9/11 WTC Debunking Resources

Mick West

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[WORK IN PROGRESS - add suggestions to the thread, and I'll incorporate them]

9/11 conspiracy theories are not going to go away, even though they have largely been debunked in quite some detail. There are always going to be people new to the theories who are simply no familiar with the rebuttals, or have rejected the rebuttals on spurious ground.

Debunking is not about picking a "side" of an argument, and trying to argue for that side. It's about identifying and exposing bunk in the evidence surrounding that argument. If, for example, someone claims that a 767 could not fly above 500 knots, then you'd need to explain how it can. Debunking is about these individual pieces of evidence.

The challenge to the debunker of 9/11 conspiracy theories is to find a way to communicate with the believer. Simply saying "you are wrong" is generally not going to work. Even explaining why they are wrong is probably not going to cut it. You really need to provide an alternate (genuine) explanation for something if you want them to actually realize they were wrong about something.

And pretty much all the ground has been covered already, in excruciating detail. There are many sites dedicated to 9/11 debunking, and it's interesting to think about why they fail. Here I'll list some of the more useful sites that can be most effectively used to understand various things that happened on 9/11. Many of these sites reference each other, and it's a bit messy. I'll try to structure this page better over time. Much as I don't want to start comprehensive 9/11 specific site, if I can't find a well structured list, I'll try to do something here. I'm really hoping though that I'll be able simply to boil things down to a short list of go-to sites.

I've added archive.is backups to the individual pages, and made local mirrors where possible.

911 Guide (http://archive.is/jcXn4) - One of the better structured sites - provides brief lists and descriptions of the various claims, with a brief explanation of the problems with the claims, and then links to more detailed discussions of those claims.

WTC7Lies (http://archive.is/2wncY) - An excellent site, but a bit unstructured, and with many broken links.

Debunking911.com (mirror)- a nice list of topics on the left, but articles are somewhat rambling and cover many points.

JREF Forum: Resources for debunking 9/11 Conspiracy Theories (http://archive.is/ywn01) - A useful, if rather unstructured collection of links

9/11 Myths, and the old site. Cover various things in depth and with good focus.

AE911Truth.info (https://web.archive.org/web/20170318050907/http://ae911truth.info/wordpress/) - focusses on the claims of Architects and Engineers for 9/11 Truth.

Popular Mechanics: Debunking the 9/11 Myths - Has a useful topic key at the bottom of the page for the major topics.

Debunking the 9/11 No-Planes Theory - Debunks the more fringe theory that no planes hit the WTC towers.

9/11 Pentagon Attack Review - Very detailed look at all the evidence around Flight 77 hitting the Pentagon.
 

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http://911-engineers.blogspot.ca/


This is a blog dedicated to all the engineers that have spoken out about what happend on 9/11 but were quotemined by the "truthmovement".
Content from External Source

Rather poor navigation, even if it does contain some useful info, it seems hard to find.

ETA: It's a lot better if you expand all the dates on the right. Pity they did not just make a big list of all the articles.
 
Can I start a thread on the topic of "squibs?" or puffs of concrete whatever you want to call it? You say these have been covered and it is "compressed air" what do you mean by compressed air? my argument is that these puffs or squibs prove that WTC was brought down using explosives.

If you can debunk something, then start a thread and debunk it. Just focus.

http://www.debunking911.com/overp.htm
Of course, I expect the conspiracy theorists to say this was just the explosives which caused the high wind ("He even says explosions!") but they have no evidence of explosives. We do have evidence of pancaking. The ejecta coming out of the windows of the pancaking floor was uniform across the floor and light in color. It was coming out of every floor window until the falling debris obscured its view. Controlled demolition has staggered ejecta because the charges are only on some columns. You also always see at least [some] before the collapse and not [only] during it. There are none of these jets of debris before collapse.
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http://www.nist.gov/el/disasterstudies/wtc/faqs_wtctowers.cfm

9. Weren't the puffs of smoke that were seen, as the collapse of each WTC tower starts, evidence of controlled demolition explosions?

No. As stated in Section 6.14.4 of NIST NCSTAR 1, the falling mass of the building compressed the air ahead of it—much like the action of a piston—forcing smoke and debris out the windows as the stories below failed sequentially.

