15th Anniversary of 9/11 Megathread

NIST_Report · 9時間前

Hello all,

Dr. Robert Korol, professor emeritus of civil engineering at McMaster University in Hamilton, Ontario, and a fellow of the Canadian Society for Civil Engineering, has led a team of academic researchers in preparing two peer-reviewed scientific papers on the destruction of World Trade Center Building 7. Both papers were published in the Challenge Journal of Structural Mechanics — the first one in July 2015, the second in February 2016.

Paper 1: Performance-based fire protection of office buildings: A case study based on the collapse of WTC 7

http://www.challengejournal.com/index.php/cjsmec/article/view/36/19

Paper 2: The collapse of WTC 7: A re-examination of the “simple analysis” approach

http://www.challengejournal.com/index.php/cjsmec/article/view/50/41

The reason these peer-reviewed papers are significant is because the official agency tasked with investigating the 3 collapses on 9/11 has refused to release their model data for peer review.

NIST omitted stiffeners in their analysis
NIST omitted shear studs
NIST did not follow N.F.P. investigation protocol

According to NIST, they will not release the following information:

All input and results files of the ANSYS 16-story collapse initiation model with detailed connection models that were used to analyze the structural response to thermal loads, break element source code, ANSYS script files for the break elements, custom executable ANSYS file, and all Excel spreadsheets and other supporting calculations used to develop floor connection failure modes and capacities.

and

All input files with connection material properties and all results files of the LS-DYNA 47-story global collapse model that were used to simulate sequential structural failures leading to collapse, and all Excel spreadsheets and other supporting calculations used to develop floor connection failure modes and capacities.”

David Topete, MSCE, Structural Engineer, explains further: https://youtu.be/v9WB1A9j8f8?t=15s

Mr. Topete discusses how WTC Building 7's column 79's failure could not have caused the symmetrical and simultaneous collapse into it's own footprint.

If you aren't familiar with the report's omissions,

Technical Statement: NIST maintains that WTC7 collapsed due to fire acting upon the 13th floor A2001 girder between columns 79 and 44 and the beams framing into it from the east. They said that the beams expanded by 5.5” (revised in June 2012 to 6.25”), broke the girder erection bolts, and pushed this girder off its column 79 seat. This girder fell to floor 12, which then precipitated a cascade of floor failures from floor 12 down to floor 5, and column 79 then became unsupported laterally, causing it to buckle. It is then said that column 79's buckling caused the upper floors to cascade down, which started a chain reaction—a north-to-south then east-to-west horizontal, progressive collapse—with a global exterior collapse that was captured on the videos.

The first omission concerns flange-to-web stiffeners on the south end of the girder (A2001).

See drawing 9114

These omitted stiffeners would prevent the girder flange from folding when the girder web moved beyond the seat, requiring twice the possible expansion of the beams framing into the girder from the east to move the girder far enough to the west for it to fall off its seat.

Here's 30+ year engineering professional Kamal Obeid, C.E., S.E., to help explain:

https://youtu.be/3WCcSHpvAJ8?t=15s

Again, the problem is the official report cannot be peer reviewed, specifically the model data. This model data was used to support their entire theory, which still does not account for the global free fall acceleration of the building that NIST attempted to overlook until corrected at their public draft hearing in 2008.

This video series was created by the physics teacher who corrected NIST's findings, making them modify their report to include free fall in the collapse:

The NIST report on Building 7 cannot be peer reviewed until the model data is released.

Until then, a two-year study using finite element modeling to evaluate the possible causes of the collapse is underway by Dr. J Leroy Hulsey, Chair of UAF's Civil and Environmental Engineering Department, and two Ph.D. research assistants: www.WTC7Evaluation.org

These models will be released in the public domain in 2017.

^edit: ^Thank ^you ^{/u/raoulduke25} ^and ^mods ^for ^allowing ^a ^technical ^discussion. ^I ^appreciate ^this ^thread ^- ^have ^a ^good ^night.

JTRIG_trainee · 9時間前

How can anyone claim the collapse of WTC7 was progressive, when it is observed to collapse straight down at free fall acceleration?

In order to achieve free fall acceleration (confirmed by NIST for over 8 stories) ALL column support must be removed simultaneously.

How can you have simultaneous removal of all column support in a progressive collapse? It's impossible. There is no possible mechanism of progressive collapse that can demonstrate to produce the observed free fall acceleration.

This is only one of many pieces of solid evidence pointing to explosive demolition for all three buildings.

