psikeyhackr said:
My hypothesis for why I am wrong? Why would I have such a hypothesis?
I think you misread. The hypothesis I'm referring to is an hypothesis for why colleges are not "all over this". That's been my main focus here: you are claiming that there are big questions that need to be answered, but most people - particularly the people who you most want to address them - apparently do not agree. So I want to know if you've considered why the very people who you think should care about this appear not to.
It does seem like you do have an hypothesis:
But after 13 years the engineers have a problem. Because if it could not happen then they should have figured it out long ago.
So you hypothesize that a vast conspiracy involving every engineering student (even those who were 8 years old at the time of the attack) and practicing engineer in in the United States (the world?) is responsible for the apparent lack of interest? That's just plain nuts. You should consider the possibility that the face-value explanation really could be the right one because such a conspiracy really isn't possible.
I
am an engineer working in the construction industry (I do mechanical engineering but have dabbled in other disciplines) and while I don't really see much value in any of this, I will still comment on this:
psikeyhackr said:
With no fire ever having brought down a skyscraper before? Admittedly none had been hit by airliners before...
So, yes, obviously you already know that your objection is invalid since you gave the correct answer as to why right after saying it. But the background is interesting.
One Meridian Plaza was a 38 storey hi-rise in Philadelphia that was built in 1972 and was destroyed - but not felled - by a fire in 1991. At the time it was the 3rd tallest destroyed building in the world and the only one destroyed by fire. It is the only close relative to the WTC collapses.
Due in large part to this fire, all hi-rise buildings have automatic sprinklers today and the WTC did in 2001. The fire in One Meridian started on the 22nd floor, but only one floor, the 30th, had sprinklers (installed by a tenant). Ten sprinklers on that floor stopped the fire and it burned itself out. Firefighters had been recalled due to fears that it would collapse. Later, it was determined:
wiki said:
By February 26 city officials had determined One Meridian Plaza was not in danger of collapse.[11] There was structural damage to horizontal steel beams and floor sections on most of the fire damaged floors. Under extreme fire exposure the beams and girders sagged and twisted and cracks appeared in the concrete floors. However, the overall structure was stable and able to support the weight of the building. Thermal expansion of the steel frame caused some of the granite panels to be dislodged from the building's facade.
http://en.wikipedia.org/wiki/One_Meridian_Plaza#Replacement
Suffice to say, the obliteration of much of the contents of the floors that were impacted by the planes left the WTC sprinkler systems compromised.
Lessons learned?
1. Major fires in hi-rise buildings are very rare and even more rare today because pretty much all major hi-rises have sprinklers. So a fire like the One Meridian fire is all-but impossible today. And an argument from a 9/11 "truther" that 'gee, it's never happened before' is clearly both wrong and irrelevant.
2. Hi-rise buidings are made mostly of steel and concrete, which don't burn, yet the contents of the office building were able to cause irreparable structural damage to the building. All arguments about the heat of a jet-fuel fire are red herring distractions: even a wood/paper fire is enough to structurally damage a building and whatever the temperature in the WTC, suffice to say, it was hotter than in One Meridian.
For the next part of your post:
...but how does that explain tons of steel hurled hundreds of feet from the towers?
As bizarre as it is to lump together in one sentence two completely different issues, this one is silly enough on its own that I'm wondering if you stuck them together for a strength-in-numbers type of game.
Anyway, this is an obvious one: when a column is compressed vertically so it bows horizontally and then snaps, all of the released elastic energy is released horizontally. You can try this with a brittle object (be careful!) such as a stick or some types of CDs. When you compress it vertically and it snaps, shards of it will shoot across the room.
Beyond that, of course, is simple probability: there is a lot of random motion in a collapsing building and a certain fraction of it is going to push objects horizontally. I'm sure there is a probability function for the % of mass of the building that falls in certain radii from it, but when the building contains thousands of tons of material, it isn't a stretch for some of that random motion to throw some tiny % of material a few hundred feet. Especially considering that for an object fired sideways from 600 feet up, it takes about 6 seconds to reach the ground, which means it only needs an initial speed of 50 ft/sec to reach a distance of 300 feet. That's pretty slow for the energies involved.
Again: neither of these issues should seem peculiar to an engineer, so they both fit my "not interested" hypothesis. Few engineers would be interested in proving something so obvious and mundane. But again: what's your alternate hypothesis for the apparent lack of interest among engineers?
