Rotation of the upper section before collapse

[twinstead]

What rational person can't see the buckling?

[GlennB]

...
It is just one big hand wave that the instability of the south wall then spread to the east and west walls. It is not supported by any analysis. In fact the analysis shows they should not have failed and allowed any rotation.

While your theory is that the core was CD'd bringing down the exterior with it, right?

Which would have ripped the exterior columns inwards pdq. So, what caused them to bow, for several minutes in both cases? A really really slow CD?

[TruthersLie]

Glenn.

Of course... and with those squibs going off that increase in pressure, power and ejecta over several seconds....

[Dave Rogers]

It is just one big hand wave that the instability of the south wall then spread to the east and west walls. It is not supported by any analysis. In fact the analysis shows they should not have failed and allowed any rotation.

It's not a handwave, it's an observation. Your choice not to see it doesn't make it invisible to everyone else.

Dave

[twinstead]

What do you mean by "the analysis", Tony? YOUR analysis?

[R.Mackey]

Removing one wall from a four sided structure will not cause rotation. It is actually the walls which are normal to the overloaded or failed wall which would resist the torque in the direction of that wall. In the case of the North Tower it would have been the east and west walls resisting torque towards the buckled south wall.

This is a lie.

The east and west walls do not resist this torque, any more than they would have resisted a wind load on the north wall. This is for several reasons. One is because the load would vary across the columns, with much less total response -- those on one side being in tension, on the other in compression, those in the middle not stressed at all -- whereas the north and south walls would all resist in tension and compression, respectively. Another is because they couple to the core via those flexible truss structures, and those cannot resist being twisted.

You've been already told this, in this very thread.

The NIST calculations for load increases on the east and west walls, due to hat truss redistribution from both the impact on the north wall and buckling of the south wall, show it was no more than 50% while they were capable of handling 500% of the original load on them. It is just one big hand wave that the instability of the south wall then spread to the east and west walls. It is not supported by any analysis. In fact the analysis shows they should not have failed and allowed any rotation.

Their "not supported by any analysis" and "one big hand-wave" is actually several hundred pages of report, backed by one of the most complex modeling efforts in history.

You lie with practically every post now, Tony. This is usually a sign that you should rethink your conclusions.

[Newtons Bit]

Removing one wall from a four sided structure will not cause rotation. It is actually the walls which are normal to the overloaded or failed wall which would resist the torque in the direction of that wall. In the case of the North Tower it would have been the east and west walls resisting torque towards the buckled south wall.

Yes it will. The centroid of the vertical forces from the remaining 3 walls is no longer concentric with the center of mass of the upper block. And considering the upper block is falling, there is thus rotation. Draw a free-body diagram ffs.

The NIST calculations for load increases on the east and west walls, due to hat truss redistribution from both the impact on the north wall and buckling of the south wall, show it was no more than 50% while they were capable of handling 500% of the original load on them. It is just one big hand wave that the instability of the south wall then spread to the east and west walls. It is not supported by any analysis. In fact the analysis shows they should not have failed and allowed any rotation.

Source?

[Dave Rogers]

The east and west walls do not resist this torque, any more than they would have resisted a wind load on the north wall. This is for several reasons. One is because the load would vary across the columns, with much less total response -- those on one side being in tension, on the other in compression, those in the middle not stressed at all -- whereas the north and south walls would all resist in tension and compression, respectively.

A good analogy would be an I-beam. The flanges present maximum resistance to bending in the plane of the webbing, but much less to bending out of plane. Once the south wall is gone, a very large part of the rigidity of the structure is gone with it; in effect, it's half way to the I-beam with an out-of-plane bending moment. This is pretty basic engineering, surely?

Dave

[R.Mackey]

Good analogy, although it's even more so because of the limited ways the floors can respond. But yes, very basic engineering. Which makes it either gross incompetence or a particularly flagrant lie.

[BasqueArch]

This is a lie.

The east and west walls do not resist this torque, any more than they would have resisted a wind load on the north wall. This is for several reasons. One is because the load would vary across the columns, with much less total response -- those on one side being in tension, on the other in compression, those in the middle not stressed at all -- whereas the north and south walls would all resist in tension and compression, respectively. Another is because they couple to the core via those flexible truss structures, and those cannot resist being twisted.

You've been already told this, in this very thread.



Their "not supported by any analysis" and "one big hand-wave" is actually several hundred pages of report, backed by one of the most complex modeling efforts in history.

You lie with practically every post now, Tony. This is usually a sign that you should rethink your conclusions.

Newtons Bit
Yes it will. The centroid of the vertical forces from the remaining 3 walls is no longer concentric with the center of mass of the upper block. And considering the upper block is falling, there is thus rotation. Draw a free-body diagram ffs.


Most of the north wall was also gone as were a sizable portion of stiffening floors, with the rest of the floors fire-weakened.

The moment at top and bottom of the east and west walls columns were opposite and horizontal, in addition to the vertical gravity loads.

[Mangoose]

Removing one wall from a four sided structure will not cause rotation. It is actually the walls which are normal to the overloaded or failed wall which would resist the torque in the direction of that wall. In the case of the North Tower it would have been the east and west walls resisting torque towards the buckled south wall.


And yet reality shows that the walls adjacent to the failed wall did NOT resist the torque as you claim they should have. In the case of WTC2, it would have been the North and South faces "resisting torque" (as you say) towards the buckled East Face, and video documentation shows perimeter columns along the North Face twisted eastward and failed along a line of fracture that progressed westward until it reached the West Face. The columns seen here at the northwest corner were the last to fail, and only at that point was the upper block free to descend vertically.

http://img504.imageshack.us/img504/7572/collapse9.jpg

Notice that there are no bombs exploding or thermite igniting or anything else happening on the North Face other than columns getting overstressed, twisting, and failing.

[BasqueArch]

And yet reality shows that the walls adjacent to the failed wall did NOT resist the torque as you claim they should have. In the case of WTC2, it would have been the North and South faces "resisting torque" (as you say) towards the buckled East Face, and video documentation shows perimeter columns along the North Face twisted eastward and failed along a line of fracture that progressed westward until it reached the West Face. The columns seen here at the northwest corner were the last to fail, and only at that point was the upper block free to descend vertically.

Notice that there are no bombs exploding or thermite igniting or anything else happening on the North Face other than columns getting overstressed, twisting, and failing.

Thanks Mangoose. Another time consuming conclusive irrefutable factual post.
Notice the angle of the top block in relation to the bottom and ask yourself if the 14" x 14" columns landed atop one another or onto the slab below.

ETA:The east wall had slowly buckled in over 3 feet before collapse.
The failed east wall tilt angle and corresponding north wall top block columns angle are parallel throughout the collapse. The columns below the collapse are vertical in this same period. Did the north wall columns buckle or sheared or both. GrizzlyB Post#250 suggests buckled.
---------------------------------------------------------------------------------------------
You can't reason someone out of something they were not reasoned into - Swift

[twinstead]

Nice sequence of pictures. It makes it easy to see that the building began to fail exactly at the point of impact of the plane, pretty much in the manner explained in the generally accepted narrative of events.