Greg_Roberts_0985 · 3時間前

Jet fuel can't melt steel beams, so why was there molten metal at the WTC collapse sites?

NIST claims that WTC 1&2 collapsed due to jet fueled fires (just normal offices fires for WTC7) which were not hot enough to produce molten steel or iron, but also claim that if there had been molten steel or iron in the debris afterwards, it would have been irrelevant to the cause of the collapses. The evidence of molten steel or iron cannot be called “irrelevant,” given the fact that the building fires, as NIST pointed out, cannot explain it.

Physical Evidence

Steel – which has a melting point of 2,800 degrees Fahrenheit – may weaken and bend, but does not melt during an ordinary office fire. Yet metallurgical studies on WTC steel brought back to WPI reveal that a novel phenomenon – called a eutectic reaction – occurred at the surface, causing intergranular melting capable of turning a solid steel girder into Swiss cheese.

Stating that the New York Times called these findings “perhaps the deepest mystery uncovered in the investigation,” the article added:

A one-inch column has been reduced to half-inch thickness. Its edges – which are curled like a paper scroll – have been thinned to almost razor sharpness. Gaping holes – some larger than a silver dollar – let light shine through a formerly solid steel flange. This Swiss cheese appearance shocked all of the fire-wise professors, who expected to see distortion and bending – but not holes.

In May 2004, the RJ Lee Group issued a report, entitled “WTC Dust Signature,” at the request of the Deutsche Bank, in order to prove (to its insurance company) that the building was “pervasively contaminated with WTC Dust The report listed five elements in this signature, one of which was: “Spherical iron and spherical or vesicular silicate particles that result from exposure to high temperature
In 2005, the United States Geological Survey (USGS) published a report entitled “Particle Atlas of World Trade Center Dust,” which was intended to aid the “identification of WTC dust components.” Among the components, it reported, were “metal or metal oxides” (which could not be distinguished by the USGS’s methods). “The primary metal and metal-oxide phases in WTC dust,” the report said, “are Fe-rich [iron-rich] and Zn-rich [zinc-rich] particles
Extremely high temperatures during the World Trade Center destruction
Journal of the American Society of Safety Engineers

The debris pile at Ground Zero was always tremendously hot. Thermal measurements taken by helicopter each day showed underground temperatures ranging from 400ºF to more than 2,800ºF
Sources related to exceptionally high temperatures, and/or to persistent heat at Ground Zero
FEMA documents in their Appendix C of its May 2002 WTC Building Performance Assessment Team study, for sample 1, “evidence of a severe high temperature corrosion attack on the steel, including oxidation and sulfidation with subsequent intergranular melting.” A “sulfur-rich liquid” containing “primarily iron, oxygen, and sulfur” “penetrated” into the steel.

Testimonial Evidence

Testimony from Firefighters:

Testimony from Other Professionals:

Leslie Robertson, a member of the engineering firm that designed the World Trade Center, said 21 days after the attack: “When we were down at the B1 level, one of the firefighters said, ‘I think you’d be interested in this,’ and they pulled up a big block of concrete and there was a, like a little river of steel, flowing.”
Ron Burger, a public health advisor at the National Center for Environmental Health who arrived at Ground Zero September 12, 2001, said: “Feeling the heat, seeing the molten steel, the layers upon layers of ash, like lava, it reminded me of Mt. St. Helen’s and the thousands who fled that disaster.”
In late fall 2001, Dr. Alison Geyh of the Johns Hopkins School of Public Health reported: “Fires are still actively burning and the smoke is very intense. In some pockets now being uncovered, they are finding molten steel.”
Joe Allbaugh, the Director of FEMA, said in an October 2001 interview on CBS: “It’s just too hot for rescuers to get into [some] areas. So we do not know yet what’s in those areas, other than very hot, molten material.”
Dr. Keith Eaton reported in Structural Engineer: “They showed us many fascinating slides . . . ranging from molten metal which was still red hot weeks after the event, to 4-inch thick steel plates sheared and bent in the disaster.”
Don Carson, a hazardous materials expert from the National Operating Engineers Union, said six weeks after 9/11: “There are pieces of steel being pulled out from as far as six stories underground that are still cherry red.”
OSHA respond to the underground fires and potential steam explosions

Underground fires burned at temperatures up to 2,000 degrees. As the huge cranes pulled steel beams from the pile, safety experts worried about the effects of the extreme heat on the crane rigging and the hazards of contact with the hot steel. And they were concerned that applying water to cool the steel could cause a steam explosion that would propel nearby objects with deadly force. Special expertise was needed. OSHA called in Mohammad Ayub and Scott Jin, structural engineers from its national office, to assess the situation. They recommended a special handling procedure, including the use of specialized rigging and instruments.

