The SINGLE MOST IMPORTANT ANALYSIS of the events of 9/11.

a reply to: loveguy

If I took four slabs of concrete, and dropped them from my hands at 5ft, I can guarantee there will be dust that will be emitted. If I took the same slabs and dropped them from the roof, there will be more dust. At thee WTC, you had 110 floors falling 1000ft+ with steel columns, trusses, and a ton of other heavy debris elements all falling together in an equivalent mega grinder. This is not including the fireproofing that is being dislodged and the sheetrock that was found on every floor that was also getting crushed and smashed.

I cannot believe that these points need to be re-explained again as to how that dust happened. People really need to get this garbage of explosives are the only way concrete makes dust and can only do damage to thing. Explosives are not the only answer!!!!!!!!!!!!!!!

a reply to: MALBOSIA

And where do you think those floors came from?? The debris pile itself was a few stories high. The floors were compressed by the force of collapse. Workers during clean up said it was like cutting into geologic strata with the layers so compressed tightly. This includes the concrete floor, steel pan decking, floor trusses, and other debris. You can read the accounts here, which I had posted years ago:
www.abovetopsecret.com...

Accounts links here:
www.historycommons.org...

Two weeks after 9/11, engineers Pablo Lopez and Andrew Pontecorvo are walking in the B2 basement level at the ruins of the World Trade Center, towards where the North Tower stood. They discover a “solid, rocklike mass where the basement levels of the tower had been,” and see “the recognizable traces of twenty floors, very much like geologic strata revealed by a road cut, compressed into a ten-foot vertical span. In one place, the steel decks of half a dozen floors protruded like tattered wallpaper, so close together that they were almost touching where they were bent downward at the edge. Nothing between the decks was recognizable except as a rocky, rusty mishmash. In a few places what might have been carbonized, compressed stacks of paper stuck out edgewise like graphite deposits.” As New York Times reporters James Glanz and Eric Lipton describe, Lopez and Pontecorvo have found “where the vanished floors [of the tower] had gone. They had not just fallen straight down. The forces had been so great and the floors so light that they had simply folded up like deflated balloons.”

At some later time, ironworker Danny Doyle, who is also working at Ground Zero, finds that floors of the South Tower have been compressed into a formation like what happened with the North Tower’s. He discovers “a distinct mound of debris set into the pile, about six feet high, with strands of wire and pieces of rebar sticking out. It looked like layers of sediment that had turned into rock and been lifted up on some mountainside.… Here were ten stories of the South Tower, compacted into an area of about six feet.”

All that debris didnt just get pulverized into dust. Most of it remained compressed in the piles.

originally posted by: GenRadek

All that debris didnt just get pulverized into dust. Most of it remained compressed in the piles.

That claim contradicts USACE debris expert.

Most of the concrete from the WTC site was pulverized into dust in the Sept. 11 attacks. But huge amounts of structural steel remained scattered in tangled heaps, says Allen Morse, USACE chief debris expert and FEMA technical advisor.

LINK

originally posted by: loveguy

originally posted by: wmd_2008
a reply to: MALBOSIA

First we are in DIFFERENT time zones I also have a LIFE away from ATS.

Look for DEBRIS FIELD images in Google, also do YOU honestly think all the dust is concrete, what about the sheetrock, sprayed on fire protection,vermiculite behind the cladding panels, smoke & soot from the fires, dust from uncleaned areas , paint even glass was found in the dust samples.

You see truther claims about the dust are the same as when they talk about the cause, the dust is just concrete it wasn't in the same way it wasn't just fires that caused the building collapse.

Concrete

Concrete

Concrete

For some strange reason YOU and others like you seem to think 4 and a half inches of floor grade concrete with some mesh through it should be indestructible even when it falls HUNDREDS of feet and thousands of tons of material falls on it.

The distance from one floor to the next level up/down remains the same +/- 14 feet? Concrete dustifies in 14 feet of freefall?