[Newtons Bit]

I need to disagree with both Dave Rogers and RMackey here. An I-Beam is an incorrect analogy of how the lateral resisting structure in the WTC behaves.

Here's a quick plan view of the WTC:
http://forums.randi.org/imagehosting/thum_163294ad4cbf40a0cf.gif (http://forums.randi.org/vbimghost.php?do=displayimg&imgid=17848)

The red-arrow is a force applied to the face of a wall. This force is transfered by the diaphragm stiffness to the walls perpendicular to this force. These walls (moment frames, really) are the only elements that significantly resist this lateral force.

For the structure to behave as a wide-flange, as analogized, there would need to be a mechanism in place that could resist the incredibly large shear flow from one side to another. This force is in the weak-axis of the deck (in and out of the plane of my picture). There's absolutely no way a 4" deck handle that. Not even close. Nor are there connections stiff enough to load in that direction if the deck was strong enough.

Mr. Szamboti is correct (mostly) in saying, "It is actually the walls which are normal to the overloaded or failed wall which would resist the torque in the direction of that wall." These walls are built to take forces in this direction. However, again, it is moment, not torque.

The wall will load very similarly to a beam on elastic foundation (elevation view):

http://forums.randi.org/imagehosting/thum_163294ad4ce207f0a8.gif (http://forums.randi.org/vbimghost.php?do=displayimg&imgid=17849)

The red force is the very eccentric resultant compressive force that is redistributed from the failed wall. The green graph is the distribution of stress due to the moment from the eccentric force. From the pictures Mangoose provided, you can see how this stress overloaded these walls.

[Tony Szamboti]

A good analogy would be an I-beam. The flanges present maximum resistance to bending in the plane of the webbing, but much less to bending out of plane. Once the south wall is gone, a very large part of the rigidity of the structure is gone with it; in effect, it's half way to the I-beam with an out-of-plane bending moment. This is pretty basic engineering, surely?

Dave

A channel is probably a better analogy after one wall from a box beam is gone. The channel is still vertically stable. That is why John Skilling could say that one exterior wall and it's corners could be completely removed and the building could still take a 100 mph wind.

Just thought you might like to comment on why your earlier thoughts would not apply to the Oklahoma City federal building and the Khobar barracks, both of which had a wall of the building and a good bit of their interiors blasted off, yet no rotation as it seems you would predict. This is because the remaining channel form is vertically stable.

http://www.truthdig.com/images/reportuploads/oklahomacity_350.jpg


http://www.loc.gov/rr/frd/images/khobar.jpg

The only thing that can cause a torque is an unsupported overhang. In the case of the North Tower the east and west walls along with the north wall corners still supported most of the building and all that should have happened if the south wall failed was local south side floor slab failures, not a rotation of the entire 207 foot per side building.

[Tony Szamboti]

Mr. Szamboti is correct (mostly) in saying, "It is actually the walls which are normal to the overloaded or failed wall which would resist the torque in the direction of that wall." These walls are built to take forces in this direction. However, again, it is moment, not torque.

The wall will load very similarly to a beam on elastic foundation (elevation view):

From the pictures Mangoose provided, you can see how this stress overloaded these walls.

I usually use the term moment in these types of discussions and only referred to a torque in reply to Dave Rogers, since that is the term he used. The correct term here would be moment.

The source you asked for concerning the load redistribution to the east and west walls would be the NIST report. The analysis for WTC 1 does not show enough extra load on these walls to cause their failure.

[Tony Szamboti]

And yet reality shows that the walls adjacent to the failed wall did NOT resist the torque as you claim they should have. In the case of WTC2, it would have been the North and South faces "resisting torque" (as you say) towards the buckled East Face, and video documentation shows perimeter columns along the North Face twisted eastward and failed along a line of fracture that progressed westward until it reached the West Face. The columns seen here at the northwest corner were the last to fail, and only at that point was the upper block free to descend vertically.

http://img504.imageshack.us/img504/7572/collapse9.jpg

Notice that there are no bombs exploding or thermite igniting or anything else happening on the North Face other than columns getting overstressed, twisting, and failing.

I am discussing WTC 1 here. What would be interesting is if you could find a photo of the WTC 1 east or west perimeter walls leaning towards the south while still attached.

[Newtons Bit]

I usually use the term moment in these types of discussions and only referred to a torque in reply to Dave Rogers, since that is the term he used. The correct term here would be moment.

The source you asked for concerning the load redistribution to the east and west walls would be the NIST report. The analysis for WTC 1 does not show enough extra load on these walls to cause their failure.

I was actually looking for a page number as I don't have the report memorized ;)

[Furcifer]

Seems like apples and oranges to me Tony. Two entirely seperate types of buildings, with drastically different load paths. At least they're buildings :rolleyes:

[Grizzly Bear]

A channel is probably a better analogy after one wall from a box beam is gone. The channel is still vertically stable. That is why John Skilling could say that one exterior wall and it's corners could be completely removed and the building could still take a 100 mph wind.

Just thought you might like to comment on why your earlier thoughts would not apply to the Oklahoma City federal building and the Khobar barracks, both of which had a wall of the building and a good bit of their interiors blasted off, yet no rotation as it seems you would predict. This is because the remaining channel form is vertically stable.

http://www.truthdig.com/images/reportuploads/oklahomacity_350.jpg


http://www.loc.gov/rr/frd/images/khobar.jpg

The only thing that can cause a torque is an unsupported overhang. In the case of the North Tower the east and west walls along with the north wall corners still supported most of the building and all that should have happened if the south wall failed was local south side floor slab failures, not a rotation of the entire 207 foot per side building.

A) It was a reinforced concrete building
B) It had a more traditional column grid layout -- the trade centers had all of their load bearing structural elements in the core and along the perimeter.

The concrete frame immediately removes all likelihood for the same structural response, if not the column grid & the height of the building.

[R.Mackey]

I need to disagree with both Dave Rogers and RMackey here. An I-Beam is an incorrect analogy of how the lateral resisting structure in the WTC behaves.

It is a bit more complicated, sure... shear lag rears its ugly head...

Here's a better picture, courtesy NCSTAR1-2A:

http://forums.randi.org/imagehosting/thum_91934ad52ea8a7d80.jpg (http://forums.randi.org/vbimghost.php?do=displayimg&imgid=17857)

This is Figure 5-5 of that report, showing the effect of wind on a Tower perpendicular to one face. All four walls participate, true.

