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September 11 and Fracture Mechanics

On the Collapse of the World Trade Center in New York
on September 11, 2001


The generally-accepted explanation of the collapse of the World Trade Center towers on September 11, 2001 is based on the speculative “theory” of progressive buckling of bearing columns at the speed of free fall triggered by creep buckling of the columns of the floor subject to the conflagration from the spilled fuel, and by dynamic impact of the upper structure. In the present paper it is shown that this official “theory” is wrong because it is built on false assumptions and incorrect calculations. The “theory” cannot explain the free fall, explosion sound, and pulverization of the buildings as well as other facts of this event. The simultaneous collapse of the neighboring 47-story tower directly contradicts to the “theory”. It is shown that, consistent with all known facts of the matter, the scenario of all collapses was this: (i) heating of bearing columns in the “hot” spot caused high compressive thermal stresses in these columns, (ii) these stresses combined with internal stresses triggered a fracture wave, and (iii) the fracture wave disintegrated the entire building by invisible cracks for less than 0.1 s producing the sound of explosion and providing the conditions necessary for free fall of steel fragments and dust clouds of tiny fragments of glass, marble and concrete. The theory of fracture waves, see Appendix 1, supports this scenario. The official “ theory” is placed in Appendix 2.


1. Introduction
2. Triggering mechanism: thermal stresses vs. creep
3. Dynamics: accurate vs. approximate analysis
4. Free fall: fracture wave vs. progressive failure
5. Fracture wave vs. shock wave
6. Conclusion
Appendix 1. The theory of fracture waves
Appendix 2. The official "theory"