Testimony from Other Credible Witnesses:

Greg Fuchek, vice president of a company that supplied computer equipment used to identify human remains, reported that “sometimes when a worker would pull a steel beam from the wreckage, the end of the beam would be dripping molten steel.”
Sarah Atlas, of New Jersey’s Task Force One Urban Search and Rescue, arrived at Ground Zero on September 11 and reported that “fires burned and molten steel flowed in the pile of ruins still settling beneath her feet.”
Tom Arterburn, writing in Waste Age, reported that the New York Department of Sanitation removed “everything from molten steel beams to human remains

Videos

WTC2 South Tower, Molten Metal pouring out the North-East Corner

Pouring molten aluminum into a pool

Molten aluminum into cold water

Evidence of fused molten metal and concrete of extreme heat.

Thermite cutting steel - Validated experimentally

The fact that the rubble contained steel or iron that had been melted shows that the buildings were destroyed by something other than fire and airplane impact.

When all of this physical evidence is combined with the testimony about explosions from many types of professionals, the claim that the Twin Towers were brought down by nothing other than the airplane impacts and resulting fires is simply not credible

Mentioned_Videos · 3時間前

Videos in this thread:

Watch Playlist ▶

VIDEO	COMMENT
(1) David Topete, MSCE, S.E. (2) Kamal Obeid, C.E., S.E. -- Civil and Structural Engineer - AE911Truth.org (3) WTC7: NIST Finally Admits Freefall (Part I) (4) WTC7: NIST Finally Admits Freefall (Part II) (5) WTC7: NIST Finally Admits Freefall (Part III)	12 - Hello all, Dr. Robert Korol, professor emeritus of civil engineering at McMaster University in Hamilton, Ontario, and a fellow of the Canadian Society for Civil Engineering, has led a team of academic researchers in preparing two peer-reviewed scien...
(1) Firefighter Describes Molten Metal at Ground Zero, like a Foundry (2) COLLATERAL DAMAGES (Part 1 of 5) (3) Les Robertson Confirms Molten Metal in WTC Basement (4) WTC2 South Tower on 9/11 Molten Metal North-East Corner (5) Pouring molten aluminum into a pool!! (6) Molten aluminum into cold water (7) 9/11 WTC Meteorites Molten Iron Concrete (8) 911 - THERMITE CUTTING STEEL VALIDATED EXPERIMENTALLY DEMON es1 of s1STRATED	1 - Jet fuel can't melt steel beams, so why was there molten metal at the WTC collapse sites? NIST claims that WTC 1&2 collapsed due to jet fueled fires (just normal offices fires for WTC7) which were not hot enough to produce molten steel or iron, ...
(1) Guinness world record: The tallest domino structure on earth: 10.05 meter (32.9 feet) (2) NMSR does the Heiwa Challenge (3) Offset narrow core progressive collapse (4) Blender Demolition - Case Study: World Trade Center (Demo 3) (5) Gravitational Collapse onto Cumulative Supports (6) Acceleration + Serendipity / David Chandler	1 - On behalf of /r/towerchallenge: thank you! The Tower Challenge was created to fill the information vacuum between "only inside job" /r/911truth, where defense of the "official explanation" is frowned upon as "off topic"...
(1) WTC 7 Collapse - all angles HD 720p Compilation (2) ENHANCED VERSION: News Reports WTC7 Fell Before It Happens!	1 - The official government conspiracy theory regarding 9/11 and especially the NIST report NCSTAR1A, Final Report on the Collapse of World Trade Center Building 7, is scientifically impossible. WTC 7 went into free-fall (click for a compilation), lite...
(1) Fraud Exposed in NIST WTC 7 Reports (2) 4 WTC7 Part 3 Investigation That Ignored the Facts - ESO - Experts Speak Out (3) 13 WTC TT Part 4 Eyewitness Reports of Explosions - ESO - Experts Speak Out (4) 17 Ground Zero Part 3 High Tech Incendiaries in WTC Dust - ESO - Experts Speak Out	1 - Seven provable points which clearly demonstrate that the report produced by the National Institute of Standards and Technology (NIST) on the destruction of WTC7 was unscientific and fraudulent. WTC7 (1) omission of girder stiffeners shown on franke...

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Greg_Roberts_0985 · 3時間前

Using conservation-of-energy analysis to perform a simple, basic physics check that establishes WTC1,2&7 were controlled demolition.