The situation Tony is confusing, however, strikes me as rather different than a uniform wind loading case. A better question is this -- Suppose we sever the core and rotate it in one direction. Which exterior walls respond? This is close to what happened in WTC 1, except before this occurred, one exterior wall buckled, and the opposite wall had a huge hole poked in it. In this case there will be some minor resistance from the east and west walls, and some minor diaphragm stiffness against those walls opposing the gross core motion up top, but this is much less than the response had the north and south walls remained intact.

Regarding his claim about those walls, since he won't give direct cites it's anyone's guess, but I'd start with Figures 4-64 through 4-67 and 4-72 through 4-81 of NCSTAR1-6D. In these, sure, the east and west walls aren't overloaded until after the south wall gives, followed by the core failure, but so what? Total non sequitur.

As is comparison to the Murrah building. Seriously, I'm not bothering with him anymore until he at least tries to make sense.

[Furcifer]

The only thing that can cause a torque is an unsupported overhang. In the case of the North Tower the east and west walls along with the north wall corners still supported most of the building and all that should have happened if the south wall failed was local south side floor slab failures, not a rotation of the entire 207 foot per side building.

So you show two pictures of buildings with utterly no overhang whatsoever?

I think you're trying to say the WTC should have failed in a similar manner, with the damaged side falling down independent of the upper section.

No. No, no no. Nooooo.

That's the first thing you learn when you look at the WTC design. The open areas from the core to the exterior meant no vertical transfer of loads on the damaged side. It would have been shifted to the core in compression and some of the exterior in tension.

I think there's little doubt the damage alone would have resulted in a collapse. It's the fire that sealed the deal.

I find it annoying you keep saying the same things over and over again like repeating them will change the facts. What's up with that? It's such a weird thing to see someone with the capacity not get it after all this time.

[Mangoose]

Notice the angle of the top block in relation to the bottom and ask yourself if the 14" x 14" columns landed atop one another or onto the slab below.


Clearly the slab. And a few North Face perimeter columns adjacent to the northeast corner at Floors 77-79 were STILL standing after the top of the upper block had passed below:

http://img26.imageshack.us/img26/4392/b23b.gif

This section of the outer wall stood for a few seconds after it became visible through the dust as it leaned to the west and then fell. So the descending upper block missed this portion of the outer walls.

I am discussing WTC 1 here. What would be interesting is if you could find a photo of the WTC 1 east or west perimeter walls leaning towards the south while still attached.


Since you are arguing that such a scenario is physically impossible, it is absolutely relevant to point out that the same thing played out in the twin building of WTC1, where better quality images exist. And of course the tilting scenario that NIST described pertained to both WTC1 and WTC2.

And you should know that there are no quality images of the East Face of WTC1 during the collapse on account of the evacuation of lower Manhattan (eliminating potential photographers) and the lingering dust in the air from the collapse of WTC2 and smoke trails from fires on the North Face. There are no available images I've seen of the West Face at the quality we have with the North Face of WTC2. There is a reason why almost every collapse video or photo we have of WTC1 is from the north.

Regardless of this, I have already shown you video from the northeast that shows the tilting of the upper block of WTC1 prior to any collapse on the North Face.

[Tony Szamboti]

I was actually looking for a page number as I don't have the report memorized ;)

The additional load increases on the east and west walls in WTC 1 due to core unloading and south wall buckling are given as a percentage of original load, in different places in NCSTAR 1-6. They mention all of the additional loads in a summary on pages 313 and 314 of NCSTAR 1-6D.

They amount to a 62% increase due to the core and south wall and there was also a load increase of 7% due to the damage to the north wall for a total load increase on the east and west walls of 69%.

If the load on the east and west walls was then 1.69 times their original gravity load and they were capable of taking 5.00 times their original gravity load, I don't see why they would fail. I think the only answer is a complete core failure and that they were pulled inward and buckled.

[dio]

You assume that the overload was evenly distributed across all the columns of the east and west walls. With a softened and buckled core, that was not the case.

That second pic of Newtons Bit is revealing.

The columns of the east and west walls failed progressively*, starting from the failed south wall. Of course this "progression", once started, was extremely fast.

*and therefore the tilt of the upper block.

[GlennB]

If the load on the east and west walls was then 1.69 times their original gravity load and they were capable of taking 5.00 times their original gravity load, I don't see why they would fail. I think the only answer is a complete core failure and that they were pulled inward and buckled.

So, back to the question you have ignored three times already. If - according to you - the bowing was caused by CD of the core, why did the bowing last so damn long?

[TruthersLie]

A channel is probably a better analogy after one wall from a box beam is gone. The channel is still vertically stable. That is why John Skilling could say that one exterior wall and it's corners could be completely removed and the building could still take a 100 mph wind.

Just thought you might like to comment on why your earlier thoughts would not apply to the Oklahoma City federal building and the Khobar barracks, both of which had a wall of the building and a good bit of their interiors blasted off, yet no rotation as it seems you would predict. This is because the remaining channel form is vertically stable.

http://www.truthdig.com/images/reportuploads/oklahomacity_350.jpg


http://www.loc.gov/rr/frd/images/khobar.jpg

The only thing that can cause a torque is an unsupported overhang. In the case of the North Tower the east and west walls along with the north wall corners still supported most of the building and all that should have happened if the south wall failed was local south side floor slab failures, not a rotation of the entire 207 foot per side building.

I'm not an engineer... I have taken engineering courses... but are you really trying to compare the Murrah building and the other buidling to the towers? Really?

You are supposed to be an engineer, yet you are comparing apples to carbon nanotubes... they are not applicable, nor can you compare them...

wowsers.. please remind me of what you have engineered, I really never want to be near them, or use anything you may have ever designed if you can't possibly notice the differences....

[Mangoose]

Okay, I just examined the four best WTC1 collapse videos that show activity on all four faces, and I was able to synchronize them in Premiere on the basis of common events, which allowed me to put together this tentative chronology of the first three seconds of the collapse (with even more tentative interpretations):

0;00: visibility of external fires on the East Face on Floors 98-100 rapidly spread southward to the South Face (Interpretation: possibly the moment the bowed columns on the South Face on Floors 96-97 initially buckle)

0;25: large quantity of fire on the South Face in the area of the bowed columns on Floors 98-100 is expelled outside the building (Interpretation: possibly a result of the localized floor collapse on the South Face)

1;05: antenna mast begins to descend and tilt in the direction towards the area of bowed columns on the South Face (Interpretation: the localized collapse now includes the core columns on Floors 96-97)

1;18: a dust cloud exits the East Face at the southeast corner on the 95th and 96th Floors (Interpretation: this is an expansion of the local collapse on the East Face)

1;22: fires on the East Face on Floors 98-100 (near the center of the Face) begin to descend (Interpretation: The 96th and 97th Floors begin to collapse on the East Face; the North Face does not yet show any signs of structural failure)

1;24: first movement of columns 145-150 on the 95th and 96th Floors on the North Face (Interpretation: The failure progression has now finally reached the North Face)

1;29: smoke or dust cloud exits the West Face near the northwest corner on the 100th Floor

2;00: a dust cloud emerges from the 95th and 96th Floors on the North Face at columns 145-150; fires at the southwest corner on the 96th Floor intensify; the large fiery debris cloud on the South Face at the area of the bowing columns descends two floors (Interpretation: The North Face is now involved in the collapse; all perimeter columns on the impact floors are buckling or shifting, other than a small section of perimeter columns on the west end of the North Face which remains stationary)

2;01: the North Face roofline starts to descend (Interpretation: The new collapse on the North Face precipitates the descent of the roof.)

