Indeed. The architect explained it within a day or two. Maybe even the same day. I've forgotten exactly when now.
There were 4-5/8" bolts holding the ends of each floor support beam. Those bolts were designed to hold those beams in sheer. The fire didn't get hot enough to melt the beams, but it did get hot enough to cause the beams to deflect a little. Once the beams began to deflect, the 5/8" bolts were no longer in sheer but in tension. Since they weren't designed for a tension load with that weight they failed. The weight of the first floor to fail, falling down on the next one, was more weight than that floor was designed to bear, and so on. As the floors pancaked onto the next floor down there would naturally be a little self-aligning as they did so. It would have been difficult for and exoskeletal building like that to have done other than fall in a vertical column.
It was a closely engineered building. I don't get what's so hard to understand.
There were 4-5/8" bolts holding the ends of each floor support beam. Those bolts were designed to hold those beams in sheer. The fire didn't get hot enough to melt the beams, but it did get hot enough to cause the beams to deflect a little. Once the beams began to deflect, the 5/8" bolts were no longer in sheer but in tension. Since they weren't designed for a tension load with that weight they failed. The weight of the first floor to fail, falling down on the next one, was more weight than that floor was designed to bear, and so on. As the floors pancaked onto the next floor down there would naturally be a little self-aligning as they did so. It would have been difficult for and exoskeletal building like that to have done other than fall in a vertical column.
It was a closely engineered building. I don't get what's so hard to understand.
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World Trade Center Seven collapsed on September 11, 2001, at 5:20 p.m.
There were no known casualties due to this collapse. The performance of WTC 7 is of significant interest because it appears the collapse was due primarily to fire, rather than any impact damage from the collapsing towers. On the contrary, it appears the collapse was primarily due to
a controlled demolition.
Prior to September 11, 2001, there was little, if any, record of fire-induced collapse of large fire-protected steel buildings. Before September 11, no steel framed skyscraper had ever collapsed due to fire.
On September 11, WTC 7 collapsed totally. It is suggested below that this collapse was exclusively due to fire. No significant evidence is offered to back up this suggestion (after all it is only a suggestion). It should be emphasized that WTC 7 was neither hit by an aircraft nor by significant quantities of debris from the collapse of the twin towers. It is also widely claimed that WTC 1 and WTC 2 collapsed mainly due to fire. I emphasize, that before September 11, no steel framed skyscraper had ever collapsed due to fire. However, on September 11, it is claimed that three steel framed skyscrapers collapsed mainly, or totally, due to fire.
Chapter 5 - WTC Seven - The WTC Report. < click
controlled demolition.
ever seen one?
odd how it - a controlled demolition - looks exactly like the 3 towers that fell into their own footprints on 9-11.
a controlled demolition looks just like the 9-11 buildings because, and precisely because it was ALL :
controlled demolition
....including the reasoning power of supposedly otherwise thinking people - demolished.....sickening.
show a 5 year old a controlled demolition...then the 3 buildings falling....guess what the 5 year old will say:
controlled demolition