![]() Given the nature of the collapse, any investigation adhering to the scientific method should have seriously considered the controlled demolition hypothesis, if not started with it. Finally, the collapse was rapid, occurring in less than seven seconds. Its steel frame was almost entirely dismembered and deposited mostly inside the building’s footprint, while most of its concrete was pulverized into tiny particles. Its transition from stasis to free fall was sudden, occurring in approximately one-half second. They write:” The total collapse of WTC 7 at 5:20 pm on 9/11, is remarkable because it exemplified all the signature features of an implosion: The building dropped in absolute free fall for the first 2.25 seconds of its descent over a distance of 32 meters or eight stories. The physicists also note the Towers were specifically designed to withstand the impact and destructive force of airliners crashes. In addition to resisting ever-present gravity loads and occasional fires, high-rises must be designed to resist loads generated during other extreme events – in particular, high winds and earthquakes. Countless other steel-framed high-rises have experienced large, long-lasting fires without suffering either partial or total collapse. Throughout history, three steel-framed high-rises are known to have suffered partial collapses due to fires none of those led to a total collapse. Thus, if a localized failure occurs, it does not result in a disproportionate collapse of the entire structure. Steel-framed high-rises are designed to be highly redundant structural systems.Structural members are protected by fireproofing materials, which are designed to prevent them from reaching failure temperatures within specified time periods.Most high-rises have fire suppression systems (water sprinklers), which further prevent a fire from releasing sufficient energy to heat the steel to a critical failure state.Here, 67 percent of the strength would need to be lost for failure to ensue, which would require the steel to be heated to about 660☌) In the case of WTC 7, for example, the factor of safety was generally 3 or higher. Fires typically are not hot enough and do not last long enough in any single area to generate enough energy to heat the large structural members to the point where they fail (the temperature at which structural steel loses enough strength to fail is dependent on the factor of safety used in the design.Here are some of the observations the researchers offered: They noted that “15 years after the event a growing number of architects, engineers, and scientists are unconvinced by that explanation.” The researchers also found “the only phenomenon capable of collapsing such buildings completely has been by way of a procedure known as controlled demolition, whereby explosives or other devices are used to bring down a structure intentionally.” ![]() The report also concluded: “Given the far-reaching implications, it is morally imperative that this hypothesis be the subject of a truly scientific and impartial investigation by responsible authorities.” “Did we witness an unprecedented event three separate times on September 11, 2001?” “It bears repeating that fires have never caused the total collapse of a steel-framed high-rise before or since 9/11,” the researchers write. But even the NIST found that the three buildings were “the only known cases of total structural collapse in high-rise buildings where fires played a significant role.” It found both the Twin Towers, as well as the 47-story World Trade Center Building 7, which was not struck by an airplane, all collapsed as a result of fires and intense heat. National Institute of Standards and Technology launched what would become a six-year investigation of the three building failures that occurred on 9/11. Obviously, the content of this article is the responsibility of the authors.” However, given the timing and the importance of the issue, we consider that this feature is sufficiently technical and interesting to merit publication for our readers. The study is the work of Steven Jones, former full professor of physics at Brigham Young University, Robert Korol, a professor emeritus of civil engineering at McMaster University in Ontario, Canada, Anthony Szamboti, a mechanical design engineer with over 25 years of structural design experience in the aerospace and communications industries, and Ted Walter, the director of strategy and development for Architects & Engineers for 9/11 Truth, a nonprofit organization that today represents more than 2,500 architects and engineers.Ĭonscious of the controversial nature of the report Europhysics included an editor’s note with the study in the September 2016 issue: “This feature is somewhat different from our usual purely scientific articles, in that it contains some speculation. ![]()
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