2;05: North Face columns below the impact hole (110-135) on Floors 92-97 begin to lean; floor collapse occurs at Floor 97-98 between columns 101-110 (Interpretation: The upper block begins to compress a little).

2;09: dust clouds exit the 98th Floor simultaneously on the North and West Faces, a dust jet exits the West Face at the 104th Floor, and a fiery debris cloud exits the East Face near the southeast corner (Interpretation: The northern portion of the upper block compresses a little while the southern portion precipitates collapse to lower floors at the southeast corner)

2;24: 92nd Floor fires on the West Face flame outside the building (Interpretation: The 92nd Floor on the South Face is possibly now involved in the collapse)

3;02; 92nd Floor fires on the North Face flame outside the building; on the South Face a dust cloud exits the building on the 92nd Floor; the fiery debris cloud on the South Face at the southeast corner descends to the 96th Floor, the fires originally at Floors 98-100 on the East Face now descend to the 96th Floor (Interpretation: the descending fires on the East and South Faces is indicative of a falling and crushing upper block which has now reached the 92nd Floor)

[Scott_Milner]

Who says that any columns melted?

Melted..."softened'...whatever. Insert technical term >here<.

So you do believe there was "tilting"?

It's not what i believe, it is what is apparent in the video evidence. It happened.

#1. What does "core columns and perimeter columns were connected and could not have caused a rotation" mean exactly? How do the columns "cause" a rotation?

The massive core columns, and perimeter columns connected the sections above and below the impact area. Only a small percentage of columns were damaged. The upper section cannot begin to "rotate" while these columns remain intact.

#2. So you are saying there is no "rotation" but there is "tilting".....what exactly is "tilting" and how is it different from "rotation"?

Tilting = leaning to one side. Pivoting.

Rotation - the upper block became disconnected from all of the core and perimeter columns and then began to 'spin' end to end while balancing itself over the remainder of the tower.

The very columns which prevented crushing, and forced the upper floors to begin tipping suddenly "gave way"? How does this happen when the loading becomes asymmetrical, yet all columns on every side of the tower begin ejecting in all directions? The theories of some on here at fantasy at best and cannot explain the problems I've addressed in this post, nor do these 'rotation' theories follow any video evidence.

[Tony Szamboti]

I'm not an engineer... I have taken engineering courses... but are you really trying to compare the Murrah building and the other buidling to the towers? Really?

You are supposed to be an engineer, yet you are comparing apples to carbon nanotubes... they are not applicable, nor can you compare them...

wowsers.. please remind me of what you have engineered, I really never want to be near them, or use anything you may have ever designed if you can't possibly notice the differences....

Instead of just making a lot of noise why don't you actually explain why the Murrah building and the Khobar barracks building did not begin to rotate after completely losing a wall and a significant portion of their interior. Then you should explain why you don't think it would apply to WTC 1.

[Hokulele]

Melted..."softened'...whatever. Insert technical term >here<.


Softened?

[NutCracker]

Instead of just making a lot of noise why don't you actually explain why the Murrah building and the Khobar barracks building did not begin to rotate after completely losing a wall and a significant portion of their interior. Then you should explain why you don't think it would apply to WTC 1.

Classic burden of proof shift attempt noted. As the Murrah building is of an entirely different design YOU need to show how the behaviour of the Murrah building applies to WTC 1.

[BasqueArch]

Tony Szamboti
I am discussing WTC 1 here. What would be interesting is if you could find a photo of the WTC 1 east or west perimeter walls leaning towards the south while still attached.

Wrong #6 - Video evidence of WTC2 gravity only collapse is conclusive. All the video evidence of WTC1 confirms the gravity only collapse. There is less video taken of WTC1.
This is why TS wants to concentrate on WTC1. He has more hiding room to ping pong this hypothetical/theoretical discussion indefinitely.

Latest ping-pong below.

Tony Szamboti
The additional load increases on the east and west walls in WTC 1 due to core unloading and south wall buckling are given as a percentage of original load, in different places in NCSTAR 1-6. They mention all of the additional loads in a summary on pages 313 and 314 of NCSTAR 1-6D.

They amount to a 62% increase due to the core and south wall and there was also a load increase of 7% due to the damage to the north wall for a total load increase on the east and west walls of 69%.

If the load on the east and west walls was then 1.69 times their original gravity load and they were capable of taking 5.00 times their original gravity load, I don't see why they would fail. I think the only answer is a complete core failure and that they were pulled inward and buckled.


If “…the only answer is a complete core failure and that they were pulled inward and buckled” then:

1) The perimeter columns would be pulled inward by the attached floors, they would not have toppled outward in all 4 directions and landed hundreds of feet away without floors attached to them.

2) This would contradict the visual evidence of the perimeter columns at failed floors slowly creep buckling for 10-20 minutes before collapse, not suddenly buckling.. GlennB has been chasing TS on this for weeks.

3) This would contradict the core columns TS claimed to have been demoed every 3 stories of WTC1 survived for 60 stories, WTC2 for 40 stories after floors total collapse.

4) WTC1,2 . All four sides of the perimeter walls would have dropped at the same time, top block would not have tilted toward initial failed wall.

Watch TS reply with more numerical blah blah.

================================================== ====

You can’t reason someone out of something they were not reasoned into – Swift

[Tony Szamboti]

Classic burden of proof shift attempt noted. As the Murrah building is of an entirely different design YOU need to show how the behaviour of the Murrah building applies to WTC 1.

I did. The channel shape is still vertically stable so removing one wall from a four sided structure will not cause a rotation.

[Tony Szamboti]

You assume that the overload was evenly distributed across all the columns of the east and west walls. With a softened and buckled core, that was not the case.

That second pic of Newtons Bit is revealing.

The columns of the east and west walls failed progressively*, starting from the failed south wall. Of course this "progression", once started, was extremely fast.

*and therefore the tilt of the upper block.

Why didn't this happen to the Murrah and Khobar barracks buildings after they lost a wall and much of their interior?

[twinstead]

Why didn't this happen to the Murrah and Khobar barracks buildings after they lost a wall and much of their interior?

Do you think the way a building is constructed has anything to do with the way it reacts to damage and fire?

[NutCracker]

I did. The channel shape is still vertically stable so removing one wall from a four sided structure will not cause a rotation.

