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WTC construction manager speaks of the resilience of the twin towers

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posted on Dec, 23 2009 @ 02:37 AM
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Originally posted by bsbray11

Originally posted by thomk
There is no way on earth that Skilling or Robertson or any other engineer on the planet could possibly have done any sort of MEANINGFUL study to prove the resilience of the towers to airplane impact in 1964.


Haha, how old are you? I wonder because you call us "kids" but I've had a 90-year old electronics professor who could calculate things in minutes by hand that would leave you scratching your head (including the younger instructors, in their 40s). These guys knew the ins and outs of the formulas and what realistic variables were or how to gauge them using basic physical measurements alone.

You assume you would need a computer to do this. No way. Remember that we taught the computer the math it knows, aka top-down programming. We have known this math for decades, if not centuries in many cases. Older generations of engineers who were forced to rely on calculating things by hand were extremely proficient at it.

[edit on 17-12-2009 by bsbray11]


I'm 57. I've got a BS Mechanical Engineering from (IMO) the best Ivy League engineering school (Cornell).

Now, what do you know about stress & strain analysis as done traditionally (before FEA)?

I have an exquisite appreciation for the analyses that were done in the old days. I've done many. Using FEA seems like cheating. Much easier. Much faster. You don't need 1/100th the judgment (or the bag of tricks) that separated the top notch engineers in the old days.

You learn a FEEL for the answers by virtue of comparison to similar problems you've worked on in the past.

There was nothing that Skilling or Robertson could have used to give them a "feel" for a plane crashing into the towers.

Your comment about "we taught the computer to do the math" proves a woeful lack of understanding how you would set up or perform a MEANINGFUL analysis.

Why don't you give me a brief description of how you'd solve a system of a couple of million simultaneous equations without a computer.

Tom




posted on Dec, 23 2009 @ 02:41 AM
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Originally posted by Lillydale
Well it seems you have quite a few claims to back up. I am patient.


You better be.

Your attitude means you get ignored.

Pester someone else.

Tom



posted on Dec, 23 2009 @ 02:43 AM
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Originally posted by thomk
Why don't you give me a brief description of how you'd solve a system of a couple of million simultaneous equations without a computer.


I wouldn't know, but wouldn't you be more curious to ask Skilling how his team performed their own analysis instead, since that was the firm that did that particular analysis and you seem to have a problem with it? Instead of just saying they couldn't have had any idea how to do it?



posted on Dec, 23 2009 @ 05:39 AM
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Originally posted by thomk

Originally posted by Lillydale
Well it seems you have quite a few claims to back up. I am patient.


You better be.

Your attitude means you get ignored.

Pester someone else.

Tom


I know. My pursuit of real answers that are not lies or disinfo must come across as quite an attitude to people that wander threads spreading false statements and peppering them with personal attacks based on nothing.

Hmmmm. you purposely present false information and then just attack anyone that asks for proof and this makes you mad? You are kind of lucky you are not on all ignore lists.

It is funny. When I ask some OSer to back up his craziness, it just makes him soooo mad. When I push the issue, I get ignored. The OS must be soooo true that it just really upsets people when you want them to actually prove the lies they spread. Ignore me all you like. It will not make your stories any more true.

You could have backed up your claims if they were true.

Instead asking you to back them up gets me ignored.




posted on Dec, 23 2009 @ 07:07 AM
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Originally posted by thomk
You know, nut, it's kind of touching, the deferential respect you pay to us in that statement above. (I'm a mechanical engineer, 35 years experience). Why does it strike that you're not quite that sincere?


It should strike you as sincere because I am speaking of myself also. I am a professional engineer (PE) in Civil Engineering with 15 years of experience in transportation, geotechnical and structures. All disciplines I have had to utilize in my career as a construction manager.


While engineering starts out with the same (nah, somewhat above average) competence as any field, industry is intolerant of incompetence. So, you're given about 5 years or so as a baby engineer to show what you can do. If you prove yourself incompetent as an engineer, you're shunted off someplace else. Sometimes into engineering management.


I must be doing well then with 15 years experience and a PE license to back it up.


