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Do you believe there is a U.S. government cover-up surrounding 9/11? (pg. 56)
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| pkcRAISTLIN |
| quote: | Originally posted by _Ocean_Drive_
You're very selective in which engineers you believe. There are 'experts' on both sides of the story here, but you're only believing the ones who you WANT to believe. |
not true. im not sure the 911 movement has any structural engineers as part of their theories. you do have steven jones, but he's not qualified, and his paper has been torn to shreds by engineers world wide.
whereas i have pretty much the entire engineering community worldwide. the list is as long as my arm. good enough for me.
| quote: |
Their most famous member, and co-founder [of scholars for 911 truth], is Steven Jones, a physicist at Brigham Young University. He has become famous for publishing a paper on the WTC collapse. Thus far this paper though, has only been reviewed, not in a journal on physics, or structural engineering, but in a Marxist journal of political economy. BYU itself has rejected his work. Dr. Jones primary research has been, not in structural engineering or the reaction of metals to heat, but in cold fusion, which even in the physics community is regarded as bordering on alchemy. Even more bizarrely, his other famous published work was one right out of the World Weekly News, claiming that Jesus visited Central America based on ancient Indian artwork...
I compiled the list of members and categorized them by specialty, position and institution, which actually was rather difficult. Oddly enough many of the members don't list their qualifications or university, which is quite strange, since every professor I have ever met is more than happy to go on for hours about their academic credentials.
I came up with a list of 76 members, expecting it to be full of Ivy League engineers and distinguished Middle Eastern scholars, experts bent on proving that the US government, and not Osama bin Laden attacked the World Trade Centers. I was wrong.
Out of the 76 "experts" the most common academic discipline was philosophy, with 9 members, including a co-founder. Since 7 members did not even list an academic discipline, this was 1/7 of their credentialed membership. English/literature and psychology came in next with 5 members each. Even theology and "humanities" came in with 4 and 3 members respectively. Among actual scientific fields, physics was way in front, with 5 members, including the aforementioned Dr. Jones. I am not sure as to their academic credentials though, at least one of the "physicists", Jeffrey Farrer, isn't even a professor, he is a lab manager at BYU. One has to wonder whether Steven Jones' janitor is also listed as an associate member?
So how many engineers do they have? Out of the 76, a grand total of 2. Jean-Pierre Petit, a French aeronautical engineer, who despite the obvious handicap of being French actually seems to have a relevant qualification. Curiously enough though, he doesn't seem to have written a single word on 9/11. He has written though, on a mysterious plot by the US military to bomb Jupiter with anti-matter weapons!
The second engineer is Judy Wood, who has been mentioned in the comments here for her bizarre billiard ball from the top of the World Trade Center theory. OK, Ms. Wood is an actual Mechanical Engineer at Clemson, but thus far her work has been primarily focused on the stresses of dentistry. A fascinating field no doubt, but hardly relevant to planes crashing into buildings.
So how many structural engineers are listed? Absolutely zero. How many experts in Middle Eastern studies, or the Arabic language? Also zero. But they do have a professor of social work! |
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to be fair, these members might not represent the entire 9/11 movement, but id suggest it would be a fair chunk. certainly many of the theories have been propogated or created by this particular arm of the movement. speaks volumes imo. |
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| colonelcrisp |
dont have much time today ladies but ill throw some info your way.....
while the whole kinetic vs potential energies theorys are very valid as it is the foundation of modern phisics..... your forgetting about one of my favorite newtonian laws...... impact and momentum.
facts frist, buildings collapsed from the top down...... therefore any explosives would have had to be detonated from the top down as well..... these would not have spiked a sisemograph (spelling) as the building resonance would have absorbed the shock wave energy well before hit hit ground level... structures resonate at harmonic frequencies with wind, load shifts etc, so a large blast wave would get absorbed by the structures frame.
now you want a real explanation for the sizemic spikes (sorry spelling bad today) according to newtons law of momentum and impulse the force generated by an impact is a function of homogenous mass and velocity. wehn the building started to collapse, its not hard to see that it turned to a big ball of dust rather quickly. meaning that the concrete was failing at an alarming rate. the first couple floors would have been the only ones to fall completely intact, meaning the most homogenus mass impacting at one time. by homogenus i mean that the floor slab was most likely in one piece still. here is an analogy. lets take a ford pinto ok and tie it to a long rope and swing it at a brick wall.... it will do alot more dammage than if we were to take the same car, cut it in half and swing both halves individually at the wall... While the entire mass of the building did fall, larger sections such as floor slabs would have caused alot more damages than fractured pieces of concrete etc.
without a time syncronized video of the colaps with the sismographic readouts, all i can do is make an educated guess. and my guess is that the first 2 or 3 floors collapsing caused the spike since most structures are harmonically ridgid on teh vertical axis. such an impact would have sent and impulse of energy right into the pile foundations which would create a significant sismographic reaction. |
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| shaolin_Z |
| quote: | Originally posted by pkcRAISTLIN
its interesting you view your arrogant & condescending tone so very differently from my abusive posts ;) |
Show me a single occasion where I used language like that specifically to describe or mock you (and so obviously directed at you personally):
| quote: | Originally posted by pkcRAISTLIN
i passed elementary logic when you were still in highschool you arrogant , so you can suck my dick. |
I was annoyed as hell, since you demonstrated a complete lack of understadning of elementary physics and went as far as to say that the fundamental laws of physics did not apply. Most people don't end up taking a single course in formal logic in their lives so it's wasn't unreasonable for me to conlude you'd be unfamiliar with that to, and even those that do, I've known many of them who haven't the slightest clue what they're talking about.