1. Introduction

“Why did you think the towers collapse?”, Larry asked his guest, a prominent member of the September 11 Commission, on a recent Larry King show. “This is still under investigation”, the guest answered. Evidently, the public has not, as yet, accepted the “theory” by Bazant and Zhou (2002), see Appendix 2. Meanwhile, the engineering community has, without any hesitation, recognized the “theory” as correct and comprehensive. This author has felt this official recognition on his own skin after the editors and anonymous referees of numerous technical journals refused to publish his understanding of the collapses as contradicting to this “theory”. The most important conclusion Bazant and Zhou derived from their analysis was that the WTC collapse was an unavoidable consequence of the terror act. This conclusion was necessary to both sides. To the American government, for to make the turn to the new policy designed before. To terrorists, as a recognition of success of their strategy and an encouragement to start jihad around the world. Meanwhile, on the opinion of the same engineering community, this terror act could not cause a WTC collapse. Otherwise, all people would have been evacuated from the buildings during the fire, and 300 firemen would not have been ordered to climb up, so that, instead of three thousand, the fatalities would not have exceeded about one hundred people. The collapses happened unexpectedly. My point proved below is that Bazant&Zhou’s analysis and conclusion are wrong and that the collapse was a result of insufficient knowledge of fracture, and especially fracture wave, mechanics ignored both in the construction of towers and in the prediction of what could happen after the terror act.
The “theory” has suggested the following scenario of the collapse: creep buckling of bearing columns of the critical floor, free fall and dynamic impact of the upper structure, and progressive, floor-by-floor, buckling failure of bearing columns of the underlying structure. This “theory” has been unable to explain these well-known facts of the matter:
(i) Free fall regime of all collapses;
(ii) Sound of explosion produced by each collapse;
(Sound is generated by cracking. If the cracking had continued for ten seconds, as the “theory” asserts, a boom would have been heard, not an explosion.)
(iii) Pulverization of the buildings collapsed .
(By the “theory” the debris after the collapse would have consisted of steel segments of columns about two meters long, and nothing more.)
According to the “theory” the neighboring 47-story building should NOT have collapsed. But, it did.
According to the “theory” the Empire State Building should have collapsed in 1945 under similar conditions of aircraft crash and conflagration. But, it did NOT.
Meanwhile, for every person familiar with industrial implosions, when a building is intentionally demolished by uniformly distributed explosives to produce small debris for their easier transport, the WTC collapse has strikingly resembled that of a designed implosion caused by previously distributed explosives. Indeed, each tower collapse took about ten seconds, that is all parts of each building were falling free, without any resistance. It is exactly what happens after a building is disintegrated by explosives. It is no wonder that the conspiracy theory, consistent with the well-known facts of the matter contrary to the official “theory”, has become widely spread in the world. In the speech on the popular TV channel C-SPAN on April 18 and May 7,2005 David Ray Griffin who is a famous public figure in the U.S. gave an explicit overview of the events of September 11, 2001. He indicated the following facts: (i) Close ties of the families of Bush and bin Laden in common oil business in Saudi Arabia; (ii) bin Laden was a CIA agent in the 1980s when he fought against Russians in Afghanistan; (iii) No one from the bin Laden family (brothers, sisters, wives, adult children) has ever been detained or prosecuted; (iv) Many members of the bin Laden family living in the U.S. before September 11,2001 and celebrating these events were, without any investigation, allowed to leave the U.S. using an airplane that flew over the U.S. territory on September 12, 2001 when all other flights were strictly prohibited; (v) Several of 19 terrorists who committed the suicide mission on September 11, 2001 were arrested the day before because of invalid documents but, then, miraculously released; (vi) FBI and CIA knew about a terror act before that day; (vii) In December 2001 when bin Laden was in Tora Bora—which was well-known to the U.S. intelligence—the U.S.military refused from assaulting the bin Laden troops and allowed him to escape; (viii) Investigation of the collapse of the WTC towers was assigned to the National Institute of Standards (NIST), that is a government institution, and not to much more prestigious bodies like MIT or Harvard which are private and more independent institutions (indeed, to the best of my knowledge, in NIST there are no experts in fracture mechanics, at all) ; (ix) The U.S. raised Al Caeda and many its branches including the Chechen body. The terrorist organizations have been affiliated with CIA and other U.S. intelligence agencies that selected, financed, instructed, and directed the terrorists. Many facts of this affiliation can also be found in the book “The War on Truth” by Nafeez Ahmed. The discussion of this book took place on the American TV channel C-SPAN2 on July 23 and 31, 2005. Recently, I myself had an encounter with some Chechens from Russia who admired bin Laden, lived for free on government subsidies, took the instruction here, and were, better than a common American, protected by the American government. And so on. David Ray Griffin rejects the official theory of the WTC collapse as a hastily concocted one contradicting to the well-known facts of the matter. Indeed, the paper of Bazant and Zhou where the official theory was first published was submitted on September 13, 2001. I, personally, can’t imagine that such an important study could be done for one day. Dr. Bazant who is a renowned scientist well-known by his work in creep and fracture of concrete was, probably, used to mislead and misdirect the engineering community. Despite the evident blunders and miscalculations indicated in Sections that follow his theory has never been criticized in scientific press. Moreover, Dr. Sunder from NIST using a numerous research team and unlimited resources invented a numerical model supporting all basic points of the theory. All facts of the collapse indicated above as well as the fire itself were, again, ignored in this model that describes the collapses seen on the pictures obtained from cameras outside the building. Surely, the cameras could not notice the cracking of the building just before the collapse. On the opinion of David Ray Griffin, U.S. government agents acting together with bin Laden used the terrorists for their mission , mined beforehand two towers and the neighboring 47- story skyscraper by explosives which were detonated in a while after the crashes. David Ray Griffin thinks the September 11 events like the arson of Reichstag in Germany in 1933 were necessary for those government circles who designed the plan of the American rule of the globe in the document entitled “American Century” issued still in 1993. Wolfowitz who is the first deputy of the Secretary of Defense has been the mastermind of this plan. He is viewed as the main brain power behind the wars in Afghanistan and Iraq. Indeed, September 11,2001 became a landmark separating the American history before and after. A myth that some peoples hate Americans and wish to kill them was created. All international laws and treaties were broken, and the era of preemptive wars, interventions and occupations has begun. The American military, police, and intelligence have gotten the right to search and detain anyone on the Earth without an indictment and to use any means including free access to finances, mail, telephone talks, private life, etc up to the assassination. I, myself, was twice stopped—probably, because of my beard—and my car was searched for explosives and weaponry. Miami metropolitan area is under regular surveillance by police, guards, and dogs seeking for smell of explosives. The recent attempt of assassination of Chavez who is the President of Venezuela is another example. The wars in Afghanistan and Iraq, the first step for the control of the Arabian and Caspian oil according to the “American Century”, started just after September 11 and are still on. However, the military expenses for a much bigger war are many times greater than for anti-terror activities and greater than the military expenses of the rest of the world. Enormous funds have been released for strategic arms including super-penetrating bombs, interception stations, a new generation of submarines and nuclear bombs, the armament of military satellites, and on, and on. The new arms race has begun at an unprecedented rate. Starting the Iraq war, President Bush warned that the use of the “nuclear weapon is not taken from the table”. No doubt, it would be used to eliminate Baghdad if the American troops were defeated; and so, the guerilla war was the only choice for Iraqi patriots. Who, specifically, would be interested in a war or, moreover, a big war? The answer is evident, “Nobody” and “There are no enemies, at all”. However, there are about four hundred billionaires and about four million millionaires in the United States. They carry out the main mission of the U.S. which is “Money is the power”. Their power is tremendous , although hidden due to competition like the energy of nucleons in a nucleus. It is multiplied many times by the sixty-million army of smaller investors supported by media, military, and 14 intelligence agencies. One American billionaire can make his government in, and control, such country as Estonia, or Armenia, or Georgia. He does not do this action only because he does not see how to increase his wealth by this way-- it is not a good investment for him , so far. The American passion for making money embodied in corporations creates the enormous resultant force no state, country, or government can withstand. Nobody can surpass them in money-making business based on legitimized deception and enforcement. Like a good sailor who can drive a sail boat against a wind this force can drive this great country against the wind of morality, public opinion, fear of nuclear war etc in any direction where is the smell of money. After the fall of Soviet Union, when the anti-money world system collapsed, dollar via convertible currencies became the master of the whole world. The U.S. is run not by the President or Congress, but by the Federal Reserve which is a private organization of billionaires.
In what follows, it is shown that the official “theory” of the WTC collapse is built on false assumptions and miscalculations, and hence IS wrong; and a scientific explanation consistent with all known facts is suggested.

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