These puffs were observed at many locations as the towers collapsed. In all cases, they had the appearance of jets of gas being pushed from the building through windows or between columns on the mechanical floors. Such jets are expected since the air inside the building is compressed as the tower falls and must flow somewhere as the pressure builds. It is significant that similar “puffs” were observed numerous times on the fire floors in both towers prior to their collapses, perhaps due to falling walls or portions of a floor. Puffs from WTC 1 were even observed when WTC 2 was struck by the aircraft. These observations confirm that even minor overpressures were transmitted through the towers and forced smoke and debris from the building.
Content from External Source

6.14.4 Events Following Collapse Initiation

Failure of the south wall in WTC 1 and east wall in WTC 2 caused the portion of the building above to tilt in the direction of the failed wall. The tilting was accompanied by a downward movement. The story immediately below the stories in which the columns failed was not able to arrest this initial movement as evidenced by videos from several vantage points.

The structure below the level of collapse initiation offered minimal resistance to the falling building mass at and above the impact zone. The potential energy released by the downward movement of the large building mass far exceeded the capacity of the intact structure below to absorb that through energy of deformation.

Since the stories below the level of collapse initiation provided little resistance to the tremendous energy released by the falling building mass, the building section above came down essentially in free fall, as seen in videos. As the stories below sequentially failed, the falling mass increased, further increasing the demand on the floors below, which were unable to arrest the moving mass.

The falling mass of the building compressed the air ahead of it, much like the action of a piston, forcing material, such as smoke and debris, out the windows as seen in several videos.

NIST found no corroborating evidence for alternative hypotheses suggesting that the WTC towers were brought down by controlled demolition using explosives planted prior to September 11, 2001. NIST also did not find any evidence that missiles were fired at or hit the towers. Instead, photographs and videos from several angles clearly show that the collapse initiated at the fire and impact floors and that the collapse progressed from the initiating floors downward, until the dust clouds obscured the view.

Content from External Source
And please read through these threads:
http://www.internationalskeptics.com/forums/tags.php?tag=squibs
 
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If ice can do that to an airplane, can you imagine what a whole building can do?
Yes. Shatter it into fragments.



Isn't the question "What can a fast airplane do to a building?"

The energy involved (KE) = 0.5*M*V^2, where M = 180,000 Kg (the weight of a Boeing 767-300ER) and V = 250 m/sec, and is therefore 563 billion Joules, or equivalent to 1.35 tons of TNT.

You have to imagine that NONE of that energy goes anywhere else (because it cannot). Now imagine.
 
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Isn't the question "What can a fast airplane do to a building?"

The problem is that both ways are disputed by CTers.

- Why didn't the strong airplane "bounced"?
- Why did the weak airplane damage the building?

My picture (together with hundreds of other examples) shows that the airplane is weak. What my be difficult to explain is that both structures are very strong, and when two strong structures collide, both will sustain damage.

If you send the WTC flying at 500 MPH into a hailstorm, the damage will be similar. ;-)
 
If ice can do that to an airplane

Yes....but a radome (IN the sense of commercial airliners) is not constructed of aluminium. It is a composite of various materials that are 'transparent' to radio signals...or "RADAR").

THIS because the weather-radar antenna apparatus is housed, there. The REST of the airplane (in reference to the events of '9-11') HAD a huge amount of mass, and energy.....

MASS 'plus' VELOCITY = 'ENERGY'.

(I might not be "understood" here....but think of a "missile".....HIGH ENERGY, with explosives on-board. Of course, the only "explosives" available on a commercial airliner were the Jet-Fuel....).

Too late to include....but? The term in the first sentence that referenced "RADAR" is something that, perhaps, not everyone knows about. HERE is a link to be looked at, for further understanding (There are more, of course):

http://en.wikipedia.org/wiki/Radar

I WOULD also like to add....in reference to the above? The development of RADAR dates back to WW2:

http://en.wikipedia.org/wiki/Radar#History
 
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What may be difficult to explain is that both structures are very strong, and when two strong structures collide, both will sustain damage.

MASS 'plus' VELOCITY = 'ENERGY'.

I had previously written (KE) = 0.5*M*V^2.

The V squared has enormous implications. It is why depleted uranium flechettes need no explosives.

The energy of the impact must have been shared equally by both plane and tower, and with 5/16" thick sheet steel box sections and four inch floors to fight, the aircraft lost the battle. Initially at least.

Someone, maybe here, has calculated the KE lost as the plane entered as 2.5% of the total.

I think that signifies easy entry without any risk of bouncing off.
 
The V squared has enormous implications. It is why depleted uranium flechettes need no explosives.

I think this needs to be further explained, to the "on-line audience".