And you really haven't said a single thing here that would make any (big or small) holes in my argument. You're just stating "I don't believe that those are the implication of the different seismic readings." Well, that's too bad. Even your buddy colonelcrisp conceded to an unusual seismic reading difference and it's implications for total energy in both collapses, although he atleast tried to give an alternate explanation. Which I don't find convincing for such a huge difference (virtually double).
And your request for help only convinces me even further that you can't argue anything related to this subject on your own. Have fun copy pasting material or have someone else argue for you.
EDIT:
| quote: | Originally posted by pkcRAISTLIN
if this evidence was so clear-cut, then i doubt its revelations would be ignored by the world's engineers. |
It's negligence of glaring anomolies like that (not just the scientific aspect of 9-11) that makes it extremely hard for me to take any pro-no-govermental-involvement arguments seriously at all. This certainly isn't the only example of it and I posted that just a couple pages ago. If you want to aruge a position, you have to consider all the evidence. The insant you do take it into considertaton, it esposes their argument for what it is, a house of cards.
EDIT2: Like ignoring these for example:
| quote: | Originally posted by shaolin_Z
Prior knowledge of attacks? FACT
Failure to take any action (let alone effective action or preventive measures)? FACT
Unusual change in chain of command and interference with standard NORAD protocols resulting in attack on pentagon that would never have happened if standard procedures were allowed to take place? FACT
Seismic data consistent with controlled demolition theory? FACT
Expansion of excecutive branch and tyrannical bills/law butchering constituionaly guaranteed protection from state and abuse of power? FACT
Clear abuse of power and convicted criminals appointed in key governmental positions? FACT
Illegal and unwarranted domestic spying on grassroots organizations, peace groups, and political advesaries? FACT
War based on blatant lies and deliberate manipulation of intelligence considered faulty by agencies in the first place and produced under pressure from executive branch? FACT
Feel free to add to the list guys.
EDIT: Some more additions to that list:
Illegal destruction and removal of forensic evidence from crime scene? FACT
Executive branch blocking independet investigation into 9-11 and 9-11 commission only being formed after families of victims pressuring the Government? FACT |
Collectively, they're absolutely devastating to the arguments for no Goverment complicity. But I already expect you to ignore all that, just like you did my recent argument, which is why you don't have much credibility in my eyes.
EDIT3: Something else I forgot to address:
| quote: | Originally posted by pkcRAISTLIN
you mentioned it on several occasions from memory. and its a ty comparison, as myself and colonel & occ showed you. you simply cant compare the two structures. its intellectually dishonest. |
No it isn't. And I'll spell it out for you since your preconditioned mind seems incapable of comprehending it. Precendence shows that steel-frame high rises do not fall due to plane crashes or fire. The WTC was specifially designed to be able to withstand all that. So I would need a compelling reason to believe that it did fall for those reasons, and the pancake theory, even according to FEMAs reports, ONLY HAS A LOW PROBABILITY OF OCCURANCE!!! Now do you see why I brought it up and am incredibly reluctant to accept it as a plausible explanation? EDIT4: Especially given the incredibly short time span between being hit and prior to collapse (102 minutes for WTC1 and 56 minutes for WTC2, according to Wikipedia)? And according to NIST's final report, p. 33, WTC1 was "recuded to rubble" in approximately 12 seconds (and according to them, the time for total collapse convinietly ranged from 15 to 25 seconds, but this was "hard to determine" :rolleyes: ). I'm going to work with WTC1 was 1,368 feet (417 m) high (source: World Trade Center, New York City. Emporis. Retrieved on 2006-04-13, ignoring the height of the antena, another 110 meters). An object in freefall would take 9.22 seconds to reach the ground from the top (ignoring air resistance).
[ (v^2=u^2 + 2ax) , (u=0 m/s), (a=g=9.8 m/s^2), (x=417 m), so (v = 90.41 m/s), and (x= 0.5*(v + u)*t), t = 9.23)] You expect me to believe that the resistance offered by 109 floors (discluding the top floor, 110) pancaking would cause WTC1 to collapse in only 2.77, 5.77, and 15.77 seconds more than freefall speed (asusuming each time interval of 12, 15, and 25 seconds)? That means it took 0.025, 0.052, and 0.143 seconds on average to get past each floor?!?! That's all the resistance offered by all floors combined and the air? Let's not forget that according to FEMA, the pancake theory had only "a low probability" of occurance in the first place. So somehow, something with an extremely low probablity occurs, and then sprectacularly in an incredibly short time period as well, with twice the amount of total energy in the first instance. Yeah, keeping everything in mind, that sounds incredibly believable to me :rolleyes:. |
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| shaolin_Z |
| quote: | Originally posted by LazFX
Pssst... the one thing the guy from land down under is not,
much respect for pkcRAISTLIN, I have do I..
