Truss Failure Theory Inconsistent; Critically Flawed

Originally posted by esdad71
My thoughts have always been that the accident exposed the weakness of the actaul buildings, and that due to design, it was very vulnerable in this type of attack. Read the history of the building ot the towers, the codes that were not adhered to, the construction after the WTC bombing in 93. I mean, could you imangine the lawsuits if it came down to the fact it was the poor construction that aided in the collapse. You could also be looking at manslaughter charges for each death, right?

I thought this WAS the official explaination. Truss failure due to type of construction/design? Then, why the need for lawsuits and manslaughter charges?

I have a question about this though. Why would government agencies (9/11 Commission, FEMA & NIST) and Silverstein cover up for a contractor? That just doesn't make sense to me. If a building I'm working on fails either because of design or faulty construction, the government isn't going to cover it up for me or the contractor. Actually, I think they would go after it if they found out it was designed poorly or constructed poorly...it certainly would redirect the accussations off the government's (or Silverstein's) back. Again, what interest does the government or Silverstein have in covering up for a contractor or designer?

Originally posted by BigTrain
And bsbray, did these "tests" also include heavily loaded, deformated and smashed floor trusses that occured after a plane smashed through them, didnt think so.

Actually, that's a good question. Did they incorporate these things into the tests?

Read the book 102 minutes, and it will explain the collapse, and the damage. It contains dialogue from the man who stated that the WTC could withstand a strike, stating that he can see the damage to he floors, and that they need to get everyone out. This is proof that the

It is about reading all material, whether it is on Prisonplanet, CNN or ATS and making your own, informed analysis.


Some of the 'eyewitness' accounts of the bombs are attributed to initial calls that were made to EMS and the PA, some stemming from the second tower strike, since many thought it was still an accident and an explosion, and not a terror attack.

Here also is a eyewitness account that states he watches the building topple and shift to the side, and then collapse.

www.apfn.org...

Originally posted by BigTrain
And bsbray, did these "tests" also include heavily loaded, deformated and smashed floor trusses that occured after a plane smashed through them, didnt think so.

This would not matter unless you think the buildings should have collapsed from impact damage alone. This includes partially damaged trusses. If you think that the buildings should have collapsed from the trusses that were destroyed during impact, then, obviously, you're mistaken.

If you, like NIST (which took many liberties in trying to prove its case), are out to prove that additional trusses failed from heat-related damage, leading to collapse, then you would not be testing the impact-damaged trusses, but the vast majority of trusses that were still intact and needed to fail, in theory.

heavily loaded

The trusses were not load-bearing except for the floor loads, and then they were designed to hold large crowds of people in addition to office supplies, without failure. There would have been no heavy loads on the trusses on 9/11, on those floors.


Again, those trusses would not fail, and have not failed, in any tests that I am aware of, whether by NIST itself, or organizations like British Steel, etc., despite controlled heating of steel systems to as much as 600 C.

[edit on 3-8-2006 by bsbray11]

Poor construction "aided" in the collaspe is what I was stating, not that it what is bieng covered up. I was trying to express to make sure if you were interested in why it failed, that you should study a bit about the design and construction, first envisioned by a Rockefeller and it came to be in the 70's. It was a new idea, and it was created with making sure that every square inch that could be rented, could be. This included the original stairways and elevators designed as they were.

The WTC was a marvel of the modern era, and it's design weakness was shown that day. THe way the planes were flown in at an angle for maximum effectiveness, and they did well. Most of the escape routes were gone after the impacts. Column failure was occuring at this point, and the fires were beginning to spread and intensify with the office materials to burn. The removal of some core columns then meant weight was distributed to the other core columns. Take a piece of paper, and put it on top of 12 pencils, arranged in a square. If you take away the columns, what happens? The paper bends. Now, Imagine if you will that day when suddenly, the top 20 floors were suddenly supported by a 1/3 to a 1/2 of it's support core columns(check the reports), the wieght is distributed, but how long can that occur. Steel at that point would not need to melt, but be heated enough to weaken, allowing the building to basically fall apart from inside out.