If you took the 4 and a half inch thick concrete floor slabs and neatly stacked then on top of each other with NO damage it would be just over 41 ft high, and you are silly enough to think slabs falling from more that 1000+ feet and the floors below being impacted by thousands of tons of material are only falling a floor HEIGHT

Also here is a list for YOU please read and retain THOUSANDS of SQ MTRS of sheetrock, THOUSANDS of CUBIC MTRS of sprayed on fire protection, the same for vermiculite behind the cladding panels, smoke & soot from the fires, paint, and a number of other things including paper & glass were all in the dust cloud NOT JUST CONCRETE.

YOU guy's really have a problem retaining for than one fact at a time, hence only concrete mentioned as dust, and only fires as a cause of the collapse.

originally posted by: wmd_2008

originally posted by: loveguy

originally posted by: wmd_2008
a reply to: MALBOSIA

First we are in DIFFERENT time zones I also have a LIFE away from ATS.

Look for DEBRIS FIELD images in Google, also do YOU honestly think all the dust is concrete, what about the sheetrock, sprayed on fire protection,vermiculite behind the cladding panels, smoke & soot from the fires, dust from uncleaned areas , paint even glass was found in the dust samples.

You see truther claims about the dust are the same as when they talk about the cause, the dust is just concrete it wasn't in the same way it wasn't just fires that caused the building collapse.

Concrete

Concrete

Concrete

For some strange reason YOU and others like you seem to think 4 and a half inches of floor grade concrete with some mesh through it should be indestructible even when it falls HUNDREDS of feet and thousands of tons of material falls on it.

The distance from one floor to the next level up/down remains the same +/- 14 feet? Concrete dustifies in 14 feet of freefall?

If you took the 4 and a half inch thick concrete floor slabs and neatly stacked then on top of each other with NO damage it would be just over 41 ft high, and you are silly enough to think slabs falling from more that 1000+ feet and the floors below being impacted by thousands of tons of material are only falling a floor HEIGHT

Also here is a list for YOU please read and retain THOUSANDS of SQ MTRS of sheetrock, THOUSANDS of CUBIC MTRS of sprayed on fire protection, the same for vermiculite behind the cladding panels, smoke & soot from the fires, paint, and a number of other things including paper & glass were all in the dust cloud NOT JUST CONCRETE.

YOU guy's really have a problem retaining for than one fact at a time, hence only concrete mentioned as dust, and only fires as a cause of the collapse.

You are the only one that has said the dust cloud was only concrete. Yes there was gypsum in there, not thousands of sq' metres, more like a million. There is thousands in a 3 story spec. house not the WTC.

There were a few different colours of dust being ejected from the building at the start of the collapse before it visibly became one colour. There was the black, which was the smoke, there was dark grey which was the concrete and fire spray and then there was a very light grey, which was likely the gypsum and other dust. Vermiculite?? Unless there was an office that hasn't been renovated since the mid '80's, the only place you would find that is in the base building, not the tenant spaces.

Why won't you accept that the concrete was pulverized to dust? USACE debris expert claims it was, but you have more information than Allen Morse?? Where did you get information that contradicts his?

a reply to: MALBOSIA

My mistake. I did not read his account about that part. However, i do not see the issue that is being brought up with the concrete. So what that it was pulverized? What exactly does this prove that is sinister? All it proves is that the concrete was destroyed during the collapse. If it was compressed to such an extant that multiples floors were squeezed to fractions of their original size, then what chance did the 4" of light concrete have to survive intact?

Why does the "Truth" Movement have to focus on such none issues and expand them into nonsense?

originally posted by: GenRadek
a reply to: MALBOSIA

My mistake. I did not read his account about that part. However, i do not see the issue that is being brought up with the concrete. So what that it was pulverized? What exactly does this prove that is sinister? All it proves is that the concrete was destroyed during the collapse. If it was compressed to such an extant that multiples floors were squeezed to fractions of their original size, then what chance did the 4" of light concrete have to survive intact?

Why does the "Truth" Movement have to focus on such none issues and expand them into nonsense?