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So you have "much respect" for people who post other people's material and analysis, and present them as their own arguments? And the moment they have trouble with something (quite simple IMO), they respond with empty rhetoric and get someone else to argue for them? |
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| shaolin_Z |
You also failed to respond to this:
| quote: | Originally posted by shaolin_Z
Show me a convicing statiscal comparison of steel-framed high rises that collasped on themselves and and one's that didn't where controlled demolitions were not the case, suggesting a likely probability of occurance in the case of the WTC.
EDIT: Perhaps then I'll take the pancake theory more seriously. |
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| colonelcrisp |
ok shaolin i just did some more reading on this topic, and i spoke with my geotechnical mechanics proff this afternoon as well. ok here it goes
both towers had an approximate mass of about 500 000 tons (metric)
i would like to point out that the TNT vs seismic response analogy is to quanitfy the energy capacity. its not a literal comparison to explosive force
seismic measurement and reading is not only a factor of energy but also of time. for instance 1 million joules of energy released or imparted to the ground over a micro second will cause a seismic response far greater than 1 million joules of energy released over 1 second.
a richter reading of 2.1 corresponds to aprox 8.91x10^14 Joules of energy where as a reading of 2.3 is aprox 1.77x10^15 hardly a factor of 10 difference ps energy calculation of richter readings is
Log(E) = 11.8 + 1.5M
where M is the magnitude and E is the energy released in Joules
now as the colapse of the tower that generated the richter of 2.1 was two seconds longer than the collapse of the tower that generated the richter reading of 2.3. I think its pretty clear that the seismic difference can be explained by impulse, which of course is the amount of energy transfered over a period of time. |
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| shaolin_Z |
| ^^ Thanks for the promt response and your effort, and for mainting a civil dialouge. I'll look into your response and reserach a little deeper to figure out any possible flaws/counter arguments, and the probability of occurance. |
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| shaolin_Z |
| quote: | Originally posted by colonelcrisp
i would like to point out that the TNT vs seismic response analogy is to quanitfy the energy capacity. its not a literal comparison to explosive force
seismic measurement and reading is not only a factor of energy but also of time. for instance 1 million joules of energy released or imparted to the ground over a micro second will cause a seismic response far greater than 1 million joules of energy released over 1 second. |
Fair enough, atleast for now I suppose. But there should still be a proportional relation between energy capcity and PE (and hence KE). It's still the best indicator for comparison (regarless of actual quantificied values, since we're considering a ratio).
And doesn't a million joules (10^6) pale in comparison to a minimum of the two values for energy capacity of the towers, (8.9*10^14) which is approximately equivilant to (10^15)? X*(10^6) joules of energy would be an additive variable as opposed to multiplicative (not sure if I used the proper terminology there, feel free to correct me). Even under the assumption of X*(10^6) joules per micro-second (10^-6 seconds) and a relatively uniform distribution of over the time period of a single second, that wouldn't be any greater than X*(10^12). As an additive variable to (10^15), it still shouldn't result in a significant change to that quantity, especially in the case of 1.77*(10^15).
I guess I should add that (10^6) joules is a fairly significat quantity of energy to be released in a micro-second, one I'm not so inclined to arbitrarily assign as a coefficient to energy release in joules per micro-second as it uniformly distributes to (10^6) times greater in magnitude uniformly spread over a second. So you are correct in asserting a far greater mangitude of force released or imparted to the ground with that assumption, but what I'm questioning is the probablity of such a large coefficient for energy dispursed in a micro-second. Even working with that assumption, it's an insignificant additive variable to (10^15).
Plus, the difference between 1.77*(10^15) joules and 8.9*(10^14) joules is 8.8*(10^14) joules, far greater than X*(10^12) joules.
| quote: | Originally posted by colonelcrisp
energy released or imparted to the ground
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That should factor into KE for the collapsing towers, reinforcing the relationship between the seismic readings and total energy of the two systems, an even stonger indicator of an external energy source.
| quote: | Originally posted by colonelcrisp
a richter reading of 2.1 corresponds to aprox 8.91x10^14 Joules of energy where as a reading of 2.3 is aprox 1.77x10^15 hardly a factor of 10 difference ps energy calculation of richter readings is |
So the ratio of energy for the north tower (WTC1) v.s. the south tower (WTC2) is 17.7 : 8.9 = 1.99 (rounded of to second decimal place, the third digit being 8) which is still approximately 2 (the closest possible value to 2 I might add). It's virtually twice the magnitude, which was my original claim (not a factor of 10, that was a reference to the logrithmic base).