Gravity

Mankind has learned that the force of gravity comes from an acceleration of known constant magnitude, depending only upon mass and separation - gravity has always had the same, predictable, effect.

So while an object of greater mass will exert more force upon anything which is supporting it against gravity's pull (ie, it's heavier), it does not experience any greater acceleration when gravity's pull is not opposed (ie, when it's falling). Earth's gravity can only accelerate objects downward at one known, constant, maximum rate (1 g). Heavier objects are not accelerated any quicker than are lighter objects, as Galileo demonstrated centuries ago.

Basic Physics

Earth's gravity will produce a downward acceleration of 32 feet per second per second.

What that means is that an object

after falling one second, will be falling at 32 ft/sec.
After the 2nd second, it will be falling at 64 ft/sec.
After the 3rd second, it will be falling at 96 ft/sec.

And so on.

This can easily be explained via numbers and arithmetic

Velocity = Gravity x Time

and

Distance = 1/2 x Gravity x Time(squared)

So if we want to know how far the object has free-fallen after 3 seconds:

Distance = 1/2 x 32 x 9 = 144 feet

So after 3 seconds, in Earth's gravity, an object will have fallen 144 feet and will be falling at 96 ft/sec.

Kinetic Energy and Potential Energy

In the case of a free-falling body, the two kinds of energy we are concerned with are kinetic energy and potential energy.

As an object falls, it gives up potential energy for kinetic energy, the equation for potential energy is...

Potential Energy = Mass x Gravity x Height

The equation for kinetic energy is as follows:

Kinetic Energy = 1/2 x Mass x Velocity(squared)

So let's just say, for the sake of simplicity, that our falling object has a mass of 1. (an object's mass will affect its energy, and its momentum, but not its rate of free-fall.)

The potential energy given up by falling 3 seconds

   (144 ft) is 1 x 32 x 144 = 4608

The kinetic energy gained after falling 3 secs is

   1/2 x 1 x 96(squared) = 1/2 x 9216 = 4608

So, all of the available potential energy was converted to kinetic energy. Energy was, in fact, conserved, based upon the sound principle of conservation of energy.

Air resistance

The free-fall equations perfectly predict the behavior of falling bodies which encounter zero resistance, as in a vacuum.

Only when there is zero resistance can any falling object's potential energy be completely converted into kinetic energy. Anything which interferes with any falling object's downward progress will cause its acceleration to be reduced from the maximum gravitational acceleration of 32 feet per second per second, as some of gravity's potential energy is consumed doing work overcoming resistance.

That's why you may have heard the term "terminal velocity". The free-fall equations predict that a falling object's velocity will continue to increase, without limit. But in air, once a falling object reaches a certain speed, its propensity to fall will be matched by air's resistance to the fall. At that point the object will continue to fall, but its speed will no longer increase over time.

There is a maximum possible rate at which objects fall, and if any of gravity's potential energy is consumed doing anything other than accelerate the object downward, even just having to push air out of the way, there will be less energy available to accelerate the object downward, and so that object's downward acceleration will be diminished.

And if an object's downward acceleration is diminished, it will be going slower along the way, and thus it will take longer to fall a given distance.

Free-falling from WTC heights

The towers were 1350 and 1360 feet tall. So using basic free-fall equations, lets see how long it should take an object to free-fall from the towers' former height.

Distance = 1/2 x Gravity x Time(squared)

or

2 x Distance = Gravity x Time(squared)

Time(squared) = (2 x Distance) / Gravity

Time(squared) = 2710 / 32 = 84.7

Time = 9.2

A basic mathematical equation tells us that it will take 9.2 seconds to free-fall to the ground from the towers' former height.

Using a simpler equation, V = GT, we can see that in order to reach the ground in 9.2 seconds, the free-falling object's velocity must be about 295 ft/sec, which is just over 200 mph.

But that can only occur in a vacuum.

Since the WTC were in Earth's atmosphere, you might be able to imagine how much air resistance that represents. One simply can not believe that any of the WTC towers reached these speeds. For example, the commonly-accepted terminal velocity of a free-falling human is around 120 mph. The terminal velocity of a free-falling cat is around 60 mph.

Therefore, air resistance alone will make it take longer than 10 seconds for gravity to pull an object to the ground from the towers' former height.

On page 305 of the 9/11 Commission Report, we are told that the South Tower "collapsed" in 10 seconds, the exact quote:

At 9:58:59, the South Tower collapsed in ten seconds.