Because pulverized concrete does not mesh with "progressive collapse" If floors trusses were being forced down on top of each other, the concrete would not be pulverized because the resistance of the structure is giving way floor by floor and quite easily by the account of OS pushers. So if the resistance is giving-way to the force of the top section above, what does the concrete have to be sandwiched between? The top has a lot of weight to it, yes, but the bottom is giving -way to it. So how did the concrete absorb enough energy to explode into dust if the energy is continuing down at least half free-fall speed? Maybe when it hit the deck it would finally absorb the full weight of the building slamming down on it but the victimization and ejection of the concrete started at the very start of the collapse.

a reply to: MALBOSIA

and thats where you go wrong. There was progressive collapse, which occurred AFTER the building started to collapse. Floors had only one way to go........ down. Workers discovered proof of this in the debris field. Did you not read the clean up worker's accounts I posted? Concrete would get pulverized because not only does it have 15-30 floors landing on top of it, but it has to go down and take out the rest of the structure. Each floor impacted added mass to the falling mass. Plenty of force to smash concrete to bits and also have the floors smashed together. it was not just one floor hitting another floor. Then another one floor hitting another. It was 15+ floors hitting one, then 16 hitting one, then 17 hitting one, then 18 hitting one, etc etc etc, till it gets to 80 hitting one and so on. Resistance in relation to the moving mass is getting smaller and smaller till it offers little resistance at all.

originally posted by: GenRadek
a reply to: MALBOSIA

and thats where you go wrong. There was progressive collapse, which occurred AFTER the building started to collapse. Floors had only one way to go........ down. Workers discovered proof of this in the debris field.

Is it not possible that some of that fuzed material was caused from the pressure of the weight and above 700 degrees that was recorded in the rubble weeks after the collapse? That wasn't loaded, I am curious.

Did you not read the clean up worker's accounts I posted? Concrete would get pulverized because not only does it have 15-30 floors landing on top of it,

Not by the progressive collapse theory it didn't, not till the bottom. 15-30 floors collected the concrete on the way down, adding more mass, progressively to each floor below, making the detachment of each truss and it's concrete slab, easier and easier on the way down.

but it has to go down and take out the rest of the structure. Each floor impacted added mass to the falling mass.

Those two sentences contradict one another. if it had to "go down and take out the rest of the structure, which I assume you mean pulverize the concrete slab, then each slab is NOT adding to the mass because it has been pulverized to dust and witnessed exiting the building.

Plenty of force to smash concrete to bits and also have the floors smashed together. it was not just one floor hitting another floor. Then another one floor hitting another. It was 15+ floors hitting one, then 16 hitting one, then 17 hitting one, then 18 hitting one, etc etc etc, till it gets to 80 hitting one and so on. Resistance in relation to the moving mass is getting smaller and smaller till it offers little resistance at all.

Until the top section hit the ground it wasn't "hitting" anything in order to maintain the speed of fall that it did. Apparently the iron wall angle clips and column braces were bending down and sheering before it could barely slow the collapse. I am sure you can agree that the weight of the building would bend 1/2" (or close to) iron before it crushed concrete to dust.

The OS NEEDS the concrete to stay in the building. Not only does it add to the weight of progressive collapse to allow the theoretical force to continue through continued resistance. But also because.... How did it turn to dust? The OS pushers are hogging the concrete for their theory and not allowing any other theory to address the concrete being pulverized and blowing out of the building like a fountain.

originally posted by: MALBOSIA

Not by the progressive collapse theory it didn't, not till the bottom. 15-30 floors collected the concrete on the way down, adding more mass, progressively to each floor below, making the detachment of each truss and it's concrete slab, easier and easier on the way down.

Another fine example of looking at one item in isolation and NOT what actually happened do you think it's just floor slabs that fell

Do you know when slab 99 hit slab 98 or when slab 56 hit slab 55 NO, no one does that's the problem with YOU and others with NO experience you look at the construction and collapse of these buildings in the most simplistic terms because that's all you can understand

originally posted by: lexyghot
There was very little, if any, column to column impacts. Not in the first half second, nor three seconds, nor at any time during the actual collapse initiation nor progression.

