Response Letter to the Boston Globe, "The Science of How Buildings Fall Down", 3 Dec 2007

I've written a letter to the editor, Boston Globe, in response to the article which appeared there yesterday:

I invite feedback as I plan to send this letter to the Globe later today. I wish to address some important 9/11 points, and call attention to the Boston Tea Party conference next week. The letter will also be sent to the author of the article (Colin Nickerson of the Boston Globe).

Dear Editor:
As reported in the Boston Globe 12/3/2007, a 1/8th scale building was constructed and subjected to the destruction of one of the key support columns. And what happened? The scale building did NOT fall down! I wish to contrast this empirical result with the COMPLETE destruction of the World Trade Center skyscrapers on 9/11/2001. From the article:

"As the column shattered at the base of the scale model structure in the basement lab, the downward force of the 5,000-pound load - metal weights simulating a real-life building's burden of walls, floors, and contents - shifted instantly, invisibly, to other beams and columns…. But the mock building held."

This experiment provides further reason to doubt the “official story” that gravity alone was enough to cause complete and rapid destruction of the WTC Towers and WTC 7. WTC 7, a 47-story skyscraper, was not even hit by a plane, yet it completely collapsed on the afternoon of 9/11/2001. This experiment confirms our argument that buildings are designed to stand, not give up and fall down completely even if a key support column is destroyed in an instant (see technical articles in the

On the other hand, we have all seen controlled demolitions using explosives in which tall buildings are brought straight down – completely and quickly. Of course, such a process leaves behind tell-tale residues. I will discuss the residues our team of investigators has in fact discovered in the WTC dust, at Faneuil Hall on Dec. 15, 2007. (See

Dr. Steven E. Jones
Professor of Physics (ret.)

There needs to be courses in collapse forensics

I would imagine that many of the professors who were cited in the Globe article are unaware of the controversy surrounding how the Twin Towers actually collapsed.

I think the real need is for education in structural forensics so that people become aware that building collapses are very rare and that if they do happen the cause can be determined and it can be ascertained as to whether or not there was criminal activity involved.

Dr. Jones, your letter sounds appropriate and it is good that you did not let this pass. In fact, it was an amazingly opportune article in that it provided you with a way to announce your upcoming presentation in support of the 2007 Boston 911 Truth Party and Conference. I hope that some of the Boston area professors and students, who were involved with this experiment, will attend the Conference to hear the presentations from yourself, Richard Gage, Joel Hirschorn, and Kevin Ryan.

A course in structural failure?

Mr Szamboti,

I greatly admire your work I've passed your paper on to many people and that of Dr. Jones. Here is a British University course for engineers in "Engineering/Failure Mechanics/Structural Integrity" which costs approx $750.

It's a correspondance course, so anyone with an engineering background can register for it, the problem is the case studies aren't of the WTC collapse, probably too controversial.

Structural integrity: designing against failure

Structural integrity is the study of the safe design and assessment of components and structures under load, and has become increasingly important in engineering design. It integrates aspects of stress analysis, materials behaviour and the mechanics of failure into the engineering design process.

The course is well-illustrated with case studies, and will be of interest to anyone associated with the design of any component or structure that experiences loading, and will be of benefit in developing skills in the analysis and assessment of product design.

It has universal applicability in the UK and across international boundaries.

Here's a course from the same University, again correspondance in Forensic engineering, it's a bit more expensive at around $2100

Forensic engineering

Why do products fail? Inadequate materials, poor manufacturing or assembly methods, bad design – failure can arise at any stage during product development, giving designers clues as to what failed and why, and how to avoid future failures. Using real case studies, you will examine the principles of good product design and assess the significance of poor design on the development process. You will work with techniques for analysing product failure, including scientific and engineering tests and observation. You will investigate real catastrophic failures – the Challenger space shuttle, the Hindenburg and the Tay Bridge – and consider the role of design, manufacturing, materials and communications in these fatal disasters.

It was just a passing thought for anyone with an engineering/science background who would consider furthering their knowledge and getting something down on paper to that effect.

Good information

Sherlock, thanks for sharing this type of information. I have had this type of training and also have learned from mistakes of my own and others over the years. One needs to know the mechanisms which cause failures in structures in order to design against them.