So in conclusion, impulse still doesn't adaquetly account a such large variation in magnitude (2 times greater). |
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| pkcRAISTLIN |
| quote: | Originally posted by shaolin_Z
Show me a single occasion where I used language like that specifically to describe or mock you (and so obviously directed at you personally): |
haha, the comment annoyed the hell out of me. i found it supremely arrogant & condescending. thus my response. alls fair in love n war as they say. respect shaolin, you know that ;)
| quote: | Originally posted by shaolin_Z
And you really haven't said a single thing here that would make any (big or small) holes in my argument. You're just stating "I don't believe that those are the implication of the different seismic readings." Well, that's too bad. Even your buddy colonelcrisp conceded to an unusual seismic reading difference and it's implications for total energy in both collapses, although he atleast tried to give an alternate explanation. Which I don't find convincing for such a huge difference (virtually double). |
well, thats where you and i disagree. i was basically asking you to explain the correlation between the seismic data a little further. because i didnt believe it was that easily transferable, and whattya know!? it sounds as if i was right ;)
| quote: | Originally posted by shaolin_Z
And your request for help only convinces me even further that you can't argue anything related to this subject on your own. Have fun copy pasting material or have someone else argue for you. |
im a political scientist mate, not a physicist. these particulars are well outside my areas of training. so of course i'll ask for help when i feel it is needed. you never go to a book to look something up? well books that can tpye are better still :rolleyes: stop being so pompous. as if your collection of argument is always your own work 100%
and after consulting one of his professors, colonel came up with this
| quote: |
now as the colapse of the tower that generated the richter of 2.1 was two seconds longer than the collapse of the tower that generated the richter reading of 2.3. I think its pretty clear that the seismic difference can be explained by impulse, which of course is the amount of energy transfered over a period of time. |
forgive me, but that sounds an awful like
| quote: |
according to that video shaolin posted, there was a 2 second difference in the times it took each tower to fall. if the same amount of energy is dissipated over a slightly longer period of time, then i would guess that the seismic reading would be different. again, its not my area of expertise but you guys havent answered my question.
the tower that exerted the 2.3 reading fell two seconds faster than the tower that gave the 2.1 reading. |
so i presented you with that hypothesis and you just ignored it. of course it doesnt seem like i can argue my own points if youre just gonna ignore everything i post :rolleyes:
| quote: | Originally posted by shaolin_Z
It's negligence of glaring anomolies like that (not just the scientific aspect of 9-11) that makes it extremely hard for me to take any pro-no-govermental-involvement arguments seriously at all. This certainly isn't the only example of it and I posted that just a couple pages ago. If you want to aruge a position, you have to consider all the evidence. The insant you do take it into considertaton, it esposes their argument for what it is, a house of cards. |
well, is it still a glaring anomaly?
oh, but you're still happy to ignore my requests to put forward an hypothesis for explosives used. youre happy to use the phrase "explosive" to fill in every gap in evidence or explain certain anomalies as if explosives are the panacea for the entire 9/11 movement. but you wont stick your neck out and name a possible explosive will you. ive forgotten how many times ive asked you to do so.
| quote: | Originally posted by shaolin_Z
EDIT2: Like ignoring these for example: |
i didnt ignore them. though some of them are just plain silly. for instance, behaviour after the fact is not evidence of behaviour before the fact. no matter how much you want it to be true, its not evidence of anything at all.
| quote: | Originally posted by shaolin_Z
Collectively, they're absolutely devastating to the arguments for no Goverment complicity. But I already expect you to ignore all that, just like you did my recent argument, which is why you don't have much credibility in my eyes. |
but this just highlights your naivete in how governments actually work. you've tied together all these points in wonderful non sequiturs as if they combine to tell us a story. but they dont. or at least not the story you're reading. "this is what the government has done by using 9/11" DOES NOT EQUATE TO "the government was therefore behind 9/11". just not logical by any stretch of the imagination.
| quote: | Originally posted by shaolin_Z
No it isn't. And I'll spell it out for you since your preconditioned mind seems incapable of comprehending it. Precendence shows that steel-frame high rises do not fall due to plane crashes or fire. The WTC was specifially designed to be able to withstand all that. So I would need a compelling reason to believe that it did fall for those reasons, and the pancake theory, even according to FEMAs reports, ONLY HAS A LOW PROBABILITY OF OCCURANCE!!! Now do you see why I brought it up and am incredibly reluctant to accept it as a plausible explanation? |
find me a skyscraper, that was built in a "tube in a tube" design, that was hit by a big plane full of fuel, that caught fire, whose fire-protection was sheered off by the impact, that didnt collapse :rolleyes: you keep asking these irrelevant questions that make no sense.
how the hell can you cry "precedence" when there hasnt been a precedent in the history of the world? youre beginning to sound ridiculous.
| quote: | Originally posted by shaolin_Z
You also failed to respond to this:
quote:
Originally posted by shaolin_Z
Show me a convicing statiscal comparison of steel-framed high rises that collasped on themselves and and one's that didn't where controlled demolitions were not the case, suggesting a likely probability of occurance in the case of the WTC.
EDIT: Perhaps then I'll take the pancake theory more seriously.
[QUOTE]
see above (for the last time, ive posted on this many many times).
[QUOTE]Originally posted by shaolin_Z
So you have "much respect" for people who post other people's material and analysis, and present them as their own arguments? And the moment they have trouble with something (quite simple IMO), they respond with empty rhetoric and get someone else to argue for them? |
blah blah blah. not ONCE have i ever seen you denounce ogv's or TX's posts that are long-winded quotes from other people. serious double standard from you. and at least i vet what i post, when its very clear ogv does not. not once have i seen you actually take anything ive quoted to task. whether the info is from me or someone else shouldnt really be relevant. the simple fact is you are ill-equipped to deal with it. because you've got nothing.
given this is well outside my areas of knowledge im more than happy with how i dealt with your seismic anomaly. but no, i dont like to get too indepth into things i'll readily admit i dont always understand. no shame in that.
having said that, not one of your CTs have dealt with a single matter ive sourced from elsewhere concerning the collapses. and you keep coming back with the madrid fires or so-called "precedent" when you should know that these points are not only irrelevant, but intellectually dishonest. |
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| shaolin_Z |
Now all of that was my own work. Here's a something I found, since you're so fond of copy pastes PKC:
| quote: |
Disproving the WTC "Pancake Theory" in 110 Easy Steps
The official version of 9/11 in relation to the collapse of the World Trade Center twin towers maintains that after the collapses of the buildings initiated, the structure above the collapse zone of each building (the "caps") fell on the floor below, easily destroying that floor's supports and connections, before moving down to the next, and so on in a chain reaction until each tower was destroyed down to the very pavement. This model includes the seemingly plausible contention that each failing floor added to the falling mass and with each failed floor the velocity of the collapse increased, and hence the kinetic energy grew ever larger and the buildings were doomed from the start; "if one floor failed, they would all have to fail". This hypothesis is affectionately referred to by 9/11 skeptics as the "Pancake Theory", and was first propagated by FEMA and vocal supporters of the official story such as Thomas Eagar[1].
Here, I shall attempt to disprove the Pancake Theory with simple maths and basic physics.
The National Institute of Standards and Testing (NIST)[2] was expected to either strengthen the Pancake Theory with their investigation and report on the collapses, or to produce an alternative explanation. After 4 years and USD$20,000,000 of research, to the surprise of everyone, skeptics and believers of the official story alike, they failed to do that completely. In fact, the institute openly stated that their report "does not actually include the structural behavior of the tower after the conditions for collapse initiation were reached..."[3]
Notable 9/11 skeptics such as Professor Steven E. Jones[4], Jim Hoffman[5], Professor David ray Griffin[6], and others, maintain that the Pancake Theory is impossible as an explanation for the collapses wherein the roughly 15 second time of the collapses from start to finish seems to defy the Law of Conservation of Momentum. In his paper, Why Indeed Did The WTC buildings Collapse?[4], Jones states:
Where is the delay that must be expected due to conservation of momentum – one of the foundational Laws of Physics? That is, as upper-falling floors strike lower floors – and intact steel support columns – the fall must be significantly impeded by the impacted mass. If the central support columns remained standing, then the effective resistive mass would be less, but this is not the case – somehow the enormous support columns failed/disintegrated along with the falling floor pans.
Taking a simple model of the towers, one can show that this is indeed the case, the Pancake Theory is impossible as an explanation for the collapses. Assume a model, in this case WTC1, where each floor was a flat slab simply floating in space, held up by a magical forcefield that turned off as soon as anything touched it. Hence, when each floor collided with the next one below, that floor gave way without any resistance at all. Assume the collisions are perfectly inelastic. In this model, the only thing slowing the collapse is the momentum imparted to each floor below by the ever-increasing falling mass.
Conservation of momentum states that the momentum after each collision is the same as before it, and since momentum equals mass times velocity (p = mv), with momentum, mass, and acceleration due to gravity known, we can calculate the new velocity after each collision, the velocity after each 12 foot free fall (each floor of the tower was 12 foot high), and hence the total time for collapse in this simple model. To avoid calls of bias, I will use close to Thomas Eagar's figures for the mass of the building and cap mass of 500,000 tonnes and 45,000 tonnes respectively while assuming an increase in floor mass in increments across the four major sections of the building.
Model Assumptions:
1. For distance purposes (except for the cap striking the ground), each floor is an infinitely thin slab with all of its mass concentrated into that slab.
2. Collapse initiates at the 98th floor, with the first collision being the cap striking the 97th floor.
3. Air resistance is zero.
4. Resistance from the structure is zero. As in, there are no vertical columns, and no assembly connections.
5. Collisions are "flush" and perfectly inelastic, meaning the falling mass of the cap "acquires" each floor it collides with.