The good news is that, if someone has simply survived as a working engineer for 20+ years (and is not in a union or gov't service), then you can have a fair assurance that they have a certain minimum level of competence.


I only have 5 years to go until you consider myself competent.

BTW, did you know that Robertson was only 14 years into his career when he helped design the WTC?


This also explains clearly why there are virtually NO experienced working engineers in AE911T.


I don't belong to that group. I don't need a group to define who I am and what I believe and know.


First, you've got VERY few engineers who have any expertise that is pertinent to the collapse of the towers. (Definitely structural & mechanical. & some civil.)


Since structural is a subsect of civil, I have no idea why you listed them twice. Unless you ment the geotechnical (soils) aspect of a civil engineer?

But, regardless, they all belong under the category of civil.


Nonetheless, I find your "respect" for engineers less than convincing. Where is this respect for the 1000 or so incredibly successful & experienced engineers from NIST, academia & industry that contributed to the NIST report?


I don't need to show "respect" to my peers. I am able to critic them without impunity.


Now, you & this guy ANOK have said a bunch of things that show that you also don't understand much about why the buildings stood,


That's interesting as I have studied structural engineering. Care to debate me on any subject within the realm of structural engineering?


or why they fell down. If you've got some specific questions about them, feel free to ask.


I don't need to ask you. I am my own source.

[edit on 23-12-2009 by Nutter]



posted on Dec, 23 2009 @ 07:25 AM
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To tomk and nutter....

I don't understand why people say they have a hard time pulling up the blueprints for the WTC's. They seem to make it sound as if it is some clandestine operation that has "covered up" the design of the WTC's so no one can get answers.

If anyone cares to look, here are the blueprints for the WTC's.

911research.wtc7.net...

I am competent and capable of reading these design blueprints because I designed buildings for 15 years. I am not a PE nor am I an architect. I worked for my in my fathers architectural firm for 15 years and was involved with the design of many different styles of buildings.

I still cannot figure out how a plane could take out enough structural columns to have made the buildings "pulverize" themselves.

tomk and nutter....care to give us your take on the structural integrity of the buildings? And also, how did the "turrurists" ever manage to do a study of the buildings blueprints and come to a conclusion that by flying a plane into a certain floor, it would have "total structural fail" capabilities?

I have never understood that. These guys surely didn't just wake up and say, "Let's fly some planes into some buildings and see if they fall"!!!

From what I see of the design of the buildings and what the architects and engineers have said about the WTC's, I personally would have picked some other buildings to have flown a jet into if I was planning a 911 attack.
I mean, they DESIGNED the buildings to withstand a whole lot of stress and I don't see that an aluminum plane that dispersed most of it's energy (fuel) out of the side of the building, would be capable of such destruction.

How do you (tomk and nutter) feel about the "squibs" coming out the sides of the buildings pre-collapse?

peas



posted on Dec, 23 2009 @ 07:43 AM
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Originally posted by theonlyrusty

To tomk and nutter....

I don't understand why people say they have a hard time pulling up the blueprints for the WTC's. They seem to make it sound as if it is some clandestine operation that has "covered up" the design of the WTC's so no one can get answers.

If anyone cares to look, here are the blueprints for the WTC's.

911research.wtc7.net...


One thing to understand about structural drawings and specifications.

The drawings will have many more pages than just the architectural drawings. Those are only the architectural drawings. You can verify this by the page number A-* The A means architectural.

These sets of drawings are missing the most important subset, the structural drawings. Which would be designated with S-* . There are also, mechanical drawings (M-*), plumbing drawings (P-*), electrical drawings (E-*). etc.

Also, the most important information is missing. The specifications themselves. These should easily be thousands of pages long. Specifications tell us everything from the materials to use to how to build it. Meaning there is a lot of information in the specifications.


I am competent and capable of reading these design blueprints because I designed buildings for 15 years. I am not a PE nor am I an architect. I worked for my in my fathers architectural firm for 15 years and was involved with the design of many different styles of buildings.