Is it so hard to imagine this is what happened, because this is what I see after all the research i have done. It is a miracle more did not die that day.

Originally posted by bsbray11
The trusses were not load-bearing except for the floor loads, and then they were designed to hold large crowds of people in addition to office supplies, without failure. There would have been no heavy loads on the trusses on 9/11, on those floors.

[edit on 3-8-2006 by bsbray11]

That statement is absurd. No loads on the trusses,!?!?!?!? Do you understand what your saying. So did they just come in the night and take away the office furniture and cabinets and concrete floor that sat atop the trusses?

What do you think happened to the weight and debris of the floors that were smashed by the plane? Did they not fall down and add weight to the still intact floors below.

Come on man, no loads, give me a freakin break!

Train

Originally posted by esdad71
Poor construction "aided" in the collaspe is what I was stating, not that it what is bieng covered up. I was trying to express to make sure if you were interested in why it failed, that you should study a bit about the design and construction, first envisioned by a Rockefeller and it came to be in the 70's. It was a new idea, and it was created with making sure that every square inch that could be rented, could be. This included the original stairways and elevators designed as they were.

The WTC was a marvel of the modern era, and it's design weakness was shown that day. THe way the planes were flown in at an angle for maximum effectiveness, and they did well. Most of the escape routes were gone after the impacts. Column failure was occuring at this point, and the fires were beginning to spread and intensify with the office materials to burn. The removal of some core columns then meant weight was distributed to the other core columns. Take a piece of paper, and put it on top of 12 pencils, arranged in a square. If you take away the columns, what happens? The paper bends. Now, Imagine if you will that day when suddenly, the top 20 floors were suddenly supported by a 1/3 to a 1/2 of it's support core columns(check the reports), the wieght is distributed, but how long can that occur. Steel at that point would not need to melt, but be heated enough to weaken, allowing the building to basically fall apart from inside out.

Is it so hard to imagine this is what happened, because this is what I see after all the research i have done. It is a miracle more did not die that day.

Being a structural engineer, i take extreme issue with that statement of poor design. The design was the sole reason why we did not witness an immediate collapse that day. Incredible load transfer ability and redundancy.

If you think that maximum rental space was a factor only considered in the WTC you are sorely mistaken. As with everything man, skyscrapers are no different. How can we make the most money?

Train

Originally posted by BigTrain

Originally posted by bsbray11
The trusses were not load-bearing except for the floor loads, and then they were designed to hold large crowds of people in addition to office supplies, without failure. There would have been no heavy loads on the trusses on 9/11, on those floors.

[edit on 3-8-2006 by bsbray11]

That statement is absurd. No loads on the trusses,!?!?!?!? Do you understand what your saying. So did they just come in the night and take away the office furniture and cabinets and concrete floor that sat atop the trusses?

I think you missed this:

Originally posted by bsbray11
The trusses were not load-bearing except for the floor loads, and then they were designed to hold large crowds of people in addition to office supplies, without failure. There would have been no heavy loads on the trusses on 9/11, on those floors.

Pretty bad reading comprehension if you ask me.

Originally posted by BigTrain


Being a structural engineer, i take extreme issue with that statement of poor design. The design was the sole reason why we did not witness an immediate collapse that day. Incredible load transfer ability and redundancy.

If you think that maximum rental space was a factor only considered in the WTC you are sorely mistaken. As with everything man, skyscrapers are no different. How can we make the most money?

Train

Okay, maybe you're letting your personal bias affect your judgement on this topic. I've just witnessed you misreading one member's post and then taking another member's post and responding with really bizarre - AND UN-PROVABLE - statements.

1. bsbray11 didn't say the floors didn't hold any load, so we've got that resolved.

2. esdad's comments were toward the notions that the floor truss connections on the perimeter columns were under-bolted. It has been OFFICIALLY stated that this was a reason the towers might have experienced progressive collapse.

Now - I'm not sure why you're taking that comment personally (unless you were involved in deciding that a single-bolt construction was okay). But the statement in refutation that "The design was the sole reason why we did not witness an immediate collapse that day." is unfounded, and hyperbolic B.S., and it doesn't help ANY in this discussion.

So - while I'm very glad to find out you're a structural engineer and hope you'll stick with this discussion - I hope you'll can the attitude (which has a bit too much pomposity and infallibity to be helpful), and help us analyze this situation in a logical fashion.

Valhall
Yeah, I would think this implies downward motion of the core, pulling the floor trusses with it.

Finally..




My question above and beyond all of this is if the truss theory is 100% correct, which I don't think it is, how did the core ITSELF just buckle and come apart below the strike area and just fall 'out of the way'? The core was the strongest point of the building as far as I'm concerned and I don't see how even multiple floor/truss failures would cause the core consisting of 47 rather large box collumns (all tied together mind you) to just 'disintegrate'. I could see floors collapsing AROUND the core, breaking their connection points with the core and falling off/around it but you expect me to believe that the core would give up the ghost so easily just because some floors collapsed around it?? Nah.. not buying into it. I'm also not buying any of the 'pancake' balogne that gets expounded on.

MY question is this.. how was the CORE taken out?

The north tower in particular had 90 FLOORS under the damaged area that just conveniently 'disintegrated' after the collapse started. I'm sorry to say to all you guys but 90 floors of box collumns.. (X 47, ALL INTERCONNECTED BY BEEFY SPANDREL PLATING and MORE) do not come apart as fast as they did on 911 unless they were 'helped' along somehow.


Valhall, I respect your balcony analogy but how many 'balcony' failures have ever taken out an entire building?

Let's go over this again:

47 box collumns for the central core... Designed mainly for the vertical gravity load of the building.

61 (that's right, 61) 14-inch steel box columns, spaced 39 inches on center comprised the "perimeter tube".. Designed mainly for lateral loads such as wind shear and such. (This "perimeter tube" ALSO had some gravity load bearing capability, more than we think I imagine.) One source I have seen states that the approximate maximum wind shear force that a single face needed to withstand would be somewhere in the vacinity of 11,000,000 pounds!.. That's how STRONG this perimeter tube itself was.. (It was weaker STILL than the inner core structure itself so keep that in mind).


In order for the building to fall the way it did the CORE had to be knocked out first, especially at the base before the building could even fall as fast as it did, and it looks to me that's exactly what happened. If the weight of the material above the 'failure' point was enough to pancake or pull apart the core below it, the building should have fallen MUCH slower and probably less symetrically I imagine. Don't forget that much of the building was being ejected 'out of the way' so less weight there to support any truss or pancake theory. (At least global ones)

The core failing and falling 'inside the tube' explains everthing as far as I'm concerned.. but my question again is how did the core fail?



Also, don't forget about the video and multiple eyewitness testimony of the ground shaking a few seconds before each collapse. I believe this shaking was caused by the core of each building being disconnected from the ground in short time. Why did the building not collapse immediately after this 'disconnect'? because it would have taken a few seconds for the weight that the core WAS holding up to be transfered over to the 'perimeter tube' which of course could not hold the building up for very long. The core proceeded to fall 'inside' the 'tube', the inner and outer core of the building essentially ripping each other apart, pulverizing all the building content in the process.


I had a friend the other night arguing with me over how, if the core was knocked out from the bottom up, why did the building fall from the 'top down'? I kept citing to him how the outer perimeter 'tube' was constructed and how strong it was and he finally got it.

If I recall, most demolitions are done this way.. 'explosives' are actually fired from the ground up in sequence. Do I really need to post links to substantiate this?

My 2 cents for the night.

