jonesthecurl wrote:I also remember the same doubt being raised at the time, and an account in Private Eye (I think) suggesting that the reason for the collapse was the difference between the specifications for the buildings and the actual construction - i.e. skimping in construction leading to weakness which made it easier for the buildings to collapse.
I don't believe in the conspiracy theory of deliberate sabotage by the powers-that -be, though I wouldn't contend that it is completely impossible (any more than I can disprove the existence of God) - but the idea that the carnage was exponentially increased due to shoddy construction (very possibly involving corruption and some point in the building/ safety inspection/ whatever process) would not even raise one of my eyebrows. NY crane safety inspections anyone?
Now I said at the start that this would make more seese than fire bringing down the buildings. And certainly there has been little mention of shoddy construction. The company that built the towers has been pretty vocal that their structure would hold. Even to the point of people losing there jobs. Furthermore, the cheif construction manager died in one of the towers; he did not attempt to flee. So certainly he could not predict collapse. And that's a big deal when we are discussing shoddy construction.
hecter wrote:Well, ya... If the entire floors worth of supports have failed, separated, that means that you've got a good 15 floors worth of building on top of the supports below the failure point. Each suport has to support x amount of weight and there's four supports, that's well over 60x of weight crashing down on top of the floor below the failure point, causing a chain reaction of failures until you have a pancaked building. And just because a building is leaning doesn't mean it can't fall inwards...
What you are forgetting, is that the idea of a tower collapsing inwards, and pancaking, freefall spped acheived through the path of resistance, are brand new theories that have come of necessity. To accept these theries it total you have to ignore a volume of information, just like NIST does.
Again, taking your scenario, the tower was leaning 20 degress. The weight of the tower caused the joints on the supports ON THE OTHER SIDE to give away. So the tower collapsed inwards, destroying the INTACT support structure underneath it. Once a collapse starts anywhere (from three beams) total collapse is inevitable. You're presuming that any local collapse on any tower will automatically lead to global collapse. Again, at face value alone, it seems flawed. Yet with a controlled demolition, all the pieces do fit. The only questions remaining are how & why.
In fact, NIST does not go into any detail about the structural behaviors of the building once collapse had begun. Or freefall speed.
NIST's Theory
Remaining strictly within the confines of the officially prescribed theory, NIST crafts an explanation for the "initiation of the collapse of each Tower" that avoids faulting the Towers' construction: The aircraft impacts dislodged insulation from the steel, and the exposed steel succumbed to the fires. Sagging trusses pulled in portions of the perimeter walls, causing a rapid spread of "column instability" in perimeter columns, which in turned strained the fire-weakened core columns. The "tremendous energy" of the floors above the collapse zone led to "global collapse."
NIST's also continuosly talks about "Progressive Collapse" as if it is an accepted idea. They are completely ignoreing the histories of steel framed buildings reguarding total collapse, not to mention witness testimonies. The towers are their only examples; even NIST's own models failed to collapse.
NIST has never evidenced that the fireproofing was ever dislodged. It just sounds good to them.
NIST has never evidence tha the sealed core was exposed to fire. Nor have they shown how a fire reaching a maximum of 650C could have weakened the core.
At any rate, this guy said what I'm saying.:
1) A jetliner collides with the Tower, punching a gaping hole and producing a giant fireball.
2) The jet fuel ignites fires on multiple floors, producing thick smoke and heating and possibly deforming some structures.
3) The Tower collapses totally, from top to bottom, leaving virtually no recognizable pieces except fragments of its steel skeleton and aluminum cladding.
Each event was horrific and killed hundreds of people. But only the third event violated engineering experience and required the invention of new theories to explain. Yet the Report looks only at the first two events -- the subject of hundreds of pages -- while showing no interest in the third. These are curious priorities for an investigation that purports to explain the three largest and least expected failures of engineered steel structures in world history: the total collapses of WTC 1, 2, and 7.
Selling Progressive Collapse
The Report mentions "progressive collapse" 16 times, mostly in sections describing recommendations. It defines progressive collapse as when "a building or portion of a building collapses due to disproportionate spread of an initial local failure" but does not mention how rare the phenomenon is or that there are no examples of total progressive collapse of steel-framed buildings outside of 9/11/01.
By repeatedly invoking the specter of "progressive collapse" while concealing the phenomenon's lack of repeatability outside of "terrorist incidents," the Report surreptitiously bolsters its supposition that "global collapse" automatically follows from "collapse initiation."