In my work in aerospace we do shock, vibration, thermal, moisture, and corrosion qualification testing on structures and components which weeds out design flaws before the design is used in service.

In the case of building design qualification testing is not feasible and that is why building codes and manuals like the AISC manual exist. These codes and manuals are a result of failure experience. Even so, smaller things like representative welds are qualified.

The interesting thing in the test, which is the subject of the Globe article, is that many of those who witnessed it would not have guessed that the loss of that column would not result in the destruction of the scale building. The professor who set up the test may have and was just trying to prove the point of load redistribution in a redundant structure.

Keep the pressure on Prof

Keep the pressure on Prof Jones. The facts are on our side. thank you

Science is all about the ability to predict.

This is what science is all about, experiments resulting in the ability to predict.

Thank you once again ... Prof Jones.


This sounds like an opportunity for Bill Nye, the science guy, to create a facsimile building, to scale, and present the logic of it all. In a full-scale television production.
The too fast falling reality of that day gives it all away. Gravity induced or not, the time sequence must be longer, to account for the 'burning' and 'crumbling' which accompanies firesome conflagrations.
Good luck with the presentations.

Letters to the Editor

We all need to write more letters to the editor. Thanks for posting this Steven. Good response and motivation. I hope it and others get published.

Don't sue me bro.

Would it be beneficial to point out that, because we live in such a litigious society, every structure that is designed to carry humans needs to be constructed to support multiple times the maximum rated weight????

Good point.

Twin Towers (& WTC7?), for the sake of the human safety, was not only an award winning, mass copied/produced tube-in-a-tube super-structure, designed to take on the gods, but was overdesigned by 2000% or 20x. How is that? Now, the question is 'Was a dirty burn the achilles hill of this design?". WTC93 explosion, 1975 fire, WTC5 fire in addition to other tall building fires speak to that. ;-/
Many hands make light work!
RRREMA=research, realize, react, educate, motivate, activate
"It's been said, and I think it's accurate, that my husband was obsessed by terrorism in general and al-Qaida in particular." (Hillary

WHOA, "2000% or 20x", Source?

This is a factual claim. Where is the source?

I have heard 3X, 5X, all sorts of claims, none of them consistent. Now it's "20x." This requires a factual sourcing, or a withdrawal, before hundreds of others start parroting it.


Source #1:

D9D by DRG (page # coming, book in car)

Source #2:

Richard Gage presentation or Ron Craig debate. I will be checking that out.

Source #3:

The structural analysis carried out by the firm of Worthington, Skilling, Helle & Jackson is the most complete and detailed of any ever made for any building structure. The preliminary calculations alone cover 1,200 pages and involve over 100 detailed drawings.

Because of its configuration, which is essentially that of a steel beam 209' deep, the towers are actually far less daring structurally than a conventional building such as the Empire State Building where the spine or braced area of the building is far smaller in relation to its height.

The building as designed is sixteen times stiffer than a conventional structure. The design concept is so sound that the structural engineer has been able to be ultra-conservative in his design without adversely affecting the economics of the structure

- Richard Roth, partner at Emery Roth & Sons, the architectural firm that was designing the Twin Towers ("City in the Sky", pages 134-136)

live loads on these [perimeter] columns can be increased more than 2000% before failure occurs.

- John Skilling, head structural engineer for the World Trade Center (Engineering News Record, 4/2/1964)
Many hands make light work!
RRREMA=research, realize, react, educate, motivate, activate
"It's been said, and I think it's accurate, that my husband was obsessed by terrorism in general and al-Qaida in particular." (Hillary

Beam vs. Column

FYI- Beams are horizontal, columns are vertical, terms that we should not interchange.



More on source #1:

D9D by DRG, page 149

"Even stronger statements can be found in reports in Engineering News-Record in 1964. Explaining that 'the World Trade Center towers would have an inherent capacity to resist unforseen calamities,' these reports said that 'live loads on these [perimeter] columns can be increased more than 2000% before failure occurs' and that 'one could cut away all the 1st story columns on one side of the building, and part way from the corners of the perpendicular sides, and the building could still withstand design live loads and a 100-mph wind force from any direction.'