To use the term "depleted uranium flechettes"? Most readers might not understand (and I KNOW!!!! I write stuff here, and forget that there is a VERY large audience of readers who aren't cognizant of the technical points or scientific specifics!! ....OF what I type!).

From what I understand...."depleted uranium", or "DU" is a VERY dense metal....after it is no longer radioactive (or maybe it still is??) BUT is a VERY effective, high-density metal to use at the tip of a warhead (or missile)? Am I close to the truth, here??

(ETA? Actually....just went to google....Here:
http://en.wikipedia.org/wiki/Depleted_uranium)
 
The problem is that both ways are disputed by CTers.

- Why didn't the strong airplane "bounced"?
- Why did the weak airplane damage the building?

My picture (together with hundreds of other examples) shows that the airplane is weak. What my be difficult to explain is that both structures are very strong, and when two strong structures collide, both will sustain damage.

If you send the WTC flying at 500 MPH into a hailstorm, the damage will be similar. ;-)
What that picture fails to illustrate is what happened to the hailstones. They of course were shattered into dust or even melted by the energy of impact. Both radome and hailstone "lost".

What it does illustrate well is that only those areas actually contacting anything will suffer damage. Now Note that most of the exterior wall of the towers are windows.
Energy goes into the columns that get hit. A first order calc then would be to note the mass of aircraft, aluminum, fuel, possible engine and wheel assemblies, etc., through a section of the aircraft in line with a column. A column of x width then will be impacted by a mass of aircraft through a x wide section of the plane. If the energy contained in that section is greater than the energy required to snap the column then the column will snap.

Think of a bullet, soft lead, traveling at mach 1 or so. It contacts a hard steel plate and contains enough energy to punch right through it creating a hole the same as the cross section area of the bullet. If the steel were a rod of less width than that of the bullet then the rod would be snapped through and the bullet would become two, or more, separate pieces. Would anyone expect the pieces of that bullet to be robbed of all forward velocity by being cut in half on contact with that rod?

Back to aircraft. Now we note that the contact with columns is tearing the plane into pieces. Those parts that hit glass we can treat as if they lose next to no momentum and enter the building at similar velocity as they were a split second before contact. The parts that hit column, if they contain enough energy to punch through a column, will continue into the building with a velocity that is dependant upon whatever energy was in excess of what was required to snap through the column.

THE ONLY pieces that will, or can, simply stop at the perimeter, are those that have less energy than required to snap through a column. Same goes for that bullet I wrote of. Slow it down and it will mash on the steel plate, maybe dimple it. Slow it down sufficiently and hit a steel rod and the bullet will mash against the rod too.
 
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Note that CT's often speciously describe a jetliner as a hollow thinly sheeted, aluminum tube. That's extremely inaccurate of course. It weighs 100+ tons so of course the first thing to note is that the wheels and wheel assemblies must be able to support that weight. Of course it has to land so it had better be able to withstand vertical and horizontal forces involved in decelerating that mass as well. Second, the engines must be made of materials strong enough to withstand the forces involved in accelerating that mass from zero to take off velocity in a few seconds. At that point the wings must be constructed strongly enough to also support the entire weight of the aircraft and forces generated in changing its altitude and direction. What of that actually 'tube'? Well, it must be strong enough to support you and around 100 other people, your luggage, the seats you sit in, the hydraulic machinery etc.

Sure its a thin aluminum tube.:rolleyes:
 
MANY years ago I read an article in a science-based periodical (Modern Science, Popular Science, Scientific American, etc. but I don't remember exactly which one) which went into great detail (more so than the Popular Mechanics article) regarding, rather specifically, how the physical construction of the WTC actually aided in it's collapse.. It described WTC 1 & 2 as (internally) resembling a box of Saltine crackers, basically an outer shell containing 4, separate, internal "stacks" of floors with the individual crackers representing the floors themselves.. Those floors, it said, were attached to both the outer shell & the central (steel) columns with L-shaped ALUMINIUM brackets (melt point @ 1221 Fahrenheit).. And it was the heat-softening, and subsequent failure, of these brackets which caused the pancaking effect.. Perhaps someone with better web-search skills than I could find this article and link it here..
 
...Those floors, it said, were attached to both the outer shell & the central (steel) columns with L-shaped ALUMINIUM brackets (melt point @ 1221 Fahrenheit).. And it was the heat-softening, and subsequent failure, of these brackets which caused the pancaking effect.. Perhaps someone with better web-search skills than I could find this article and link it here..
This is not true, the floor joist seats were STEEL welded to the perimeter and and core structures.
I doubt that a decently researched documentary would make such a claim and suspect that you perhaps misremember. If it did, then it's not a good resource.
I have no idea what article you are refering to, but I like the idea of floors as crackers.
 
