Moderated Continuation - Why a one-way Crush down is not possible

[dtugg]

I wonder if you meant to say 're-education camps' or 'reduction camps '

Could that be a Freudian slip or should we be thinking along the lines of soap,candle and lampshade factories ?

You'll see soon enough.

 

[tfk]

Tony,

It sounds like you don't think it would take too much time to build a complete representation of the central core.

.
No, having done it a couple hundred times with far, far simpler structures (machined assemblies, not buidings), I accept that the task is enormous. However, once you get one floor complete, duplicating it 110 times is no more difficult - for you - than duplicating it 2x.

For the computer that has to crunch that number of DOF model, however, it's a completely different story...

Of course, what you've given me is one (fairly poor, frankly) REASON that your model is absurdly non-representative, and any conclusions drawn from it, completely unsupported.

When trying to help younger engineers mature, I've always tried to impress upon them that the goal of their work is NOT to have good, better or even superb reasons that their conclusions are meaningless.

Catch my drift...?
.

The columns in the central core were only unsupported for one story. That is what the interconnecting beams at every floor are about besides carrying floor loads.

.
Quite obviously true ... in the standing building.

Very little of the, uh, "interesting" discussions here relate to the "as standing" building. This is a recurring theme, Tony.

You guys keep quoting things like "design factor of safety". You DO realize that the numbers given for that apply ONLY to the complete, intact, undamaged building, don't you?

Let's say that you built a new, imaginary WTC1 tower in your mind. We'll allow the same events to proceed right up to the just past the moment of collapse initiation. The outer columns have failed, and the upper block has descended 1/2 story. Not yet impacted the floor below. And we stop time, remove the upper block & set it aside, etc., and examine the top of the remaining structure.

Why don't you use your imagination and give us a description of the condition of the top couple of stories of the lower segment.

Don't use JUST your imagination, tho. Go look at some slo-mo videos of the collapse starting. Make your model match what you see.

Rules:
Start With No Conclusions.
Open Your Eyes.
Look Carefully.
Try To Make Sense Of What You See. (Your model should help with this.)
Make Sure That None Of Your Conclusions Violate What You See.

Work your way carefully from the starting point
1. what you "know for sure" to be true (i.e., what you can see), to

The 1st tier:
2. the certain consequences of what you know for sure but can't see, to
3. the probable consequences of what you know for sure, to
4. the possible consequences of what you know for sure, to

the 2nd tier:
5. the certain consequences of 2. above
6. the probable consequences of 2. above
7. the possible consequences of 2. above, to

the 3rd tier
8. the certain consequences of 3. above, to
9. the probable consequences of 3. above, to
etc. etc. etc.

Return to Point 1 OFTEN as a sanity check on any of your conclusions.

Why don't you try that, and come back with a description of the various components in the top several stories (your analysis will tell you how many stories you have to consider) of the lower tower after the upper block has descended 1/2 story.

This will be MUCH more valuable to you than generating an FEA model of the tower.

Your principle task will be
1. to gain a much better feel for the destruction process, and
2. to figure out how many of the core columns are unsupported at this point, and for how many floors they are unsupported.

Tom

 

[funk de fino]

Why don't you ask the History Channel funk?

If you want to call me a liar that would make one out of you. You have no idea and are merely surmising that it couldn't be true that Silverstein made comments about WTC 7's collapse in more than one place. Well he did and he said it was a controlled demolition for safety reasons. I was not suspicious at the time and not until I read Steven Jones' paper a couple of years later did I ask myself when there would have been a chance to set the charges in WTC 7. At that point I called the History Channel to try and get a copy of that show. They told me it wasn't available to the public.

I would expect Mark Roberts to chime in here any time now. He tries to antagonize me with this too as it seems it is all he can do. Neither of you seem like you have much to contribute to the engineering side of this debate.

Your claim, your proof.