note on source:
See "Structures Can Be Beautiful: World's Tallest Buildings Pose Esthetic and Structural Challenge to John Skilling" and "How Columns Will Be Designed for 110-Story Buildings," Engineering News-Record 2 April 1964; these statements are quoted in Kevin Ryan, "What Is 9/11 Truth?"
Many hands make light work!
RRREMA=research, realize, react, educate, motivate, activate
"It's been said, and I think it's accurate, that my husband was obsessed by terrorism in general and al-Qaida in particular." (Hillary

This isn't the factor of safety for the structure

What John Skilling was referring to was the fact that since the perimeter columns were also designed to handle rare high wind and seismic loads, as well as 40 to 50% of the gravity load of the building, that when dealing with gravity loads only the live loads could be increased by 2000%. Live loads are not the building itself but the people, furnishings, and equipment.

The actual factor of safety of the perimeter columns when considering gravity loads only was 5.00:1 and the actual factor of safety for the central core columns was 1.67 to 2.00:1. The central core was not intended to take lateral loads like wind or seismic loads. The reason the perimeter was relatively high when dealing with gravity loads only was due to its having to take these other rare loads.

There was no high wind or earthquakes on Sept. 11, 2001 so these safety factors were fully realized that day.

Great Post. But please give...

...Sources like Chucksheen did. It's good for the benefit of all.

EDIT: I'll do it myself. That's John Skilling quoted in the Engineering News Record refering to live loads only. (Find the below article to verify.)

"How Columns Will Be Designed for 110-Story Buildings, ENR, 4/2/1964"

What sources are really needed are your sources for the ratios you gave.

I did my own analysis on the factors of safety


I did my own analysis to estimate the factors of safety based on the scant information we have on the sizes of the columns and the mass of the building. You can read what I estimated in the endnotes of the paper "The Sustainability of the Controlled Demolition Hypothesis for the Destruction of the Twin Towers" at the Journal of 911 Studies.

Since I did that paper there has been some additional information available on the actual core column sizes throughout the building but not the wall thicknesses of the perimeter columns at every level. There has also been some headway made in determining the actual mass of the buildings, which seems to be less than the actual purported 500,000 tons, but that information is not yet published.

I believe my estimates for the factors of safety are somewhat close to the mark and they fit within accepted norms.

question about the structures

hi tony. you sound pretty knowledgeable about the technical aspects of the wtc structures. so i was wondering whether you could answer a basic question for me: if the outer columns and floors were instantaneously removed from the twin towers, would the core structures remain standing on their own? most of what i've read and watched on the subject of the collapses gives the impression that the answer is yes. and if the answer is yes, this of course makes the official story a complete joke. because it seems to me to land the purveyors of the official story in a dilemma: either the mechanism by which the floor structures were secured to the core were strong enough to tear the core structure down with them when the floors collapsed, or they were not. if they were strong enough to tear the core down, the whole idea of a "pancaking" of floor upon floor is dead in the water, since in order to pancake the floors would have to come away from the core structure. it seems to me that any form of piledriver theory of complete collapse is almost impossible to imagine once it's been stipulated that the floors must remain firmly fixed to the core structure. on the other hand, if they weren't strong enough to tear the core down, then the idea of some sort of pancaking is feasible, but the problem is that there's absolutely no explanation for the failure of the core.

there are however some things i've read which seem to indicate that the core and the outer columns were mutually supporting structures, to the extent that neither could maintain its integrity without the support of the other. prima facie, given a common sense understanding of the structure of the building core, this doesn't make much sense. its natural to understand the core as a self-standing anchor around which the rest of the building is constructed. but i can just get a grasp on the possibility that neither of the two major structural components of the buildings were designed to be free-standing. that, specifically, the core couldn't have been constructed first and independently of the rest of the structure, because it wasn't designed to be able to stand on its own; that it could fulfil its function as a core structure only once connected up, via the floor assemblies, with the outer structure.

if the latter were the case, it would be possible for the purveyors of the official story to explain why, once the floor structures pancaked away from the core, the core itself couldn't survive. of course, they'd still have a lot of trouble explaining how it somehow demolished itself into truck-length pieces! but at least they wouldn't have to resort to one of the only other two possible explanations: first, that the connections between floor assemblies and core were so strong that the collapsing floors dragged the core down with them (utterly ludicrous, and completely at odds with any common sense notion of a pancake collapse); or second, and even more ludicrous, the idea that the part of the core above the plane damage pile-drived the part below the damage, crushing eighty stories of densely interconnected steel beams to the ground, completely independently of the destruction of the rest of the building.

so was i just misinterpreting, or has this idea been presented or at least suggested in places. and if so, is it true?

thanks to you, or anyone else who can help me out on this...