This simply can not be, that's close to the free-fall time in a vacuum, and an exceptionally rapid free-fall time through air even if the "collapse" time was twice as much.

The "collapse" proceeded "through" the lower stories of the tower. Those undamaged floors below the impact zone would have offered resistance that is thousands of times greater than air.

Air can't do that.

Can anyone possibly imagine the supposedly-undamaged lower floors getting out of the way of the upper floors as effortlessly as air would? Can anyone possibly imagine the lower stories slowing any kind of fall of the upper floors less than would, say, a parachute? (And what energy source could have reduced the height of [most of] the columns, top-down, at the same rate?)

What is certain, beyond any shadow of a doubt, is that the towers could not have collapsed gravitationally, through intact lower stories, as rapidly as was observed on 9/11.

Not even close!

Conclusions

In order for the tower to have "collapsed" gravitationally, in the observed duration, one or more of the following conditions must have been met:

The undamaged stories below the impact zone offered zero resistance to the collapse
The glass and concrete spontaneously disintegrated without any expenditure of energy
On 9/11, gravity was much stronger than gravity
On 9/11, energy was not conserved

However, none of these physics-violating conditions can be accounted for by the official government conspiracy theory of 9/11, nor by any of the subsequent analyses designed to prop up the official theory of 9/11.

The governments explanation for the WTC "collapses" fails the most basic conservation-of-energy reality check. Therefore the governments jet fueled office fires hypothesis is impossible, and thus absurd.

It is utterly impossible for a "gravitational collapse" to proceed so destructively through a path of such great resistance in anywhere near free-fall times, the only logical explanation is controlled demolition.

SovereignMan · 9時間前

Fraud Exposed in NIST WTC 7 Reports

As a mod for /r/911Truth, thank you and we appreciate the opportunity to present evidence in this sub.

focaliza · 5時間前

Peer-rewieved journal (European Jouranal of physics) published this article about 9/11.
Main conclusions: It bears repeating that fires have never caused the total collapse of a steel-framed high-rise before or since 9/11. Did we witness an unprecedented event three separate times on September 11, 2001? The NIST reports, which attempted to support that unlikely conclusion, fail to persuade a growing number of architects, engineers, and scientists. Instead, the evidence points overwhelmingly to the conclusion that all three buildings were destroyed by controlled demolition. Given the far-reaching implications, it is morally imperative that this hypothesis be the subject of a truly scientific and impartial investigation by responsible authorities.

http://www.europhysicsnews.org/articles/epn/pdf/2016/04/epn2016474p21.pdf

Greg_Roberts_0985 · 3時間前

The official government conspiracy theory regarding 9/11 and especially the NIST report NCSTAR1A, Final Report on the Collapse of World Trade Center Building 7, is scientifically impossible.

WTC 7 went into free-fall (click for a compilation), literally gravitational acceleration (the official reports even admit this) which is impossible in a steel framed building, there is nothing in science or engineering that would explain how every single supporting column would disappear within mere fractions of a second, the only explanation, within the realms of science and engineering, is explosives of some description, taking out the columns in a timed sequence, this is how every single steel framed building has collapsed

The NIST theory violates basic Newtonian physics, IF, you choose to believe the official report that fires caused the collapse, obviously it is impossible for a building to go into freefall in any other scenario, this explains why NIST refuse to release there data for independent validation, the only relevant documents that support their theory that fire brought down a steel framed building (first time in history, still to this day) are classified for public safety, they will not even release them to a licensed NYC architect in regards a FOIA request

The NIST report is not peer reviewed and if one takes a minute to see why they will not release their data, then simply look at the four simulations that NIST performed with their "global LS-DYNA model" None of the computer animations look anything like the actual observed collapse, the models and alleged simulations are not based in reality

Take a look

1 2 3 4 5 6 7

NIST’s investigation absolutely begins and ends in the realm of computer simulation, manipulating the numbers to try and achieve the observed conditions, which they couldn’t even do, regardless of this fact, a computer simulation does not constitute an explanation and computer modelling is, at best, only as good as the input it receives and NIST will not give us their numbers

They never even bothered to fully model the structure

And as far as the “withheld data due to national security” goes, until it is known and is in the public domain, it will be impossible for outsiders to know exactly what it supports, as it is right now, the NIST report can be considered a work of science fiction

Their findings cannot be replicated or falsified due to the withholding of data and so if anyone outside of NIST believes what they say, they believe it on pure faith.