You are a bald faced liar Tony. There is no documentry where Silverstein used the "exact" words that it was a CD for safety reasons. If there was you could bring it. You are the only person in the whole wide world that makes this false claim.

What was the name of the documentary and when was it broadcast?

What were his exact words?

As for engineering. I am not the moron who is trying to claim the core could have stood on its own.

I am not the one who lied about what evidence NIST had and what they studied. I showed you were wrong on that too and I proved you had not read the NIST report fully.

Your credibility is shot, its over.

 

[tfk]

Tony,

The beam to column connections in the central core were not pinned connections. They were large connections with multiple bolts and welds which provided significant resistance to rotation of the column at the connection.

You keep saying they were pinned because that is a conservative method for design. That doesn't make it a reality.

.
Sorry, Tony. The evidence in the rubble says that they were, in fact, "pinned joints". The pin being - not at the bolts - but at the 90° formed radius in the bracket. This small piece of metal was completely incapable of resisting the torquing action of the cantilever floor as soon as the truss to peripheral column joint failed. That MAKES it a pinned joint. (One with a bit of friction to it. But only a TINY bit of friction.)
.

The columns in the core were considered compact shapes because they had an effective length factor of about 0.65 to 0.70 and were only unsupported for one story giving them a relatively low slenderness ratio. Those columns were not buckling until they got near yield, which would require 3 times the load they were carrying.

.
When considering the collapse, Tony, you should be looking at the core & peripheral columns at the 98th (or so) floor. What length factor are you describing here?

As soon as the building starts to "disassemble", how many floors are unsupported?

Tom

 

[FineWine]

The core columns were interconnected by pinned end beams. These do not form a lateral resisting system. Let's look at a basic engineering problem, structures 101 really:

There are two fixed based columns with a beam rigidly attached to the columns. A horizontal force is applied to the top of each column. The beam will develop large moments and act to connect the two columns. The horizontal force is resisted not only by bending in the columns, but also as overturning moment on the frame. One column now develops a tension force and another develops a compression force. For the laypeople: take a chair and push it from the top. The whole chair moves as a body and begins to tip over.

Now take the same problem and change the beam to pinned end connections. What is the force in the beam? ZERO. The horizontal force is completely resisted by bending through the columns and the only axial force in the columns is their own self-weight.

I already did the calculation showing that the core wasn't self-supporting. How? The core doesn't act together. Each column is completely laterally independent when the floor diaphragm and/or perimeter moment frames are removed. And a single column can't stand by itself, which is why the core fell over after the collapse.

This isn't a complicated subject. It's really rather basic engineering.



The shape you made up doesn't represent anything in reality and the equations you used don't apply to your made up shape if it did exist. You need to read up on compact vs. non-compact shapes.



This is completely irrelevant to the WTC.

I'm really not asking this question to be unkind to Tony Szamboti, but why doesn't he get it? I mean, engineers come in different shapes and sizes, but all of them have roughly the same background. I exclude Heiwa from this discussion, as he is either insane or willing to make himself appear crazy to advance his political agenda. I don't understand how making a fool of oneself is supposed to persuade anybody, but let's waste no more time on Heiwa. You and Tony clearly disagree. One of you is right and other is wrong (I and others on this forum who lack specific knowledge of engineering strongly suspect that it is you who are right). But wouldn't bridging the chasm separating the two of you require nothing more than good faith? How can error survive honest scrutiny? Heiwa can never admit to being wrong or be persuaded of anything because he is dishonest. Two scientists who disagree can always resolve their differences through frank discussion, or am I being too idealistic?

 

[Gamolon]

Your claim, your proof.


You are a bald faced liar Tony. There is no documentry where Silverstein used the "exact" words that it was a CD for safety reasons. If there was you could bring it. You are the only person in the whole wide world that makes this false claim.

What was the name of the documentary and when was it broadcast?

What were his exact words?

As for engineering. I am not the moron who is trying to claim the core could have stood on its own.