Then you should know that the architectural drawings are not a complete set of drawings and specifications.


tomk and nutter....care to give us your take on the structural integrity of the buildings? And also, how did the "turrurists" ever manage to do a study of the buildings blueprints and come to a conclusion that by flying a plane into a certain floor, it would have "total structural fail" capabilities?


I believe the conspiracy is that the government is hiding that our buildings are made pretty crappy with crappy materials.

Things like gypsum are used for wallboard that if ignited with enough heat and enough aluminum (powdered) can cause a thermitic reaction (like what happened in the debris pile IMO).

Also, construction workers love to cut corners. That is what my whole carreer is about. Making sure that the construction workers build according to the drawings and specifications and don't cut corners.

We can not always be there though. As right now, I'm having an issue with some asphalt not staying down. The reason: I noticed they were not filling the base in lifts and compacting it. Now it's a total mess that the contractor has to fix on a daily basis. It's temporary asphalt (we are going to scarify and repave at a later date) that is why it's not such a big deal now but they still need to excavate the area and recompact the base....which costs money.


How do you (tomk and nutter) feel about the "squibs" coming out the sides of the buildings pre-collapse?


I don't know of any quibs pre-collapse. During yes, but not pre.

I'm going to go with air pressure (either by way of explosives or by the building falling). In other words....I don't know.


[edit on 23-12-2009 by Nutter]



posted on Dec, 23 2009 @ 08:40 AM
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Hi nutter...

The link I provided actually gives you ALL blueprints.
You just have to scroll on the right side of the title bar and it pulls up every floor for Architectural, Mechanical, Electrical, Structural.
I hope I at least learned something in all those years of reading blueprints...(hahahah)

I'm sure I can get the specs. as well. I have seen some somewhere but I don't know if those are what I would be looking at as much as the blueprints if "I" was planning a 911 attack.

Let's forget what we know about what happened on 911 and pretend we are planning the attack. What do you see, or not see, that would give you the pertinent information you need to make a decision to fly a plane into those buildings? I can see from just the structural drawings that a plane crashing into the building certainly might have weakened it just a bit, but that's what the loads are figured for. When the rest of the building spread the stress out, did it in fact jeopardize the entire structural column system to the point of pulverizing concrete/steel columns filled with rebar?

When we designed a multi - floor warehouse for example, we had to figure out what would happen if a guy on the second floor went crazy with a forklift...Could he penetrate a wall section and crash down onto the parking lot? If he could, we changed the design....Seems like this had to be applied to the WTC design as well.

Just curious....and it is really enlightening to work this thing backwards...say, from the pre impact scenario.
Did the hijackers/engineers know they needed to hit a certain floor or many?
Would the results have been the same if they had hit the 102nd floor or the 20th floor?

I think we can learn alot from questioning the pre impact stage and the blueprints... jmho...



peas



posted on Dec, 23 2009 @ 09:15 AM
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Originally posted by theonlyrusty
The link I provided actually gives you ALL blueprints.


No it doesn't. It gives SKA, SA, A-A and nothing else. Unless I'm missing something?


You just have to scroll on the right side of the title bar and it pulls up every floor for Architectural, Mechanical, Electrical, Structural.


I don't see where this feature is.


Did the hijackers/engineers know they needed to hit a certain floor or many?


I believe they intentionally tilted the wings so as to hit as many floors as possible.


Would the results have been the same if they had hit the 102nd floor or the 20th floor?


No. The 102nd's floor steel was not as strong as the 20th floor would need to be. Although having not worked out the minute of stresses I can't say for sure.



posted on Dec, 23 2009 @ 09:34 AM
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O wow.... I just watched the Jesse Venture Conspiracy Theories episode on the 9/11 conspiracy. All I have to say is wow.

Everything that was said makes sense, and is backed up by credible engineers and individuals. Only to be silenced by the government. I haven't had time to do my own research into the matter yet. But if everything is true. There absolutely needs to be an investigation. And people need to be held accountable for their ignorance.