Therefore, this analysis is not a valid argument against the actual collapse times. At best, this can only be used as an argument against Bazant's limiting case analysis where he calculates that no matter what, the collapse progression was inevitable.

The facts are, that stuff fell on the floors, and the resistance from the floors and their connections were what was providing resistance to the collapse progression. You cannot deny this with any rational argument.

I could keep it short, or extensive. Short means : There was no pancaking.

Long means :

lexyghot : There was very little, if any, column to column impacts. Not in the first half second, nor three seconds, nor at any time during the actual collapse initiation nor progression.

You made no distinction between the kind of column. Thus you mean perimeter AND core columns. Thus you mean a pancaking collapse, solely by floors failing, then falling around the core, and inside the space between exterior and core columns, which theory NIST very early on already, excluded.

I even offered the evidence in this thread why the main reason/"evidence" for NIST to introduce their failing trusses theory/progressive collapse theory, was clearly wrong.
That NIST photo of what they thought was a sagging steel floor-truss behind a row of windows without glass in them, is in fact a sagging aluminum ceiling rim. The steel trusses under the composite floor, behind that row of open windows, were situated perpendicular to those broken windows at that floor.

Or you expect core column buckling being the cause of collapse initiation ? Which must be somewhere inside the damaged floors.
Explain then, where your proposed core column buckling started. And how.
Now that I proved NIST's sagging floor trusses - causing a progressive collapse - theory, to be bogus.

Thus, what really caused the perimeter columns-row to buckle about a meter inwards, minutes before collapse?

At a damaged floor, or above them? Note that you can see the first perimeter column packet suddenly hinging to the left (east) in the southwards filmed WTC-1N tower collapse videos. Above and beside a damaged floor impact hole.
During the collapse initiating event. A few minutes before, we saw a whole perimeter column row buckling more than a meter inwards. And that happened at a spot that was situated in front of a core column row at the perimeter of those core columns, indicating that this row of core columns was diagonally severed as the first ones, then fell a meter or so downwards and pulled the composite floor down with them, which caused the perimeter column row to buckle inwards.

Explain also the center of the hat truss failure in the first moment BEFORE collapse. Then after that, the sinking of the radio mast situated in that hat truss center, at the same moment.
Note where both structures were attached to. Thus, yes, the core columns must have failed FIRST.

Explain the symmetrical sinking of the roof lines and undamaged floors under that roof, as one block, directly after those two above events, without introducing failing core columns. Only using for your theory, the failing floors. Did they pancake?
Caused by a few buckling core columns? Or all of them? At the same time?

Or was the floor failure the initiating event?
Then the composite floor must have been still attached to all the perimeter columns in that row of them that showed that inwards buckling about a minute before collapse.
That composite floor must have been solely severed from the core columns, falling down beside the core on the next floor in your scenario.
And that pancake-scenario is proved wrong by NIST and Beck, see his next three excerpts after my replay of your same excerpt :

lexyghot : There was very little, if any, column to column impacts. Not in the first half second, nor three seconds, nor at any time during the actual collapse initiation nor progression.

He did not implicate that, he wrote that the yield strain (i.o.w. yield-point) of all core columns had to be calculated over the length of those core columns, in the height of the whole part of the building under the initiating event (which was the severing of those core columns), and not over the height of one floor.
""Page 11. 2. Rigidity assumption : ... Under compression they maintain their ultimate strength until the yield strain is reached. ...""

And thank you for so swiftly admitting exactly what Beck wrote already :

1. Page 10 : ... This means that in each building the collapse initiation and duration are consistent with the NIST (μ.ν) scenario being applied to the PerimeterColumns only, while the stronger core columns (CCs) are not present at all. (LT : in that NIST scenario. )

2. Fig. 4: ...As the core columns (CCs) are disabled (LT : thus not the floors! ), the collapse is opposed by the perimeter columns (PCs) mainly, as discussed in text.