6. None of the mass of the original cap is lost.
7. 30% of the mass of each lower floor is lost over the side of the building and removed from the crushing mass. (Note this only adds 1s to the total time, and 30% is quite conservative when you consider the 236 steel columns supporting 50% of the vertical load were on the skin of the building and thrown outwards, when you look at debris distribution in the satellite pics taken after the event, and when you consider I didn't subtract anything off the 45,000t cap)
8. When the cap strikes the ground, it collapses on itself in resistanceless free fall.
Below is the collapse model depicted graphically:
And here are the calculations:
As you can see, the model produces a collapse time of just over 14 seconds. Remember, this model assumes zero air resistance, and zero resistance from the structure. Furthermore I have used figures of 45,000 tonnes for the cap and 500,000 tonnes for the entire structure, the cap thereby comprising about 10% of the weight. However the WTC towers, as all skyscrapers, were built progressively stronger and heavier towards the base. The cap would therefore be much lighter than 45,000 tonnes, and the 14 second figure would be adjusted up accordingly with more realistic figures.
The collapse of WTC1 took approximately 15 seconds to complete. Add air resistance, the mechanical resistance of the structure, the kinetic energy dissipated in the process of pulverizing the concrete, office furniture, and industrial carpet to average <60 micron-sized dust, and the final expected figure from gravitational "pancake" collapse would be much greater than 15 seconds.
Hence, the US Government's collapse theory would seem to be impossible as an explanation for the collapse of WTC1. This being the case, alternative explanations must therefore be considered and investigated.
Furthermore, I have not addressed above, the issue of the cap being disintegrated into constituent parts as was observed, which meaning that the crushing mass would involve many non-fatal smaller impacts, causing decay in and eventual halt to the collapse. This concept was even openly admitted to by Bazant & Zhou in their paper, Why Did the World Trade Center Collapse?—Simple Analysis:
An important hypothesis implied in this analysis is that the impacting upper part, many floors in height, is so stiff that it does not bend nor shear on vertical planes, and that the distribution of column displacements across the tower is almost linear, like for a rigid body. If, however, the upper part spanned only a few floors (say, 3 to 6), then it could be so flexible that different column groups of the upper part could move down separately at different times, producing a series of small impacts that would not be fatal...
Bazant & Zhou state an arbitrary figure of "say, 3 to 6" floors as being the upper limit for the structure to be flexible enough to disintegrate and cause smaller impacts. However, since the cap is constructed in exactly the same manner as the structure below, as it destroyed each floor of the structure below, it would also be equally destroyed. Therefore, with the cap of WTC1 being comprised of 12 floors, it would be completely disintegrated into constituent parts after destroying 12 floors below it. This contention is supported by video and photographic records of the collapse. Many non-fatal, smaller impacts would lead to a decay in, and an eventual halt in the collapse.
References:
[1] The Collapse: An Engineer's Perspective http://www.pbs.org/wgbh/nova/wtc/collapse.html
[2] NIST and the World Trade Center http://wtc.nist.gov/
[3] Final Report of the National Construction Safety Team on the Collapses of the World Trade Center Towers (Draft) http://wtc.nist.gov/pubs/NISTNCSTAR1Draft.pdf
[4] Why Indeed Did the WTC Buildings Collapse? http://www.physics.byu.edu/research/energy/htm7.html
[5] 9-11 Research http://911research.wtc7.net/
[6] The Destruction of the World Trade Center: Why the Official Account Cannot Be True http://911review.com/articles/griffin/nyc1.html
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| shaolin_Z |
| quote: | Originally posted by pkcRAISTLIN
intellectually dishonest. |
Intellectual dishonesty is believing in a phenomenon that defies common sense and the laws of physics, or comes incredibly close to that. So please stop accusing me of it. I don't care what kind of explanation a selective group of "experts" offer if it isn't consistent with the laws of physics or comes very close to it. Plus, the scientific aspect is only one aspect to 9-11, you guys have failed to address everything else. And you've failed to address the scientific aspect in any meaningful way, or offer any believable alternative.
| quote: | Originally posted by pkcRAISTLIN
well, thats where you and i disagree. i was basically asking you to explain the correlation between the seismic data a little further. because i didnt believe it was that easily transferable, and whattya know!? it sounds as if i was right
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and after consulting one of his professors, colonel came up with this
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forgive me, but that sounds an awful like
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Did you miss my post preceding your's where I responded to colonelcrisp's? |
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| pkcRAISTLIN |
| quote: | Originally posted by shaolin_Z
Intellectual dishonesty is believing in a phenomenon that defies common sense and the laws of physics, or comes incredibly close to that. So please stop accusing me of it. |
no, its intellectually dishonest to compare two completely different structures when its been illustrated time and time again that they are different and incomparable.
| quote: | Originally posted by shaolin_Z
I don't care what kind of explanation a selective group of "experts" offer if it isn't consistent with the laws of physics or comes very close to it. Plus, the scientific aspect is only one aspect to 9-11, you guys have failed to address everything else. And you've failed to address the scientific aspect in any meaningful way, or offer any believable alternative. |
"selective"?? the world's engineers are a selective group of experts? wow, id like to know what constitutes a substantial body of experts by your way of thinking.
| quote: | Originally posted by shaolin_Z
Did you miss my post preceding your's where I responded to colonelcrisp's? |
no, but i am unqualified to debate that. ill leave that up to people like colonel.