The self supporting central core


I have heard some on the Internet, who defend the present government explanation for the collapses, try to say that the central core and perimeter columns needed the floor trusses to support them in a composite structure. I don't believe for a minute that the 137 foot x 87 foot central core was not self supporting when it's 47 columns were interconnected every 12 feet. It's 12 foot column lengths between supports were also too short for local buckling. Although rectangular in outward appearance the wall thicknesses of the columns thinned with height and it should have been self supporting. The central core was essentially a virtual structural pyramid similar to the Eiffel tower.

Any pancaking of the floors would have more likely sheared off the channel welded to the outer core columns, which was a platform for the floor trusses, before dragging down those large columns.

I believe that the core should have remained standing in any perimeter column or floor collapse scenario. The reason it probably did not is that it was the 24 outer columns of the central core which would have been taken out to precipitate the collapses. Taking out these columns would cause the perimeter wall to buckle through the floor trusses, it will take down the floors, and will also drag down some of the inner core columns until down lower where they were stronger and could withstand the beams pulling on them so that the beam to column connections broke first. This is why I believe some of the inner core columns remained standing after the collapse.


cheers for that. yeah, that makes things a lot clearer for me. all you'd have to do to bring the whole structure down is sever the outer columns of the core every few floors and then blow everything out.

but just why the magnitude of the explosions had to be such as to pulverize the concrete and building contents in mid air is not so clear...

Don't discount the impulsive loads

Joe, there is quite a lack of understanding out there concerning impulsive loads, which occur in high speed collisions. An impulsive load causes the force in a collision to be many times the weight of the colliding objects and thus magnifies the force. Of course this can only happen once something is free to fall in the case of a vertical collision.

I believe a vast majority of the pulverization was caused by the falling debris itself colliding with masses lower in the towers which may have already started moving but could not accelerate fast enough to get out of the way. A collision would have still taken place at a relative velocity. Many things would have been hit many times due to the higher velocity of the items already falling. Just think about thirty plus three story controlled demolitions occurring one on top of the other to imagine the destruction which would ensue.

I don't think the amount of explosive used had to be all that great relative to the task. I would be willing to bet that somewhere in the vicinity of 2,000 to 4,000 lbs. of explosive was used in each tower. If there was a demolition going on every third floor all the way down then that would be 30 plus controlled demolitions. So you would have had an average of about 100 lbs. of explosive per demolition floor and about 4 lbs. per outer core column. Of course, the upper floors would need less and the lower floors more due to the differences in wall thickness of the columns. I have looked at the energy output of RDX and the requirements to cut the columns at their welds and this looks to be in the ballpark.

Much of what we see in the collapses can be explained by gravitational potential energy being unleashed by the explosives cutting the columns. It is the speed of collapse which is the real tell tale sign of controlled demolition, as well as some of the plumes and squib ejections.

Don't forget that if this was done by a criminal network they wanted it to appear as natural and due to the plane impacts and fire so they would have used a minimum amount of explosive to do the job since the idea would be to keep it from being discovered. Taking out the core columns also kept most of the explosions from being visible. The stiff corners of the perimeter would also need to be weakened and this was probably done with the use of an incendiary such as thermate to eliminate any obvious explosions. They could then be pulled down by the outer core columns, floors, and trusses. The perimeter walls would have buckled and fallen outward due to the floor masses between them and the core.


haven't a number of calculations been done which show quite clearly that the gravitational potential energy available in the structures wasn't nearly enough to pulverize all that concrete, let alone cause the pyroclastic flows of fine dust which covered many blocks of lower manhattan? and, honestly, for me, it doesn't sit well with common physical sense when i look at the debris clouds mushrooming up and out. what's the top speed at which the concrete floors could have been impacting on one another? is it feasible that enormous blocks of concrete will turn to dust when they impact at such speeds? i'm not sure. i guess someone could drop a decent block from ten or twenty stories and let us know what happens. i wouldn't expect a cloud of fine dust to result. but i guess you can't always trust your intuitions on such questions.

but couldn't it be that the perpetrators anticipated that, because of the assymetry of the impact damage, it might well happen (as it in fact did in the case of the south tower) that the block of floors above the damage zone might begin to topple over, and that the only way to stop it from landing at some distance from the building was to blow it to pieces in mid-air. imagine that the top of the south tower had fallen off, but the rest of the building had nevertheless crashed to the ground at virtually free fall speed. i think a lot more people would have started to ask serious questions a lot sooner! (how would your model explain the tipping and subsequent disintegration of the top of tower 2?)

that doesn't provide a motivation, though, for making sure the rest of the structures were pulverized. so i'm a bit agnostic about this, i guess. perhaps it was a matter of destroying evidence; or just making the clean-up more convenient.

or maybe you're right. have you done any potential energy calculations which show the earlier calculations to be way off?

one thing's for sure - there's still a whole lot of intra-communal disagreement, even on the most fundamental questions. the important thing, i guess, is to keep asking questions until clarity and consensus emerge.

Look at the dust cloud from Bldg. 7

Bldg. 7 was a standard controlled demolition done from the bottom up and the dust cloud it created was enous when it hit bottom. Controlled demolitions create a lot of dust when they hit bottom. In the case of the towers their destruction seems to have been caused by a series of three floor controlled demolitions one on top of the other all the way down. At the bottom the debris was moving over 200 mph. Just try to imagine one three story controlled demolition at the top and its dust cloud emerging, now as it falls imagine another one right below it and realize that was happening every three stories all the way down with much of the mass below being hit by tremendous amounts of material many times, with each controlled demolition creating a cloud at the bottom of its initial fall and continuing to impact the lower floors. Many of the collisions happened at speeds over 100 mph.

As for the amount of concrete in the towers you have to understand what they were. There were 110 floors with 4.35 inch thick floors in the open area and the core areas having 5.00 inch thick floors. So you had an approximate volume of concrete 440 inches high over a one acre area. That is about 37 feet or three stories high over one acre.

I believe the dust cloud being proof of an energy deficit is overplayed. Controlled demolitions create enormous dust clouds at the bottom when they fall and that was occurring every three floors all the way down in the towers. The energy deficit is proved by the speed of fall. A collapse due to gravitational energy alone could not break all the steel joints and pulverize the concrete while maintaining the speed of fall witnessed. There would have been energy losses which would have slowed the collapse time.


thanks again, tony. you've given me a lot to think about. and helped me to see other possibilities.

i'd very much like to see a close technical analysis of all these questions. it seems to me that, in order to make sense of the speed of the collapse, the bottom floor of each three-floor demolition had to be taken out and on its way down well in advance of impact from the debris falling above it. so none of the demolitions apart from the very last "bottomed out" in anything like the way building seven did. i guess you're saying that the speed of each falling three-floor block relative to that of the block below was sufficient at the moment of impact to make sense of the enormous billowing clouds of dust that began to develop from the first instants of failure. but that doesn't ring true to me on an intuitive level, given the near free-fall speed of the collapse. that's why it'd be good to see some number crunching.

Skyscrapers are designed with robust factors of safety

and that is why there isn't a chance that the towers came down due to gravity alone. Without explosives only a huge dynamic load, like a meteor strike, could have done what we saw that day. Needless to say there wasn't one and there would not have even been a small dynamic load due to a fire induced collapse.

Your first sentence

mentions a 1/8th scale building. Can you add a brief qualifier of some kind, to give the reader some immediate context? What is the name/nature of this building/event to which you refer?

Otherwise, it sounds great.

Mental calisthenics.

It's almost amusing watching these otherwise intelligent people engaging in bizarre mental calisthenics just to avoid believing what their common sense and the laws of physics are telling them. Read this sentence. It is just f&*#ing bizarre.
"The topic is controversial in engineering circles. Clearly, for example, the toppling of the World Trade towers was "progressive," in that time passed before the damage inflicted by exploding passenger jets took its final toll."
They just need help breaking down the fragile wall of denial.

Prof. Jones - We really need to get you on NPR's Science Friday

with Ira Flatow.

Just last week while listening to the show I heard a neurologist, John Kessler, casually say " ...after all, we didn't know that jet airplanes could bring down skyscrapers until we saw it happen on 9/11."