3. V. Conclusion : ... On the other hand, we have demonstrated that the NIST scenarios are inconsistent with the structural parameters of the building. More precisely, the features of the avalanche propagation (initiation and duration) indicate that in their final moments the buildings did not have the core columns (CCs).

The north tower's final moments before their collapse. Severing these 51 core columns was the initiation event. Beck proved in his model calculations that all the remaining 25 core columns in his model could not buckle first. Thus they must have been severed laterally. The only force which could do that, is explosives.

In his model he let all the steel loose 50 % strength, and 50 % of all 236 perimeter and 51 core columns he declared as severed by a plane impact.
Read on pages 11 and 12 the rest of Beck's collapse-fitting model proposal, after : ""This said, let us propose a consistent hypothetical model of an avalanche. etcetera"".

originally posted by: wmd_2008
a reply to: LaBTop

WRONG !!!!!

""Larry Rivers was working in the basement of the building when the cave-in began. He said "We had about two seconds warning...a rumbling sound like Niagara Falls. I ran for my life. I looked back and saw four of my buddies being crushed by the concrete. It was sickening.""

Shoring from the top slab AFTER a concrete pour was removed early the slab dropped onto the next and the collapse continued to ground level then into the basement levels SOUND FAMILIAR!!!!

It's baiting, by not giving the link to the accompanying text but only to the picture.
I expected it, that's why I used words like "looks to me" and "possibly".

This is your pic's index page link : matdl.org...

Disclaimer: it is common to have honest differences of opinion about causes and responsibility for failures. The opinions expressed on this web site are those of the authors, and not necessarily those of the National Science Foundation, the American Society of Civil Engineers, the University of Alabama at Birmingham, or Cleveland State University.

You are comparing fresh apples with rotten apples, which will fall from the tree at the touch-down of a honeybee.
This firm had two major building failures in 5 years. Some fine builders they were.

www.thefullwiki.org...

originally posted by: MALBOSIA

originally posted by: GenRadek
a reply to: MALBOSIA

The concrete stayed mostly in place. It was only 4 inches thick on the floor pans.

You can see some of it here:

www.stevespak.com...
s662.photobucket.com...
1.bp.blogspot.com...

You forget that most of the concrete was in the foot print stacked up in the floor segments. A bunch was crushed in the collapses and ejected as dust, as one would expect, but a lot of the concrete stayed behind. The floor pans and floor trusses also stayed in the footprint. There is no way they were ejected. You can see them falling down during the collapse.

No, one would NOT expect the concrete to be pulverized to dust. and the only pic you posted of concrete in the actual debris on-site is in the basement under the the entire weight of the building, and what do you know... it wasn't turned to dust.

This is a big hole in the OS it seems since the pushers are trying so hard to make it trivial. You would think that that backbone to the progressive collapse would be more concrete. Pardon the pun.

Dammit, stop posting those Steve Spak pictures of TWO concrete layers in the FIFTH basement-floor !
It's pages ago already debunked !

MALBOSIA, I bolded your remark. Hope it gets through this time.

wmd_2008, this must interest you, I hope it will enlighten you at last.

www.thefullwiki.org...

Joe Taylor was operating a crane located on the 24th floor. Eyewitnesses said that the crane dropped floor by floor during a two to three minute period and finally toppled over as it hit the ground in a cloud of dust. He and another worker, Daniel Moquin, were rescued from the building by an Army helicopter from Ft. Belvoir after they sent down a note saying "For God's sake, please get us off of here." Taylor said "...Somebody hollered that the building was sinking in. I knew all that weight couldn't stay up there so I started to find a way to get down myself. But the stairs were blocked. There was a loud popping, cracking sound as the floors gave way one after the other."[6]
--snip--
Colin Povey, a senior at Wakefield High School in Arlington County, saw the crane fall.
"I heard a loud rumble and looked outside. The tower crane was at about a 45 degree angle and looked just like a knife slicing through the building. A cloud of dust rose up immediately afterward. I and a lot of other students went to the church lot across Virginia Route 7 immediately after school let out at 2:30 PM to see what was happening. Most of the students heard the crane collapse, but I was in one of the few rooms that had an unimpeded view of the tragedy.

