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September 11 and Fracture Mechanics

          Once a man got a nasty sneeze and an earthquake started, occasionally at
          the same time, which destroyed a city the man threatened before. This man
          was declared to be the cause of the destruction and executed. This tragicomedical
          tale reminds me the real, recent history.

September 11, 2001 noted by the spectacular fracturing event, the destruction of the Trade Center, has become a landmark separating the history before and after. This fracturing event has already caused two major wars, millions of lost or destroyed lives, economic depression, several hundreds of billions dollars for taxpayers, and the fear spread around the globe. Amplified by the politicians it turned into somewhat like the biblical event of the destruction of the Tower of Babylon. Willingly or unwillingly, the politicians have glorified the terrorists, the perpetrators of this event, and their ideological leader Osama Bin Laden. The figure of Osama has grown to the mythical dimension of the embodiment of Evil proclaimed by President Bush. Now, Osama is for terrorists like Karl Marx was for communists a century ago.
But, what analysis of this fracturing event has been done by the scientists, experts in fracture mechanics? By those famous ones from MIT, Harvard, Stanford and other grand universities? None, or almost none*. They gave green light to politicians. Meanwhile, like the failures of Liberty ships during the World War II made a road for the Griffith-Irwin fracture mechanics, the destruction of the Trade Center should open a way for a new era in fracture mechanics, given the proper cause-consequence analysis of this fracturing event. How come that the plane could destroy to dust this majestic building made of steel and superstrong glass, the mass of which was almost a million times greater that the mass of the planes? It is like to turn a military tank into dust by a bullet. Isn’t it impossible? “Yes, it is impossible”, thought Osama who probably took the course of old Griffith-Irwin fracture mechanics while studying civil engineering. That’s why he, on his own (
* No single expert in fracture mechanics took part in the September 11 Commission as well as, by the way, in the Commission of the Shuttle disaster) confession, and his “brothers” terrorists did not even dream of the destruction of the whole World Trade Center. Their suicide mission was sooner an act of desperation intended to produce maximum noise to attract the attention of the world to their cause of Muslim freedom. But, they did not hope for such a destruction and glory.
It is only after September 11 that the terror has, owing to politicians, become a real movement, tested by practice, and a real danger. (Now, Osama probably regrets that his “brothers” did not study a smarter way to harm using nuclear and biological means of destruction instead of such a primitive ones. No doubt, they study them now.) Meanwhile, the right, timely, scientific analysis of this fracturing event would have proven that the “success” of the terror mission was due
not to the smartness of the terrorists who outwitted the CIA.
The real cause of large scale destruction
is the construction of overstressed buildings and structures, in general. The builders and designers of such unsafe structures bear most blame for the large scale of real or possible destructions. New building standards are necessary based on the new era fracture mechanics. A scientifically correct design would make the destruction and damage a dozen times less; in other words, it would solve ninety percent of the terror problem similar to the September 11 destruction. The scientific approach requires much less investments than three hundred billion dollars already spent to darn the security problem that was responsible only for ten percent of the destruction.
The fracturing of overstressed structures occurs by fracture waves propagating at the speed of sound in the material and
is resulted in a self-explosion of the material into a dust cloud spreading over to the environment [1]. This kind fracturing may be initiated by a comparatively small cause that, by itself, can produce a destruction of only a small volume, which, however, can also create a fracture wave that can turn the whole structure into dust, for whatever large size of the structure. Clearly, this type of fracturing is of special danger for large scale buildings and structures. It should be taken into account by designers and engineers of such buildings, which has never been the case.
This type of the fracturing of overstressed structures was called
the self-sustaining fracture [1]. It has been well known to the miners since long ago by explosive rock bursts [1]. The theoretical and experimental study of self-sustaining fracture began in 1967 when it was experimentally reproduced in a laboratory on glass specimens [1].
The destruction of the Trade Center on September 11, 2001
is nothing but the self-sustaining fracture of this building initiated by the impact of the planes. If we will not pay attention to the scientific study of this phenomenon to control or limit it, in the future we may face a situation when a single sneeze can cause such, or even greater, destruction.

[1] G.P. Cherepanov, Mechanics of Brittle Fracture, McGraw-Hill, New York (1979) 950 pp.

More On the Collapse of the World Trade Center


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.


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