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Rapid Collapses and Conservation of Momentum and Energy
Jones: “How do the upper floors fall so quickly, then, and still conserve momentum and energy in the collapsing buildings? The contradiction is ignored by FEMA, NIST and 9-11 Commission reports where conservation of energy and momentum and the fall-times were not analyzed. The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses (Harris, 2000).”
To many people the apparent collapse of the buildings at ‘near free-fall-speed’ is one of the most compelling arguments in favour of the CD theory. However it is also the most easily dealt with on scientific grounds. The fact is that the near free-fall-speed of collapse of buildings in controlled demolition is entirely due to gravity, and not to explosives. The question of course remains, how come that buildings, impeded by their intact lower floors, collapse so fast? (Though of course, this is not a question with any direct relevance to 9/11.) Put this way, the question conveys the essential fact of controlled demolition: that the only floors effectively ‘removed’ from the building are the lowest. (Further charges are placed in the building if and only if it is necessary to guide its fall in a certain way, for example to collapse a building into its footprint.) In a 20-story building, for example, the bottom floor or floors is extensively rigged with explosive, to remove its load-bearing capability. The remaining 18-odd storeys pancake into the region of the destroyed floor, one at a time, raising exactly the same question as to how is it that this process can take place so quickly? The same question applies to conventional demolition, and to the Tower buildings. The difference is that the pancaking occurs high in the Twin Towers (‘top-down pancaking’), and at the base of WTC 7 (‘bottom-up pancaking’). In the usual bottom-up process each floor impedes the process of collapse through its structural rigidity, just as much as one would expect in the top-down processes in the Towers. Although no text-book account is available which might give a simple answer to the issue of the speed of gravitational collapse of buildings, one might draw on the analogy of a hydraulic press compressing, say, a car body shell. The car body shell may seem strong enough to withstand everyday loadings, but, when it takes the hit of a high-powered press, it collapses with astonishing speed. 18 storeys of a big building, moving even rather sedately as they would at the onset of collapse, probably outstrip the forces of even the biggest hydraulic press ever built.
It seems that all the proponents of the CD theory state the case, like Jones above, along the lines: “The paradox is easily resolved by the explosive demolition hypothesis, whereby explosives quickly remove lower-floor material including steel support columns and allow near free-fall-speed collapses.” This is simply unscientific; not corresponding to the reality of how controlled demolition is carried out. Returning to our example of the collapse of a 20-story building, there is simply no need to explode each floor, and such explosions are certainly not the explanation of why buildings fall so fast in controlled demolition. All the calculations produced by the CD theorists, designed to prove their theory, are based on the wrong premise, that explosions accelerate the descent. They don’t: it is purely gravity that does it.
Jones: “We observe that approximately 30 upper floors begin to rotate as a block, to the south and east. They begin to topple over, not fall straight down. The torque due to gravity on this block is enormous, as is its angular momentum. But then – and this I’m still puzzling over – this block turned mostly to powder in mid-air! How can we understand this strange behavior, without explosives?”
Jones seems to believe that a 30-story section of the building was “turned mostly to powder in mid-air,” through the use of explosives. He ignores the fact that large sections of the building, such as this, did fall, and were responsible for destroying or partly destroying other WTC buildings. Although considerable disintegration of the 30-story block was inevitable as it impacted on the rest of the South Tower, the bulk of the pulverisation would have been on impact on the WTC complex. Here is a photo of a large chunk of WTC 2 falling onto WTC 3, which was almost totally destroyed by debris falling from the Towers. This fragment shows a different orientation to the section described by Jones, which suggests that angular momentum was conserved. |
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In every photo and every video, you can see columns far outpacing the collapse of the building. Not only are the columns falling faster than the building but they are also falling faster than the debris cloud which is ALSO falling faster than the building. This proves the buildings fell well below free fall speed. That is, unless the beams had a rocket pointed to the ground.
Just look at any video you like and watch the perimeter columns.
Deceptive videos stop the timer of the fall at 10:09 when only the perimeter column hits the ground and not the building itself. If you notice, the building just finishes disappearing behind the debris cloud which is still about 40 stories high.