I see. Because the "channel shape" in building A, of design D with damage P is still vertically stable, the "channel shape" in building B of design E with damage Q is also still vertically stable.

You need to show that this implication holds. Merely claiming so doesn't do.

But wait, since the video evidence does show a tilt in the case B=WTC and Q=airliner impact,resulting fires we can conclude the above is false. So you can save yourself some time futally attempting to prove the above.

[Grizzly Bear]

Instead of just making a lot of noise why don't you actually explain why the Murrah building and the Khobar barracks building did not begin to rotate after completely losing a wall and a significant portion of their interior. Then you should explain why you don't think it would apply to WTC 1.

Gee... I really didn't think I'd have to draw it out for you. What do you think is different between the Murrah building and the WTC? Why does it fail to compare to the towers? I gave two reasons earlier that you obviously didn't see.

Could this be one?
http://img117.imageshack.us/img117/9484/wtcplan.jpg

vs

http://img2.imageshack.us/img2/4383/001fct.th.jpg (http://img2.imageshack.us/i/001fct.jpg/)

One is steel framed with a core containing all of the MEP equipment and structure which collectively carries approximately half the gravitational loads of the building. The other, is of reinforced concrete, and whose struture is organized along a grid.

Why don't you tell ME the difference? Obviously you seem to have some insight that I don't, I'd like to know; seriously.

Why do you think that even if we added fires to the Murrah Building it would still fail to model the trade centers? Another serious question.

Because you appear oblivious to some obvious characteristics which contrast the two.

[TruthersLie]

Just like a twoof. Your lack of vocabulary and understanding of how the idea of MELTED and SOFTENED are rather telling

Melted..."softened'...whatever. Insert technical term >here<.


They are VASTLY different. Think of ice cubes... melted is water


It's not what i believe, it is what is apparent in the video evidence. It happened.


then it should be easy for you to find one of dozens of if not hundreds of peer reviewed engineering journals which agree with you. Find just one.

[TruthersLie]

Instead of just making a lot of noise why don't you actually explain why the Murrah building and the Khobar barracks building did not begin to rotate after completely losing a wall and a significant portion of their interior. Then you should explain why you don't think it would apply to WTC 1.

I thought it was very apparent.

the two PISS poor examples you quote are traditional designs with floor supports and interior bracing which hold up the floors.

wtc towers were NOT that design. dur...

absolutely amazing that you are a engineer.... wowsers.

[funk de fino]

Instead of just making a lot of noise why don't you actually explain why the Murrah building and the Khobar barracks building did not begin to rotate after completely losing a wall and a significant portion of their interior. Then you should explain why you don't think it would apply to WTC 1.

What a completely ignorant post. You'll be comparing the WTC towers to dog kennels blown over in the wind next.

[Mangoose]

The very columns which prevented crushing, and forced the upper floors to begin tipping suddenly "gave way"? How does this happen when the loading becomes asymmetrical, yet all columns on every side of the tower begin ejecting in all directions?


The columns "on every side of the tower" did not give way and eject material in all directions at the same time. This happened gradually as the photos on the previous page show. The tipping increased and gained momentum as more and more columns further away from the collapsed face failed until the face opposite underwent collapse.

[Mangoose]

Here is the original animation again. It represents the tilting of the upper block prior to the North Face collapses at approx. 2;05 and 2;09.

http://img405.imageshack.us/img405/2857/aniv.gif

Three features reveal the tilt: (1) the line of fires on Floors 98-100 on the East Face descends a story or two, particularly the portion closest to the South Face, (2) the antenna mast tilts to the south, (3) the northwest edge of the building along the upper block leans in the same direction of the antenna mast, while an outward bulge appears around Floors 95-98.

[Edx]

Melted..."softened'...whatever. Insert technical term >here<.

Melted isnt the same as weakened. Its okay, I know you want to strawman the reality because it makes it easier to imagine its ridiculous.

How does this happen when the loading becomes asymmetrical, yet all columns on every side of the tower begin ejecting in all directions?

As we've seen from French demolitions without explosives, the upper part of a building crushing the lower part will result in debris being pushed out from the sides.

But I also want to know where these explosion sounds are from these explosives that you say flung steel beams around?

[GlennB]

But I also want to know where these explosion sounds are from these explosives that you say flung steel beams around?

For him to answer that truthfully would require him to face his delusions, head on, and recognise them.
Don't hold your breath.

[A W Smith]

Here is the original animation again. It represents the tilting of the upper block prior to the North Face collapses at approx. 2;05 and 2;09.

http://img405.imageshack.us/img405/2857/aniv.gif

Three features reveal the tilt: (1) the line of fires on Floors 98-100 on the East Face descends a story or two, particularly the portion closest to the South Face, (2) the antenna mast tilts to the south, (3) the northwest edge of the building along the upper block leans in the same direction of the antenna mast, while an outward bulge appears around Floors 95-98.


Why that appears to be the eastern view which Szamboti was hoping you didn't have. Not Fair!:eek:

[Audible Click]

Why that appears to be the eastern view which Szamboti was hoping you didn't have. Not Fair!:eek:

It's just not fair that skeptics can do research and twoofers have limited Googlefu!

[Mangoose]

Here is the moment when the columns on the North Face began to fail:

http://img203.imageshack.us/img203/6802/94646677.gif

We can see that columns 146-150 on the 94th Floor, damaged by the impact of AA11, lean to the left. This is visually most obvious with column 150. On the 95th Floor, we can see the same columns 147-150 (covered with aluminum cladding) lean likewise. The more damaged columns 144-146, two of which are severed by AA11's wings on the 94th Floor, simply snap. Columns 135-143, which hang unsupported over the impact hole, begin to descend as well.

This was a full second after a fiery debris cloud was seen forming on the South Face in the area of the bowed columns (on the basis of synchronisms of events on the West Face, visible in both videos).

[BasqueArch]

Here is the moment when the columns on the North Face began to fail:

http://img203.imageshack.us/img203/6802/94646677.gif

Ok.
Still not convinced.
What would be interesting is if you could find a video of the WTC 1 east or west core walls leaning towards the south while still attached.

Yes from the inside.

[Mangoose]

What would be interesting is if you could find a video of the WTC 1 east or west core walls leaning towards the south while still attached.


Okay, here's the video:

ETA: I was about to rickroll you but then thought that that's about as old and lame as the 911Mysteries-type claims made in this thread. So have a lolcat instead, and may you carry it in good health.

http://img508.imageshack.us/img508/9290/pwn3d112841429242730250.jpg

[BasqueArch]

Okay, here's the video:

ETA: I was about to rickroll you but then thought that that's about as old and lame as the 911Mysteries-type claims made in this thread. So have a lolcat instead, and may you carry it in good health.

Thanks Mangoose.

