collapse front was.

 

[DGM]

In the Nist report you have the maps for all floors impacted by the planes and also lobby floors somewhere, i dont remember exactly where but you can also see here a typical floor:
http://www.darksideofgravity.com/WTC_init.pdf

slide 7 and 8

F H-C

NIST does not say (or document) that the core is open to the exterior (or any other part) of the building. In fact they show that the core is sealed off from the rest of the building by 2 layers of 5/8" dry wall. I'll try to find this for you later if I get a chance. The core being open like you describe would be against every fire code I'm aware off.

 

[henryco]

The HVAC shaft in the core was only a fraction of the size of the entire floor. the dust generated by the collpase of the first floors would have rapidly filled that shaft down to the intake. sure the overpressure would have been stored on the lower floors, but the relief for that pressure was out the HVAC system.

filled as rapidly as free fall ? the ejections on the video are at the same level as that of falling debris outside! yet the debris or dust had to propagate 30 more meters from the core to exterior colums in the same time!
Again pressure can only carry material particles and air when there are openings to let the flow escape out of the building : this is not the case until a window is broken.
And when the window is indeed broken you first have to eject a huge column of clean air before the dusty one can get out!

 

[Alferd_Packer]

Please explain the basics to me (or give me a good reference). Then i will have to stop this discussion. Not because your are not interesting contradictors but because it's hard to discuss with many people at the same time, especially in english for me!

A high rise building such as the WTC towers will have several mechanical floors (also called “technical floors”) evenly spaced through out its height.

On this floor you will have several different fan systems each serving a different zone of the building. The main ones are the supply and exhaust fans.

A supply fan system will have an opening to the outside, the intake, a large sheet metal box that contains the blower unit and the coils for heating or cooling the air. Air is drawn in through the intakes, past a filter bank and across the coils. The blower pushes the air to a central core shaft. The shaft is an open plenum which extends up past all the floors served by the supply fan. At each floor, there is an opening to the shaft that is connected to the sheet metal ducts on the floor. (think of it like a manifold) The supply air goes out to the floor via ducts, into the space.

In the ceilings of the spaces are open grills that allow the return air to flow through the open ceiling space to the return air shaft which is different from the supply air shaft. Back down on the mechanical floor, the return air is handled by the exhaust air system. Some of the return air is diverted back into the supply air system and some of it is exhausted out the building (usually at a location away from the supply air intake.

The key concept here is that all the floors are served by common air shafts in the core. As the floors collapsed, the over pressure, with the dust would have been forced back down the shafts to the intake and exhaust openings in the side of the building. It would not have circulated through the spaces below but would have been forced straight out through the air handling system.

 

[Seymour Butz]

These explosions are destroying part of the core of the tower in advance. this is just as in controlled demolition except that these "squibs" are here much more powerful and the ejecta much more massive: i measured 160km/h : trully explosive...I see no evidence that there are not also columns being ejected inside the cloud.but may be these are just mistimed.

Yeah, they'd have to VERY massive, since there was no preweakening.

Hushabooms strike again, eh?

Delsuional tripe.

Another front of much morepowerfull explosions follows.

And yet, these aren't seen to disturb the dust cloud at all.

 

[henryco]

Bull flops. Air could not travel upwards through all that rubble.

At any given time the collapse front is destroying a floor, thus all windows at this floor. so why the air should travel downward it it can escape throuh all these destroyed windows?

 

[Sam.I.Am]

NIST does not say (or document) that the core is open to the exterior (or any other part) of the building. In fact they show that the core is sealed off from the rest of the building by 2 layers of 5/8" dry wall. I'll try to find this for you later if I get a chance. The core being open like you describe would be against every fire code I'm aware off.

If you look at the core plans (hey those guys are good for something after all!) they show that the core was mostly divided into four sections on the office floors with corridors between them. Elevators and stairwells took up a lot of the space with the ventilation plenums taking up a lot of them as well. Restrooms, closets, electrical closets and mail rooms took up the rest.