I am not the one who lied about what evidence NIST had and what they studied. I showed you were wrong on that too and I proved you had not read the NIST report fully.

Your credibility is shot, its over.

Not a very good track record Tony. Ever find the quote from Skilling saying that he and his people did analysis of the effects of fire on the steel structure of the towers?

 

[FineWine]

The core consists of 46 vertical columns interconnected by horizontal beams at regular intervals. This assembly of structural elements, connected to ground, is self-supporting and quite elastic.

You really don't see how illogical it is to talk about an assembly being self-supporting. An individual vertical column either is or is not self-supporting. If columns are interconnected by horizontal beams, it makes no sense to refer to them as self-supporting. They are part of an assembly, i.e., they are not supporting themselves.

You really, truly, honest-to-god, have no idea of what I'm saying.

 

[FineWine]

Yes, they got destroyed, but let's face it; The upper part (C), a weak structure, mostly air, cannot crush the lower part (A) due to local failures (plane impact, fire) and with C displacing down on A. The latter displacement will produce and apply too little energy - locally - and it would only produce some further local, structural failures in both parts where the energy/forces are applied. You cannot destroy a building by dropping a little part of it on the rest!

So what is the alternative cause of total destruction? In my view CD from top down is quite obvious as explained by David Chandler & Co. It is a pity that US authorities do not investigate that cause properly.

I will tell you again that there is no part A. The collapsing floors crush the floors below ONE-AT-A-TIME. When will you stop ducking this very obvious refutation of your madness? Do you think that nobody can see you run from it?

 

[tfk]

Tony,

You have no idea and are merely surmising that it couldn't be true that Silverstein made comments about WTC 7's collapse in more than one place.

.
This statement is so all-encompassing & generally true as to be useless, Tony. It applies to every person in the world, regarding every topic in the world.

What works as evidence is proof (i.e., video or verified audio) of what he DID say. Not what he COULD HAVE said.
.

Well he did and he said it was a controlled demolition for safety reasons...

.
THIS is a strong claim. A strong piece of evidence, if you can prove it, of course. So focus on this.
.

At that point I called the History Channel to try and get a copy of that show. They told me it wasn't available to the public.

.
Which show, what date. The History Channel has virtually all of its "high public interest" documentaries available for sale. $19.95 breaks open the "story of the century", Tony.

The reason that I am highly skeptical is all those YouTube videos of Rumsfeld saying "Flight 93 shot down ...", and GWB saying "... I saw the first plane fly into the building before going into the classroom in Florida...".

Both of these were clear misstatements on their parts. They were on TV news. And people had made recordings of those videos & have posted them. Do you think that it is even remotely possible that, with all the highly motivated truthers out there, NOT ONE of them bothered to tape the History Channel's presentation??

Do you think that it is remotely possible that, if Silverstein had said this, that truther would NOT have pulled it off of his TiVo & posted it to YouTube?
.

I was not suspicious at the time and not until I read Steven Jones' paper a couple of years later did I ask myself when there would have been a chance to set the charges in WTC 7.

.
You're an ME, right Tony? You've listened to Jones talk about ME type issues, right?

Give me, please, your HONEST impression of his grasp of general ME concepts.
How about his statement that "the 2nd law of thermo PROHIBITS the tower from falling straight down".
.

Neither of you seem like you have much to contribute to the engineering side of this debate.

.
I'll try to contribute to the engineering discussion, Tony. I promise.

Tom

 

[FineWine]

You mean the two utterly unique collapses happening within an hour of each other followed seven hours later by a third and completely different type of absolutely unique collapse ? All three modes of destruction being firsts in world history ?

I think we know enough Bad Boy.

This the latest exhibit in your cavalcade of lunacy? The collapses of the North and South towers were unique (well, to sane people, they are obviously unique in that they were the only two skyscrapers ever hit by commercial airliners), by which you mean they were different from each other?! Think hard, Bill, and tell me if you can't find the common denominator.

