Physics Of 9/11 Events

wcelliott

11th July 2007 - 09:11 AM

QUOTE

I just found the most ideal way to measure the acceleration of the early collapse.

If there was a video, even normal-resolution, with some way to reference the time to it, and some way to extract individual .jpg or bitmaps from it, you could do it with PowerPoint. Just draw a best-fit line on the image and do a right-click on the line, and the line's properties will tell you the angle it makes.

Take that angle and drop it into Excel along with its time.

When you have a suitable dataset, you can plot the angle versus time or calculate an angle-rate as a function of time in Excel and plot it log-linear so you don't lose the small angle rates from the early data.

I'm not assuming it'd be logarithmic in nature, but I think it's premature to rule out log characteristics, just because the loads aren't logarithmic, doesn't mean the structure won't respond in a logarithmic way. We are talking about steel stretching and deforming in a plastic way, and I don't know what those curves look like, but in any case, the angle-rates will start out small and if we want to see them on the same plot as the angle-rates at the collapse, we'll need a log-scale to see them both.

Where discontinuities seem to exist, we could go back into the video and collect more samples to see exactly where they occurred.

I don't have any videos, and I'm not sure how to frame-grab a still from a video anyway, but sub-pixel resolution should be relatively easy to get. A line that's one pixel higher on one end of the line than the other should look something like:

___________________________-----------------------------------------

or with noise:

________-_________-_-----____-_-----

--__--------------

---------

At a later point we could do the trig to invert the projection geometry, and get angles relative to absolute vertical/horizontal, especially if there's information available on where the camera was located.

metamars

11th July 2007 - 09:17 AM

QUOTE (NEU-FONZE+Jul 11 2007, 12:26 AM)

Thanks David!

That's exactly what I was thinking...........

Is it too hard for you to tell me explicitly whether you have done this already, or not?

einsteen

11th July 2007 - 09:35 AM

There are a lot of methods of course. btw I was not refering to the tilt as function of time that will be much more complex.

Skeptik

11th July 2007 - 11:22 AM

QUOTE (wcelliott+Jul 11 2007, 07:11 AM)

Yes.

There were structural failures on the impact-damaged floors as the fires progressed. When a structural member fails, it sends a shock wave through the remaining steel structure. This propagates at the speed of sound in steel, about 20,000feet/second, as a shock wave. Whereever that structure's bulk acoustic impedance changed, like at floors that were more solidly built (i.e., mechanical floors and basement), the shock wave would be reflected by the discontinuity. That reflection doubles the intensity of the shock wave. It's like "Crack-the-Whip", the kid in the middle doesn't feel anything, the kid on the end always wipes out.

This happens in high-energy laser mirrors, too, it's the limiting factor that determines how much energy that a laser mirror can take before it's damaged.

And just how reasonable is the explanation that involves explosives, anyway? Where are those explosions? When do they go off? And how does that fit either the conspiracy theory or the observed collapse starting at the impact-damaged floor?

Did this structural shock wave cause the wrecked cars? If so, how?

On another point, if the pancaking of the floors caused the destruction so quickly, how come the central core was destroyed? What pancaked onto them? What caused the central columns to collapse at the same time as the pancaking floors?

Daru

11th July 2007 - 12:22 PM

QUOTE (lozenge124+Jul 11 2007, 02:41 AM)

Full text here:
http://911truth.org/article.php?story=20070706155755469

Very wisely written.

wcelliott

11th July 2007 - 02:22 PM

QUOTE

The cars, along with a lot of other fire-related destruction in the basement, probably happened when the aircraft's fuel ignited and the fireball shot down the central core. The central core was a hollow tube, like a chimney, right down the middle of the tower.

The floors didn't drop instantly, the brackets holding them to the perimeter walls were weakest and probably went first, not simultaneously, but piecemeal, then unzipping once there were too many failures too close together along a perimeter wall.

The brackets holding the floors to the core columns were more substantial, so they probably failed next, in a similar manner as described above, but as the perimeter brackets failed, that left only the core columns to bear the entire weight of the floor, which they weren't designed to do. As the brackets failed, piecemeal, that placed side-loads on the core columns which weren't designed to bear the over-load + side-loads, they were designed to bear the top-load with the floors keeping them perfectly vertical. Without the side support, and with perturbations from the floors pulling them from vertical, the top-load squished and buckled the core columns.

This isn't a clear sequence in the sense that all things of one category happened before anything of the next, as all things of all categories were happening all at once. But for the idealized case, the floor fails first at the perimeter wall, then at the core, then the floor collapses to the floor below leaving the perimeter wall and core columns unsupported, and the perimeter wall tips outwards before the brackets holding the trees together fail, and the core columns twist and collapse under the combined load of the undetached parts of the floors as they're failing plus the weight of the falling part of the tower, above.

When floors pancake/fail, they send shock-waves down the remaining steel structure at 20,000feet/second, about 20x the speed of sound in air, so people at street level feel the shock-waves and hear them coming from the ground level before they hear them through the direct air-path from 800 feet above. Floors pancaking sound like "BANG-BANG-BANG", which is the upper "block" slamming into the floors one after the other. Eventually, the increasing tilt makes the floor collisions overlap in time and all you get is thunderous rumbling that sounds like a freight train.

And even though it sounded like a freight train, and people there said it sounded like a freight train, it wasn't a freight train. That concept seems difficult for a lot of people to grasp, so I'll repeat it. A lot of people said it sounded like a freight train, but a collapsing building made that sound, not a freight train. I'm surprised that there isn't a website dedicated to the theory that there was a secret freight train that hit the towers, because there are sites that say that there must've been random explosions because people heard "BANG"s. You can kick a steel garbage can and it'll sound like a grenade went off. That doesn't mean the garbage can had C-4 in it.

We've already addressed these topics before, skeptik, so maybe you'd like to page back a few pages and read what we've already written rather than make us start from scratch for your benefit.

We've got 350 pages of this stuff, you CDiots' groundless accusations answered by logic and engineering, and if there was a smoking gun, it'd have been found by now.

Your side is batting zero here. You're better off trolling where the IQs are lower.

Capracus

11th July 2007 - 02:41 PM

QUOTE (Daru+Jul 11 2007, 12:22 PM)

Very wisely written.

Very well written indeed. I applaud Kevin Ryan's detailed critique of the Purdue analysis. Kevin keenly zeros in on the critical flaw in the paper of Irfanoglu and Hoffman, they misidentified AA Flight 11 as Flight 77 and 71 respectively.

Another glaring mistake that Kevin failed to mention was that there are no fan blades visible in the engines of the 767 model used in their paper, how could such an essential detail be missed? I'm tempted to write the president of Purdue and add my voice of outrage.

einsteen

11th July 2007 - 02:56 PM

I tried to estimate te acceleration of wtc1, I think I've made an error somewhere because I got exactly 0.5g. I'm not really fresh today but wouldn't it even be lower when it doesn't topple ?

NEU-FONZE

11th July 2007 - 03:25 PM

Metamars:

I have indicated that I have done the type of graphing of the collapse of WTC 1 & 2 you are interested in. Some of the results have been included in reports on the web. Others, I am afraid, are in Excel spreadsheets and plots I have on my computer. These include comparisons of the rate of drop of the facade vs. the antenna of WTC 1. I continue to work on this issue and hope to put more of my results on the web one of these days....

memeticverb

11th July 2007 - 05:04 PM

Notice in this thread that we are witnessing a new level of anti-science aimed only at slowing down the understanding of this event.

This is a litmus test for the entire field of engineering and physics, not to mention architectural engineering, in that if one still believes that buildings with the structural integrity of those 3 WTC buildings fell with almost NO piling-up as expected with a pancake collapse, (as well as many other anomalies) one must have next to zero intuition in matters of engineering and physical science.

Below is a simple calculation published in the peer-reviewed Journal of 911 Studies:

The Sustainability of the Controlled Demolition Hypothesis
for the destruction of the Twin Towers
Tony Szamboti: Machanical Engineer
"The vertical load capacity of the beams, at their base, due to compressive loads only, was

Central core 300,000 tons x 1.67 = 500,000 tons
Perimeter 200,000 tons x 5.00 = 1,000,000 tons

Using the base as a reference, the actual load vs. the beam capacity, during a low wind day like Sept. 11, 2001, would have been

Actual Load/Beam Capacity = 500,000/1,500,000 = 33%

If 80% of the base central core columns had their strength unaffected by damage and/or fire they would have provided a remaining factor of safety and load capacity of 0.80 x 1.67 = 1.34 for a 300,000 ton load = 402,000 ton remaining capacity

If 80% of the base perimeter columns had their strength unaffected by damage and/or fire they would have provided a remaining factor of safety and load capacity of 0.80 x 5.00 = 4.00 for a 200,000 ton load = 800,000 ton remaining capacity

The remaining unaffected 80% of the tower structure would still have been capable of supporting 1,202,000 tons or 2.4 times the actual 500,000 ton load."

This indicates, as apparently needs to be constantly repeated to the anti-science agents, that the load capacity of the support columns, being HIGHLY redundant, would not have behaved the way it did, and likely would not have failed at all, even with 10 columns being completely severed, (which is a scenario as lozenge124 pointed out, that was even more extreme than what NIST calculated as possible).

metamars

11th July 2007 - 05:08 PM

QUOTE (NEU-FONZE+Jul 11 2007, 03:25 PM)

Well, I guess that's too bad for us. As this should be relatively easy to do with the right software (I mean the gross measurements, uncorrected for angularity), maybe someone else will oblige us in the near future.