Is this site for debunking 911 only? . . . in that you are only interested in articles or facts that help do that? For example, if something were to jar your thinking so that you began to see some truth in the fact that the buildings might have been demolished, would those facts be allowed here?
 
Is this site for debunking 911 only? . . . in that you are only interested in articles or facts that help do that? For example, if something were to jar your thinking so that you began to see some truth in the fact that the buildings might have been demolished, would those facts be allowed here?
please read the posting guidelines.

Metabunk debunks bunk. We dont care where the bunk comes from. Bunk is bunk.

as far as your question, which is off topic, you can start a new thread any time you would like. Following the posting guidelines. At Metabunk we examine specific claims of evidence. Conjecture, speculations or threads that try to argue a point simply by "this doesnt look right to me" claims, will be thrown into Rambles. Evidence of the claim must be provided.

If you have evidence of a specific claim you may start a new thread.

https://www.metabunk.org/posting-guidelines.t2064/

https://www.metabunk.org/metabunks-no-click-policy.t5158/

https://www.metabunk.org/threads/politeness-policy.1224/
 
Slide #7... really good stuff!
You need to manage your "Conflict of Interest" ;)
More seriously - I'm sorry that high profilers from those earlier days esp R Mackey are not around to bring their understanding up to date. Some aspects - like the causal attribution to tilt - are not strictly accurate. However very few would pick the blemishes. He is still way ahead of current Szamboti who hasn't moved at all IMO but....
 
some help here pls, is this Bld 7 or wtc 1 or 2 ? all my picture searches leave me unsure

I getting a headache trying to find work just where & when this is \

Thanks in advance D

famous-images-from-september-11-terrorist-attacks-03.jpg

famous-images-from-september-11-terrorist-attacks-04.jpg
 
some help here pls, is this Bld 7 or wtc 1 or 2 ? all my picture searches leave me unsure

I getting a headache trying to find work just where & when this is \

Thanks in advance D

famous-images-from-september-11-terrorist-attacks-03.jpg

famous-images-from-september-11-terrorist-attacks-04.jpg
I think less likely WTC 1/2 as I do not recall they ever having heavy fire at near ground level. The area is also littered with papers which suggests after at least one tower has fallen. Given the relatively relaxed onlookers, I would think its between 1 and 2 collapsing.
Frankly, looks more like #5, maybe #3, not sure from what direction though.
 

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my headache soothed thanks to all:), bld 5 or 6 explains why i had no seen or recognized it prior as not much mentioned about these.
 
Just thought I'd post this video which includes footage of WTC 7's south face as the face is being hit with debris, as well as it's side and top. Pretty interesting and not sure many have seen this.

I attached a small gif of the particularly rare shot.

 

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I once saw somewhere two other studies that were done on building 7 that are not the NIST report. There were links to them and I read some of one of them. Now I can't find these anywhere. Anyone know of these studies and possibly have the links? Thanks!
 
You can find the expert reports prepared by the plaintiffs in the Aegis Insurance litigation here, and you can find a report prepared by the defendants' expert witnesses here. The latter was never filed with the court for procedural reasons but has been independently republished by its principal author.

There are also at least two textbooks on disproportionate collapse that I've come across that discuss the collapse of World Trade Center 7 at length. You can find them here and here.
 
Yes. Shatter it into fragments.



Isn't the question "What can a fast airplane do to a building?"

The energy involved (KE) = 0.5*M*V^2, where M = 180,000 Kg (the weight of a Boeing 767-300ER) and V = 250 m/sec, and is therefore 563 billion Joules, or equivalent to 1.35 tons of TNT.

You have to imagine that NONE of that energy goes anywhere else (because it cannot). Now imagine.

only just woken up, but i think your figure of 1.35 tons of t.n.t. is out by a factor of at least 100.

1 ton t.n.t.= about 4,000,000,000 joules, cant find my calculator but around 135 tons of t.n.t.
 
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only just woken up, but i think your figure of 1.35 tons of t.n.t. is out by a factor of at least 100.

1 ton t.n.t.= about 4,000,000,000 joules, cant find my calculator but around 135 tons of t.n.t.
Weight and speed of the plane was overestimated. Here is my take on UA175 from years ago:
http://oystein-issues.blogspot.com/2010/09/kinetic-energy-of-flight-175.html

I used 116,000 kg instead of 180,000 kg, and 243 m/s instead of 250 m/s. AA11 was slower.

I find 3.42 * 10^9 J = 3420 MJ

One kg of TNT is 4.18 MJ - I thus get 3420 MJ / (4.18 MJ/kg) = 818 kg of TNT. Less than a ton.


For AA11:
http://oystein-issues.blogspot.com/2010/09/kinetic-energy-of-flight-11.html

120,660 kg and 208 m/s -> 2610 MJ -> 624 kg of TNT
 
Weight and speed of the plane was overestimated. Here is my take on UA175 from years ago:
http://oystein-issues.blogspot.com/2010/09/kinetic-energy-of-flight-175.html

I used 116,000 kg instead of 180,000 kg, and 243 m/s instead of 250 m/s. AA11 was slower.

I find 3.42 * 10^9 J = 3420 MJ

One kg of TNT is 4.18 MJ - I thus get 3420 MJ / (4.18 MJ/kg) = 818 kg of TNT. Less than a ton.


For AA11:
http://oystein-issues.blogspot.com/2010/09/kinetic-energy-of-flight-11.html

120,660 kg and 208 m/s -> 2610 MJ -> 624 kg of TNT
thanks, i used jazzies 563 billion joules , wildly out, but he got the 1.3 tons right, according to his weight and speed.
 
Reportage of Czech TV from controlled scientific fire of office building - talks with scientists, especially with Frantisek Wald, world leading expert for fire protection of steel buildings

9 min reportage in czech language and after it google translate. Frantisek Wald did opposition work of investigation of the fall of WTC buildings by NIST.
Czech TV Reportage from controlled experimental fire of office building

Frantisek Wald Google Scholar profile

Perex of reportage in "google translate english":
"Today, September 15, 2011 in Veselí nad Lužnicí burned. Burned not deliberately - experts demonstrated experimental fire buildings. The main impact has been verified by the security features of the fire-fighting construction of office buildings. František Wald from the Czech Technical University in Prague together with his doctoral student designed to withstand a large fire after more than one night. Similar experiments are extremely important, reliable assessment, not theoretical models “fit” on reality and that affect building standards and safety of new buildings. Attempts to immediately attack the WTC 7 buildings on 11 September 2001 following the terrorist attacks in New York. The mysterious fall is likely to have a fire on the building that affects the strength of the load-bearing structure differently than expected."

London, 1990. Before opening the office building
Broadgate broke out a gigantic fire that changed the view of the structures.

Prof. Ing. Wald František, CSc., Department of Steel and Timber Structures, Faculty of Civil Engineering, Czech Technical University in Prague: It has significantly contributed to increasing fire resistance worldwide.

Something that no one expected in Broadgate happened: the elements of the structure behaved differently in the fire than in the test rooms.

Ing. Tomáš Jána, Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: We can verify the load-bearing capacity and mechanical behavior of individual elements. This means that we take one beam, place it in the furnace, heat it with flame. Such a beam can be loaded and read its deflection, temperature, etc. All this is quite easy, but the building structure is always composed of a large number of such elements and can only verify the behavior of the structure as a whole during such fire tests on real objects.

On September 11, 2001, a new impetus was also given to the tests. After the collapse of the World Trade Center buildings 1 and 2, building 7 also collapsed. The analyzes soon clarified the fall of the twins, but the reason for the collapse of the Seven still remained a mystery. Several years of testing eventually showed that the cause was the failure of beam connections after a seven-hour fire that traveled through the building, fueled by diesel backup generators.

Prof. Ing. Wald František, CSc., Department of Steel and Timber Structures, Faculty of Civil Engineering, Czech Technical University in Prague: The traveling fire as a phenomenon was not studied until September 11th.

Real tests of fire performance of buildings are extremely costly and therefore only one or two are held annually worldwide. It would seem that they are unnecessary in the era of supercomputers, but new bold designs are being proposed and it is necessary to verify how they behave in reality.

Ing. Eva Dvořáková, Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: No matter how sophisticated the computational methods are, they never give us information about the actual state. But experiments will always show us the way it will actually behave.

In the Czech Republic, scientists conducted such an experiment in 2008 in Mokrsko. After a three-year pause, the experiment returned to the Czech Republic this year - in the fire test room in Veselí nad Lužnicí.

Ing. Kamila Horová, Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: It is an experimental building, but it is a type of administrative building. It should be the most used type. True, what is there tested some elements, connections. They have already been tested, they are common. There are some innovations that are not widely used in our country.

