Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Collapse of building #7 on 9/11

  1. Sep 11, 2018 #1
    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?
     
  2. jcsd
  3. Sep 11, 2018 #2

    Bystander

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Yes.:sleep:
     
  4. Sep 11, 2018 #3

    russ_watters

    User Avatar

    Staff: Mentor

    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.
     
  5. Sep 11, 2018 #4
    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. Sep 12, 2018 #5

    DrClaude

    User Avatar

    Staff: Mentor

  7. Sep 13, 2018 #6

    DrClaude

    User Avatar

    Staff: Mentor

    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.

    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.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted