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Leaked FEMA/ASCE Draft Report On WTC Collapse
securitas writes "The New York Times obtained a copy of the World Trade Center draft report by the Federal Emergency Management Agency and the American Society of Civil Engineers about the engineering failures that caused the towers to collapse. Among the findings: 'Fireproofing, sprinkler systems and the water supply for hoses were all disabled and the fires generated heat equivalent to the energy output of a nuclear power plant' reports the NYT (Yahoo link). Amazingly, if it wasn't for the fire (or another secondary catastrophic force), the towers would have remained standing."
if it weren't for the 767s, massive fires, tens of thousands of gallons of burning jet fuel, and the abliteration of the several floors worth of the buildings' structural cores, the towers would have remained standing. But, shhh, this is leaked info. Don't tell anyone.
I recently watched a well known (in the UK) documentary series called "Horizon" on the WTC disaster. It basically stated in no uncertain terms that the disaster was caused by the use of drywall for all the fireproof walling. The theory was that the explosions caused by the planes basically blew away the drywalling and so the heat from the flames which would have otherwise been slowed down by the drywall, would have been dramatically slowed down.
I wasn't sure whether to entirely believe the program or not, but it seemed fairly plausible. However I came away asking only one question: "So what would have been better?"
Matt. Want XML + Apache + Stylesheets? Get AxKit.
I think most of us in the construction industry (architecture) were concerned about this as events were unfolding, even before the first tower collapsed. But the saddest part was finding out later that concessions had been made during design/construction in the sizing and configuration of sprinkler systems including the abscense of a rooftop water supply.
Who knows if it really would have helped, but having to second guess now is hardly comforting. As in most things, those that focus on stupid quantitative evaluations of design (cost per square foot for example) are doomed to come up short when all the chips are really down.
There is no need to use a SlashDot sig for SEO...
Pity that:
- The WTC was a public building only "sold" a few months prior to the attack. It was built and owned by the Port Authority of NY & NJ.
- There are likely no other buildings in the world (possibly excepting the Great Pyramid) that could have held up as well/as long to the assault as the WTC did.
So 2 for 2 you were wrong; now please crawl back to your dark corner.I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
One of the contributing factors is the lack of Asbestos fireproofing above the 70th floors. New EPA laws were enacted during the construction of WTC that prohibited the spray-on fireproofing that was applied to the I-beams. With the fireproofing, the I-beams could withstand an esimated 2000 degree fire, and without they would lose temper and bend at approx. 1200 degrees.
The jet fuel burned at an excess of 2000 degrees,
so it's likely the towers still would have collapsed, but some extra time would have allowed further evacuation efforts.
Burning kerosine swims on water. No sprinkler system would have put out that fire. Halon would have been needed, but this surely would have been too expensive for the whole building to be equipped with. Nevertheless it surely would have delayed the colapse for a certain time if the sprinklers had worked and cooled the fire.
The report seems not to say anything about the fact that the WTC was a steel construction and thus rather unprotected against fire as opposed to ferroconcrete which is safer but would have needed the buildings to be smaller. This is the cause why there are not similar high buildings in Europe where regulations demand ferroconcrete.
Perhaps you could take your anti-capitalist rhetoric elsewhere, comrade. If you had any decency, you'd know that in the time period the towers were designed and constructed in they were paragons of efficiency and safety. Far from cutting all costs and maintenance, the towers were meticulously designed to withstand all manner of natural forces, fires, and other disasters. They were even designed to withstand the impact of a fully loaded 707 jetliner, the largest then available. Alas, a 767 is much larger and carries more fuel. Even then, the towers would have stood had it not been for the fire, and the impact and explosion were far more than any designer could've ever dreamed would happen.
My friend, you appear to have a huge chip on your shoulder that is clouding your judgement. People died because madmen hijacked two jetliners and deliberately slammed them into skyscrapers full of thousands of innocent human beings. Corporate greed and stockholders had nothing to do with it, and it is callous, irresponsible, and shallow of you to even suggest such a thing to further your obvious hatred of corporate America.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
In the future, we'll just have to build all really tall buildings underwater. Maybe Kevin Costner could offer up some good advice.
He stated that the airplanes could have not brought them down seeing that buildings of a lesser, equal, or greater size get the same sort of impact daily with the force of winds.
Well, this may be true, but when you consider that the airplanes *did* down the two buildings, one must realise that there is something flawed about that statement. I would accept that most skyscrapers are pummeled with the strength of an airplane crash daily, except that the force is spread across the entire structure, or at least one entire face, of the building. Consider what it might feel like if you were walking down the street and suddenly the entire energy of the ~50mph wind gusts that you normally can easily withstand were channeled at a 1cm^2 section of your chest, or even your skull. Wouldn't that at least completely knock the wind out of you? I haven't the time to properly do the math myself right now, but it may work out that such an energy release over such a small space would be enough force to pierce skin and possibly break bones.
And that is what made the difference, aside from the fire and explosions that are discussed elsewhere in the thread.
They ran an hour long program where they interviewed two key people ... the mechanical engineer who built the towers and a forensic mechanical engineer who was looking at the wreckage.
Each had unique viewpoints. The designing mechanical engineer is haunted to the core over this. Most of his sentances trailed off as he was reliving what happened.
The forensic scientist identified the fact that the fireproofing material was blown off from the original impact. This hastened the collapse. He also commented that the support structures for the floors were the first things to fail.
My question is did anyone really think they were going to fall? Remembering back to the day no one in the media raised the question. None of my friends or family I was talking to that day even thought of it as a remote possibility.
This raises a very interesting question about our expectations vs. reality. After the shuttle disaster I think this stands as one of the most shocking slaps in the face to us concerning technology.
Of course the buildings weren't going to survive, but our faith in technology made us think that day that the buildings collapsing wasn't a possibility.
Think for a few moments before posting.
- These buildings received Certificates of Occupancy, had been tested in the prior attack, their systems and procedures were as good as any other in the world.
- There is NO evidence of cost-cutting, sub-standard materials or equipment, etc. This was a public building owned until recently by the Port Authority of NY & NJ and by all reports kept in exemplary condition.
- These were not slip-shod towers built overnight in some 3rd-world country without reviews, standards, or regular inspections.
- Aside from their unusual tube-design (which appears to have been their greatest asset) and height there is nothing special about WTC towers that would separate them from tall buildings around the world. This includes materials.
Finally, before you post realize that 3,000 humans died horribly in this disaster. Perhaps before you post your Monday-morning-quarterbacking, rumor-spreading & conspiracy theories you might show a bit of respect for those folks and the ones they left behind.A little courtesy and respect is appreciated.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
For that reason entirely, the towers actually did have water tanks up on the 100th floor for putting out fires. Witnesses describe water rushing down the stairways. So in some way, they were prepared for this sort of thing
El Karma: excelente(principalmente la suma de moderación hecha a los comentarios de los usuarios)
Didn't stop Cameron making up details (and lots of them) for "Titanic"; how long does something have to be in the past before no one cares I wonder. Probably a question Yassir Arafat is asking himself about now...
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
Another famous New York Landmark also suffered an airplane collision. Now granted the airplane that hit the side of the Empire State Building was not the same size as the two that hit the World Trade Center, the B25 did quite a bit of structural damage. Enough damage in fact, that if simply the collision caused the Trade Center collapse, then the Empire STate (the plane did hit somewhere between the 78th and 79th floors)building should have also collapsed. In actuality the reason that the Trade Center collapsed and the Empire State building did not, is one of metallurgy. The thousands of gallons of jet fuel that were burning in the Trade Centers got hot enough to anneal the structural steel. When that happened the sheer mass of the floors above the impact zone collapsed triggering the chain reaction. Had the Jets that hit the Trade centers been nearly empty of fuel (ie. getting ready to land, instead of just taking off) the buildings would have survived the impact.
The following excerpt is from "Empire: A Tale of Obsession, Betrayal, and the Battle for an American Icon", copyright © 2001, available from John Wiley & Sons. It describes the impact of the B25 that hit the Empire State Building in 1945.
"Army Lieutenant Colonel William Smith Jr., a 27-year-old veteran of 34 bombing missions over Germany, had been flying a twin-engine B-25 bomber from Bedford, Massachusetts, to New York's LaGuardia Airport, and had secured permission to continue to Newark, New Jersey.
The fog was blinding. When he dropped down out of the clouds, he found himself approaching a forest of skyscrapers. In a panic, he banked away from the Grand Central Building, then from another tower on Fifth Avenue, only to find himself bearing down on the biggest one of all.
In desperation, he pulled up hard, twisting. The 10-ton (9-tonne) bomber plowed into the office of War Relief Services of the National Catholic Welfare Conference on the 78th and 79th floors, 913 feet (278 meters) off the street, tearing a gaping hole in the Empire State Building's north side."
The full article describing the impact in 1945 can be found here: Empire State Building Collision.
The WTC was designed to withstand the impact of the largest airliner of its time, a Boeing 707. A 757/767 isn't much more massive than a 707, but obviously the real problem is the tremendous amount of fuel that a cross-country flight carries.
In fact, it probably wouldn't have mattered what fire suppression system the building used...jet fuel is basically kerosene and it is much lighter than water. You can't effectively extinguish a kerosene fire with water. That's why you see aviation firefighers using something called aqueous film-forming foam. It floats on the kerosene.
Maybe to the layman the fact that the buildings survived the impact was amazing, but in fact it was simply a matter of good, purposeful design. Unfortunately, it's asking an awful lot to expect structural steel to survive the kind of intense temperature that is generated by an aviation fuel fire, particularly when the fuel supply is effectively limitless.
-h-
Calling the WTC's collapse an engineering failure is kind of like taking C4 to slashdot's servers and saying that the code failed somehow. You just can't reasonably have expected them to anticipate this. Expecting a building of similar requirements (e.g., height, usable space, windows, etc) to withstand both the impact of a modern airliner and the jet fuel may well be an impossible task, especially when trying to do it within any reasonable budget. Please think about what you are saying and try to be a little less arrogant. Thank You
16 days after Sept 11th, I received this in an email from my father, (who happens to be a Mechanical Engineer):
- Professor Thomas Mackin, who currently teaches Failure Mechanisms in Engineering Materials class, made this short presentation (attached) after the World Trade Tower tragedy. This presentation was made in response to the
Chancellor's request for teachers to discuss with their classes the recent events. Mackin was clearly as shaken up about the events as were the rest of us. He only had a short response to his final question: "As engineers, what can we do to prevent this from happening. - Nothing."
There was simply too much energy put into the buildings. bin Laden knew that, the engineers know that... it's a damn shame we're back to the accusations, finger-pointing, and blame-placing that so much plagues our culture.Attached was a .PDF file, "ME 346 - Engineering Analysis of Tragedy at WTC."
The engineers did their job. They did it well. World Trade Center 1 & 2 were good buildings -- I stood on top of one just over 10 years ago. I can hardly believe I never will again.
Osama bin Laden and his cronies are the ones -- the ONLY ones -- responsible for this outrage. Please, let's try to remember that.
"...America's great minds of today, teaching America's great minds of tomorrow. Poor bastards." -- A Beautiful Min
...the report more or less concludes that the buildings collapsed because of the way they were designed, but withstood the damage for as long as they did before collapsing because of the way they were designed. Talk about, "Damned if you do, damned it you don't."
The worst-case disaster scenario for those towers was a 707 accidentally blundering into one, not a bunch of crazy religious-zealot, martyr-wannabe motherfuckers purposely plowing a much larger, fully-fueled aircraft into it at full speed.
If anyone who lost someone in the collapse even thinks of trying to sue anyone involved in the design or construction of the twin towers, they ought to be drawn and quartered. Sure, they could build a building that could stand up to worse than the WTC got, but proofing it against everything would cost a mint and leave a few phone booths' worth of usable space per floor. Don't forget that there wouldn't be any windows. The rent would be so expensive that nobody would be able to afford to put an office in it.
IMHO, when you step back and look at the big picture, you simply cannot fault the design of the buildings for the fact that they catastrophically failed in the face of an unprecedented, unimagined, deliberate action that was well beyond the scope of their design.
~Philly
Chip? No, I just can't stand to see people mouth off on things they either (a) have no knowledge of or (b) can't back up anyway. I will address your points in order:
1. Corporate America built the towers and staffed them. SO? Buildings are built and staffed all over the globe by billions of people every day. What is your point?
2. Since when does corporate America "label" anybody anything at all? Did Cantor-Fitzgerald "label" those poor Muslims something they didn't like? As last I recall, the only people that like to "label" anything these days are spinmeisters, talking heads, and religious zealots. Either way, that has no bearing whatsoever on the involvement of corp. America in causing the towers to be attacked. Proclaiming otherwise is like saying a rape victim caused her rape because she was female (i.e. an obvious target).
3. Market demand indeed. The one failing of capitalism that I routinely hate is that it sometimes bears a striking resemblance to a parent and child. If the child (i.e. consumer) wants something from the parent (i.e. the market), the child doesn't want to be told "no", and does not understand why some things are better that way. Consumers want to have their cake and eat it, too, and many businesses (and governments) do not have the gonads to deny them what is clearly not in their best interests.
That being said, airline passengers KNEW the ramifications of the security lapses, or if they didn't they should've taken the time to find out as all the reports are in the public domain. I place a very high value on my own skin as I am quite attached to it, and I don't take such matters lightly. Airlines had tried levying increased fees for increased security, and passengers voted with their wallets. It's sad, but in many ways they got what they asked for. They had a choice, and the majority chose wrong. Learning lessons can be painful sometimes -- just ask any child.
4. Corporate America has lobbied heavily? While this is true, it pales in comparison to what the past presidential administration lobbied for. Democrats would even like to see illegal immigrants allowed to vote, for crying out loud -- alongside convicted felons and the mentally insane. Please note I'm NOT a Republican, as I have no taste for their spinelessness. I'm Libertarian, but back to the chase...
"Anti-capitalist" can be taken how you like, insult or not. But to be against capitalism is to be blind to the very forces that make your daily life possible. The car you drive, the phone you use, the business you work at, the computer you work on, the Internet itself -- all of it has been created for, by, or as a result of corporations and capitalism. It is not perfect, but it is the best thing humans have come up with so far. All other forms of government have either failed (Communism, Socialism) have encroached on personal liberties (Monarchy), or brutally supress their own people and dissidents (Despotism, Religous Oligarchy). When someone comes up with a system of government that rewards hard work AND takes care of those that choose NOT to work as hard, I'll reconsider, but until then, Capitalism is (IMHO) the best thing going.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
If I was a terrorist, I would hijack a 747 cargo plane. Lots of potential for causing damage and no passengers to deal with.
Mea navis aericumbens anguillis abundat
For many of us, South Park notwithstanding, still feel every day the loss of friends & lovers & family to that disease. Furthermore many of us watch yet more friends, family & lovers continue to fight for their lives, every day.
That many somehow believe that the epidemic is over or that they are somehow safe from it is only more disheartening and even more tragic.
So unless you've lost ones close to you to HIV, or to the events of September 11, 2001, please don't take it upon yourself try and tell the rest of us what we should find "funny" or not.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
In the History Channel's WTC documentary, they showed large backup generators whose purpose was to briefly power the entire complex in an outage. There were also large tanks of diesel fuel to supply the generators. I'd say it's likely that setup was in 7 WTC or one of the other ancillary buildings.
And now a quick Google search reveals this: Engineers Suspect Diesel Fuel in Collapse of 7 World Trade Center.
~Philly
What I am trying to say is that the people who are thinking "the sprinklers couldn't have been expected to put out the fire because jet fuel was keeping it burning" and "the building collapsed because the fire was especially hot from the burning jet fuel" are wrong, because the jet fuel was gone long before the building collapsed. The sprinklers had a chance to put out the fire after the fuel was gone, but they didn't. The heat that caused the collapse came not from jet fuel, but from combustion of ordinary items. The argument about directness was only tangential to my real point.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
The existence of the jet fuel, in the few seconds for which it existed in the fire, assured that the fire would be unstoppable and most definately not of the ordinary nature that one could expect a firefighting system to be able to stop.
It's not "Fuel fire -> ordinary fire -> collapse, as you claim. It's "Fuel fire-> really huge gigantic fire in an instant with every flammable material available in flame all at once, which would not normally happen in a normal fire -> collapse.
Don't label something "offtopic" unless you know the topic well enough to tell what's on topic.
Built in a rush before WWII.
In a swamp.
On pilings.
W/O word getting out.
To this day.
Riiiiight. It's where they hide "The Greys".
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.