Collapse of building #7 on 9/11

In summary, the official NIST report on the collapse of building 7 on 9/11 states that the thermal expansion of a floor beam caused by the fires was the main cause of the collapse. However, the report also lists three additional contributing factors and suggests more than a dozen recommendations for mitigating them. The report does not mention a common basement shared by building 7 and the twin towers, and concludes that the fire was enough to explain the collapse without significant impact from structural damage.
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alantheastronomer
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The official NIST report on the collapse of building 7 on 9/11 states that the thermal expansion of a floor beam due to the fires disrupted a support column on the thirteenth floor, and that is what ultimately caused the building to collapse. Is this the sole cause or could there have been other contributing factors?
 
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  • #2
alantheastronomer said:
sole cause or could there have been other contributing factors?
Yes.:sleep:
 
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  • #3
alantheastronomer said:
The official NIST report on the collapse of building 7 on 9/11 states that the thermal expansion of a floor beam due to the fires disrupted a support column on the thirteenth floor, and that is what ultimately caused the building to collapse. Is this the sole cause or could there have been other contributing factors?
Have you read the report? There are three additional explicitly listed contributing factors and more than a dozen recommendations for mitigating them and other potential contributing and tangential factors. Your one sentence summary is a good start, but the reality is far more complicated.
 
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No, I just read the Wikipedia version. What are the contributing factors that you know of? Do you have a link to the report? The reason I'm asking is that when I was listening to the radio when it was happening, they mentioned that building 7, unlike the others in the area, shared a common basement with the twin towers, although I haven't heard mention of this since. This got me to wondering about, when the North Tower collapsed, might it have pressed air into building 7's basement, weakening it's foundation?
 
  • #6
alantheastronomer said:
they mentioned that building 7, unlike the others in the area, shared a common basement with the twin towers
Looking (quickly) at the report, I see no mention of this common basement when they discuss the connection between building 7 and the rest of the WTC.

alantheastronomer said:
This got me to wondering about, when the North Tower collapsed, might it have pressed air into building 7's basement, weakening it's foundation?
It appears that the report found that the fire was sufficient to explain what happened to building 7. They say that even the structural damage from the debris of the North Tower played no significant role.
 
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Related to Collapse of building #7 on 9/11

What caused the collapse of building #7 on 9/11?

The official report states that the collapse was caused by the combined effects of fire and structural damage from debris from the collapse of the nearby North Tower.

Were there any other factors that contributed to the collapse?

Some people argue that controlled demolition was involved, but the official report and multiple investigations have found no evidence to support this claim.

Has the collapse of building #7 been thoroughly investigated?

Yes, the National Institute of Standards and Technology (NIST) conducted a thorough investigation into the collapse and released a comprehensive report in 2008.

Could a fire alone cause a building to collapse?

It is possible for a fire to cause a building to collapse, especially when combined with other factors such as structural damage. In the case of building #7, the fire burned for several hours and weakened the building's structural supports, leading to its collapse.

What lessons have been learned from the collapse of building #7 on 9/11?

The collapse of building #7 has led to improvements in building codes and fire safety measures, as well as increased awareness of the potential risks of fire in high-rise buildings. It has also highlighted the importance of thorough investigations and reporting in the aftermath of major disasters.

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