[edit on 4-8-2006 by TxSecret]

TxSecret,

Well, I'll just go back to one of the things that perplexes me so much. In order to do this:







Something has to have already have happened to the core....else it would be sticking out the backside of the building. So, as I've asked before and didn't really get a response from anybody, how do you apply the "hat truss failed and everything started pancaking" theory to a building that is showing signs that a catastrophic failure has already occurred in the core and has 30 stories tilted off at about a 20 degree angle?

I've got something else that really hasn't been addressed that I first brought up in this thread

www.abovetopsecret.com...

I first noticed it in this video which has a zoom in of WTC 2 just at the time of its collapse

video.google.com...

And this is what I asked:

What odds would you put to large-scale events happening in both towers at the same time? Remembering, of course, that the two towers were struck about 15 minutes apart, how probable would it be that combustion/heat induced explosions would take place in both buildings at the same time? Or that one building would collapse at the same time the other building suffered a significant combustion/heat induced explosion?

I personally place the odds of this happening extremely low. But the Trinity video captures visual evidence of possible explosions in both towers at almost the exact same time. That's extremely interesting.

I also pointed out that in the second video AgentSmith listed, at 41 seconds into the video, an percussive sound is recorded that sounds (to me) like some type of explosion:

video.google.com...

So I went looking at videos that had both towers in the frame at the time of WTC 2 collapse to see if I could find any more visual evidence of a possible large-scale event in both towers at the same time.

In this one...Watch the left corner of WTC 1 at and just after the collapse of WTC 2 - watch the billowing new smoke. There was no smoke in that area and then all of a sudden, at the same time WTC 2 collapses, something huge happens in that corner of WTC 1.

images.indymedia.org...

Marked up frames of above video:

www.thedivinesibyl.com...

Look here at this one (sorry I can't find the individual file so you'll have to open this atrocious page with multiple videos playing - uggh). Next to the last video playing with the title above it "From German Television". Watch the south face of WTC 1 just as WTC 2 starts collapsing. This is some of the best evidence here of a major explosion in WTC 1 at the same time something made WTC 2 fall.

thewebfairy.com...

Marked frames from the above video to show the area you should be watching on WTC 1 at the time WTC 2 collapses.





And the reason I think this particular issue is relevant to this discussion is because we're now discussing the fact that it would seem the core would have had to fail catastrophically before the tilt/collapse occurred in WTC 2.

No, bsbray, I think you missed this....

Originally posted by bsbray11
There would have been no heavy loads on the trusses on 9/11, on those floors.

Valhall, stop trying to play dad here. You think my comments are B.S. I'll show you B.S. How about you trying to describe the collapse of WTC 2 as two solid blocks,

Originally posted by Valhall

ya, im sure thats how the WTC towers would have acted, as solid masses, HAHA, laughable. The core punching through the top, again, laughable, the back side remaining hinged, laughable. I guess you too believe the smashed floor debris from the collision just disappeared and applied no load to the intact floors below, hence adding the "heavy loads" bsbray seems to miss.




[edit on 4-8-2006 by BigTrain]

Heres another thought people. where do you think most of the aluminum debris and the rest of the plane ended up? Did that too dissappear, maybe you would like to think about the weight of the plane debris and add that to the floor debris weight, or I guess the trusses didnt experience any "heavy loads" that day.

Big Bad Train!

Originally posted by BigTrain

ya, im sure thats how the WTC towers would have acted, as solid masses, HAHA, laughable. The core punching through the top, again, laughable, the back side remaining hinged, laughable. I guess you too believe the smashed floor debris from the collision just disappeared and applied no load to the intact floors below, hence adding the "heavy loads" bsbray seems to miss.


[edit on 4-8-2006 by BigTrain]

Where did I say I thought it acted as two solid masses? The diagram was to show the envelope of the structure. Would you like me to go in and draw little lines on it for the trusses and little black dots for all your single-bolt connections you're so proud of?

Just let me know...I'll dress it up however you need it so that you can get your required comfort level.

BigTrain, your theory goes something like this...

