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V 1.41
Copyright 2003-2013,
911Research.WTC7.net site last updated:3/21/13
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Background Attack Aftermath Evidence Misinformation Analysis Memorial

Other Building Collapses

Only Demolition and Earthquakes Have Leveled High-Rises

That people would readily embrace the official story that plane impacts and/or fires caused the total collapse of three skyscrapers on September 11th could be predicted from the currency of the concept of building collapse, supported by the periodic reports of thousands dying from collapsing buildings in severe earthquakes. Lost are distinctions between building types, between building standards, and between degrees of collapse.

  • Nearly all the buildings that claim earthquake victims are heavy masonry low-rise structures, not steel-framed high-rise structures.
  • Collapses of buildings of any type of construction are rare in the developed world, whose building standards anticipate severe stresses.
  • Nearly all building collapses not involving controlled demolition are partial rather than total.

Excepting the 9/11/01 anomaly, the only documented cases of high-rise buildings undergoing complete collapse involved either controlled demolition or severe earthquakes. Of those, only controlled demolitions have caused such buildings to fall vertically into their footprints, leaving relatively small rubble piles, as was the case with WTC 1 and 2, and Building 7. In fact there are numerous observed characteristics of the destruction of the Twin Towers that have not been observed in natural collapse events.

LINK

Earthquake Induced Collapses

The total collapse of steel-framed buildings appears to be an extremely rare event, even when large earthquakes are involved. In the Kobe and Mexico City earthquakes, many such buildings were severely damaged, and some experienced partial collapse. A 21-story office building in Mexico City appears to be the only such structure that has suffered a collapse described as total as a result of a stress other than controlled demolition.

LINK

The 1985 Mexico City Earthquake

On September 19, 1985, Mexico City was rocked by a massive earthquake measuring 8.1 on the Richter scale, which severely damaged numerous buildings. At least one steel-framed office building experienced total collapse, according to the NOAA website. 1   However, the photograph shows that the remnants of this 21-story building included several apparently intact stories. This contrasts with the pulverized remains of the 110- and 47-story skyscrapers of the World Trade Center.

The 1995 Kobe, Japan Earthquake

building collapsed in 1999 Taiwan earthquake
Buildings partially collapsed by the 1999 earthquake in Taiwan

In January 18, 1995 an earthquake with a local magnitude of 7.2 struck close to Kobe, Japan. The quake was particularly damaging to the city because its focus was shallow -- less than 20 km below the surface -- and lasted about 20 seconds. Although the quake destroyed tens of thousands of buildings, many of the structures built since 1981 conformed to strict seismic codes. Most of these -- especially modern ductile-frame highrises -- were generally undamaged. 2  

The 1999 Taiwan Earthquake

On September 21, 1999 an earthquake measuring 7.6 on the Richter scale shook the city of Taichung, Taiwan, killing 2,375 people. The epicenter was near Nanto, and 145 km south-southeast of Taipei. 3   The quake toppled 13,000 high-rise apartments. 4   It appears that the only buildings that suffered total collapse from this earthquake were low-rise masonry structures.

LINK

Other Building Collapses

Defenders of the official explanation that the jetliner crashes and fires induced the total destruction of the Twin Towers and Building 7 have been unable to cite even a single example of the total collapse of a skyscraper from any cause other than controlled demolition. Consequently they have cited collapse incidents that do not even remotely resemble the cases of the World Trade Center skyscrapers.

MIT Professor Thomas Eagar has cited the example of the McCormick Place Collapse as an example of the collapse of a steel-framed building induced by fire. However, the McCormick collapse involved only the building's roof, and the structure was not comparable to any part of WTC 1, 2, or 7.

A reviewer of a draft paper by Jones ( Why Indeed Did the WTC Buildings Collapse?) cited the Sampoong department store collapse to counter Jones' claim that the symmetry of the WTC collapses indicated demolition. However, available reports and photographs do not support the reviewer's claim that the collapse was symmetric, nor would the symmetry of the collapse of the five-story structure be relevant to the symmetry of the collapse of a skyscraper such as Building 7.

Other critics of Jones have cited the L'Ambiance Plaza building collapse, calling it a total progressive collapse. However, the L'Ambiance Plaza was under construction and apparently employed deficient temporary structures. Deficiencies in the incident's investigation prevent the accurate characterization of it as a progressive collapse.


References

1. Earthquake Damage in Mexico City, Mexico, September 19, 1985, [cached]
2. KOBE 1995, vibrationdata.com, [cached]
3. Taiwan, Province Of China : Earthquake : 1999/09/21, adrc.or.jp, [cached]
4. Taiwan earthquake, BBC,

page last modified: 2011-09-08