One would think that one of the plentitudinous "debunkers" at JREF would have been happy to contradict Ross with more than just their assertions that his claim re the antenna dropping first is wrong, but apparently they're too busy showing everybody how smart they are.

metamars

11th July 2007 - 05:14 PM

From one of the less condescending posters at JREF:

http://forums.randi.org/showthread.php?t=73494

QUOTE

I'm not a structural engineer, but I worked for about 5 years as a structural draftsman, and this is the way I understand it: In structural engineering, "safety factor" and "factor of safety" mean two slightly different things. A "safety factor" is a multiplier applied to loads (or stresses, such as vertical force, torque, or bending moment) for each individual type of load (e.g. dead load, live load, wind load), an amount which depends on the type of component (columns, floors, stairs) and type of structure (residential, industrial, office). This factor is to account for possible underestimates in the loading (i.e. it's an "uncertainty factor"). Then, the total calculated load is multiplied by a "factor of safety" to account for possible flaws in materials or construction and degradation over time. Dead load safety factors are typically smaller than live (dynamic) loads, both because dead loads can usually be determined more accurately, and because there is a "size effect" associated with using too large a factor (because increasing the size of a component also increases its weight). Typical safety factors for commercial construction are 1.4 for dead load and 1.7 to 2 for most live loads. The factor of safety added at the end of the load calculation for steel structures is typically 1.67 (and that was the design criterion used in the WTC towers), and about 2 to as much as 5 for reinforced concrete (depending mainly on the type of component).

NIST "reverse-engineered" the columns in the WTC towers and found a "utilization factor" (the inverse of the factor of safety) of about 0.6 for the core columns and probably around 0.2 for the perimeter columns with respect to gravity loads alone (because the governing factor in the perimeter column design was wind loading, which wasn't a factor on 9/11).

But the thing that bugs me about "truther" use of these numbers is that if you lose structural integrity -- which surely happened in the collapse -- these numbers don't mean much at all. FEMA found that most of the perimeter columns and about half the core columns were not buckled at all, which implies that they were simply knocked out of the way before they reached their maximum capacity.

NEU-FONZE

11th July 2007 - 05:19 PM

Metamars:

I take the question of the pre-motion of the WTC 1 antenna very seriously. It is NOT a simple problem to analyze using the computer/software I have available, but nevertheless I am working on it. Even NIST changed its opinion on this question between the Draft and Final Reports. I would rather do it right than do it in a hurry just to post something on a forum!

Memeticverb:

The analysis you posted applies to a STATIC system. The actual collapse of the towers is highly dependent on DYNAMIC forces.... ask Metamars... this is one of his favorite topics!

Grumpy

11th July 2007 - 05:29 PM

lozenge124

QUOTE

In one important way this new animation does reflect reality, although in doing so it negates the official stance taken by the National Institute of Standards and Technology (NIST). In their September 2005 report, NIST presented their "collapse initiation sequence", and explained how they felt the loss of fireproofing was the key to the destruction of the towers. NIST suggested that the fireproofing loss occurred as a result of aircraft debris, in the form of shotgun-like blasts, scraping the fireproofing off of thousands of square meters of surface area.[2] But from Purdue's new animation, we can clearly see that the aircraft that impacted the WTC tower could not have been instantly transformed into thousands of tiny pellets in the form of shotgun blasts. The animation more realistically displays the large fragments of debris from the fuselage clattering around in the skeletal framework of the tower. For this reason we must thank Purdue for this visualization that negates NIST's primary explanation.

That might be true IF you ignore the several tons of fan blades in the engines that would instantly convert into a high speed/energy cloud of very hard metalic debris broken into tiny pieces more akin to a multi ton hand grenade than to a shotgun blast. This cloud of hard metal pieces could easily strip large areas of fireproofing.

Also to be concidered would be the hydralic blasting effects of the hundreds of tons of fuel. Anyone who has used a pressure washer can easily understand the PAINT STRIPPING effects of such high velocity streams of liquid. If water will strip paint at those velocities a few hundred tons of fuel should have no problem stripping large areas of foamlike fireproofing.

Kevin Ryan should(and probably does) understand these effects, but he fails to mention them because it would negate the point he is trying(unsuccessfully) to make, therefore his honesty, integrity and believability are trashed(much like G.Ross, Prof Jones, etc.).

NIST's explanations are entirely unaffected by the pseudo-scientific bleatings of politically(and financially) motivated charlatans such as Ryan, Ross and Jones, et al. The only valid critique of the Purdue simulation that I see is that it was of a much less detailed type than NIST's, leaving important details(such as the engines exploding and the fuel stripping) out. Nit pick all you like, but this is really a pathetic attempt by those of questionable character with their own agendas(Want to buy a T-shirt??? How about a video??? All together now,"Baaa")

Grumpy

Grumpy

11th July 2007 - 05:50 PM

memeticverb

QUOTE

"The vertical load capacity of the beams, at their base, , was

Central core 300,000 tons x 1.67 = 500,000 tons
Perimeter 200,000 tons x 5.00 = 1,000,000 tons

Using the base as a reference, the actual load vs. the beam capacity, during a low wind day like Sept. 11, 2001, would have been

Actual Load/Beam Capacity = 500,000/1,500,000 = 33%

If 80% of the base central core columns had their strength unaffected by damage and/or fire they would have provided a remaining factor of safety and load capacity of 0.80 x 1.67 = 1.34 for a 300,000 ton load = 402,000 ton remaining capacity

If 80% of the base perimeter columns had their strength unaffected by damage and/or fire they would have provided a remaining factor of safety and load capacity of 0.80 x 5.00 = 4.00 for a 200,000 ton load = 800,000 ton remaining capacity

The remaining unaffected 80% of the tower structure would still have been capable of supporting 1,202,000 tons or 2.4 times the actual 500,000 ton load."

This indicates, as apparently needs to be constantly repeated to the anti-science agents, that the load capacity of the support columns, being HIGHLY redundant, would not have behaved the way it did, and likely would not have failed at all, even with 10 columns being completely severed, (which is a scenario as lozenge124 pointed out, that was even more extreme than what NIST calculated as possible).

1) "compressive loads only" in no way represents having the top of the building fall on the lower section.

2) Your calculations ignore the effects of temperature on steel. A temp of 600C(easily reached in any fire) the steel loses ~80% of it's strength.

3) the frame strength is irrelivant if there is no way for it to be applied. The relativly narrow vertical beams could not hold up the growing pile of rubble, that force fell onto the floors for the most part. The floor connections failed before a significant resistive force could be generated, totally bypassing the core and frames, pushing the outer frames aside intact(not buckled) and greatly overloading the core beams, especially unbraced by the floors.

Please stop parroting stuff you do not(or can not) understand and start thinking for yourself.

Grumpy

David B. Benson

11th July 2007 - 08:27 PM

QUOTE (memeticverb+Jul 11 2007, 05:43 AM)

Is there a reasonable explanation for the severe damage occurring in the basements prior to collapse ... ?

Yes, fireballs racing down the voids in the core, shortly after aircraft impact. (This is known to have occurred).

wcelliot has suggested mechanical waves, but none of the tower occupants appear to have noticed more than the sway induced by the impacts.

David B. Benson

11th July 2007 - 08:34 PM

QUOTE (Skeptik+Jul 11 2007, 11:22 AM)

On another point, if the pancaking of the floors caused the destruction so quickly, how come the central core was destroyed? What pancaked onto them? What caused the central columns to collapse at the same time as the pancaking floors?

WTC 1:

(1) Three walls buckle and the top portion tilts to the south.

(2) The load of these three walls was transfered to the core by the hat truss.

(3) Vastly overloaded, core column members buckle and the connections fail.

David B. Benson

11th July 2007 - 08:49 PM

QUOTE (memeticverb+Jul 11 2007, 05:04 PM)

Notice in this thread that we are witnessing a new level of anti-science aimed only at slowing down the understanding of this event.

Tony Szamboti: Machanical[sic] Engineer

(1) Yes. You are providing it.

(2) You would think that mechanical engineers would at least know what is in a textbook such as

G.J. Simitses & D.H. Hodges
Fundamentals of Structural Stability
Elsevier, 2006.

You would think they could manage to obtain correct masses for the towers and correctly determine the average capacity of the columns. But no, it seems not. Not Tony nor Gordon. Jeez.

Correctly, via SAP 2000, as reported by NIST:
Before impact the average DCR of core columns was 0.5 and the average DCR of exterior wall columns was 0.2.

Now maybe mechanical engineers do not study DCRs, but structural engineers are required to use DCR calculations to determine if their designs are safe and efficient. It isn't hard to use web searching to learn about DCRs. It's even easier to discover the requirement and equations used to calculate DCRs.

I suggest you might care to do so, alleviating point (1)...

einsteen

11th July 2007 - 09:39 PM

It seems that nobody is interested in my method. Drop a movie on virtualdub (=freeware), then use the Nul Transform filter, press cropping and select an 1xn area of the movie, save image sequence... and you have m times a different 1xn bitmap. Then combine it to a m x n bitmap. Horizontally tou then have the time, 29.97 pixels for example is a second for NTSC and vertically you have the distance which is a matter of counting pixels and estimate it. I will try to estimate it later seriously and am also attempting to set up a paper, which I would like to peer-review at this forum... but I'm now going to play some piano and youtube it, of course with an other nickname...