Video Released to Public.
JREF Investigators' Patient Shadowing of Engineer Rewarded.
Twin Towers' Missing Jolts Discovered Behind Szamboti's Basement False Bookcase Moist Doors.

http://www.youtube.com/watch?v=wGTczL2ehLg&feature=related

[Dave Rogers]

Just thought you might like to comment on why your earlier thoughts would not apply to the Oklahoma City federal building and the Khobar barracks, both of which had a wall of the building and a good bit of their interiors blasted off, yet no rotation as it seems you would predict.

Radically different structures react in different ways. In these two cases, there was a partial collapse of the structure above the wall that was destroyed. I note that these two buildings appear to have been concrete framed, and, as most engineers realise, the relative strengths of concrete in tension and compression are very different to those of steel. Could it be that the tensile strength of the concrete in these buildings was lower, in comparison to their compressive strength, which allowed lateral walls to fail in tension and hence for the unsupported part to fall off?

Anyway, it's absurd to say that "the remaining channel form is stable"; this is a classic example of the sweeping statements you like to make without any analysis to back them up. A channel is necessarily weaker against buckling than a box column with the same dimensions, simply because one quarter of it has been removed. You're simply guessing that the remaining three walls of WTC1 were strong enough to resist the loads.

If the load on the east and west walls was then 1.69 times their original gravity load and they were capable of taking 5.00 times their original gravity load, I don't see why they would fail. I think the only answer is a complete core failure and that they were pulled inward and buckled.

Since that suggests that you more or less agree with the NIST collapse scenario (core columns unloaded through the hat truss, then perimeter columns were pulled inwards by sagging floor joists and buckled), why are you even talking about this?

Dave

[TruthersLie]

I did. The channel shape is still vertically stable so removing one wall from a four sided structure will not cause a rotation.

What is next with the bad analogies tony?

are you going to point to the cctv tower fire next? Or some other bad analogy?

really?

[cmcaulif]

Remove three of the four walls of the box beam and you get a plate. With a fixed base this is also has the potential to be vertically stable.

Without knowing the loads and slenderness of the box beam or plate or channel, there is no point in talking about stability.

However, calculate the resultant load on a vertical channel fixed at the base, subjected to body force, and you will see there is always eccentricity, creating a moment.

[rwguinn]

Remove three of the four walls of the box beam and you get a plate. With a fixed base this is also has the potential to be vertically stable.

Without knowing the loads and slenderness of the box beam or plate or channel, there is no point in talking about stability.

However, calculate the resultant load on a vertical channel fixed at the base, subjected to body force, and you will see there is always eccentricity, creating a moment.
Absolutely. Take a look at the location of the Neutral axis or shear center while you're at it...
Take a box beam, under limit (design) load. Replace 5% of the box with a channel (same depth, same thickness), at about 2/3 the overall length. recalculate the allowable loads.
It will probably survive, at room temperature. Now add temperatures of 500-1000 C.

I HATE open sections...

[Dave Rogers]

I need to disagree with both Dave Rogers and RMackey here. An I-Beam is an incorrect analogy of how the lateral resisting structure in the WTC behaves.

I see what you mean about the effect of the moment frame, and you're right that an I-beam isn't as good an analogy as I thought. One point, though; it seems to me that the moment frame will resist shear deformation of the structure, but a shear deformation won't actually involve a rotation of the structure above the shear. The rectangular elements of the structure deform as parallelograms, so any horizontal elements remain horizontal. If a turning moment, as opposed to a lateral force, were applied to the upper block, then this would result in compression of one and tension of the other of the two walls parallel to the axis of the moment. In this case these would be the north and south walls respectively. Removal of the north wall, it seems to me, must cause a much greater degradation of the structure's ability to resist this moment than removal of the east or west wall.

I think that's probably the same thing as R. Mackey said earlier.

Dave

[Tony Szamboti]

Radically different structures react in different ways. In these two cases, there was a partial collapse of the structure above the wall that was destroyed. I note that these two buildings appear to have been concrete framed, and, as most engineers realise, the relative strengths of concrete in tension and compression are very different to those of steel. Could it be that the tensile strength of the concrete in these buildings was lower, in comparison to their compressive strength, which allowed lateral walls to fail in tension and hence for the unsupported part to fall off?

When the one wall falls off a moment is generated which causes a relaxation of some of the load on the parallel wall and an increase in load on the perpendicular walls towards the side of the failed wall.


Anyway, it's absurd to say that "the remaining channel form is stable"; this is a classic example of the sweeping statements you like to make without any analysis to back them up. A channel is necessarily weaker against buckling than a box column with the same dimensions, simply because one quarter of it has been removed. You're simply guessing that the remaining three walls of WTC1 were strong enough to resist the loads.

A channel with equal length sides is nearly as strong against buckling as a box with those same side dimensions, in the direction of the two remaining perpendicular walls, since it is these perpendicular walls that generate over 95% of the moment of inertia in that direction whether it is a channel or box. I can show you the calculations for this if you don't understand.

I am not guessing about anything here. We know what the strength of the perimeter columns was and the increase in the loads found by the NIST in their scenario do not support failure of the east and west walls, and remaining north wall.


Since that suggests that you more or less agree with the NIST collapse scenario (core columns unloaded through the hat truss, then perimeter columns were pulled inwards by sagging floor joists and buckled), why are you even talking about this?
No, I am saying the NIST scenario does not produce the necessary stress to cause the failure of the east and west walls and remaining north wall.

Some of the more imaginative individuals on this forum seem to think the overload on the east and west walls were non uniform enough to cause a failure of columns at the south sides of the east and west walls, but they provide no basis to show loads which would have been sufficient to cause failure and the NIST calculations do not either.

[beachnut]

Why didn't this happen to the Murrah and Khobar barracks buildings after they lost a wall and much of their interior?
You continue to prove you are not a structural engineer and push your failed explosives, your real-cd-deal. How does an engineer become a paranoid conspiracy theorist like you have? In your delusion is it Cheney who did it, or some diabolical military industrial complex CEO? Your inability to understand the difference of OKC, Saudi Arabia and the WTC are enough proof you lack the skills required to understand you are wrong. In addition your jolt work is hilarious as you use video that would not show a jolt anyway. If only you had taken some sampling theory. It comes back to the basics. Why are you unable to present cogent work to prove your ideas?

[Tony Szamboti]

You continue to prove you are not a structural engineer and push your failed explosives, your real-cd-deal. How does an engineer become a paranoid conspiracy theorist like you have? In your delusion is it Cheney who did it, or some diabolical military industrial complex CEO? Your inability to understand the difference of OKC, Saudi Arabia and the WTC are enough proof you lack the skills required to understand you are wrong. In addition your jolt work is hilarious as you use video that would not show a jolt anyway. If only you had taken some sampling theory. It comes back to the basics. Why are you unable to present cogent work to prove your ideas?

What is actually cogent here is your inability to provide any details for your position and where I am wrong.

Why do you rant without any discussion of details?