Hint: look inside the parentheses.

 

[FineWine]

Why don't you ask the History Channel funk?

If you want to call me a liar that would make one out of you. You have no idea and are merely surmising that it couldn't be true that Silverstein made comments about WTC 7's collapse in more than one place. Well he did and he said it was a controlled demolition for safety reasons. I was not suspicious at the time and not until I read Steven Jones' paper a couple of years later did I ask myself when there would have been a chance to set the charges in WTC 7. At that point I called the History Channel to try and get a copy of that show. They told me it wasn't available to the public.

I would expect Mark Roberts to chime in here any time now. He tries to antagonize me with this too as it seems it is all he can do. Neither of you seem like you have much to contribute to the engineering side of this debate.

You are obviously wrong about the Silverstein quote. You are the only "truther" to make this mad claim, and "truthers" behave like birds on a wire: when one takes off, the whole flock follows. It is inconceivable that you are the only member of your insane movement who is aware of this stunning, and plainly false, quote by Silverstein.

 

[BigAl]

Tony,


.
Sorry, Tony. The evidence in the rubble says that they were, in fact, "pinned joints". The pin being - not at the bolts - but at the 90° formed radius in the bracket. This small piece of metal was completely incapable of resisting the torquing action of the cantilever floor as soon as the truss to peripheral column joint failed. That MAKES it a pinned joint. (One with a bit of friction to it. But only a TINY bit of friction.)
.
Tom

I'm having problems visualizing that. Got an illustration handy ?

(Thanks for all the great explanations.)

 

[FineWine]

Of course not Bad Boy. When you can show any example of 10% of a structure crushing down the other stronger and fully intact 90% of the same structure to the ground by gravity alone then we will listen to you. You can choose any example from the entire world history of construction on this planet. We can't be much more generous than that.

Your movement is not generous; it is merely stupid and dishonest.

THIRTEEN COLLAPSING FLOORS HIT ONE FLOOR, THE FLOOR IMMEDIATELY BELOW, CRUSHING IT AND ADDING ITS MASS.

THE PROCESS IS REPEATED UNTIL THE BUILDING IS GONE.

You can run, but you can't hide.

 

[BigAl]

You mean the two utterly unique collapses happening within an hour of each other followed seven hours later by a third and completely different type of absolutely unique collapse ? All three modes of destruction being firsts in world history ?

Wrong. This wasn't the first time fire caused a steel building to collapse. Not by a long shot.

(sorry for the brokem HRML. This is a work in progress.)

January of 1997 -- the $15 million dollar Sight and Sound Theater in Lancaster
County, Pa collapsed due to fire. <br> <br>

http://www.interfire.org/res_file/pdf/Tr-097.pdf <br> <br>


Historical Survey of Multistory Building Collapses Due to Fire <br>
By: Jesse Beitel and Nestor Iwankiw, Ph.D., P.E. <br> <br>
http://www.fpemag.com/archives/article.asp?issue_id=27&i=153 <br>

On Jan 16, 1967, the steel roof of the McCormick Place in Chicago
collapsed due to fire <br> <br>



Enigma Business Park fire <br> <br>
http://www.bbc.co.uk/herefordandwor...s/2006/11/03/malvern_fire_video_feature.shtml
<br> <br>

Dutch fire <br> <br>
http://www.youtube.com/watch?v=ZaK5YVVaRCo
<br> <br>

------------ <br> <br>

September/October 2002 <br> <br>

Bridge Rebuilt on the Fast Track <br>
by Timothy Barkley and Gary Strasburg <br>

When a crash occurs on a main travel artery, it can back up traffic for
miles-causing a chain reaction affecting every route in the vicinity. If the
incident occurs at an interchange of three major highways and destroys a
well-traveled bridge, transportation officials have the makings of a major
congestion emergency. <br> <br>