Below is a more accurate graphic using a paper written by Dr. Frank Greening which can be found at: http://www.911myths.com/WTCREPORT.pdf
The paper takes the transfer of momentum into account. Like a billiard ball being hit by another on a pool table, each floor transferred its momentum to the next as represented below. The more weight, the less resistance each floor gave. |
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The time required to strip off a floor, according to Frank Greening, is a maximum of about 110 milliseconds = 0.110 seconds. It is rather the conservation of momentum that slowed the collapse together with a small additional time for the destruction of each floor.
Below are calculations from a physics blogger...
When I did the calculations, what I got for a thousand feet was about nine seconds- let's see,
d = 1/2at^2
so
t = (2d/a)^1/2
a is 9.8m/s^2 (acceleration of gravity at Earth's surface, according to Wikipedia), [He gives this reference so you can double check him.]
d is 417m (height of the World Trade Center towers, same source)
so
t = (834m/9.8m/s^2)^1/2 = 9.23s
OK, so how fast was it going? Easy enough,
v = at
v = (9.8m/s^2 x 9.23s) = 90.4m/s
So in the following second, it would have fallen about another hundred meters. That's almost a quarter of the height it already fell. And we haven't even made it to eleven seconds yet; it could have fallen more than twice its height in that additional four seconds. If the top fell freely, in 13.23 seconds it would have fallen about two and one-half times as far as it actually did fall in that time. So the collapse was at much less than free-fall rates.
Let's see:
KE = 1/2mv^2
The mass of the towers was about 450 million kg, according to this. Four sources, he has. I think that's pretty definitive. So now we can take the KE of the top floor, and divide by two- that will be the average of the top and bottom floors. Then we'll compare that to the KE of a floor in the middle, and if they're comparable, then we're good to go- take the KE of the top floor and divide by two and multiply by 110 stories. We'll also assume that the mass is evenly divided among the floors, and that they were loaded to perhaps half of their load rating of 100lbs/sqft. That would be
208ft x 208ft = 43,264sqft
50lbs/sqft * 43264sqft = 2,163,200lbs = 981,211kg
additional weight per floor. So the top floor would be
450,000,000 kg / 110 floors = 4,090,909 kg/floor
so the total mass would be
4,090,909 kg + 981,211 kg = 5,072,120 kg/floor
Now, the velocity at impact we figured above was
90.4m/s
so our
KE = (5,072,120kg x (90.4m/s)^2)/2 = 20,725,088,521J
So, divide by 2 and we get
10,362,544,260J
OK, now let's try a floor halfway up:
t = (2d/a)^1/2 = (417/9.8)^1/2 = 6.52s
v = at = 9.8*6.52 = 63.93m/s
KE = (mv^2)/2 = (5,072,120kg x (63.93m/s)^2)/2 = 10,363,863,011J
Hey, look at that! They're almost equal! That means we can just multiply that 10 billion Joules of energy by 110 floors and get the total, to a very good approximation. Let's see now, that's
110 floors * 10,362,544,260J (see, I'm being conservative, took the lower value)
= 1,139,879,868,600J
OK, now how much is 1.1 trillion joules in tons of TNT-equivalent? Let's see, now, a ton of TNT is 4,184,000,000J. So how many tons of TNT is 1,139,879,868,600J?
1,139,879,868,600J / 4,184,000,000J/t = 272t
Now, that's 272 tons of TNT, more or less; five hundred forty one-thousand-pound blockbuster bombs, more or less. That's over a quarter kiloton. We're talking about as much energy as a small nuclear weapon- and we've only calculated the kinetic energy of the falling building. We haven't added in the burning fuel, or the burning paper and cloth and wood and plastic, or the kinetic energy of impact of the plane (which, by the way, would have substantially turned to heat, and been put into the tower by the plane debris, that's another small nuclear weapon-equivalent) and we've got enough heat to melt the entire whole thing.
Remember, we haven't added the energy of four floors of burning wood, plastic, cloth and paper, at- let's be conservative, say half the weight is stuff like that and half is metal, so 25lbs/sqft? And then how about as much energy as the total collapse again, from the plane impact? And what about the energy from the burning fuel? You know, I'm betting we have a kiloton to play with here. I bet we have a twentieth of the energy that turned the entire city of Nagasaki into a flat burning plain with a hundred-foot hole surrounded by a mile of firestorm to work with. - Schneibster edited by Debunking 911
Let me make this clear, I don't assume to know what the ACTUAL fall time was. Anyone telling you they know is lying. The above calculation doesn't say that's the fall time. That was not its purpose. It's only a quick calculation which serves its purpose. To show that the buildings could have fallen within the time it did. It's absurd to suggest one can make simple calculations and know the exact fall time. You need a super computer with weeks of calculation to take into account the office debris, plumbing, ceiling tile etc.. etc... Was it 14 or was it 16? It doesn't matter to the point I'm making, which is the fall times are well within the possibility for normal collapse. Also, the collapse wasn't at free fall as conspiracy theorists suggest.
For more analysis of the building fall times, go to 911myths free fall page.
Please refer to Dr Frank Greening's paper for detailed calculations.
http://www.911myths.com/WTCREPORT.pdf |
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