Be great to get you on with some engineers to discuss this unprecedented, remarkable and under-discussed (in the media, anyway) event.

Regarding your letter, I would include an invitation to the Globe to send a reporter to your presentation combined with an offer for a sit down interview at their offices while you are in town (if you have time, of course).

Keep up the great work and come visit us in northern CA again, soon.


I hope that you and yours are all well.

Enjoy Boston!

You are a true American patriot and I'm always proud to stand with you.

The truth shall set us free. Love is the only way forward.

Some humble suggestions for a great man


I must say, your letter could be submitted as it is, and would serve its intended purpose admirably. However, having graciously asked for feedback, I'm sure you would not be opposed to hearing a few suggestions, however minute/inconsequential they might appear.

First, I have one quick question: Is it your hope or expectation that this letter be printed in the Boston Globe? Is it for the Editor's personal edification only? I certainly hope it will be published, though I could quite easily imagine a managerial cleansing session wiping out much of its "controversial" content (i.e. any statements based in our world of truth, concrete evidence, and reality). The above does not necessarily have any bearing on the potential final contents of the letter -- I'm just kinda' curious, is all.

Perhaps at the expense of economy and concision, I might lengthen the final paragraph of the letter, fleshing out to a greater extent the solidity, variety, and multiple-corroboration of the forensic, visual, and testimonial evidence pertaining to the controlled demolition hypothesis. The Editor should perhaps not be left with any impression to the contrary. Possible revision ideas follow in+boldface:

"On the other hand, we have all seen controlled demolitions using explosives in which tall buildings are brought straight down – completely and quickly. Of course, such a process,+in+addition+to+demonstrating+several+physical+phenomena+wholly+specific+to+the+procedure, leaves behind tell-tale residues. Such+residues,+which+are+generally+seen+as+proof-positive+of+arson+in+the+realm+of+criminal+investigation,+have+been+found+in+the+WTC+dust+--++not+only+by+our+team+of+investigators,+but+by+the+U.S.G.S.+as+well. I will discuss this+conclusive+forensic+evidence,+as+well+as+a+great+deal+of+corroborating+video,+pictorial,+and+testimonial+evidence, at Faneuil Hall on Dec. 15, 2007."

I dunno; maybe that would be a little 'over-the-top.' I do sometimes feel frustrated by the idea that so many people remain ignorant of the sheer quantity and quality of the 'Inside Job' evidence. Any little extra hints we can throw their way just might help them see how black-and-white this issue has become.

In any case, Dr. Jones -- God bless you, Godspeed, and thank you for teaching us so much. You are a true hero in an era at times horrifically rife with true villainy.

"All that is required for evil to fail is for good men and women to do something." -- Awake


I actually like the changes you suggested. I don't think they are over the top at all.

For what it's worth, I once asked a question pertaining to "progressive collapse" on Yahoo! Answers:;_ylt=AsqqFcJXWYnm3vtPKKeYN4rsy6I...

I think my question was pretty thorough and to the point. Nevertheless, despite my instruction to the contrary, people's responses still included WTC 1, 2, & 7 as examples of progressive collapse. Interestingly, one answer was pretty good and I emailed the individual who posted it, providing additional information about the controlled demolition hypothesis. I never received a response and, if I remember correctly, that person's answer is now missing, as if it were retracted somehow. . . . I like to think that my Yahoo! Answer question and follow-up letter actually changed that person's mind.

In any case, I really don't believe anyone will be able to create in a laboratory real-world models of progressive collapse that effectively mimic the collapses of WTC 1, 2, & 7. But it can't hurt to try.

Great letter, Dr. Jones. I can't wait to see the response.

excellent letter

Maybe, you want to formulate it a little more precisely - I am just saying because the debunkers are likely to latch on to any inexactly worded sentence.

For instance, you can say that while in the mock up they demolished a column completely, the main part of the core (if not the whole core) survived the mechanical damage in WTC 1, 2 and 7 and that the fires couldn't do much to it - then why did they disintegrate? Etc, etc.

Boris Epstein

7 floors per second

How do the engineers explain the fact that, in all three cases, on average about 0.14 seconds were available for the dropping AND total destruction of each floor?

How can any chain reaction happen in such a time frame?

Do these people even ask such questions?