Planes hit buildings (Two different planes hit at two different angles at two different areas on two different towers). Fire rages under floor trusses above impact areas.
Trusses expand/warp due to intense heat. Bolts stay attached to connection points at both ends, because bolts need more heat to fail than trusses. Maybe bolts rip out of plates at connections, maybe something else happens. Whatever happens, floor trusses ultimately collapse, and the weight of the building above, in transitioning from static weight to dynamic forces, turns the structure below into dust, causing the building to fall at "near free fall" speed.

...is that accurate?

You go on to question if certain members think the aluminum and other materials from the plane "just disappeared".

The fact is that the plane materials DID, effectively, disappear -- when the FEMA officials closed off the area and allowed a private demolition company to collect and ship all the evidence from the catastrophe away.

All that's left (for the most part) is photographic and video documentation, eyewitness testimony, and a three page spreadsheet listing the steel parts collected for use in investigations.

The question I would pose to you is:
Do you think that, as you are clearly satisfied with the results of the investigations explaining the truss failure theory, the government agancies did a wonderful job in collecting all the needed elements to paint a clear picture of the overall events of that day?

Don't you have questions regarding the speed of the collapses?

Don't you wonder what happened at WTC 7? And why FIST says in their executive summary for WTC 7 that no steel was recovered from that building...so they had to use documents from time of construction to complile their results?

Don't you want the government to release findings that no explosives or incindiary device use were found? Instead of investigating this aspect, they totally ignore that these things may have played a role somehow...

The findings I've read in reports issued by authorities leave alot of unanswered questions. And I think to argue over whether trusses failed or not is moot, considering the destruction of evidence. The fact is that ultimately all the structural elements finally failed completely...

The trusses may have indeed been the weak point where the collapses started. But how can we be positive that other things didn't happen, when evidence (from photos, video, and eyewitness testimony) of explosions, showers of molten metals (steel, not aluminum) and pools of still melted metal under the debris for weeks are things that needed to be addressed and ultimately weren't.

They may as well have had Halliburton clean up the site and do all necessary investigations...

Originally posted by cryingindian


They may as well have had Halliburton clean up the site and do all necessary investigations...

Nah - they would have done a better job.

Originally posted by BigTrain
No, bsbray, I think you missed this....

Originally posted by bsbray11There would have been no heavy loads on the trusses on 9/11, on those floors.

I was pointing out that the trusses would have been under no unusual stress that day to complicate things for them.

Again, they were designed to hold large, standing crowds of people, in addition to all of the expected loads from office supplies, all without damaging the structure. There were no such crowds of people hanging around on these impacted floors on 9/11.

Do you seriously think that the truss loads were that bad on 9/11 for all of the intact trusses, which was nearly all of them?

Originally posted by bsbray11

Originally posted by BigTrain
No, bsbray, I think you missed this....

Originally posted by bsbray11There would have been no heavy loads on the trusses on 9/11, on those floors.

I was pointing out that the trusses would have been under no unusual stress that day to complicate things for them.

Again, they were designed to hold large, standing crowds of people, in addition to all of the expected loads from office supplies, all without damaging the structure. There were no such crowds of people hanging around on these impacted floors on 9/11.

Do you seriously think that the truss loads were that bad on 9/11 for all of the intact trusses, which was nearly all of them?

They were not designed to hold large standing crowds, floors are not designed based on occupancy, they are based on use, which is based off probabiity. I believe office live load, off the top of my head, is like 50 psf. The point is, these arent super floors.

bsbray, take this scenario, looking from many photos, it would appear that 4-5 floors on the impact side were destroyed by the impact. That means these floors would have been smashed and debris would have fallen onto the floors not destroyed by the plane impact. Do you not think that all this smashed floor of concrete and steel would not impart a significant load on the existing floors? Remember, all that office equipment, and the plane all had to go somewhere. And you're saying no significant heavy loads. If you still believe me, then where did the debris come to rest after the impact?

Train