Interesting, conclusions drawn about tower 7. Explosive thermit painted onto the walls. Now the security of tower 7, seems impenetrable. Agencies such as the CIA and FBI occupied this building. Certainly not an easy building to bring down, without anybody knowing. Unless of course, an explosive is painted on the walls, under the noses and suspicions of everybody in these buildings.

then the black boxes that were found at the WTC site that supposedly were never found. According to the FBI and NTSB. I'll let you draw your own conclusions, but I definitely recommend watching this.

My personal views are very different now after watching this. Can anybody support the validity of this episode and claims?





[edit on 23-12-2009 by xX aFTeRm4Th Xx]



posted on Dec, 23 2009 @ 09:48 AM
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Originally posted by PersonalChoice
reply to post by xX aFTeRm4Th Xx
 


Well, Ill take you and Tomk up on your offers to field questions, especially since both of you seem to have a lot of experience.

First, I know you can both only speculate, but there seems to be only two answers to this question that either side will tell you.

Those answers being...

1) by product of thermitic reaction that began to finally leak out of the building due to the sagging of the floors.

2) Some sort of back up batteries that were cooked to bright orange flowing liquid on the floor slab until it finally began to sag and some of this molten material began to leak out.

All of this just moments before the collapse.

The question should be obvious by now(Jeopardy anyone lol):

What was the molten material flowing from the south tower before the collapse?

What do you think caused it to form and flow at that time?

I guess I'll just start off with that, and see what kind of response I get. I thank you(both) in advance.


What was the molten material?

Short answer: I don't know for certain. But I will put limitations on what it could possibly be.

It could not be steel. While there are a couple of possible speculation that have been offered regarding local "hot spots" that could get hot enough to melt steel (battery current or fed by oxygen generators), I find the conditions necessary to generate that amount of material to be too improbable to sustain long enough to produce that amount of molten steel.

Longer answer: Most likely a mixture of mostly aluminum and 500 other materials that are typically in an office and an airplane.

I am 100% certain that it had nothing whatsoever to do with thermite. Or Thermate. Or thermite. Or nanothermite. Or superthermite. Or superthermite with conventional explosives. It takes about 2 pounds of thermite to melt one pound of steel. That was a LOT of material that was flowing out of there. It probably measured in the tens of tons. That means (2x tens of tons) of thermite would have been needed to melt it, firing off very close to the edge of the building. With none of the characteristic blinding white light that is typical of the thermite reaction being visible thru glass & open gashes? No way. Thermite did NOT, could not possibly, have melted that material, without being blatantly obvious to the cameras.

And it also had little to do - overall - with the collapse. It was simply too local and concentrated an event.

Those buildings were huge, with massive amounts of redundancy built in. That had been demonstrated by their survival of the massive damage from the initial impacts.

No matter what was done in one small local area (even if you did, somehow, melt some local columns), that would not have toppled the towers. There HAD to be a process that was widely spread throughout the structures.

This effect is clearly shown in the NIST results.


Tom



posted on Dec, 23 2009 @ 10:33 AM
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nutter...you are correct.

You cannot pull up any of the links anymore for those plans. At one time you could follow the links from that page and it would lead you through the Port Authority pages and to the Fema page and others where you could see 261 pages of WTC plans for the structural, mechanical and electrical ...now all I get is a 404 message and "page not found". I find it hard to fathom that these can be hidden now since the Port Authority was viewed as using "public funds" for parts of the buildings. I used to have the ability to pull up almost any building plan I wanted to and the specs, but those days are gone. Maybe I can pull them up from the Popular Mechanics page...hahah

I like your theory of "tilting the wings" in order to do as much damage as possible. Noticing that NIST and other studies rarely even take into consideration the core columns, what was it, in your estimation, that would have totally "pulverized" them. I would have expected to at least see some very large sections of the core columns intact after the collapse. I am also in question as to why some of the structural engineers (private investigation vs government) have such differing views on the exact cause of failure to the buildings. I never realized that the NIST specs. could be looked at so differently by varying firms.

Did the outer shell and floor connections "outside" the core columns actually have enough energy to pulverize the inner columns? Seems to me that the majority of energy of the collapse was naturally favoring going towards the path of least resistance...which, imho, would have been "away" from the center of the building. I am NOT a structural engineer, nor have I claimed to be and I would feel fairly confident in hearing YOUR explanation as to what caused the failure. You seem to have nothing to gain or lose by putting your expertise out there, and it doesn't sound like you are in the "coffers" of any government organization.