It was a great event for the scientific community. People from almost all over the world came to watch the building's behavior during the experiment. There were about four hundred in Veselí. Unlike the one-storey building in Mokrsko, scientists built two floors in Veselí, carrying out an experiment with a traveling fire in the upper one. It has a different effect on the building than a space fire, when everything ignites at once.

Prof. Ing. Wald František, CSc., Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: The most famous for traveling fires - for application and, unfortunately, also for verification in practice - are oil production platforms. These are the largest steel structures of today. We are preparing further knowledge also for common office and residential buildings.

It turned out that the computer model estimated the highest temperature quite accurately. The forecast was 830 ° C and actually reached only 30 degrees higher. It was worse with the time estimate. The computer set the highest temperature at thirty minutes, but it was five minutes ahead of it.

Ing. Eva Dvořáková, Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: I would say that if the results differ by more than five minutes, we could say that the modeling is not quite accurate. Therefore, we will try to create our own model based on this test, which should be more accurate.

The aim of the test on the lower floor should be the effect of a spatial fire on the construction of a normal office building. The ceiling slab is therefore loaded with gravel bags, which simulates the normal payload, ie floors, partitions and furniture. Computers will continuously record the temperature in the sensors.

It is the afternoon of September 15, 2011. Firefighters inside ignite the boundaries of carefully dried pine wood. If a building collapses like a Mokr in a fire, detailed records will be available.

Ing. Václav Smítka, Department of Special Geodesy, Faculty of Civil Engineering, CTU in Prague: Every five minutes the scanner starts from the beginning and scans the lower floor of the burning object. Laser scanning is a method of contactless determination of coordinates. Using this method, we perform a dynamic deformation test of the building envelope.

The temperature rose very quickly inside the building. The ceiling beams softened and began to deform. At about fifty minutes, a strange sound frightened everyone.

Prof. Ing. Wald František, CSc., Department of Steel and Wood construction, Faculty of Civil Engineering CTU in Prague: Exploded steel-concrete column. In fact, the concrete contains about fifty percent of the free water, which expands when heated to 900 ° C. The pressures can be so great that the steel shell of the column breaks. However, the supporting function and thus the whole structure should not be affected.

This was also confirmed. The building was slightly shaken by the explosion and the beams continued to sag.

Ing. Pavel Zíma, Center of Experimental Mechanics, Institute of Theoretical and Applied Mechanics AS CR: Deflection increased to 78 cm in the middle and on the edge where there are two columns, there is a 45 cm deflection.

The maximum deflection eventually was 82 centimeters. This in the section with the highest temperatures. The concrete slab cracked and the crack along the rear wall of the building grew to a few meters.

Prof. Ing. Wald František, CSc., Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: Well, the crack is big, but how big it is, we will know it tomorrow when we can enter.

The researchers obtained so much data during the test that their processing will continue for the next year. However, the first results are known about two months after the test.

Ing. Tomáš Jána, Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: For example, we have verified that if we protect at least a part of a steel-concrete structure against fire, for example construction.

Where the beam was supported by a column, scientists provided fire protection with a length of only 50 cm. This was enough to ensure that the connection did not exceed 350 ° C during the entire fire, while the unprotected center of the beam was heated to 950 ° C.

Ing. Tomáš Jána, Department of Steel and Timber Structures, Faculty of Civil Engineering, CTU in Prague: If we did not protect the connections, the beam would theoretically withstand the entire course of the fire, but the connections could break. In this way, we only protect the weakest link in the structure and thus increase the overall fire resistance.

In the summer of next year, scientists will complete instructions on how to design new steel-concrete structures resistant to fire, explosion and earthquake. If everything goes well, the results will be used worldwide in two years.

Prof. Ing. Wald František, CSc., Department of Steel and Timber Structures, Faculty of Civil Engineering CTU in Prague: There are relatively few such administrative buildings in the Czech Republic. The boom in the construction of such objects is currently in China and Southeast Asia. That is why it is most evident there.

Ing. Eva Dvořáková, Department of Steel and Timber Structures, Faculty of Civil Engineering, Czech Technical University in Prague: Every experiment that is currently under way focuses on something new. It is nothing that repeats itself, which is a waste of time. So what we do here is a new thing that is not yet covered by standards.

In Europe alone, 2.5 million fires occur every year. Thousands of people will lose their lives. If only some of them save the experiment in Veselí nad Lužnicí in the future, then this effort made sense.
 
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