 

[Alferd_Packer]

If you look at the core plans (hey those guys are good for something after all!) they show that the core was mostly divided into four sections on the office floors with corridors between them. Elevators and stairwells took up a lot of the space with the ventilation plenums taking up a lot of them as well. Restrooms, closets, electrical closets and mail rooms took up the rest.

there wopuld have been fire dampers at the junction of the floor ducts with the core shafts. Fire dampers are basicly steel shuuters held open by a "fusable link.' i.e. a piece of metal with a low melting point, like a sprinkler head valve.

 

[leftysergeant]

At any given time the collapse front is destroying a floor, thus all windows at this floor. so why the air should travel downward it it can escape throuh all these destroyed windows?

DUH! There was too much falling rubble in the way.

 

[Alferd_Packer]

At any given time the collapse front is destroying a floor, thus all windows at this floor. so why the air should travel downward it it can escape throuh all these destroyed windows?

it is more likely that the top of the building and the demo debris wedged inside of the exterior walls, acting like a piston in a sleave.

Did you know that 16 people who were inside WTC 1 when it collapsed survived?

they were located in stariwell B of the core.

the following is a statement from one of the survivors.

A Port Authority captain yelled at Lim to get moving, but he said, “You go ahead,” and he, too, put an arm around Harris, helping to carry her to the fourth floor.

That was when the wind started, even before the noise. “No one realizes about the wind,” says Komorowski.

The building was pancaking down from the top and, in the process, blasting air down the stairwell. The wind lifted Komorowski off his feet. “I was taking a staircase at a time,” he says, “It was a combination of me running and getting blown down.” Lim says Komorowski flew over him. Eight seconds later—that’s how long it took the building to come down—Komorowski landed three floors lower, in standing position, buried to his knees in pulverized Sheetrock and cement.

http://nymag.com/nymetro/news/sept11/2003/n_9189/

the funny thing is, not one of them mentioned feeling those massive high explosive detonations you claim happened.

 

[henryco]

A high rise building such as the WTC towers will have several mechanical floors (also called “technical floors”) evenly spaced through out its height.

On this floor you will have several different fan systems each serving a different zone of the building. The main ones are the supply and exhaust fans.

A supply fan system will have an opening to the outside, the intake, a large sheet metal box that contains the blower unit and the coils for heating or cooling the air. Air is drawn in through the intakes, past a filter bank and across the coils. The blower pushes the air to a central core shaft. The shaft is an open plenum which extends up past all the floors served by the supply fan. At each floor, there is an opening to the shaft that is connected to the sheet metal ducts on the floor. (think of it like a manifold) The supply air goes out to the floor via ducts, into the space.

In the ceilings of the spaces are open grills that allow the return air to flow through the open ceiling space to the return air shaft which is different from the supply air shaft. Back down on the mechanical floor, the return air is handled by the exhaust air system. Some of the return air is diverted back into the supply air system and some of it is exhausted out the building (usually at a location away from the supply air intake.

The key concept here is that all the floors are served by common air shafts in the core. As the floors collapsed, the over pressure, with the dust would have been forced back down the shafts to the intake and exhaust openings in the side of the building. It would not have circulated through the spaces below but would have been forced straight out through the air handling system.

Than you!
Do you know where could i find the locations of the intake and exhaust openings on the towers ? Is it documented in the Nist report?
The ejections i was discussing in the article are huge ones and propagate down the facade ejecting material at all floors not specific ones.
Also in case of the more localized "squibs" why do we see also a localized ejection in time and not a continuous or repetitive ejections of dusty air if these openings are the correct explanation ?
Again there are much more importants opening at the level of the destroyed floor at any time, so shouldnt the air escape in priority through them ?
And again at last : you still have an important column of clean air to evacuate before the dusty one.
Sorry but for all these reasons and others mentionned earlier i find it hard to believe that this could be the correct explanation...

F