[beachnut]

What is actually cogent here is your inability to provide any details for your position and where I am wrong.

Why do you rant without any discussion of details?
Prove explosives were used. Simple! Present your evidence for explosives or thermite. You can't. Your failure is 8 years old. You have less evidence for your delusional claims than Bigfoot believers have for Bigfoot. Sad delusions sparked by paranoid conspiracy minded fools have mislead you.

Your jolt work is hilarious when you used low resolution and low fps video.

[Tony Szamboti]

Your jolt work is hilarious when you used low resolution and low fps video.

All you are showing here, with this comment you continue to make, is your own ignorance. It is apparent that you did not understand what was said in The Missing Jolt paper.

The actual jolt would not be visible, since it occurs over a very short time frame. However, what can be discerned is whether there was a velocity loss commensurate with the energy required to collapse just the first set of columns on either side of the first collision. There is no velocity loss at all and in fact there is a continuous velocity gain. Thus there could not have been a jolt, which is the only natural mechanism which could have transferred the necessary energy but with a resulting velocity loss.

You see when momentum is transferred kinetic energy and velocity is lost. It is this lack of velocity loss which shows the upper block in WTC 1 was not doing the required work to collapse the structure.

[R.Mackey]

Like a broken record, Tony.

[Tony Szamboti]

Like a broken record, Tony.

Sounds like sour grapes since you can't refute the fact that an impulse was required and is not observed since there was no velocity loss.

[funk de fino]

Sounds like sour grapes since you can't refute the fact that an impulse was required and is not observed since there was no velocity loss.

Swallow your pride be a man and admit your failure and lies. We can all see the tilt when you say there is none. We all know you never saw a video where Silverstein admitted it was a CD for safety reasons.

All your other stuff is bluster to paper over these Grand Canyons in your credibility.

You say someone cannot use low res video for analysis and then support your junk with low res video. What a hoot!

[Dave Rogers]

Sounds like sour grapes since you can't refute the fact that an impulse was required and is not observed since there was no velocity loss.

When you repeatedly display an inability to grasp the concept of subtraction, it's hard to know what sort of refutation you would understand.

Dave

[NutCracker]

All you are showing here, with this comment you continue to make, is your own ignorance. It is apparent that you did not understand what was said in The Missing Jolt paper.

The actual jolt would not be visible, since it occurs over a very short time frame. However, what can be discerned is whether there was a velocity loss commensurate with the energy required to collapse just the first set of columns on either side of the first collision. There is no velocity loss at all and in fact there is a continuous velocity gain. Thus there could not have been a jolt, which is the only natural mechanism which could have transferred the necessary energy but with a resulting velocity loss.

You see when momentum is transferred kinetic energy and velocity is lost. It is this lack of velocity loss which shows the upper block in WTC 1 was not doing the required work to collapse the structure.

Cut the BS crap, Szamboti. You have shown time and time again where you are wrong, where your reasoning fails. Time and time again you have been shown why your jolt paper is an insult to the backside even as toliet paper.

Recycling your drivel does not convince anyone except the delusional contents of your skull.

Just cut it. Ok? Thank you.

[TruthersLie]

What is actually cogent here is your inability to provide any details for your position and where I am wrong.

Why do you rant without any discussion of details?

Still waiting for you to explain how your examples have any ANY connnection to the WTC towers.

Please provide ANY connection between them.

I (and everyone else) can see that they are VASTLY different designs, which will react differently... (and that isn't even going on about how they are vastly different construction materials). Yet you bring them up...

Again and again, I just want to see a peer reviewed engineering journal article... you claim to be an engineer (shudder), so you should be able to pass muster at ANY engineering journal... why can't you get into one?

After 8 years you (and your twoop) should be able to pass out dozens of peer reviewed engineering journal articles... yet you have ONE (which wasn't a peer reviewed article just a reply to bazant, which was completely demolished).

Come on tony... at least make it to the minor leagues.

[TruthersLie]

All you are showing here, with this comment you continue to make, is your own ignorance. It is apparent that you did not understand what was said in The Missing Jolt paper.

The actual jolt would not be visible, since it occurs over a very short time frame. However, what can be discerned is whether there was a velocity loss commensurate with the energy required to collapse just the first set of columns on either side of the first collision. There is no velocity loss at all and in fact there is a continuous velocity gain. Thus there could not have been a jolt, which is the only natural mechanism which could have transferred the necessary energy but with a resulting velocity loss.

You see when momentum is transferred kinetic energy and velocity is lost. It is this lack of velocity loss which shows the upper block in WTC 1 was not doing the required work to collapse the structure.

wow...
trying that broken record trick tony?

You post at Today, 11:07 AM , get a reply 11:08 am by ryan mackey and then go back and EDIT your orignial post AFTER they have replied Last edited by Tony Szamboti; Today at 11:21 AM.

That is wonderful intellectual cowardice.

What kind of chicken **** bs is that?

[dafydd]

Does Tony have any engineering qualifications?

[Grizzly Bear]

Does Tony have any engineering qualifications?

IIRC he's a Mechanical Engineer.

[Grizzly Bear]

When the one wall falls off a moment is generated which causes a relaxation of some of the load on the parallel wall and an increase in load on the perpendicular walls towards the side of the failed wall.


A channel with equal length sides is nearly as strong against buckling as a box with those same side dimensions, in the direction of the two remaining perpendicular walls, since it is these perpendicular walls that generate over 95% of the moment of inertia in that direction whether it is a channel or box. I can show you the calculations for this if you don't understand.

You seem to be forgetting already after being reminded that the Murrah building had an interior column system arranged to a grid. The maximum beam spans were therefore relatively short and the loads were therefore redistributed much differently than was possible in the trade centers. Has this registered yet?

[BasqueArch]

Originally Posted by dafydd
Does Tony have any engineering qualifications?

IIRC he's a Mechanical Engineer.

According to AE911truth website, Tony Szamboti is a degreed only mechanical engineer graduate, not licensed P.E. His bio describes him as a “Mechanical Engineer.”

From American Society of Mechanical Engineers web site:

“Who needs to take the Exam
The following people must have a PE license to practice:
- Anyone who offers engineering services to the public
- Anyone who advertises one's self as an "Engineer"
- Half of the principals (owners) of a company that offers engineering services to the public
- Half of the principals of a company that wants to use the term "Engineer" in its name.”

http://studentsections.asme.org/ucsb/test.html

TS’s postings here are evidence that he cannot provide a valid CD explanation for the collapse of the Twin Towers, chooses not to understand that the visual record provides both the evidence for a gravity-only collapse and falsifies a CD explanation, and that half of all mechanical engineering graduates are below average.

[TruthersLie]

According to AE911truth website, Tony Szamboti is a degreed only mechanical engineer graduate, not licensed P.E. His bio describes him as a “Mechanical Engineer.”