Albert Einstein said, "The only real valuable thing is intuition". When I saw the buildings come down on 911, my first thought was demolition. What was yours?

I have been wrong before and I will be wrong again many times, but doesn't something about the collapse of the buildings seem strange? Would the hijackers really have had to have known the actual structural loads of the floors and columns to make an intelligent decision as to where to hit the building? And we haven't even hit upon WTC 7...

I read in one report that the buildings were actually "overdesigned". I realize that design in the 60's and design today are different, but can you glean any info, from just the architectural drawings, that would lead you to believe that you could cause "total failure" to the WTC's by hitting them with a plane? If they had hit them multiple times on different sides, I could fathom the story easier, but then again, I'm not a P/E.

Thanks for the insight...I try not to be on either side of the fence on the entire issue but I suppose one can see which way I am leaning...

peas



posted on Dec, 23 2009 @ 10:52 AM
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Originally posted by theonlyrusty
I am NOT a structural engineer, nor have I claimed to be and I would feel fairly confident in hearing YOUR explanation as to what caused the failure.


Actually mechanical engineers would know more about the mechanics of building failures than I would. I only learned how to design and build them. Not have them fail.


You seem to have nothing to gain or lose by putting your expertise out there, and it doesn't sound like you are in the "coffers" of any government organization.


I don't have anything to gain or lose. I haven't written a book, paper or anything else. And I'm not employed by the government.


Albert Einstein said, "The only real valuable thing is intuition". When I saw the buildings come down on 911, my first thought was demolition. What was yours?


Shotty workmanship and materials.


I read in one report that the buildings were actually "overdesigned". I realize that design in the 60's and design today are different,


Today's design is totally different than that in the 60's. Back in the 60's they used what is known as ASD (Allowable Stress Design). In the 80's a new form of design was introduced and adopted called LRFD (Load and Resistance Factor Design).

I'm more familiar with LRFD than ASD, so their design would be different than I would go about it today.


but can you glean any info, from just the architectural drawings, that would lead you to believe that you could cause "total failure" to the WTC's by hitting them with a plane?


I'm not sure and I remain on the fence on this issue. I can see it happening but then again, I see what happened in the aftermath (the cover-up) and it makes me scratch my head.



posted on Dec, 23 2009 @ 11:10 AM
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reply to post by thomk
 


I agree. I don't think it was steel dripping out of the corner of the building.

I would like your thoughts on my theory about natural thermitic reactions. Although my theory doesn't involve the actual cause of the collapse.

I have a thread out there where I show a video of a man using only plaster and powdered aluminum to create a thermitic reaction.

I also show a video of a man using 2 steel balls (one wrapped in aluminum foil) to create sparks of thermite.

My theory is that either the plane impacts or the collapses caused the aluminum to powderize enough with the plaster to cause thermitic reactions. I believe this could be the answer as to what was burning so long in the rubble piles.

I'd like to know your thoughts on the matter. Thanks.



posted on Dec, 23 2009 @ 12:44 PM
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Nut,


Originally posted by thomk
Why does it strike me that you're not quite that sincere [about the the deferential respect] ?


Originally posted by Nutter
It should strike you as sincere because I am speaking of myself also. I am a professional engineer (PE) in Civil Engineering with 15 years of experience in transportation, geotechnical and structures. All disciplines I have had to utilize in my career as a construction manager.



Well, this should be a treat then. You are one of the extremely few experienced engineers that I've been able to find on these boards. And only the 2nd who appears to be "on the other side".


Originally posted by Nutter
I must be doing well then with 15 years experience and a PE license to back it up.


We all have our personal definitions of "doing well". You seem well on your way.
__


Originally posted by thomk
The good news is that, if someone has simply survived as a working engineer for 20+ years (and is not in a union or gov't service), then you can have a fair assurance that they have a certain minimum level of competence.


Originally posted by Nutter
I only have 5 years to go until you consider myself competent.