This exact scenario occurred at the junction of Interstates 65, 20,and 59 in
downtown Birmingham, AL, on Saturday, January 5, 2002. At approximately 10 a.m., a
gasoline tanker truck hit the I-65 Southbound bridge. Fire and heat caused the steel
girders to sag up to 3 meters (10 feet) on one side. The interchange was engulfed in
smoke that filled the skyline, visible to motorists and residents of the city.
<br><br>

------------------------------------------------------------------- <br>

Steel building collapsses due to fire. <br><br>

http://www.charleston.net/news/2007/jun/20/mourning_heroes/ <br><br>

Mourning 9 heroes <br>
By Noah Haglund (Contact), Nadine Parks (Contact), Glenn Smith (Contact)
The Post and Courier <br>
Wednesday, June 20, 2007 <br><br>


'Fearless' Charleston firefighters 'will never be forgotten,' Riley says Capt. Ralph
Linderman of the St. Andrews Fire Department said the blaze was the hottest he could
recall in three decades of firefighting. "That fire bent steel like a wet noodle,"
he said. <br><br>

http://en.wikipedia.org/wiki/Charleston_Sofa_Super_Store_fire <br>
<br><br>
---------------- <br>

(04-29) 12:51 PDT -- A huge ball of fire from an exploding gasoline tanker melted
steel and caused an overpass in the MacArthur Maze near the East Bay end of the Bay
Bridge to collapse onto the roadway below early Sunday, virtually ensuring major
traffic problems for weeks to come. <br><br>

The tanker, loaded with 8,600 gallons of unleaded gasoline, was heading from a
refinery in Benicia to a gas station on Hegenberger Road, in Oakland, shortly
before 4 a.m. when it crashed. <br><br>

Engineers not connected to the incident said the steel underbelly of the I-580
overpass seems to have heated to a sufficient temperature to bend -- and that
movement pulled the roadbed off its supports. <br><br>

"It was so much engulfed in flames, it was hard to see the freeway itself,"
Rodriguez told KCBS radio. "It was scary because, you know, it's metal and
cement... You could see the freeway drooping. It looked like plastic melted. It was
unbelievable. It was bent and finally it just fell and we saw it hit the ground."
<br><br>


http://sfgate.com/cgi-bin/article.cgi?f=/chronicle/archive/2007/04/29/BAGVOPHQU46.DTL
<br><br>

------------------------------- <br><br>


1989 FIRE CLOSES I-78, FORCES DETOURS <br>
http://www.nycroads.com/roads/I-78_NJ/ <br>

FIRE CLOSES I-78, FORCES DETOURS: In the early morning hours of August 7, 1989, a
multiple-alarm fire at an illegal garbage dump underneath I-78 near Newark Airport
caused heavy damage to the freeway overpass. The source of the fire was a mound of
trash 25 feet tall and hundreds of yards long consisting of scrap wood, plastics
and paper. The heat of the fire buckled the ten-inch concrete surface and melted
steel support beams, and the resulting weight shifts from the highway (which had
sagged nearly a foot) <br><br>

 

[BigAl]

Of course not Bad Boy. When you can show any example of 10% of a structure crushing down the other stronger and fully intact 90% of the same structure to the ground by gravity alone then we will listen to you. You can choose any example from the entire world history of construction on this planet. We can't be much more generous than that.

You forgot the structural damage caused by the impact, the added, unplanned 150 tons of aircraft debris that exceeded floor loading limits and the fire caused by gas and the lack of a functional sprinkler system.

You and Heiwa always forget that stuff in his "models".

Henry Guthard, 70, one of Yamasaki's original partners who also worked as the project manager at the [WTC] site, said, "To hit the building, to disappear, to have pieces come out the other side, it was amazing the building stood. To defend against 5,000 (sic) gallons of ignited fuel in a building of 1350 feet is just not possible.

Report From Ground Zero
http://snurl.com/j54gc (Bottom of page 188)
​

 

[Newtons Bit]

The beam to column connections in the central core were not pinned connections. They were large connections with multiple bolts and welds which provided significant resistance to rotation of the column at the connection.