I hope you understand that the crane severed all these floors in that gap in the building, except the top one which failed because of hasty work? During a two to three MINUTES period.! He heard the floors failing one by one, SLOWLY.
That's two external events that caused that building's PARTIAL failure.
And an indication how the three WTC towers should have behaved if those three demolitions were not such, but instead natural occurring collapses. Which they certainly were N O T.

Cause
Fairfax County hired Professor Ingvar Schoushoe of the University of Illinois, a concrete specialist, to investigate the cause of the collapse. He determined that the collapse occurred because of the premature removal of shoring from beneath newly poured floors.[10][11]

George Taylor, a workman for Northwest Sheet Metal, Inc., claimed that workmen were pulling concrete supports "out too damn fast. They're trying to hustle the job too damn fast."[2]

Thanks anyway, you just turned your so-called "floors pancaked" evidence, 180 degrees around, in favor of the O.S. Doubters camp.

You unintended gave me more strong evidence that an EXTERNAL force has to be added to the WTC collapses, to get to a reasonable explanation of their three initiation events :

E X P L O S I V E S (was that slow enough typing? )

Post Scriptum :

wmd_2008, I see someone (you? ) removed the link to that picture of the Skylines Towers collapse aftermath you posted.

However, I saved it (I learned, during those long years of 9/11 debates, the tactics used, in advance), thus, here it is :

files.abovetopsecret.com...

a reply to: LaBTop

No its your RUBBISH computer that's to blame nothing was removed.

On mobile will be back later.

a reply to: LaBTop


Wow, WMD is pretty upset.

I almost spit out my coffee when I read his last response.

a reply to: MALBOSIA

Not upset just having a dig at the fact that things only go missing on LaBTop's computer maybe it needing more coal

a reply to: LaBTop

Skyline Plaza is a large complex located in Bailey’s Crossroads, Virginia which includes eight apartment buildings, six office buildings, a hotel, and a shopping center. In the midst of construction on March 2, 1973, one apartment building (A-4) and the parking garage adjoining it collapsed.

The building collapsed while shoring was being removed from newly poured concrete between the 22nd and 23rd floors of the building and more concrete was being placed on the 24th floor. A climbing crane on the 24th floor fell to the ground in the collapse.[1][6][7] It was initially falsely assumed that the collapse was related to the fall of the crane

Two cranes were used to erect the building, one in section 2 and the other in section 4. At the beginning of construction, these cranes were supported on the 4'-0" thick mat foundation. As construction continued, both cranes were lifted in order to complete the upper levels of the building. On the day of the collapse, the base of the crane is section 2 was located on the 20th floor while the base of the crane is section four was located on the 14th floor. (Leyendecker 1977)

Important parts bold!
The crane did NOT slice through the floors, the collapse was initiated ABOVE the crane base.

originally posted by: GenRadek
a reply to: loveguy

If I took four slabs of concrete, and dropped them from my hands at 5ft, I can guarantee there will be dust that will be emitted. If I took the same slabs and dropped them from the roof, there will be more dust. At thee WTC, you had 110 floors falling 1000ft+ with steel columns, trusses, and a ton of other heavy debris elements all falling together in an equivalent mega grinder. This is not including the fireproofing that is being dislodged and the sheetrock that was found on every floor that was also getting crushed and smashed.

I cannot believe that these points need to be re-explained again as to how that dust happened. People really need to get this garbage of explosives are the only way concrete makes dust and can only do damage to thing. Explosives are not the only answer!!!!!!!!!!!!!!!

Ofcourse the little slabs will disintegrate if you dropped them from 10 feet, or 5 miles up...
Because what they come into contact with is structurally more sound, like the foundation meant to hold it in place?

The initial floor that was the first to fall--->fell 14 feet.

How it became dust during that process--->falling 14 feet is worth a video representation.
I'd also like to see some shredded floorpans not being ejected laterally.