Page 3 and the architect's appeal over the remaining 3370 files

The acceleration of gravity in New York City is 32.159 ft/s2. WTC7 had 2.25 seconds of literal freefall, this is equivalent to approximately 8 stories of fall in which the falling section of the building encountered zero resistance. The collapse was complete in 6.5 seconds. Free-fall time in a vacuum, from Building 7's roof is 5.96 seconds

For any object to fall at gravitational acceleration, there can be nothing below it that would tend to impede its progress or offer any resistance. If there is anything below it that would tend to impede its progress or offer any resistance, then not all of the potential energy of the object would be converted to motion and so would not be found falling at gravitational acceleration (where did every single structural supporting columns go, instantly, at the exact same time?)

There's no exception to that rule, those are the conditions that must exist for gravitational acceleration to occur for the entirety of the duration of the time it occurs, this is basic Newtonian physical principles.

You either agree with this very basic concept, or you need to start making a case for a new realm of science that has never been witnessed before.

Remember also that the BBC even reported that the building had collapsed 20minutes before it had, remarkable.

The fact that Building 7 underwent free-fall means that none of the building’s potential energy was used to crush the structure below it. All of its potential energy was converted directly into energy of motion (kinetic energy), leaving no energy to do anything else. Therefore, the lower section of the building could not have been crushed by the falling section. The destruction of at least 8 stories of the lower section of the building had to have been accomplished by other means to allow the upper section of the building to fall through it in free-fall.

NIST’s theory is that the failure of a single column near the east end of the building caused neighboring columns to fail in a progressive manner. This is contradicted by the observed simultaneous collapse across the entire width of the building, which fell with a level roofline. A progressive collapse mechanism would have led to a progression of failures, visible deformation of the building, and gradual, asymmetrical collapse. This is what NIST’s computer model shows, but it is not what was observed. What we observed was the sudden onset of free-fall across the entire width of the building, which can only be achieved by controlled demolition.

Greg_Roberts_0985 · 3時間前

How Researchers Have Accounted for the Evidence Regarding the Structural Behavior of WTC 7

	NIST: FIRE-INDUCED FAILURE	INDEPENDENT RESEARCHERS: CONTROLLED DEMOLITION
Sudden Symmetrical FreeFall	Attempt to deny the occurrence of free fall. Then acknowledge it but obscure its significance and provide no explanation	Acknowledge and interpret as evidence that explosives were used to remove all of the columns simultaneously
Structural Dismemberment into a Compact Debris Pile	Terminate computer model shortly after collapse initiation and provide no explanation for observed phenomena	Acknowledge and interpret as evidence that explosives dismembered the structure and deposited it into a compact debris pile
Eyewitness Accounts of Explosions	Deny the existence of audio recordings and eyewitness accounts of explosions	Acknowledge and interpret as evidence of explosives
Foreknowledge of Destruction	Provide a hypothesis that is incompatible with the high degree of confidence and precision with which the destruction of WTC 7 was anticipated	Acknowledge and interpret as evidence of foreknowledge that WTC 7 was going to be brought down

In conclusion, the hypothesis of controlled demolition readily, simply, and completely explains all of the evidence regarding the structural behavior of WTC 7 during its destruction.

It also explains the high degree of confidence and precision with which WTC 7’s destruction was anticipated.

Greg_Roberts_0985 · 4時間前

Seven provable points which clearly demonstrate that the report produced by the National Institute of Standards and Technology (NIST) on the destruction of WTC7 was unscientific and fraudulent.

WTC7

(1) omission of girder stiffeners shown on frankel drawing #9114

Frankel Shop Drawing #9114
Girder_A2001_Stiffeners_Plan_HL
Girder_A2001_Stiffeners_Elevation_HL
(2) omission of three lateral support beams on the 13th floor g3005 beam

Frankel Shop Drawing #3005
Frankel Shop Drawing #3007
Frankel Shop Drawing #9150 and Frankel Erection Drawing #E12/13
(3) wtc 7 collapse at free-fall acceleration is not explained

Physicist David Chandler’s analysis of the descent of WTC 7 in three parts, 1, 2 and 3
(4) videos of the collapse of wtc 7 betray nist’s computer model

Pertinent short clip from the documentary film 9/11: Explosive Evidence - Experts Speak Out
(5) claims of investigating controlled demolition without testing for explosive residues

Pertinent short clips from the documentary film, 9/11: Explosive Evidence - Experts Speak Out 1, 2 and 3
(6) changes of statements on composite beams and shear stud use between drafts
(7) refusing of foia requests

The NIST letter refusing to release calculations and analysis substantiating the walk-off failures at columns 79 and 81

hikikomori_forest · 6時間前

Well, this didn't take long to devolve into exactly what OP feared.