David B. Benson

11th July 2007 - 09:47 PM

QUOTE (einsteen+Jul 11 2007, 09:39 PM)

It seems that nobody is interested in my method.

On the contrary! I am always interested in obtaining good drop data, especially for WTC 1.

Indeed for WTC 1, the corrections for the tilt are too insignificant to matter. So don't let that concern you. What should is the perspective of the video and the necessary corrections for that.

I would very much like to have more (and maybe even better) data for WTC 1 than that provided by NEU-FONZE. I'll bet he is interested as well...

David B. Benson

12th July 2007 - 12:09 AM

Well, well. Imagine that.

Now from top to the very bottom, WTC 1 core columns were 438.3 meters tall. Assuming that at the elastic limit mild steel's compression ratio is 0.002, that means the top can sink 0.877 meters before inelastic behavior begins.

However, the self-load, under normal, mild breeze, conditions consume about 0.3 meters of that.

But with the antenna tower tilted a mere one degree of arc, hinged on the north wall, the core columns are compressed another 0.5--0.6 meters. That is right at the elastic limit.

So maybe the core did fail first. If so, the hat truss immediately transfers loads onto the bowing-in exterior walls and those buckle.

Either way, it only takes about 0.4 seconds, or less, for all this to start. Looking forward to einsteen's data.

RealityCheck

12th July 2007 - 12:49 AM

QUOTE (David B. Benson+Jul 12 2007, 12:09 AM)

Hi DBB!

If the perimeter columns deformed and 'shed' their load onto the 'core' structure, naturally the core would fail (especially with all that 'shifting' and heating/cooling as well).

But it still means the PERIMETER columns had to FIRST 'fail' to carry their load to SOME SIGNIFICANT DEGREE in order that the 'core' be overloaded/overstressed enough to fail, no?

So the perimeter did 'fail', first....followed by 'inveitable failure' of the core, according to your most recent figures.

That's how I read the whole thing!

Or are you saying that the antenna/roof-line could have 'tilted' WITHOUT FIRST having the degree of 'failure' of perimeter columns as described?

Cheers all!

RTC.
.

lozenge124

12th July 2007 - 12:57 AM

QUOTE (einsteen+Jul 11 2007, 08:26 AM)

Very nice picture. It's an interesting method - you certainly get a nice scientific looking curve out of it. Good job!

David B. Benson

12th July 2007 - 01:01 AM

QUOTE (RealityCheck+Jul 12 2007, 12:49 AM)

Or are you saying that the antenna/roof-line could have 'tilted' WITHOUT FIRST having the degree of 'failure' of perimeter columns as described?

I'm suggesting that it is possible that the core failed 'first'. Many of the surviving core columns had members with considerable strain, two over 7%. The remaining competent core column members had DCRs in the range 0.94--1.08. That's at 100 minutes.

The bowing-in of the south wall would tend to cause the antenna tower and hence the core to tilt that way. So the suggestion is that just this change was enough to trigger core collapse, which then caused the walls to buckle.

However, since whichever was 'first', the other followed in less than half a second, perhaps only 0.2 seconds later.

In any case, I am just offering this as a possibility, and don't see (at least just now) any easy way to tell the two possibilities apart...

RealityCheck

12th July 2007 - 01:59 AM

QUOTE (David B. Benson+Jul 12 2007, 01:01 AM)

Hi DBB!

Understood.

Thanks for the clarification, mate!

PS: For that tower whose top first leaned one way and then later leaned the other way, it would indicate to me that the 'core' was still 'just holding' in order for that total lean-reversal 'pivoting' to take place ON the core. That's why I think that, even if the core was 'terminal', it was not actually 'gone' until the 'pivoting' occurred, which would indicate that the OPPOSING perimeter walls were 'failing in turn' one way and then the other while the core (weakened as it was) did not fail until the 'tipping' CAUSED by the one side and then the other side perimetr columns failure, took the 'core' over the edge of that 7%. See what I was getting at?

RC.
.

roves shill

12th July 2007 - 02:27 AM

QUOTE (wcelliott+Jul 11 2007, 03:05 AM)

It sounds like you're focussing on trivia and missing the big picture.

Big plane hits building, building gets damaged from impact, fire weakens what's left of structure, building collapses.

Times two.

Then, what happened was that the terrorists who planned it in the first place realized that they bit off more than they could chew, and started lying their [removed]'s off trying to duck the responsibility for their own actions, hoping to stop the war that they're losing.

And lots of imbeciles believed the lies.

And here we are.

Wow, great stuff!!! here we are again, and still pushing the fuel down the elevator shaft theory!! An oldie but a goodie!!! Lack of imagination, but very theatrical. Nice. But once again, I would implore you to put your money where your mouth is. You know where all those retired jumbos are out on the Mojave. By all means, take advantage of this newly found demolition technique and exploit it. Start your own demolition service "recycling" these retired planes. According to the theory you are putting forth here on this thread, there is no down side. Three global collapses out of two attempts with minimal collateral damage to non-WTC buildings surrounding perimeter of complex, all seven WTC buildings removed within six months of 9/11, opening up some of the most expensive real estate on the planet. You woundn't have any preparation, wiring, hardly any man hours. Your costs would be minimal. Hell, you could even offer same day service in the US and Canada. If you truly believe what you are putting forth here, you are going to be a rich man. Put up or shut up.

RS

newton

12th July 2007 - 03:40 AM

QUOTE (Grumpy+Jul 10 2007, 12:27 PM)

newton

The real reason for the existence of a troother site...

http://www.911truthstore.com/911truth/catalog/

VISA and MASTERCARD accepted...

Can you say "Baaa"??? I thought you could.

Grumpy

QUOTE

Halliburton's total assets were $15 billion at the end of 2005

i wonder how many t-shirts haliburton had to sell for that bottom line?

why is grumpy's OFF TOPIC post allowed to stand, i wonder aloud?

wcelliott

12th July 2007 - 03:43 AM

QUOTE

all seven WTC buildings removed within six months of 9/11, opening up some of the most expensive real estate on the planet.

And you act like they had a financial motive for destroying the WTC towers.

They were plenty profitable while standing, and since then six years) they've earned ZERO RENT.

And it isn't clear that they're going to start building the replacements anytime soon.

And one of the reasons that they're dragging their feet building the replacements is that the general concern is that they may as well paint bulls-eyes on the new towers, as they'd represent a tempting target for a future terrorist attack, their way of saying that they can destroy anything we build. And then the point becomes how much extra security will new renters be willing to put up with, and also, how much are they going to be willing to pay for? The very same security guards who're going to be frisking you every time you enter the building actually CHARGE you for being pains in your butt. They've redesigned the bottom six floors of the building (IIRC), making them car-bomb resistant, meaning no window offices below the seventh floor, so the interior space will be like a cave.

How would YOU like to rent space there?

That's at least part of the reluctance of starting the construction there, they're hoping to achieve some sort of clear victory over the terrorists before they finish the building, otherwise nobody's going to want to move into the place and the money invested in building it will be lost.

The 9/11 attacks were disastrous financially for the owners/investors of the WTC, and the financial hemorrhaging hasn't stopped and isn't going to stop anywhere in the near future.

Fundamental to a covert operation is that you don't want witnesses. This was downtown Manhattan, with live TV news helicopters and thousands of people with camcorders in broad daylight. Not to mention the fact that the towers were occupied, it being business hours. And you CDiots assert that there were bombs going off at random times and random locations all during the evacuation. Some covert operation. Don't you suppose that people who do covert operations planning for a living might have come up with something less risky? At a minimum, they could've changed the *time* of the attacks to, say, 3am Sunday morning when it's dark out and most people are asleep. Or attack a more symbolic target like the Statue of Liberty, which would be a sufficient excuse for us to go to war while minimizing the impact on the US economy, and access to the island being strictly controlled, it would've been duck soup to plant explosives without any risk of getting caught. Or a poison-gas attack on the subways - no property damage, no economic damage, and with prompt emergency medical care, they could've demonstrated how great FEMA works, gaining our trust.

Nope. WTC towers attacked, billions in direct damages, tens of billions in indirect damages, 3,000 lives lost. And you figure it was an inside job, and motivated to free-up expensive real estate.

As for how easy it was to demolish the buildings, they were an optimized design, meaning they were a marginal design. Necessarily. They couldn't afford to make it much stronger than they made it without making it much more expensive to build (and rent). More steel in upper floors would've meant much more steel in middle-level floors to support the extra load above, meaning so much steel at the bottom floors that there wouldn't be any floor space left to rent.

Learn something and get back to us.

wcelliott

12th July 2007 - 03:55 AM

QUOTE

why is grumpy's OFF TOPIC post allowed to stand, i wonder aloud?

What technical insight have you EVER brought to this forum?

EVER?!?

You steadfastly refuse to grasp even the most obvious concepts that don't support your anti-American political agenda, acting smugly superior in the process.

YOU don't belong here. YOUR posts provide ZERO insight.

newton

12th July 2007 - 04:26 AM

QUOTE (wcelliott+Jul 12 2007, 03:55 AM)

are you kidding?
i don't think you've read all two thousand pages of the previous two threads.

it's just that i don't like to limit myself to just the physics of 9/11, and OCTs get pissed about that. even the website owners are OCTs, and only tolerate me and the other CTers, because it would be an admission of guilt to simply ban us.

heard of the global village? it's real. the world is a small town, now. everyone knows everyone.

the gravitational potential of mass A, cannot crush mass 5(A). pretty simple. never mind in a factor of t1.3 over freefall.
a 47 seven storey building falls in 6.6 seconds over freefall, with limited structural damage to account for it. gravity cannot do that. gravity and fire together cannot do it.
the NIST report on tower seven says, ......????????
the inside of the building cannot be destroyed faster than something freefalling on the outside, and yet, this is observable on video... 'demolition waves' outpacing freefalling debris.

your posts are insulting the intelligence of a large group of scholars and experts.

'anti-american' is an archaic term. there is no more america. it's spelled with a k, now...amerika.

the secret service is reading my emails. it's not paranoia, it's a published fact. no warrants are needed, habeus corpus can be suspended on a rumour, and an individual's sovereign rights are a thing of the past.

i'm canadian, by the way, so i'm actually pro-american, as in, the MYTHICAL america of dreams, before surveillance became the number one agenda of the government, and damn straight i'm against the 'new american century' military/pharmaceutical/industrial cabal of malthusian oligarchs.

go support a private bank or something. you bother me.

adoucette

12th July 2007 - 04:33 AM

QUOTE (newton+Jul 11 2007, 11:26 PM)

are you kidding?
i don't think you've read all two thousand pages of the previous two threads.

I have read them all and all you do is hand wave.

Its all you have ever done.

As in this post.

Its all you will ever do.

As to your "scholars and experts", let us know when one publishes something in an actual peer reviewed scientific journal.

Arthur

wcelliott

12th July 2007 - 05:10 AM

QUOTE

the inside of the building cannot be destroyed faster than something freefalling on the outside, and yet, this is observable on video... 'demolition waves' outpacing freefalling debris.

QUOTE (->

QUOTE

the inside of the building cannot be destroyed faster than something freefalling on the outside, and yet, this is observable on video... 'demolition waves' outpacing freefalling debris.

Gee, for such a smart guy who "groks physics" and associates with such educated people, you'd think that someone like you would've heard about the "speed of sound in steel".

Especially if you'd read any of my posts regarding the WTC towers.

Remember this?
There were structural failures on the impact-damaged floors as the fires progressed. When a structural member fails, it sends a shock wave through the remaining steel structure. This propagates at the speed of sound in steel, about 20,000feet/second, as a shock wave. Whereever that structure's bulk acoustic impedance changed, like at floors that were more solidly built (i.e., mechanical floors and basement), the shock wave would be reflected by the discontinuity. That reflection doubles the intensity of the shock wave. It's like "Crack-the-Whip", the kid in the middle doesn't feel anything, the kid on the end always wipes out.

This happens in high-energy laser mirrors, too, it's the limiting factor that determines how much energy that a laser mirror can take before it's damaged.

And just how reasonable is the explanation that involves explosives, anyway? Where are those explosions? When do they go off? And how does that fit either the conspiracy theory or the observed collapse starting at the impact-damaged floor?

Doesn't that sound like your "demolition wave"? It has nothing to do with explosives, it's just what a steel structure does when it starts failing.

newton

12th July 2007 - 05:27 AM

no. it doesn't sound like my demolition wave. it sounds like wcelliot's fantasy island.

for OCTs, the case is solved, and any loose ends are easily handwaved.

for CTers, the investigation has only begun.

"A lie can travel around the world
while the truth is just putting on its shoes."
Mark Twain

i am sorry if i ignore irrelevant tripe, because i can't be bothered to entertain another OCT goosechase.

memeticverb

12th July 2007 - 05:27 AM

QUOTE (NEU-FONZE+Jul 11 2007, 05:19 PM)

Memeticverb:

The analysis you posted applies to a STATIC system. The actual collapse of the towers is highly dependent on DYNAMIC forces.... ask Metamars... this is one of his favorite topics!

Right, those numbers are given as the base load for the towers and weren't intended to show what was happening when th towers collapsed. But how could one calculate the dynamic forces without a base to start with? Is it possible to calculate the load distribution of a structure whose columns, one by one, are failing in a particular area?

memeticverb

12th July 2007 - 05:45 AM

QUOTE (Grumpy+Jul 11 2007, 05:50 PM)

memeticverb

1) "compressive loads only" in no way represents having the top of the building fall on the lower section.

2) Your calculations ignore the effects of temperature on steel. A temp of 600C(easily reached in any fire) the steel loses ~80% of it's strength.

1) Im very interested in seeing a model that shows how "the top of the building" "fell" "on the lower section." Please post a link to this model so people can discuss the real facts of the WTC collapse.

2) This could be assumed for the sake of argument. But the plausibility of the core columns having lost even 50% of their weight capacity by the time the building shows signs of rapid global collapse is is greatly reduced by the state of the fires, which was almost certainly cooling, not getting hotter.

memeticverb

12th July 2007 - 06:04 AM

QUOTE (wcelliott+Jul 11 2007, 07:11 AM)

When a structural member fails, it sends a shock wave through the remaining steel structure. This propagates at the speed of sound in steel, about 20,000feet/second, as a shock wave. Whereever that structure's bulk acoustic impedance changed, like at floors that were more solidly built (i.e., mechanical floors and basement), the shock wave would be reflected by the discontinuity. That reflection doubles the intensity of the shock wave. It's like "Crack-the-Whip", the kid in the middle doesn't feel anything, the kid on the end always wipes out.

Where did you get this theory? Please tell it to Felipe David, burn victim from the WTC basement (oh right you think a fireball that no one noticed or ever claimed to have seen destroy the lobby and the basements, it sure knew where to go to get right at those foundational columns!) Do you have any scientific evidence of this happening where columns have been cut and turn entire floors on the opposite end of the structure to rubble?

Zarabtul

12th July 2007 - 06:37 AM

[no sci-tech]

wcelliott

12th July 2007 - 06:42 AM

QUOTE

QUOTE (wcelliott @ Jul 11 2007, 07:11 AM)

When a structural member fails, it sends a shock wave through the remaining steel structure. This propagates at the speed of sound in steel, about 20,000feet/second, as a shock wave. Whereever that structure's bulk acoustic impedance changed, like at floors that were more solidly built (i.e., mechanical floors and basement), the shock wave would be reflected by the discontinuity. That reflection doubles the intensity of the shock wave. It's like "Crack-the-Whip", the kid in the middle doesn't feel anything, the kid on the end always wipes out.

Where did you get this theory?

Engineering Physics class, back in Engineering school.

It's a simple application of Transmission Line theory. It's also the basis, as I mentioned, of the primary failure mode of high-energy/high-reflectivity laser mirrors, except that's with light rather than sound.

And the shockwave would cause damage throughout the building that would propagate much faster than gravity does, which answers Newton's stupid question about "demolition waves" propagating faster than gravity.

einsteen

12th July 2007 - 09:32 AM

I fitted a parabolic function and found an acceleration of about 1.90h (with h the distance between two floors in meters and the result of course in m/s^2)

Assuming an error of one pixel in each measurement the difference between two points becomes an error of 2 pixels and if you take the ratio of an other squared difference the error counts really up in 2L/t^2 (although the average of the upper and lower value is still about 1.9h) and what is the value of h ? You have to know some details about the basis, heights etc. But taking h=3.7 the acceleration becomes 7.03 m/s^2 or 0.717g ignoring toppling...

NEU-FONZE

12th July 2007 - 12:28 PM

Einsteen:

Very nice work.... Living up to your name I see!

I presume your result is for WTC 1 and you allowed for perspective effects on the height? This will be a constant factor anyway (if you are ignoring tipping).

You should try your method on WTC 2, and perhaps you could also capture the tipping motion for that building.

einsteen

12th July 2007 - 01:54 PM

Yeah, it was better not to choose that nickname, but I use it too long now, but maybe I will change it, although we have a newton, a newtons bit elsewhere, a Max Photon I saw recently... Be careful I'm still a twoofer, will the twoof "virus" ever leave me...?

The toppling etc will be hard to capture I think, if anyone got ideas how to do that..?

newton

12th July 2007 - 04:59 PM

http://video.google.com/videoplay?docid=3898216904060714451

new video. lots of truth. uncomfortable truth, even for many CTers.

pods - yes.
flashes - yes.
no plane at the pentagon - yes.

physics arguments -yes.

adoucette

12th July 2007 - 06:01 PM

Now you believe in PODS and that there was no plane at the Pentagon?

ROTFLMAO

Way to go newton, you never disappoint.

Arthur

wcelliott

12th July 2007 - 07:37 PM

QUOTE

no plane at the pentagon - yes.

cough-cough-Short Bus! - cough-cough.

newton

12th July 2007 - 08:40 PM

professional soldiers, engineers, architects, pilots, and academics agree with me. your propaganda ridicule technique never fails to disappoint, either.

have a nice day, chuckling to yourselves.

adoucette

12th July 2007 - 08:46 PM

QUOTE (newton+Jul 12 2007, 03:40 PM)

professional soldiers, engineers, architects, pilots, and academics agree with me. your propaganda ridicule technique never fails to disappoint, either.

have a nice day, chuckling to yourselves.

I am having a nice day.

A good laugh always helps.

As to your "engineers, architects, pilots, and academics", let us know when one publishes something in an actual peer reviewed scientific journal.

Note: YouTube is NOT a peer reviewed scientific journal.

Arthur

Zarabtul

12th July 2007 - 08:55 PM

That's it run from the truth as fast as you can because we can't believe our govt. could make that large of mistake when they've been warned...

David B. Benson

12th July 2007 - 08:58 PM

QUOTE (einsteen+Jul 12 2007, 09:32 AM)

This is quite fine!

Some questions ---

How long is your record from collapse start to the end of your analysis?

How did you fit a parabolic function? By hand and eye, or some other technique?

How is it that h enters it to it? I can guess, but I'd like the read the details...

David B. Benson

12th July 2007 - 09:17 PM

QUOTE (memeticverb+Jul 12 2007, 05:27 AM)

Right, those numbers are given as the base load for the towers and weren't intended to show what was happening when th towers collapsed.

But how could one calculate the dynamic forces without a base to start with?

Is it possible to calculate the load distribution of a structure whose columns, one by one, are failing in a particular area?

(1) But those figures are wrong.

(2) It suffices to know the average DCR and the loads on the walls and core at the failure level. Both are available in NCSTAR1-6D.

(3) NIST does this in NCSTAR1-6D, at 10 or 20 minute intervals up to 100 minutes for WTC 1. Collapse commenced 2 minutes later. At that point, since the top block tilts south, treat the core as if it had only two super-columns, one in the north and one in the south. Since the additional load of three walls is a sudden load of infinite duration (as it is called in Simitses & Hodges) the DCR one calculates for the new overload is to be (nearly) doubled. The resulting dynamic DCR is between 2 and 3. This suffices to demonstrate that the structure must collapse.

roves shill

12th July 2007 - 10:08 PM

QUOTE (wcelliott+Jul 12 2007, 03:43 AM)

So, that is alot of words...... I guess that means no. You are not willing to back up your "planes demolished buildings" theory. I thought as much. Keep the faith Elliot.

RS

David B. Benson

12th July 2007 - 10:26 PM

QUOTE (roves shill+Jul 12 2007, 10:08 PM)

You are not willing to back up your "planes demolished buildings" theory.

I found he did quite well. Engineered objects need to be economical as well as safe.

And just what do you think would happen in WTC 1 when three walls buckle and the 33,200 tonne top block begins to tilt to the south?

wcelliott

13th July 2007 - 12:57 AM

QUOTE

You are not willing to back up your "planes demolished buildings" theory.

http://www.yourdictionary.com/ahd/p/p0648700.html

Since I can't teach you engineering, maybe I can increase your vocabulary:

Puerile - adj.
1. Belonging to childhood; juvenile.
2. Immature; childish.

synonyms:
Of or characteristic of a child, especially in immaturity: babyish, childish, immature, infantile, juvenile.

Or, I can just reciprocate: If you really believe what you claim to believe, then you should move to Afghanistan and join Al Qaeda.

Grumpy

13th July 2007 - 04:19 AM

newton

QUOTE

it's just that i don't like to limit myself to just the physics of 9/11, and OCTs get pissed about that. even the website owners are OCTs, and only tolerate me and the other CTers, because it would be an admission of guilt to simply ban us.

You mean like AE911truth.com banned everyone from their forum??? You won't get banned from this site simply for not knowing what you're talking about, you're still here, aren't you???

QUOTE (->

QUOTE

You mean like AE911truth.com banned everyone from their forum??? You won't get banned from this site simply for not knowing what you're talking about, you're still here, aren't you???

the gravitational potential of mass A, cannot crush mass 5(A). pretty simple. never mind in a factor of t1.3 over freefall.
a 47 seven storey building falls in 6.6 seconds over freefall, with limited structural damage to account for it. gravity cannot do that. gravity and fire together cannot do it.

See, you're allowed to post the stupidest statements, and then we are allowed to point out just how ignorant those statement truly are.

Yes, flying a plane into a building WILL cause it to eventually fall down, and if enough of that building fall on another building then that building too will fall down. Damage and fire WILL cause a building to fail, we've given you the evidence proving that and you give us none showing the use of explosives, etc. In science that means you lose the arguement.

QUOTE

your posts are insulting the intelligence of a large group of scholars and experts.

Would that be the same scholars who want to sell you that T-shirt or video??? Funny, I don't see anyone on my side that is trying to make money off the deaths of everyone on 911.

Or is that the same group of "scholars" who won't discuss anything on their forum with anyone who disagrees with them??? But I notice the online store is still open.

QUOTE (->

QUOTE

your posts are insulting the intelligence of a large group of scholars and experts.

Have you ever heard a snake oil salesman pitch you DIDN'T fall for???

QUOTE

professional soldiers, engineers, architects, pilots, and academics agree with me.

Yeah, there are IDIOTS in every profession, those that get out in front even make money off the rest of the flock(Jones, Fetzer, ect. at least until they start fighting over the money. The desperation they are showing is a good sign the sheep are getting wise.

Baaaa!!!

Grumpy

RealityCheck

13th July 2007 - 04:51 AM

QUOTE (newton+Jul 12 2007, 04:26 AM)

....
....
even the website owners are OCTs, and only tolerate me and the other CTers, because it would be an admission of guilt to simply ban us.....
....
....

Hi newton!

Long time no 'see'!

Is that the kind of 'two-step' dancing capability that defines the twoofer flock being fleeced like newborn rube by your twoofer 'pyramid scheme' cult leaders?

Please don't twist simple logic to the extent required to fit your persecution and other unhealthy complexes.

If the admin at Physorg were part of the 'conspiracy', they would ban you and NO-ONE would feel the loss. Sorry to burst the bubble of your 'importance' to those that are 'fleecing' you and your flockmates.

No amount of 'reverse psychology' rationalisations you come up with to supposedly 'explain' the TOLERANCE here at Physorg (as compared to twoofer 'fleecing' sites) will distract from the painfully obvious observation that your every such rational;isation is immediately and easily demolished by the simple truth that hardly anyone here (if any at all) is actually asking admin to ban you.

Which they WOULD if there was such an outcry as your posts MIGHT attract in a less tolerant site.

Besides, why would anyone here want to ban you?

You're a laugh-a-post....although I suspect that's not intentional sometimes, hehehe.

I for one look forward to dropping in and looking for a laugh....and of late you've been a mainstay to exercising my laugh muscles, mate! hehehe.

Take it easy with that twisted logic, newton....you'll strangle yourself in the end if you're not careful!

Cheers and keep it up, you naive little 'lamb' you.

And don't overuse your credit card with the "Baaa" sites.

RC.
.

memeticverb

13th July 2007 - 06:23 AM

QUOTE (wcelliott+Jul 12 2007, 06:42 AM)

So just for the record, lets get this theory right.

Fireballs raced through the center of the buildings, severely burning vast areas of the basement floors. Following and during this, a "shock wave" theoretically traveled through each column that was severed, and consequently turned the basements into rubble, parking lots included, smashing cars like tins cans, etc.

Yeah this is plausible.

Again, I ask simply where is evidence that this has ever happened in history? Has a steel column ever been severed before in a building that was not demolished with explosives? Is this the only case in the history of steel framed buildings collapsing to the ground, exhibiting all characteristics of demolition, coupled with dozens of eye-witnesses claiming demolitions, including fire fighters who said the fires were weakening?

If any of you govt apologists are really engineers and also genuinely believe that a steel-framed building could collapse like THIS, then I truly feel sorry for your employers.

newton

13th July 2007 - 07:43 AM

i am allowed to stay here, because i don't get too heated, and i try and play by the rules.

it's an emotional issue, and guys with veins popping out of their foreheads while they type are the ones who get banned.
the laws of civility, like the laws of newton, are pretty universal.

doesn't mean this site doesn't favour the mainstream media truth bulldozer.
sure seems like they do to me. i got two warnings cause i called arthurs an idiot once. i was lambasted with insults that would make a truckdriver blush, by 'palpatane'{b}SIC{b}, and bothered to complain, and nothing happened.
ditto elliot. i just complained, 'cause he's being a very uncivil, condescending man, and no warning, just a deletion of his most offensive comments.

bite my shiny metal arse, LOL!!!

the other reason i'm allowed to stay, is because i'm not as disappeared as some of the rest of you. it is better to assassinate my 'newton' chip body than merely ban it.

anyway, i was pretty hammered when i wrote those 'formulas', lol, but the basic idea is there.

another angle? .....

geometrically, a box cannot fit inside a box of equal size. when the top tilts, there is more surface area touching, because the top's on an angle, hence negating the need for a perfect alignment of top and bottom columns for impacts between perimeter columns. in other words, one hundred percent of the top perimieter columns are touching one hundred percent of the bottom columns.
and that is where the OCT loses.

wcelliott

13th July 2007 - 09:02 AM

QUOTE

ditto elliot. i just complained,

And called me a "hateful mass-murderer."

So much for "civility".

QUOTE (->

QUOTE

ditto elliot. i just complained,

And called me a "hateful mass-murderer."

So much for "civility".

when the top tilts, there is more surface area touching, because the top's on an angle, hence negating the need for a perfect alignment of top and bottom columns for impacts between perimeter columns. in other words, one hundred percent of the top perimieter columns are touching one hundred percent of the bottom columns.
and that is where the OCT loses.

Gee, I guess the construction workers were wasting their time, aligning those perimeter columns so that they were all vertical, when all they had to be was touching in order to support the 110 story building. Why use steel brackets, when friction will do the trick?

The reason you are still around, newton, is that you aren't smart enough to be dangerous.

Grumpy

13th July 2007 - 01:44 PM

newton

Whether or not you are an idiot I do not claim to know. But the stuff you post IS truly idiotic.

No plane at the Pentegon??? An incredibly stupid assertion not worthy of further comment.

Pods on aircraft??? Yeah, the landing gear pods and a puny little missile will do what a 125 ton aircraft won't??? Not in the real world!!!

Flashes??? So what???

And the web sites which spread this garbage are those same websites asking for your money!!! (Yeah, take some sandwiches for lunch for some engineers, no less!!!)

WTC 1 and 2 fell because the damage done by the aircraft left them vulnerable to the massive fires. WTC 3,4,5,6 and 7 were destroyed because debris from 1 or two or both fell on them, it's not really hard to understand, it's what we all saw and making crap up about it will not change the simpliest explanation, nor will the lies told by the CTer clowns, but it does sell T-shirts and videos to the sheep, they'll buy anything!!!

Baaa!!!

Grumpy

wcelliott

13th July 2007 - 02:12 PM

QUOTE

And the web sites which spread this garbage are those same websites asking for your money!!!

I couldn't care less that they're being fleeced by these liars, that, to me is just the economic version of Darwin's Theory.

What I care about is that the lies being spread *are* being swallowed whole by some people who are inevitably going to end up killing people because they truly believe this crap.

Take Malmo, for instance. We couldn't talk *any* sense to him, he was so brainwashed that whenever there was a fundamental physical principle that proved his theory wrong (e.g., thermal expansion of steel), he'd deny that principle existed, claiming it was all part of the vast NWO conspiracy. That's a hallmark symptom of paranoid schizophrenia.

And *that's* what they're selling. It isn't harmless, it's destroying peoples' minds, leading them into fear and hate and delusion, and ultimately, madness. Paranoia doesn't require a chemical imbalance in the brain, nor structural abnormalities, those get created as the brain accepts a lie and the rest of the mind restructures to accept its implications.

That people do this to others deliberately, whatever their motive, is pure evil.

einsteen

13th July 2007 - 02:44 PM

DBB,

A function y= -factor *x^2 has been created with maple until it fits on the picture, see below, there are programs to make white transparant when you paste it on an other picture and that was what I did

user posted image

The nice thing of a parabole of course is that we don't have to wonder about the maple values, under scaling it still is a parabole.

I will redo it later for a bigger time interval (if possible) and then we could probably also see that the parabolic behavior is only in the beginning.

This is roughly: by simply counting pixels.

Horizontally 67 pixels means a time period of t=67/29.97 seconds in which it falls a distance
of 69 pixels. Since one story is 58/4 pixels that means it falls a distance L=69*4*h/58 in that time

The acceleration then is 2L/t^2=2*69*4*h*29.97^2/(58*67^2)=1.9043h
and therefore the h is part of it.

A nitpicker would say acceleration=f1 * h, with f1=1.9043 /s^2 .....

btw a real professional method would of course be using techniques like least squares etc but I don't think that a very precise value is needed, it is about the order of course

newton

13th July 2007 - 03:15 PM

pretty brilliant, einsteen.

wcelliot, when the top tilts, the columns don't need to be aligned to touch. the point being, that the perimeter doesn't only need to destroy the floor truss seats, as the OCTs keep braying. the top doesn't fit inside the bottom.

i don't remember calling you a hateful mass murderer. could you link me to that post?

carterelliott

13th July 2007 - 04:21 PM

QUOTE

i don't remember calling you a hateful mass murderer. could you link me to that post?

It's under the "Review/Add Feedback" under my normal screen-name. (Not this one.)

NEU-FONZE

13th July 2007 - 05:59 PM

Einsteen:

Is it really parabolic?

It's hard to tell from your small-scale image but it kinda looks like the curve becomes almost linear after a while.....

There is no physical constraint that says the curve must be of the form y = at^n over a wide range of t. The collapse mechanism could change and you might find a better fit using different functions for small and large t ...... just a suggestion.....

adoucette

13th July 2007 - 06:29 PM

QUOTE (newton+Jul 13 2007, 10:15 AM)

i don't remember calling you a hateful mass murderer.

One would think that one would not refer to someone as a "Hateful mass-murderer" lightly and even more, that one would not then forget that one had done so.

Arthur

wcelliott

13th July 2007 - 06:37 PM

QUOTE

One would think

One would think.

einsteen

13th July 2007 - 09:41 PM

Every curve around x=0 is of course

f(x)=f(0)+f'(0)x+(1/2)f''(0)x^2+O(x^3)

but it is of course the difficulty to determine the factors.

Here is a picture to play with, I added also some intact stories to make it more precise

http://img511.imageshack.us/my.php?image=anothertp8.png

We see that the decay is faster than parabolic, that will of course be because when a floor is demolished we get

a=g-E1_demolished/h*Mcollapse

David B. Benson

13th July 2007 - 09:59 PM

QUOTE (memeticverb+Jul 13 2007, 06:23 AM)

Fireballs raced through the center of the buildings, severely burning vast areas of the basement floors.

Following and during this, a "shock wave" theoretically traveled through each column that was severed,

and consequently turned the basements into rubble, parking lots included, smashing cars like tins cans, etc.

Again, I ask simply where is evidence that this has ever happened in history? Has a steel column ever been severed before in a building that was not demolished with explosives?

Is this the only case in the history of steel framed buildings collapsing to the ground,

exhibiting all characteristics of demolition,

coupled with dozens of eye-witnesses claiming demolitions,

including fire fighters who said the fires were weakening?

(1) Yes, eyewitness accounts.

(2) Yes, and witness accounts can be interpreted so.

(3) No evidence for this.

(4) Grumpy used to post pictures of a radio telescope which progressively collapsed, although that was, strictly speaking, not a building. But it certainly was a steel structure which fell apart on the way down to the ground.

(5) The towers fell via crush-down. Demolition is down via crush-up. Looks quite different.

(6) No, the witness accounts state they hear explosions, a short-hand for explosive sounds. Not demolitions.

(7) No fire fighters stated that the fires were weakening. NIST's fire study states this. But it doesn't matter, because once steel is sufficiently heated, it has lost its strength and never regains it.

David B. Benson

13th July 2007 - 11:14 PM

QUOTE (newton+Jul 13 2007, 03:15 PM)

pretty brilliant, einsteen.

For once I agree with poster newton.

einsteen was certainly inspired!

Daru

13th July 2007 - 11:55 PM

Study from Pilots for 9/11 Truth: No Boeing 757 hit the Pentagon

Pilots for 9/11 Truth obtained black box data from the government under the Freedom of Information Act for AA Flight 77, which The 9/11 Report claims hit the Pentagon. Analysis of the data contradicts the official account in direction, approach, and altitude. The plane was too high to hit lamp posts and would have flown over the Pentagon, not impacted with its ground floor. This result confirms and strengthens the previous findings of Scholars for 9/11 Truth that no Boeing 757 hit the buillding.

Madison, WI (PRWEB) June 21, 2007 - A study of the black box data provided by the government to Pilots for 9/11 Truth has confirmed the previous findings of Scholars for 9/11 Truth that no Boeing 757 hit the Pentagon on 9/11. "We have had four lines of proof that no Boeing 757 hit the building," said James Fetzer, founder of Scholars for 9/11 Truth. "This new study by Pilots drives another nail into a coffin of lies told the American people by The 9/11 Commission"

news.yahoo.com/s/prweb/20070621/bs_prweb/prweb534642_1

NO BOEING AT THE PENTAGON.

Period.

David B. Benson

14th July 2007 - 12:06 AM

QUOTE (Daru+Jul 13 2007, 11:55 PM)

"We have had four lines of proof that no Boeing 757 hit the building," said James Fetzer, founder of Scholars for 9/11 Truth.

What a fool.

Seeing is believing. I've seen pictures of American Airline airplane parts on the Pentagon lawn and embedded in the wall.

--- But in any case, take all this Pentagon nonsense to a thread or forum devoted to that topic. We are specialists here. Just the World Trade Center.

Daru

14th July 2007 - 12:28 AM

The wtc case is simple. Very simple. The towers were blown up. Explosives were used.

Only thing one have to know is 2 + 2 = 4 ... NOT 5 or 6

Thats all. Very simple.

Have a good day mister.

David B. Benson

14th July 2007 - 12:52 AM

QUOTE (Daru+Jul 14 2007, 12:28 AM)

Explosives were used.

Have a good day mister.

No evidence for it, despite the FBI and BATF looking.

No evidence for it, from the Blanchard report.

NIST explains, in great detail, how the aircraft impacts plus fires eventually destroyed the ability of the towers to stand.

And now, a good theory, based on physics and material properties, exists to explain the evolution of the actual progressive collapses.

Thank you. The same to you.

wcelliott

14th July 2007 - 04:17 AM

QUOTE

Thats all. Very simple.

From the "if it doesn't fit, force it" school of debate.

adoucette

14th July 2007 - 05:13 AM

QUOTE

A study of the black box data provided by the government to Pilots for 9/11 Truth has confirmed the previous findings of Scholars for 9/11 Truth that no Boeing 757 hit the Pentagon on 9/11.

ROTFLMAO

I'm glad the two groups agree, it makes them both laughable.

Arthur

Zarabtul

14th July 2007 - 06:25 AM

that is cute... maybe they should work on that some more...

newton

14th July 2007 - 06:32 AM

QUOTE (wcelliott+Jul 13 2007, 06:37 PM)

One would think.

it's a big world. i meet a lot of people.

anyway, there was no emotion in my factual statement, which was based on the quote...

QUOTE

from wcelliot....
I'm proud of it, and I am personally gratified every time I hear that one of the weapons systems I helped design does its job and sends more of you and yours to their graves.

pretty hateful mass murdering admitted to there, if you ask me. i forgot that you were a weapons designer who takes 'pleasure' in the mass execution of innocents.

back on topic, now?

david, i think we've agreed on other things, too. you actually only sit on facts that are facts, for the most part, and don't try and pass off wild speculation as fact, like many other OCTs, do.

i've never heard you say something PUERILE, like, "planes hit buildings, buildings fall down go boom".

RealityCheck

14th July 2007 - 06:33 AM

.
Hi all!

It bears repeating....

(1) The steel only had to be hot enough to lose its 'tempering' properties in order to lose its 'design' strength....it was not necessary that they should get anywhere near 'melting' temperatures;

and....

The staggered and differential and totally uncontrolled COOLING and MIGHTY CONTRACTION/DISTORTION processes and FORCES AFTER the fires' heating front passed would have been the 'coup de grace' for whatever 'strength' stability was left;

and newton....

The top section columns eventually HIT the bottom section columns, they didn't just 'TOUCH' them lovingly. And glad to hear you're not going to insult anyone by repeating debunked matter....or else some may call you an ---- again! hehehe.

Cheers until my next laughter break, guys!

PS: How goes it Grumpy!? Traded in that souped up wheelchair yet?hehehe.

RC.
.

wcelliott

14th July 2007 - 07:02 AM

QUOTE

who takes 'pleasure' in the mass execution of innocents.

back on topic, now?

Not quite. I stated that I took personal pleasure whenever a weapons system I worked on DID ITS JOB PROPERLY, which means, was used against ENEMY COMBATANTS in war.

ENEMY COMBATANTS KILLED IN BATTLE (whom you'd identified yourself with, which drew the comment) are NOT "INNOCENTS" being "MASS EXECUTED".

It's puerile statements like that cause me to wonder whether you took the SHORT BUS to school.

And should anyone wonder how the "puerile" definition came up, it was in response to that idiotic argument asserting that if I actually believed that airplanes alone were all it took to destroy the WTC towers, that I should go buy junked planes from the Mojave boneyard and go into business using them for CDs, and that the fact that I didn't, meant that I wasn't "putting my money where my mouth was" or however he'd phrased it. It was such a stupid remark, that I didn't feel it was worthy of discussion.

And since some here who've claimed to "grok physics" have made so many stupid remarks, I've adopted Grumpy's approach of synopsizing the argument into as few words as possible, usually when one of my longer narratives has gone over their heads.

By the way, I still stand by my point that deliberately misleading people causing them to become paranoid is pure evil. You're either incredibly dense or truly evil. Pick one.

Capracus

14th July 2007 - 10:18 AM

QUOTE (Daru+Jul 13 2007, 11:55 PM)

Another case of eyewitness accounts at odds with the interpretation of aviation flight data. Now where have we seen this before?

http://forum.physorg.com/index.php?showtop...ndpost&p=154158

Chainsaw,

14th July 2007 - 01:17 PM

QUOTE (Daru+Jul 14 2007, 12:28 AM)

The wtc case is simple. Very simple. The towers were blown up. Explosives were used.

Only thing one have to know is 2 + 2 = 4 ... NOT 5 or 6

Thats all. Very simple.

Have a good day mister.

Please explain to me what explosives, I just manufactured Nano thermites-thermates and put them to the test, so what explosives do you think would survive?
I have tested all known compounds in a similar environment, please show me where some one else say from the truth movement has done test to see if explosives survive, you can show me this can you not?
Nano thermites are more Chemically and Sono Chemically reactive than Thermites.
The only way to make Nano thermites less chemically reactive is to increase the oxide layer at the expense of the aluminum fuel layer, doing so means that the Nano thermite that are stable would not blow your nose.
This is something that the advocates of Controlled Demolition should have tested years ago instead of waisting our time.
I Would like to see evidence of explosive survival from any honest person who has done the research into the field, I could be wrong and freely admit that, but who else has even tried to do the real world experiments?

wcelliott

14th July 2007 - 04:35 PM

QUOTE

Another case of eyewitness accounts at odds with the interpretation of aviation flight data.

I think it's the "interpretation of the data" that's the problem here.

Flight data recorders just record the data that the instruments provide. If the avionics aren't zeroed-in properly, they'll provide data that's inaccurate, and the flight data recorder will record the inaccurate data.

Another point to consider is what altitude is the altimeter reading? The altitude of the nose of the aircraft or the altitude of the tail? Seems like a dumb question until you realize that the airplane was in a dive when it hit the Pentagon.

And in any case, I wouldn't take the flight recorder's word for the aircraft "missing" the Pentagon. There was plenty of damage to the Pentagon, and lots of debris inside and out, all from the aircraft that was hijacked. Lots of commuters saw it hit, nobody saw it fly away, nobody saw a missile.

2+2=4.

TBX

14th July 2007 - 07:12 PM

I thought this was an interesting pdf on the synthesis of nanocomposites.

http://www.llnl.gov/tid/lof/documents/pdf/307362.pdf

It would seem that some of the redox reactions mentioned in here contributed to the collapse...

wcelliott

14th July 2007 - 08:50 PM

QUOTE

It would seem that some of the redox reactions mentioned in here contributed to the collapse...

Other than the fact that the process described in the paper for making the nanothermate didn't exist until three years after 9/11...

What makes you think any explosives were needed in the first place? The plane impacts and subsequent fires were more than sufficient to drop the towers.

Also, close observation of the structures in the time between impact and collapse showed they were progressing-to-failure continuously, so at what time would the explosives have been used? Pick any time, and you'll find the same dynamics were occurring before that time, too, right up to the impact of the aircraft.

There's nothing consistent with explosives use in the collapse of the towers, and everything observed was consistent with impact-damage-plus-fire.

TBX

14th July 2007 - 09:08 PM

I said nothing about explosives being used.

Chainsaw,

14th July 2007 - 09:22 PM

QUOTE (TBX+Jul 14 2007, 07:12 PM)

Since I used that very process to test nano thermites, and thermates and they have one problem stability, what is your point?

I tested them to similar conditions in and near the impact and fire zones and that would have occurred in Building 7. To make the particles less reactive and survive in the environment you have to thicken the oxide layer as expense of the fuel layer that severely limits the reactivity of he Compounds, they fizzle instead of producing super sonic shock waves.
A is a standard aluminum particle, B is a slightly smaller particle. When you get to nano thermite size the particles can either be highly reactive or highly stable dependent on the thickness of the oxide layer. The highly stable particles are low on fuel, the highly reactive particles are to unstable to survive.
Particle C is stable but low on fuel, particle D is unstable and highly reactive it also has a high energy value but will not survive well under the conditions in the buildings.
User posted image

Chainsaw,

14th July 2007 - 09:28 PM

QUOTE (TBX+Jul 14 2007, 09:08 PM)

I said nothing about explosives being used.

I agree you did not mention explosives, I would like to hear more on this, I have been doing similar experiments and come to similar conclusions.
I have preformed several reduction experiments, however the most promising have been Zinc Chloride, Sulfate, and Hydrogen reactions.
I would like to know more of what your suggesting.

TBX

14th July 2007 - 09:39 PM

My point was that explosives wouldn't have been needed given the massive initial explosion and subsequent high temperature chemical reactions.

Chainsaw,

14th July 2007 - 11:34 PM

QUOTE (TBX+Jul 14 2007, 09:39 PM)

My point was that explosives wouldn't have been needed given the massive initial explosion and subsequent high temperature chemical reactions.

That is a conclusion that I have reached as well, thanks I just thought you were commenting on my Nano thermite research.
I sincerely appreciate your Ideas on this, thanks.

adoucette

14th July 2007 - 11:49 PM

QUOTE (TBX @ Jul 14 2007+ 09:39 PM)

My point was that explosives wouldn't have been needed given the massive initial explosion and subsequent high temperature chemical reactions.

QUOTE (Chainsaw+,Jul 14 2007, 06:34 PM)

That is a conclusion that I have reached as well,

What "Massive Initial Explosion" are you two talking about?

Arthur

David B. Benson

15th July 2007 - 01:46 AM

Arthur --- When were you promoted to respice finem?

Congratulations!

adoucette

15th July 2007 - 02:33 AM

That would be SELF promotion.

Arthur

Chainsaw,

15th July 2007 - 03:50 AM

QUOTE (adoucette+Jul 14 2007, 11:49 PM)

[/QUOTE]
What "Massive Initial Explosion" are you two talking about?

