[summer]

From above NYT article:

"Other experts agreed that the extreme conditions caused by the fire, and not unusual vulnerabilities of the buildings, were the likely causes of the collapse."

[daviddennis]

Interesting article; thanks for posting it.

I don't think there should be any liability extended to the architects and engineers responsible for the construction of this building. Current jets are much larger than those in existance when the WTC was designed, so both the crash load and fuel are much greater hazards.

That being said, is there any way a hypothetical WTC replacement could be protected from such dangers?

D

[Jean S]

Here's the link:

Believed to Be Safe, the Towers Proved Vulnerable to the Intense Heat of a Jet Fuel Fire

[gwrulz04]

After everything is figured out, the question also has to be asked why emergency personnel were put in harms' way when any engineer would know that the two buildings were now really vulnerable to collapse. Sure, we must try to evacuate and save as many people as possible, but why not take that precaution?

[Jim Boyd]

I am a professor of Aerospace Engineering at Texas A&M University. http://aeromaster.tamu.edu/Faculty/boyd.html I did my Ph.D. work in structural analysis of high temperature materials, with a focus on materials for jet engines. I teach materials science and structural analysis. For the record, I believe that the OK City building was brought down by contact explosives within the building, and I believe that a missile destroyed TWA 800. However, today's tragedy is easily explained in terms of the heat weakening the steel structure. The mainstream interpretation is correct. I doubt that the fire would be hot enough to melt steel, but even at 1300F the strength of steel is seriously degraded. These structural steels used in civil engineering are not intended for high temperature. The fire weakened the steel, and the upper floors crashed into the lower floors and the structure pancaked. Jim Boyd

[Looking for Diogenes]

Here's another thread on explanations of the WTC collapse.

Why the towers collapsed: hit at vulnerable point

[PhiKapMom]

Thanks for posting this article! Sure makes a lot of sense!

[BunnySlippers]

Bookmark.

[Slewfoot]

While most of what is said in this post is correct, it and practically everyone else calls this a jet fuel fire. It was not. Sure the jet fuel really helped start the fire, but it was gone in the first couple of minutes. The fuel tanks were shredded on impact and the liquid fuel dispersed.

When you see the tapes of the crash note the huge red flames that was the jet fuel, a couple of minutes and they are gone with the fuel. Then you see thick black smoke. This was furniture, carpet, files full of paper, but mostly the remains of an airliner. Airliners burn very well even without jet fuel. They burn very hot too. Hot enough to melt the steel in the WTC.

[rockfish59]

hate to jump into this snake pit but next time you go by a construction sight, look at the material they spray on the steel. it's called 'monocoat'. it's a fire retardant. it protects the steel from fire. knock it away and add tremendous heat and you have structural failure. steel is very malleable when hot. it draws and holds heat for a long time. put a blow torch to an i beam for 10 seconds and then try to touch it. run a welding rod for 10 seconds and see how hot it gets. i used to wreck buildings, so i know a few things about it.

ever hear of the 'abuse' button?

[deport]

BTTT........