Akareyon · 3時間前

On behalf of /r/towerchallenge: thank you!

The Tower Challenge was created to fill the information vacuum between "only inside job" /r/911truth, where defense of the "official explanation" is frowned upon as "off topic", /r/conspiracy, where confusion among keyboard experts abounds, and the engineering subreddits, where any and all, even the most technical, discussion was/is "blacklisted". In a sense, it was meant as a service to the communities on both sides of the fence: to outsource the "moderation nightmare". Only /r/911truth, who, it seems, have had enough of the ubiquitous "hammer and glass table" analogy, have taken up the offer so far.

The challenge: working from the assumption that no explosives, demolition devices, steel-eating termites or space beams played a role in the demise of the Twin Towers, then - true to Richard Feynman's "If it disagrees with experiment, it is wrong" and Galileo's assertion that experiment is the arbitrator of competing hypotheses - the physical phenomenon should be replicable in experiment, or at least the principle of progressive top-down self-disassembly be demonstrable. In short: Build a tower, pick up the top 1/4th and drop it on the rest. Observe. Report. Repeat.

We have, impartially, collected the works of Z.P. Bazant, Frank Greening, Daigoro Isobe, Gregory Szuladzinski, Anthony Szamboti, Robert Korol and many others to provide a theoretical background of the mechanical and physical considerations.

Additionaly, it might just be the most comprehensive collection of experiments relating to the topic - among them the domino tower world record (which, although only in the order of magnitude of ~10 meters, takes longer to disintegrate than the 400+ meter Twin Towers), a demonstration of the "pancaking" or "zipper" effect (where the "floor slabs" fall off from a "core" that needs to remain standing up), and this year's first serious attempt at a demonstration of the underlying principle: Mick West's Metabunk.org model, which is essentially a wobbly 2.5-dimensional 12-floor bookshelf that is barely held together by neodynium magnets and just so manages to stay up and disassemble itself once the collapse is initiated, albeit at a noticeably smaller rate than the Twins, and with distinct "jolts" which were not observed during the collapse of the North Tower.

The historical value of the magnetic bookshelf must not be understated: it was the first experiment in 14 years since Professor Bazant circulated his purely theoretical "Simple Analysis", which was circulated only two days after September 11th, 2001.

Another service, to my knowledge unique to /r/towerchallenge, is a chronological collection of expert opinion before and after the collapses. From Charlie Thornton, John Skilling, and Frank deMartini to Eduardo Kausel, Richard Ebeltoft, Hyman Brown, G. Charles Clifton and Matthys Levi - from "a three hundred ton element crashing into a building that has been designed to carry thirteen thousand tons would probably not do anything to the major building" to "there is no way to deny the inevitability of progressive collapse driven by gravity alone"; from "jet fuel melted the steel beams" [sic!] to "a mixture of water from sprinkler systems and molten aluminum from melted aircraft hulls created explosions that led to the collapses".

And since computer animations and simulations have become the most valuable tool in the box for experimenters, engineers and researchers, we have also assembled all animations that purport to prove one thing or another. We make the distinction between "animation", where only the video is known, and "simulation", where all input data is open source and the simulation can be verified. To date, no simulation is known, but an honorable mention goes to Kai Kostack's now-famous "Blender Demolition" animation which shows what the collapses should have looked like had the towers indeed consisted of pre-fractured elements with predetermined breaking points, but only shows the initiation stage - not the progression stage.

Also, no animation of the whole collapse sequence is known to this day.

A personal note

For many years, I tried to form an educated, objective and intellectually honest opinion. I read the papers both by Bazant and the "Truth Movement" and couldn't make much of a rhyme of all the seemingly complicated formulas and considerations. I figured it cannot be that hard for professionals and academics to come to a minimal consensus, after all, this is, in the most abstract sense, the simplest form of Classical Mechanics and Newton's/Euler's Laws of Motion: mass m falling from height h to the ground in time t on a planet with a gravitational surface acceleration of g. F=ma.

However, both positions were completely irreconcilable - inevitability said these, impossibility said those, and neither moved a millimeter. I know now that "impossibility" is a bold claim, as both the domino tower and the magnetic bookshelf demonstrate - but the "inevitability" camp, on the other hand, repeatedly and independently insisted adamantly that energy and momentum are NOT conserved in a closed system. At least not for 400 meter steel skyscrapers. And not on Tuesdays.