Quote-But labeling the

Quote-But labeling the horror "progressive collapse" implies that engineering flaws were somehow to blame.

The first thing i would do in any investigation is to look for precedents and in this case we have two.Firstly the 93 bombing took out core columns and the building acted entirely as anticipated.Vierendeel action spread the load from the damaged columns to the undamaged columns exactly as John Skilling said would happen.Thus proving structural flaws were not evident.

Quote-As the column shattered at the base of the scale model structure in the basement lab, the downward force of the 5,000-pound load - metal weights simulating a real-life building's burden of walls, floors, and contents - shifted instantly, invisibly, to other beams and columns.

That is vierendeel action in action,i could have told you what would happen before they even broke the support.In the case of the towers John Skilling designed the whole building with this in mind.The mock building held in exactly the same way the towers held.The buildings held and would have continued to hold indefinately,there is no doubt about that absolute fact. The Vierendeel action would ensure that the elastic limits would never and could never be reached.

I love the quote from Donald Griersond (University of Waterloo)

“the toppling of the World Trade towers was "progressive," in that time passed before the damage inflicted by exploding passenger jets took its final toll. But labeling the horror "progressive collapse" implies that engineering flaws were somehow to blame.”
If not engineering flaws… then what? Sounds like he is suggesting we should examine possibilities other then poorly designed buildings as the reason for the spontaneous collapse of three massive steel structures.


Prof. Jones, We met the

Prof. Jones,

We met the Hartford symposium, so hello again.

I suggest contacting Mehrdad Sasani who ran the study before you send in your letter. You should have a discussion with this gentleman, perhaps in conjunction with Richard Gage. His contact info at It would be better to fully understand this experiment so that the best comparisons can be made to the WTC collapses.

It is also interesting that Sasani features several experiments on this site, which includes a 1/10 scale building that appears may have structural similarities to WTC 7. Please refer to

In your letter, it would be useful to mention and provide links to lectures on google/youtube that have been given by Mr. Gage, Kevin Ryan and youself on this topic. And lastly I would extend a formal invitation at the end of the letter your the Dec 15/16 meeting to the Editor/Staff, instead of just mentioning it.

Best Regards.

Thanks for all

the comments. I looked at them last night about midnight, made a few small changes to my letter to the editor, then mailed it off.
Of course, I hope it will be published, but I'm not holding my breath. I tried to keep it short, in view of standard restrictions on number of words.

Since then, a number of good points have been raised. Thanks for those.
"The Vierendeel action would ensure that the elastic limits would never and could never be reached." What is the Vierendeel action?

I went to M. Sasani's site, thanks Les -- very interesting. I wonder if he would be willing to set up a scale model of a Tower, now that we have the architectural drawings that should be feasible. That would be great! I'm very confident that a failure of a set of columns around the 94th floor (No. Tower) would NOT result in complete destruction of the building.

I wonder if he or someone with a similar lab would take on this experiment... Now that we've seen that such labs exist -- and the importance of the question -- who would take such a project on? I suspect a number of students would be willing to model one of the Towers and take some observations...

Experiment idea

I'd love to see a simple experiment with a steel framed building that has been marked for demolition. Here it is:

1. Use a steel-framed building; we'll assume 50 stories high
2. Rig three floors for demolition; let’s say floors 37, 38, & 39.
3. Detonate the charges and see what happens.

According to the government, once the "top chunk" starts moving, we should see the rest of the building completely disintegrate (all the way down to the ground) at near free-fall speed.

...And if it's that easy to pulverize a building from top to bottom, demolition companies can save themselves an awful lot of time, effort, and money in the future. …just rig a few upper floors and be done with it.


why didn't i think of that? a great idea! when i've thought of a crucial experiment that could potentially decide between the official and alternative explanations, i've always thought of the construction of scale models. the problem is, the more crucial you want the experiment to be, the closer the model would have to be to the original. and this would get very quickly out of hand financially. but it would be easier by orders of magnitude to set up a crucial experiment on a building that's already marked for demolition. damn, i'd be willing to contribute a couple of weeks wages to help make that happen!

You should write up a patent application

and see if the USPTO will accept it (they probably will as an actual working prototype is not needed to get a patent). That should be interesting. You could then go around shopping your invention at demolition companies all over the world. Think there'll be any takers? This could be the subject of a great documentary (a funny one, actually) if you think about it. You wouldn't even really need a patent application (which can be expensive). Just go the easy to write provisional patent route (which for $100 will give you limited protection for a year) and continue from there. Your invention would then be "patent pending".

Also, has anybody thought to write to the Guinness Book of World Records with questions related to WTC 1,2, & 7? What they would come up with if they investigated the collapses further? Would they risk their reputations on the NIST reports? I wonder.

Vierendeel trusses are

Vierendeel trusses are moment connected four jointed frames. They're technically not trusses which are pinned by default and have the characteristic triangle framing to keep the structure statically stable. Vierendeel action is just another way of expressing that a frame well redistribute loads because their moment connected.

The columns in the exterior of WTC 1 & 2 are moment connected parallel to the walls. The core columns are pinned. The mechanism that prevents core columns from just dropping when they are severed is not Vierendeel action. It is something entirely more complex.

The 1993 bombing however did not destroy any core columns. It did however damage the massive retaining walls that held soil in around massive concrete piers which delivered the weight of the building down to bedrock. Had these walls failed, the soil around the piers would have become uncompressed which would leave the concrete piers unconfined and in a state which they were not designed to be in. The foundation piers would likely have failed (brittlely and suddenly) causing the whole building to topple.

Thanks Newton .Your right

Thanks Newton .Your right that vierendeel action doesn,t explain the core as i meant to say catenary action.The catenary action combined with the vierendeel action of the perimeter columns made the buildings not only amazingly strong under load they also made them amazing at distributing load.The vierenndeel action would spread the load from the damaged perimeter columns completely around the building.The opposite side in tension,the damaged side in compression and the two adjacent sides in a combination of both.The fact is this,the damage caused no more compression,tension and torsion than a hurricane wind would.The damage was way inside the limits of the building.It is a fallacy that the columns adjacent to the damage got overloaded.

NIST say! Perimeter Moment Frame Arrests Failure Progression: Analysis of the global structure indicates that the structure redistributed loads around the severed and damaged areas. A progression of column failure to adjacent columns would have been arrested by the vierendeel action of the perimeter moment frame, which could span across a sizeable opening due to the strength and stiffness of the frame.

This is an admission that the perimeter damage had no bearing on the collapse.The huge interconnected mass of the core is even easier to debunk as the cause of collapse.The damage was nowhere near sufficient to do anything of any note and that was because John Skilling DID take this scenario into consideration..

So how do you weaken the building to collapse when it was specifically designed not to.As Tony has already pointed out the core was greatly weakened,all the evidence points to this.Which part of the building would overcome the load transfering forces?the corners.We all saw the corner being attacked,there is no doubt molten ferrous material was spewing from that corner.Once the corner had failed all load transfering forces were greatly diminished.Collapse initiation was complete and the weakened core could not arrest collapse.There was nothing left to resist it.This is my theory on what happened and i think if this is how they did it and make it look the way it did then all i can say is it was almost a work of art.John Skilling actually said if demolition experts wanted to bring the towers down he would bet that they could.Demolition is the only explanation.

Catenary action is almost

Catenary action is almost never part of the principle design of buildings, however. With good reason. The inelastic analysis is non-trivial and most of the research done in it was classified and restricted to DoD use. Only in the past 20 or so years has it become declassified, however even then it has trade restrictions to many countries. It wasn't available to civil engineers in the 60's. The method for accurately analyzing the structural effects in large buildings was in it's infancy in the 60's (I'm referring to finite element analysis) and even then restricted almost exclusively to a few professors at a few universities who were trying to understand that method and the airline industry (which developed it).

If you go through a quick analysis on the catenary action of the trusses, you can learn a few things. First the floor trusses become the principle mechanism in holding up a column load (which they were never designed to). Each interior column has only four trusses connected to it with some fairly flimsy seat connections that aren't designed to take much more load than just the shear reaction of the truss. These trusses cannot resist the entire load themselves. The only remaining element left to resist collapse is the hat truss which was also not designed to resist ten+ stories of a column in almost complete tension.

The damage to the perimeter columns in pretty much moot, they can easily redistribute the load. The real question is how many core columns were damaged beyond being able to bear load and how bad the fires were near those columns.


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