POLITICS: Physics Prof Says Explosives, Not Fires Brought Down WTC Towers

Originally posted by Shadow88
intellent persons

Originally posted by Shadow88

The scientist on which the topic surrounds himself stated that basic physics tells him there had to be some other factor.

Originally posted by Shadow88

An aluminium plane connot take down a building of that size, that is just any intellent persons common sense,

Originally posted by wecomeinpeace
I find it interesting that NIST did not take into account two things that have a bearing on any conclusions arrived at based on these images. One is lens distortion, and the other is light refraction due to heat.

And look at this car driving over a hot road:


It seems that the wheels on this vehicle are grossly out of shape. Quick, call NIST and let them know there's an impending car crash they may need to investigate!

Does this prove that there was no column bowing at all and that it was all due to lens distortion and light refraction from heat? No. Does it indicate that the column bowing was likely not as pronounced as NIST would have us believe from these photographs? You betcha.

Originally posted by MacMerdin
BTW, the inner core columns WOULD act like trees...thats what they essentially are is steel trees....a tall straight object that is larger at the base and smaller at the top. These columns would topple at the cap NOT dissintegrate IMO.

Originally posted by HowardRoark
So where was the pavement in front of the WTC in those photos?

You do realize that the refraction effect is caused by the hot pavement, don’t you?

Originally posted by HowardRoark

How would the columns withstand the lateral forces put upon them as the building collapsed?

Do you know how the WTC towers achieved lateral resistance from wind pressure?

How was this different from a conventional box girder type structure?

Originally posted by ANOK
It doesn't work like that. When an object falls on a simular object, lets say 2 bricks, the lower brick is not gonna give way with no resistance.

In the WTC you had bricks faling on bricks not bricks falling on hands.

If the lower floors were equaly weaker than those above then yes maybe you would get what you're saying.

Source
After Corley was named to head the Trade Center investigation, there was some grumbling among steel industry leaders because the Skokie engineer is known as a specialist in concrete. The steel people fretted that Corley would blame the collapse on the steel frame of the Trade Center towers and say that structures that relied more on concrete, such as the Petronas Towers in Malaysia, currently the world's tallest buildings, would have fared better.

‘They showed us many fascinating slides’ [Eaton] continued, ‘ranging from molten metal which was still red hot weeks after the event, to 4-inch thick steel plates sheared and bent in the disaster’. (Structural Engineer, September 3, 2002, p. 6; emphasis added.)

The observation of molten metal at Ground Zero was emphasized publicly by Leslie Robertson, the structural engineer responsible for the design of the World Trade Center Towers, who reported that “As of 21 days after the attack, the fires were still burning and molten steel was still running.” (Williams, 2001, p. 3; emphasis added.)

Originally posted by HowardRoark
There were a number of lateral forces. The wind, although it was light that day, would have exerted some lateral pressure. More importantly, as the floor trusses heated and began to sag and fail, the forces that these structural members exerted on the columns changed from vertical forces to lateral forces. This is what caused the exterior walls of the towers to bow inward shortly before the collapses.

Once the collapse began, there were plenty of lateral forces on the structural members as they buckled, twisted and sheared under the force of the falling weight of the building. To suggest that they would have done anything else is just silly.

There is plenty of information in the NIST reports
wtc.nist.gov...

The lateral stiffness was provided by the exterior columns. This is different from most conventionally framed building where wind bracing or masonry walls in the core area provide the lateral stiffness.

Once the exterior walls buckled, the core would not have been able to support the loads imposed upon it. It too would have failed.

As for the NIST calculations, you can always write or e-mail them. I think that they used some pretty heavy duty software and hardware to run the models, however.