First semantics:
The phrase, "people with more than 20 years of experience (are likely to be) competent" is NOT semantically equivalent to "people with less than 20 years of experience (are likely to be) incompetent".

In general, my (unstated in that post) feeling is that it takes about 5-8 years to emerge from the "baby engineer" state and be ready to take on some real responsibility. This country would do very well to implement an "apprenticeship" program with its newly minted engineers.

Do you disagree?

Second, poor use of generalization.
Generalizations are appropriate when going from the individual to the group.
They are inappropriate when going from the group to the individual.

"Generally speaking", of course...


Originally posted by Nutter
BTW, did you know that Robertson was only 14 years into his career when he helped design the WTC?


I recall reading that he had no engineering degree when he started on this project. He had some sort of a degree in "General science", and later got his engineering degrees.


Originally posted by thomk
This also explains clearly why there are virtually NO experienced working engineers in AE911T.


Originally posted by Nutter
I don't belong to that group. I don't need a group to define who I am and what I believe and know.



I never said, or thought, that you did.
Meanwhile, do you disagree with my statement about the small percent of experienced structural and mechanical engineers in AE911t within their minuscule percent of all engineer?


Originally posted by thomk
First, you've got VERY few engineers who have any expertise that is pertinent to the collapse of the towers. (Definitely structural & mechanical. & some civil.)


Originally posted by Nutter
Since structural is a subsect of civil, I have no idea why you listed them twice. Unless you ment the geotechnical (soils) aspect of a civil engineer?

But, regardless, they all belong under the category of civil.



There are a thousand different applications of civil. Building roads, dams, bridges, city planning, plumbing & electrical infrastructure, etc. etc. etc.

The ones that have pertinent experience are structural & mechanical.

[End Part 1]



posted on Dec, 23 2009 @ 12:44 PM
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[Part 2]


Originally posted by thomk
Nonetheless, I find your "respect" for engineers less than convincing. Where is this respect for the 1000 or so incredibly successful & experienced engineers from NIST, academia & industry that contributed to the NIST report?


Originally posted by Nutter
I don't need to show "respect" to my peers. I am able to critic them without impunity.



First, every civilized human should show respect to others as a matter of habit. And maintain it, right up to the point that the other person has manifestly demonstrated that they don't deserve it.

Second, as a PE, your Code of Professional Ethics demands that you do so.

Third, you can "critic" [sic] them respectfully. Or you can do it disrespectfully. Your choice, your consequences.

Fourth, you can do so "with impunity" or "without impunity". Here, it is likely to be "without".


Originally posted by Nutter
That's interesting as I have studied structural engineering. Care to debate me on any subject within the realm of structural engineering?


Sure. But let's start with a historical one.

I saw you vehemently defend the position that Skilling, Robertson, et al, analyzed the effect of fire resulting from the plane crash. Every bit of evidence that I've seen, including the Seattle newspaper story you quoted, says that they specifically did not do so.

Do you have any other references to suggest that they did?


Tom



posted on Dec, 23 2009 @ 12:52 PM
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Originally posted by thomk
I saw you vehemently defend the position that Skilling, Robertson, et al, analyzed the effect of fire resulting from the plane crash. Every bit of evidence that I've seen, including the Seattle newspaper story you quoted, says that they specifically did not do so.

Do you have any other references to suggest that they did?


I was going off the quote from Skilling that they analysed the fire. Maybe you could inquire with his firm whether they did or not?


"Our analysis indicated the biggest problem would be the fact that all the fuel (from the airplane) would dump into the building. There would be a horrendous fire. A lot of people would be killed," he said. "The building structure would still be there."


To me that quote says that their analysis included the fire.



posted on Dec, 23 2009 @ 01:05 PM
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Originally posted by thomk
First, every civilized human should show respect to others as a matter of habit. And maintain it, right up to the point that the other person has manifestly demonstrated that they don't deserve it.


I agree. I believe I have been respectfully communicating with you.


Second, as a PE, your Code of Professional Ethics demands that you do so.


I'm not too sure about that. It's a fine line.


Third, you can "critic" [sic] them respectfully. Or you can do it disrespectfully. Your choice, your consequences.