It should also be noted again that for NISTs theory to even work, you have to have fire temperatures that were greater than the actual fires in the buildings.
6.14.2 Results of Global Analysis of WTC 1
...
The inward bowing of the south wall caused failure of exterior column splices and spandrels, and these columns became unstable. The instability spread horizontally across the entire south face. The south wall, now unable to bear its gravity loads, redistributed these loads to the thermally weakened core through the hat truss and to the east and west walls through the spandrels.
Not only has NIST failed to ever evidence that the core was thermally weakened, the core was basically fireproof.
The building section above the impact zone began tilting to the south as the columns on the east and west walls rapidly became unable to carry the increased loads. This further increased the gravity loads on the core columns. Once the upper building section began to move downwards, the weakened structure in the impact and fire zone was not able to absorb the tremendous energy of the falling building section and global collapse ensued. (p 144-5/194-5)
Again, this sounds good, but has not only never happened before, but NIST also is making assumptions here.
The building section above the impact zone began tilting to the east and south as column instability progressed rapidly from the east wall along the adjacent north and south walls, and increased the gravity load on the weakened east core columns. As with WTC 1, once the upper building section began to move downwards, the weakened structure in the impact and fire zone was not able to absorb the tremendous energy of the falling building section and global collapse ensued. (p 145-6/195-6)
No calculations as to how much energy. NIST does provide diagrams, but no calculations.
It is very significant that the Report does not display any images of its multifloor global model or its global model actually showing the "building section above the impact zone" beginning to tilt or beginning to move downward. There are a number of illustrations of its multifloor global model such as to the right, but none show "column instability", tilting, or downward movement.
Again, probably because NIST's own models failed to collapse....
Why the World Trade Center Tower's floors could not 'pancake' collapse as we have been told.
The typical floor structural configuration for the World Trade Center Towers spanned from the exterior wall columns to where the inner columns and a welded cage of steel formed support for the elevator shafts, stair towers, air shafts and mechanical systems, as well as, transferring floor and roof loads to the reinforced concrete foundation/footing structure sitting on bedrock some 70' below grade. Leasable floor areas typically terminated at the service core, where individual floor sections began again according to the floor plan layout. Yes, the individual floors acted as a unified structural 'diaphragm' to stiffen the structure laterally, but the steel composition of each floor was constructed in smaller units of open web trusses spanning between steel reinforced concrete�beams and topped with a steel deck and lightweight concrete. Thus, each floor was NOT a monolithic slab and structural system spanning across each tower from one exterior wall to the other three, as we are led to believe.
Each floor, in fact, terminating at the contiguous inner structural service core, resembled a square 'donut', with the core area being the 'donut hole', so to speak. Failure of floor structural support in any quadrant of the building plan, or even in any half, thus, would have failed asymmetrically. And at the time of failure would not, could not, have 'pancaked' symmetrically as the misleading NIST and commission reports indicate (diagrams shown in these reports are graphically out of scale, and do not accurately represent the building's massive, in fact, over designed, internal structure).
Original WTC Construction Drawings: http://911research.wtc7.net/wtc/evidenc ... table.html
Floor Plan, 35th to 40th Floors, http://911research.wtc7.net/wtc/evidenc ... A-58_0.png
Building Sections http://911research.wtc7.net/wtc/evidenc ... -177_0.png
How do I know this? What is my personal technical reference? From 1970 to 1972 I was a young design development draftsman for the firm of Minoru Yamasaki Associates, the design architectural firm for the WTC. I was part of the team that detailed the complex aluminum cladding fenestration details for similar building and also worked, in part, on detailing the WTC Executive Floor interior paneling and updating the WTC plans to reflect various 'as-built' construction changes. Based on actual project experience, I was, and am, quite familiar with the structural system at work on the towers, both at a technical and intuitive level.
From many videos it is clear that the initial devastating floor overloading was uneven, and then, suddenly, floor by floor, the destruction became uniform as the buildings seemingly demolished themselves. I would have expected a random destructive overload to cause only a portion of the building floors to fail at a time. This did not happen. The failure, thus, appears controlled and suspicious.
For the floors to 'pancake' uniformly, the first floor to fail would require all perimeter connections to fail almost simultaneously on each floor. The towers could not possibly have collapsed in this way as we have been told in the official reports. One floor, coincident, on top of another to start a demolition-like sequence, without powerful external forces at work, forces other than the plane crash--and the relatively low temperature jet fuel fires which burned away quickly--would not lead to a symmetrical, uniform collapse of all the floors. What other external forces could there be? Explosives? It is my view, knowing what I know, that the WTC towers were intentionally demolished.