Arthur

adoucette

15th July 2007 - 04:24 AM

[QUOTE=Chainsaw,,Jul 14 2007, 10:50 PM] What "Massive Initial Explosion" are you two talking about?

Arthur [/QUOTE]
A huge air fuel blast aided by liquid burning metals, making it more thermobaric like, and then the reactions that follow that! Creating moderate amounts of super heated molten aluminum oxide.
The planes component included Aluminum, Magnesium, and titanium. [/QUOTE]
Except the original "air fuel blast" on the impact floors was way too fuel rich to generate very much blast. (unlike in say the elevator shafts). So while there was a mild over-pressurea on those floors (hense the relatively slowly expanding fireball) there wasn't even enough over-pressure to blow out the windows.

So, NO, there was NO evidence of a THERMOBARIC explosion on the impact floors, from fuel or aluminum or otherwise.

And while there MAY have been some super heated Aluminum Oxide, I would think that the CHANCE of it being in sufficient quantities and then near sufficient structural members to make any difference at all in the outcome of the towers is SO SLIM as to be totally irrelevent.

Arthur

reasonwhy

15th July 2007 - 06:14 AM

This must be were Arthurs and wcelliott post when not working here:

http://fredthompsonforum.com/

The forums understanding of politics and the reason for 9/11 is much better than the standard OCT’er ignorance shown on this forum.

wcelliott

15th July 2007 - 06:32 AM

Just because we aren't as gullible as the CDiots, and understand more physics than you do, doesn't mean we're ignorant of politics.

Cynicism only passes for wisdom among the inexperienced. Experienced people know the difference.

Go learn something and get back to us.

Chainsaw,

15th July 2007 - 12:20 PM

QUOTE (adoucette+Jul 15 2007, 04:24 AM)

A huge air fuel blast aided by liquid burning metals, making it more thermobaric like, and then the reactions that follow that! Creating moderate amounts of super heated molten aluminum oxide.
The planes component included Aluminum, Magnesium, and titanium. [/QUOTE]
Except the original "air fuel blast" on the impact floors was way too fuel rich to generate very much blast. (unlike in say the elevator shafts). So while there was a mild over-pressurea on those floors (hense the relatively slowly expanding fireball) there wasn't even enough over-pressure to blow out the windows.

So, NO, there was NO evidence of a THERMOBARIC explosion on the impact floors, from fuel or aluminum or otherwise.

And while there MAY have been some super heated Aluminum Oxide, I would think that the CHANCE of it being in sufficient quantities and then near sufficient structural members to make any difference at all in the outcome of the towers is SO SLIM as to be totally irrelevent.

Arthur

thermobaric like, You do know do you not Arthur that molten aluminum Oxide traveling though the air can make steel into swiss cheese do you not?
There is evidence that the initial fireball had thermobaric like traits, although it was not quite a true thermobaric.
You have done impact studies now Author that show this to be true?

QUOTE

And while there MAY have been some super heated Aluminum Oxide, I would think that the CHANCE of it being in sufficient quantities and then near sufficient structural members to make any difference at all in the outcome of the towers is SO SLIM as to be totally irrelevant.

Because I have found just the opposite to be indicated by actual impact studies!

Once The oxide coating on aluminum is compromised it will oxidize with any source of oxygen, even burning Jet fuel and it creates temperatures well over 2800c, the then hot aluminum oxide does macro and micro damage to the steel and leaves it more reactive to Chlorides and Sulfates!
After all molten Aluminum oxide will melt steel, and solid aluminum oxide traveling though the air will penetrate steel like a knife though Jello.

Please give me the benifit of your knowledge on the impact tests you have done.

NEU-FONZE

15th July 2007 - 12:45 PM

Chainsaw:

Yes, I agree thith you, I think fine aluminum particulate was created by the aircraft impacts and this would give the fuel-air mixture some thermobaric explosive characteristics.

I notice that Arthur has always tried to play down the severity of the impact explosions... I am not sure why!

adoucette

15th July 2007 - 01:54 PM

QUOTE (Chainsaw+)

thermobaric like

Sorry, there is no evidence to suggest that the initial fireball was in any way thermobaric like. The fuel did not get a chance to mix with sufficient oxygen to create thermobaric type properties. Simple math: Too much fuel, too little air. The only evidence of thermobaric conditions were in limited areas like the elevator shafts where smaller quantities of fuel were mixed with large volumes of air (The fuel would have been initially forced into the shafts via kinetic energy but then mixed with air by gravity) did these explosive mixtures naturally occur. Added from your reference sited below

QUOTE

Flame propagation speed has a significant influence on the blast parameters both inside and outside the source volume. High flame front speeds and resulting high blast over pressures are seen in accidental vapor cloud explosions where there is a significant amount of confinement and congestion that limits flame front expansion and increases flame turbulence.

Even so, there is no evidence at all that these relatively small fuel/air explosions did any significant structural damage to the towers.

QUOTE (->

QUOTE

Even so, there is no evidence at all that these relatively small fuel/air explosions did any significant structural damage to the towers.

Chainsaw:

Yes, I agree thith you, I think fine aluminum particulate was created by the aircraft impacts and this would give the fuel-air mixture some thermobaric explosive characteristics.

I notice that Arthur has always tried to play down the severity of the impact explosions... I am not sure why!

The ISSUE gentlemen is this:

Did the AIRPLANE IMPACT actually create SUBSTANTIALLY MORE damage via these chemical reactions than the NIST IMPACT analysis indicated.

While you have both implied that it did, you have shown NO QUANTITATIVE evidence of any sort that it did, nor have you shown any LOGIAL data to conclude that it should have, nor have you shown any VISUAL evidence of the towers POST IMPACT that would indicate that YOUR analysis is MORE ACCUATE than the NIST one. (In this regard, remember to consider that the NIST fire and impact cases resulted in a slightly HOT result, in both cases the models progressed to the point of collapse a bit faster than the actual towers)

So while I appreciate both of you explaining why the CHEMICAL/REACTIVE nature of the impact/fire would likely ADD additional ENERGY to that which the impact/fire released, I have yet to see ANY CONVINCING EVIDENCE that the AMOUNT of energy added from these chemical reactions was such a SIGNIFICANT fraction of the TOTAL ENERGY RELEASED during the impact/fires as to significantly alter the outcome.

If either of you think you have identified a SIGNIFICANT source of additional energy that should have been considered in the Collapse Scenario, then please, state its source precisely and quantify it as precisely as you can (and tell NIST about it).

For example by what quantity (and at what time) would you change NIST's estimates that 8,000 GJ of heat energy (with a peak plateau of 2 GW) was released by the fires in WTC 1 and that 3,000 GJ of energy (with a peak plateau of 1 GW) was released by the fires in WTC 2?

See NIST NCSTAR 1-5 EX Sum pg xlvi

or

By what quantity would you change NIST's estimates of floor and column damage in NIST NCSTAR 1-6 fig 5-13 (case A - WTC 1) or fig 5-16 (case B - WTC 2) pgs 135-138 or and fig 5-19 (case C - WTC 2) or fig 5-22 (case D - WTC 2) pgs 141-144?

I believe the MOST convincing evidence that these chemical reactions were NOT a substantial issue is the general agreement NIST gets with its very detailed impact studies and the visual/physical evidence and secondly the fact that BOTH towers were stable AFTER the impact and remained so until they were SLOWLY damaged by the fires.

Arthur

Daru

15th July 2007 - 02:04 PM

"Although dramatic, these fireballs did not explode or generate a shock wave. If an explosion or detonation had occurred, the expansion of the burning gasses would have taken place in microseconds, not the 2 seconds observed. Therefore, although there were some overpressure, it is unlikely that the fireballs, being external to the buildings, would have resulted in significant structural damage. It is not known whether the windows that were broken shortly after impact were broken by these external overpressures, overpressures internal to the building, the heat of the fire, or flying debris."
www.fema.gov/pdf/library/fema403_ch2.pdf

Jet fuel is not an explosives... and FEMA knows that ...obviously.

What does Nist say. I have not find it.

But the problem is that when I look at the 2.tower impact videos... then it looks to me like a massive explosion.

(And I dont buy "A huge air fuel blast aided by liquid burning metals, making it more thermobaric like" theory... it sounds like a wild conspiracy theory to me)

Chainsaw,

15th July 2007 - 02:10 PM

QUOTE (NEU-FONZE+Jul 15 2007, 12:45 PM)

I think he simply is confusing the terms thermobaric like with themobaric, an explosion can be themobaric like, and not be a true themobaric.
I believe that Arthur has misconceptions as to what we are actually proposing which is an actual reason for the effects on the fire proofing and the huge extent of damage to the core columns. As well as the explosions down the elevator shafts and in the basements without thermobaric like effects those events would not have occurred or been as wide spread.
This gives a good discription of thermobarics,

http://www.storysmith.net/Articles/Blast%2...nd%20rounds.pdf

I must also point out that damage from hot particulate matter to the columns in the core would cause the core columns to be weaker than the perimeter columns so once the tilt was arrested at wedge in the core columns could not sustain the weight load in compression on the hinge and the collapse goes from Asymmetrical to Symmetrical because the core columns are no longer dissipating energy in tension, via motion along the hinge joint so they transfer that motion into compression on the weakened sections of the columns that then fail destroying the hinge joint allowing the top block to fall according to its center of mass in a direct line to the center of the earth.

Sorry I have been rereading Principia by sir Newton.

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