I believe I am always respectful when I attempt.

I can have respect for the engineers of NISt and at the same time think they are mistaken. Just like Dr. James Quintiere, P.E. can.



posted on Dec, 23 2009 @ 01:26 PM
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Rusty,

If you don't mind my chiming in...


Originally posted by theonlyrusty

I like your theory of "tilting the wings" in order to do as much damage as possible.


Nah, he tilted the wings because he started to drift to the right of the tower. You change direction by banking & pulling back on the yoke. Not by skidding the plane with the rudder. This is proven by the shape of the wings' imprint on the towers. He was "pulling Gs" at impact, with the wings bowed upwards.


Originally posted by theonlyrusty
Noticing that NIST and other studies rarely even take into consideration the core columns, what was it, in your estimation, that would have totally "pulverized" them. I would have expected to at least see some very large sections of the core columns intact after the collapse.


Nothing "totally pulverized them". They are all over the place on Ground Zero. In fact, 40+ stories of the partial core are still standing, in both cases, for several seconds after the crush front passes them.


Originally posted by theonlyrusty
I am also in question as to why some of the structural engineers (private investigation vs government) have such differing views on the exact cause of failure to the buildings. I never realized that the NIST specs. could be looked at so differently by varying firms.


There is some healthy debate in the engineering literature about the fine details. For example, Dr. Quintierre, (who is NOT a truther, BTW) believes that the thermal damage to cross trusses started the failure, while NIST's investigation points to creep in the columns.

The reason for the discrepancy & concern is that engineers want to make their buildings robust. And this represents a new threat that they have never considered before.

The sad reality is that this field learns 1000x more every single time a plane crashes, a building or bridge fails, or a shuttle blows up, than they do when those structures land successfully or remains standing (and unstudied).

They are overdesigned, with factors of safety. This hides weaknesses.

It is also an inefficient (in terms of time) to arrive at a "workable" solution. During WW II, we didn't have the luxury of designing planes like that. The fact is that you can converge on a solution much faster by designing things with factors of safety LESS THAN 1, exercise the part, see what breaks, fix that piece & repeat.

The bottom of Long Island Sound is littered with the carcasses of planes that were designed in this "efficient" manner. (Tough on test pilots & their widows, tho.)


Originally posted by theonlyrusty
Did the outer shell and floor connections "outside" the core columns actually have enough energy to pulverize the inner columns?


No core columns were "pulverized". Many on the impact floors were physically bisected, or bent to the point that they could no longer support loads. They were NOT "massive" on the impact floors. They were relatively thin walled box beams & I beams. They were ripped from their supporting structure.

And here is the important parts.

The principle phenomenon that initiated the collapse was relatively low to moderate temperature (300 - 800°C) creep. Once the collapse began, all the support columns (internal & external) could have been made out of "unobtanium". (Which has infinite strength, infinite toughness ("energy absorbing ability"), infinite ductility, whatever you need at the moment.) And it would not have changed the outcome one iota.

The beams (outside of the damaged floors) did not buckle, they did not collapse, except in a small number of cases. Their CONNECTIONS broke. Without the lateral connections, those beams could not even hold themselves up, much less support the weight of the rest of the building.

[End Part 1]



posted on Dec, 23 2009 @ 01:26 PM
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[Part 2]


Originally posted by theonlyrusty
Albert Einstein said, "The only real valuable thing is intuition". When I saw the buildings come down on 911, my first thought was demolition. What was yours?


This is your comment that got me to respond.

Albert was a scientist, not an engineer.
Intuition is good. Analysis is much, much better.

And the FACT of the matter is that any engineer (except very experience structural engineers who direct experience with fire & failure modes of very large buildings) who drew their conclusions from "first impressions" was a fool.

The appropriate course of action in all of these cases (shuttle explosion, dam break, building collapse) is "Don't Guess". Let the experts do their job, look at all the evidence, and THEN start drawing your conclusions.

It is stunning to me to read the "personal statements" of the guys at AE911T and see the number of times "as soon as I saw the towers fell, I knew ...". Amateurs behave like this.

Tom




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