And refused to provide an experiment, or even an energetic analogy. Avalanches? Require the snow to slide off sideways of the mountain that remains standing. Dominos, chain reactions, Rube Goldberg-machines? Need to be set up intentionally, and meticulously so the progression does not "jam". Hammers and glass tables? All the way down! Zeno's paradox of Achilles and the tortoise on stilts.

I waited for the FEMA report, which was full of silence on the collapse mechanics, and theorized a pancake effect. I waited for the NIST report, 14000 pages of treatment of everything related to the Twin Towers - and two little footnotes saying that for "brevity", the collapse sequence itself was not treated at all, since it was so obviously (/s) "inevitable" once conditions for initiation were met. Owrly? Years later, the NIST FAQ went online, distanced themselves from the pancake theory and replaced it with... more silence.

The lack of scientific curiosity demonstrated here was probably reason enough for some to jump aboard the demolition hypothesis, but I still hesitated. Until one day, I stumbled over this video. I replicated a different version of these experiments with the same results and suddenly came to a deeper understanding of the concepts of "force", "momentum" and "energy", most of which I had only rote learned when I needed them for school. With the help of many discussers on different internet forums, I refined that understanding, how and when to apply E[g]=mgh, E[k]=.5mv² and E[p]=.5kx² and such.

Physics teacher David Chandler finally brought matters to a head: for the top of the North Tower to accelerate at ~0.64g, the resistance of the structure can only be 0.36g. But the structure was evidently built with a Factor of Safety in mind (the South Tower hardly budged when the huge, heavy airplane hit it at ~600 mph), let us be conservative and say it was only 3. IOW, instead of providing a force three times greater than necessary to hold up its own weight, it exerted only little more than a third of it - roundabout 90% of the structural integrity had to vanish to facilitate the smooth, constant, jolt-less downwards acceleration of the roofline. Of course these simple numbers can now be integrated over space and time, to allow for "invisible micro-jolts", but this needs then be made up with even longer phases of almost-free fall - so the fact remains that, in the most abstract and objective, technical sense, vast amounts of energy had to be present in the Twin Towers which simply do not belong into a healthy, law-abiding office building.

These are only the ramblings of a ~~mad~~ layman, of course, so I can only invite all who are intellectually and academically interested in this debate, even if only for themselves and their own scientific integrity, to read 15 Years Later: On The Physics Of High-Rise Building Collapses by Steven Jones, Robert Korol, Anthony Szamboti and Ted Walter, which appeared in Europhysics News 47/4 and imho might, to date, be the most comprehensive and succinct case made for a serious and honest look at the collapse mechanics of the WTC Twin Towers and the free fall of the Salomon Building a.k.a. "WTC7".

The complaints of "conventional wisdom" scholars about the suggestibility and "intuition" of laypeople and their predisposition towards "woo", "conspiracy theories", superstition and right-out esoterics will fall forever on deaf ears if the trust lost in the scientific method as applied by academia in the last 15 years is not regained by intellectually honest, objective researchers who join the call for an independent and international investigation into the crimes comitted on and pursuing September 11th, 2001.

Again, thank you /u/raoulduke25, and thank you /r/engineering for your hospitality on the 15th anniversary of the greatest stage magic trick ever performed!

flyyyyyyyyy · 10時間前

For those interested in the actual demolition technique, here's how the buildings were demolished:

Ground Zero – Nuclear Demolition of the World Trade Center (archive)

and here's the canonical book that explains it in excruciating (1091 page) detail:

9/11thology: The “Third” Truth About 9/11 (ZIPped PDF)

and the same information in video/interview form:

Dimitri Khalezov: WTC Nuclear Demolition

here's an old wikipedia article describing the nuclear demolition technique generically, not specific to 9/11 - it was taken down after only a week:

Nuclear Demolition Theory: Censored Wikipedia Article

i suspect this comment will be radically downvoted or even deleted. this information is being heavily suppressed by the guilty parties and their pr agents. still, here's the information for those who can grab it before it disappears.

edit:

I should mention, the demolition company was almost certainly Controlled Demolition, Inc. (CDI) -- yes that's really their name. They are the current (known) world record holder, at 33 stories.

J.L. Hudsons Department Store - GUINNESS WORLD RECORD!! - Controlled Demolition, Inc.

and they got the 'clean-up' contract at both the WTC after 9/11 and the Alfred P. Murreah building in Oklahoma City. that's just too coincidental for my taste.

https://en.wikipedia.org/wiki/Controlled_Demolition%2C_Inc.#Select_Projects

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