R H Nigl July 18, 2008
rhnigl@exoptica.com
N.B. Where are the structural drawings? They still have not surfaced available for public review. I know they are available, there must be many copies in archives. Certainly the Port Authority, the City of New York, the architects and the steel shop fabricator's have copies.
And again, for NISTS theories to be right, they ignore testimonies from over 250 people. Firemen saw bodies in tower 7, firemen and witnesses saw bombs, firemen and civilians were hit with bombs, seismegraphs recorded mysterious explosions, mysterious explosions are on film matching the squibbs. And this is still just WTC, the Pentagon and Shanksville crashes are full of holes too.
hecter wrote:Conduction is exactly what's happening. Metals in general are a fantastic heat sink (you've got one in your computer, open it up and look, you should have a fan over a big hunk of metal) so any fires still burning afterwards, which there seemed to be, would have put a lot of their heat into the surrounding metal, oxidizing, possibly melting steel (keep in mind, this is after collapse) and melting other metals like aluminum.
I still don't see how you can have pockets of heat 1300 degrees days later, from a fire that was burning at 650C at it's hottest? Not only are you missing a lot of energy and heat, how hot was it to begin with that days later it's still hotter than the fire that brough the towers down?
hecter wrote:You said it yourself, nobody actually tested the metals. How do you know it was steel?
lol, NIST and FEMA never tested the metels...
Molten steel was found by metallurgical examination of WTC dust, by the U. S. Geological Survey, the RJ Lee Co. and physics professor Steven Jones. All of the official reports agree that a building fire, even one ignited by jet fuel, cannot attain air temperatures higher than about 1,800 degrees. Steel melts at 2,800 degrees.
There is also the now-famous video of molten steel flowing from a window in the South Tower.

There is also this image ofa flash of WHITE flame from the 81st floor of the South Tower.
For Backglass:
Here is what he wrote to me today at 10:38 PST:
Mr. Bryan:
I didn't personally see molten steel at the World Trade Center site. It was reported to me by contractors we had been working with. Molten steel was encountered primarily during excavation of debris around the South Tower when large hydraulic excavators were digging trenches 2 to 4 meters deep into the compacted/burning debris pile. There are both video tape and still photos of the molten steel being "dipped" out by the buckets of excavators. I'm not sure where you can get a copy.
Sorry I cannot provide personal confirmation.
Regards,
==========================
Mark Loizeaux, President
CONTROLLED DEMOLITION, INC.
2737 Merryman's Mill Road
Phoenix, Maryland USA 21131
Tel: 1-410-667-6610
Fax: 1-410-667-6624
http://www.controlled-demolition.com
There’s another complication in terms of the WTC debris temperatures, according to NASA analyses made on September 16th and 23rd.
Initial analysis of these data revealed a number of thermal hot spots on September 16 in the region where the buildings collapsed 5 days earlier. Analysis of the data indicates temperatures greater than 800 degrees F. Over 3 dozen hot spots appear in the core zone. By September 23, only 4, or possibly 5, hot spots are apparent, with temperatures cooler than those on September 16.
http://pubs.usgs.gov/of/2001/ofr-01-040 ... -0405.html
Over 800 degrees F is hot, but not nearly hot enough. A more speculative view on the paper suggests maximum temperatures of 1341 degrees F ( http://pubs.usgs.gov/of/2001/ofr-01-042 ... l.r09.html ), but that's still well below the “about 2,800° Fahrenheit” we need to get "literally molten steel".
The get-out here is that NASA could only see surface temperatures, obviously. And they took their first measurements on the 16th, so temperatures could have been even higher before then. Keep in mind that the hotspots had reduced significantly by the 23rd, though, and excavators wouldn’t have been digging anywhere close to the basement levels until some time after that.
Thomas A. Cahill, a retired professor of physics and atmospheric science at the University of California, Davis, "when they would pull out a steel beam, the lower part would be glowing dull red, which indicates a temperature on the order of 500 to 600 °C. And we know that people were turning over pieces of concrete in December that would flash into fire--which requires about 300 °C. So the surface of the pile cooled rather rapidly, but the bulk of the pile stayed hot all the way to December."
http://pubs.acs.org/cen/NCW/8142aerosols.html