Go pick up a steel design book. The flanges of the beam have to be welded to the beam for it to be considered a rigid connection. Even shear tabs with multiple columns of bolts won't create a rigid connection: the beam and the column will not stay at 90 degrees under large amounts of load.

I've yet

You keep saying they were pinned because that is a conservative method for design. That doesn't make it a reality.

No. They're pinned because that's what they are. I've never said the beams were pinned because that's conservative for design.

The columns in the core were considered compact shapes because they had an effective length factor of about 0.65 to 0.70 and were only unsupported for one story giving them a relatively low slenderness ratio. Those columns were not buckling until they got near yield, which would require 3 times the load they were carrying.

Compact shapes have absoluetely nothing to do with slenderness ratios. It is not a function of length. It is a function of the depth of the cross-section to the thickness of the shape.

Furthermore, nothing in these structures can have an effective length factor of less than 1.0 EXCEPT the perimeter columns that had vertical braces (this would be at the mechanical floors).



K only goes down to 1.0 for moment frames. AISC is explicit about this fact.

 

[beachnut]

Beachnut, you don't ever produce calculations for anything. You have no idea and are obviously just spouting off what you want to think.

The 209 foot x 209 foot x 1368 foot tall building was self-supporting with much more weight than the core had on it. What makes you think a 137 foot x 87 foot x 1368 foot section could not be self-supporting? You have to calculate the moment of inertia to find out.

Although the core was not intended to take the lateral loads that doesn't mean it could not take any. I showed it could have taken a 40 mph wind and it was stable taking it's own weight vertically without external support.

Tony I was an engineer long before you became a failed delusion pusher and your work is a disaster. The missing jolt, the explosives used in the WTC are part of your failed opinions based on nothing but your biased view of the world. No body needs calculations to prove your conclusions are delusions. Your work is a waste of time and your conclusions on 911 are pure fantasy; ask an engineer not in your failed movement. I am an engineer so chalk up one engineer who knows your conclusion on 911 is poppycock. You have shown you are a conspiracy theorists with no evidence to support your ideas with failed engineering as a sideline.

I love your bragging of showing the core can take 40 mph wind when it needs to take much more if you had a clue about Wx. Next time show your source and the number of days with winds below 40 mph for the WTC. Source? Tony, even if your calculations are correct you just proved the core can't support itself laterally. You CTers always debunk yourself; try reality next time you pick something to expose with your "smoldering gun engineering".

 

[Heiwa]

Attack the argument not the poster is fine normally.

But Heiwa is an exception.

Mods, please ban him. He's just an idiot.

This IDtenT theory of yours is a little off topic. Here we discuss Why a one-way Crush down is not possible of any straucture, incl. WTC1, which I outlined in post #1 of the original thread. Please try to focus on that ... or show the opposite, i.e. that it is possible! If you can do the latter, you'll be a hero amongst some JREFers. It is very difficult, though. Impossible, actually

 

[BadBoy]

Your movement is not generous; it is merely stupid and dishonest.

THIRTEEN COLLAPSING FLOORS HIT ONE FLOOR, THE FLOOR IMMEDIATELY BELOW, CRUSHING IT AND ADDING ITS MASS.

THE PROCESS IS REPEATED UNTIL THE BUILDING IS GONE.

You can run, but you can't hide.

ever get the feeling your being ignored

 

[BigAl]

This IDtenT theory of yours is a little off topic. Here we discuss Why a one-way Crush down is not possible of any straucture, incl. WTC1, which I outlined in post #1 of the original thread. Please try to focus on that ... or show the opposite, i.e. that it is possible! If you can do the latter, you'll be a hero amongst some JREFers. It is very difficult, though. Impossible, actually

Your hypothetical model and "one way crushdown" is off-topic to the design of the WTC towers and how they collapsed on 9/11.