From American Society of Mechanical Engineers web site:

“Who needs to take the Exam
The following people must have a PE license to practice:
- Anyone who offers engineering services to the public
- Anyone who advertises one's self as an "Engineer"
- Half of the principals (owners) of a company that offers engineering services to the public
- Half of the principals of a company that wants to use the term "Engineer" in its name.”

http://studentsections.asme.org/ucsb/test.html

TS’s postings here are evidence that he cannot provide a valid CD explanation for the collapse of the Twin Towers, chooses not to understand that the visual record provides both the evidence for a gravity-only collapse and falsifies a CD explanation, and that half of all mechanical engineering graduates are below average.

wow... That is rather funny.

Is he an ASME member, and do they know that he is advertising himself as an "engineer" even though he has not passed the PE? Hmmmmm....

[cmcaulif]

A channel with equal length sides is nearly as strong against buckling as a box with those same side dimensions, in the direction of the two remaining perpendicular walls, since it is these perpendicular walls that generate over 95% of the moment of inertia in that direction whether it is a channel or box. I can show you the calculations for this if you don't understand.


Does this calculation take into account the fact that stability is dependent on material properties, section geometry, and loading conditions?

How does the buckling strength of a box loaded symmetrically compare even to a larger channel loaded asymmetrically?

[R.Mackey]

I'd give Tony a break on not having his P.E., since it's only required if you go into business for yourself, etc. I don't have a P.E. either.

However, he provides us a sterling example of why arguments to authority are worthless.

[rwguinn]

I'd give Tony a break on not having his P.E., since it's only required if you go into business for yourself, etc. I don't have a P.E. either.

However, he provides us a sterling example of why arguments to authority are worthless.
Having a PE is not necessary to be an engineer. Most companies call their employees who have engineering degrees "Engineer" or a variant of that. It is necessary if you consult as an individual, or sign drawings that require a PE.
I do have a PE, but I didn't go for it until I had been working in the field for over 20 years. Not necessary if you work for a big company.

[BasqueArch]

* cough *

Gravy Vindicated , Szamboti Not

From American Society of Mechanical Engineers web site:

The following people must have a PE license to practice:
- Anyone who offers engineering services to the public
- Anyone who advertises one's self as an "Engineer"

[quote]Originally Posted by Gravy View Post
Fourth time, realcd: are you going to contact the people who can answer your question? You have twice agreed that you should do so.

Will you begin that process now? Yes or no?

Second time: should the U.S. government have mounted an extensive investigation into the Space Shuttle conspiracy claims?

Second time: what would your physical model and tests comprise?

And I was correct that you lied about being a mechanical engineer, wasn't I?

Posted by Tony Szamboti
<snip>

First, I am a mechanical engineer and you are the one who would not be telling the truth by saying I wasn't. <snip>

ETA:
Post by Gravy
And I say you aren't. You can prove me wrong and elicit my apology by forwarding your credentials to me at nyctours@gmail.com. I promise not to share the information with anyone, but I will publlicly apologize for calling you a liar, which I'm certain you are. Hey, I could be wrong: Judy Wood is a mechanical engineer.

Prove it.


http://forums.randi.org/showthread.php?postid=2659689#post2659689

Posted by Tony Szamboti .. I happen to be a mechanical engineer and work with more than what you can count on one hand who think the official story is bogus. I really have had enough here. The official story is obvious BS, they took those towers down to get us to support wars for oil and anyone with half a brain who has looked at it has to know that ... .

ETC.

[BasqueArch]

Having a PE is not necessary to be an engineer. Most companies call their employees who have engineering degrees "Engineer" or a variant of that. It is necessary if you consult as an individual, or sign drawings that require a PE.
I do have a PE, but I didn't go for it until I had been working in the field for over 20 years. Not necessary if you work for a big company.

I agree.

In the 70s you could still take the test in my state for Licensed Architect if you were a draftsman working under an Architect for 12 years. No need to have a BArch. That went in the 80s.

(Why, in my day we had to smash oxygen and hydrogen atoms together to make water)

I guess my point was missed. You can only call yourself an "engineer" if you are licensed. As in medicine, you can be a medical school graduate but can only call yourself a "doctor" if you are licensed. Same for attorneys, etc.

TS lied , and still does, confusing people by calling himself "mechanical engineer" and he knew it and knows it.

TS is fluffing his honorific.
Not a pretty sight.

[Newtons Bit]

I agree.

In the 70s you could still take the test in my state for Licensed Architect if you were a draftsman working under an Architect for 12 years. No need to have a BArch. That went in the 80s.

(Why, in my day we had to smash oxygen and hydrogen atoms together to make water)

I guess my point was missed. You can only call yourself an "engineer" if you are licensed. As in medicine, you can be a medical school graduate but can only call yourself a "doctor" if you are licensed. Same for attorneys, etc.

TS lied , and still does, confusing people by calling himself "mechanical engineer" and he knew it and knows it.

TS is fluffing his honorific.
Not a pretty sight.

This is not true. It depends on the state, as different states have different rules on what you can call yourself. In my state, one does not have to be licensed to refer to themselves as an engineer. You cannot call yourself a professional engineer until after you are licensed by the state.

You can call yourself a mechanical engineer, a structural engineer, a civil engineer, or even a sanitation engineer (what garbage collectors are called here). The only honorific that I know of that is actually illegal to use without a license is Architect.

[dafydd]

How many buildings has Tony designed?

[Hokulele]

How many buildings has Tony designed?


I don't think that really matters. His calculations have been shown to be wrong (repeatedly) on some very basic principles, and his experience or lack thereof really don't add anything to this particular argument.

Anyone with a basic understanding of physics can see where his claim goes off the rails, and various people have provided that basic background for those who haven't studied this elsewhere.

[beachnut]

Sounds like sour grapes since you can't refute the fact that an impulse was required and is not observed since there was no velocity loss.
Tony where is your Pulitzer Prize for the real-cd-deal?

The video still lacks the resolutions to observe velocity changes, and in a model you would have definite velocity ripples which in real life would be masked by the chaos of a gravity collapse; as always it is interesting to note gravity is the primary energy in all CDs make your real-cd-deal ironic and the delusion of an engineer who can't build high rise buildings or understand real cd. It is funny the average velocities you observe are in-line with a gravity collapse. You proved a gravity collapse in your failed paper and have no idea how to turn your failure into the knowledge of reality. If not for the Internet you would be a lone paranoid conspiracy theorist. But with the Internet you have other conspiracy theorists who share your failed ideas, kind of. You have 0.001 percent of all world engineers behind your failed ideas; and with the Internet that feels like a massive pile of ample support. Good for you

[Tony Szamboti]

I don't think that really matters. His calculations have been shown to be wrong (repeatedly) on some very basic principles, and his experience or lack thereof really don't add anything to this particular argument.

Anyone with a basic understanding of physics can see where his claim goes off the rails, and various people have provided that basic background for those who haven't studied this elsewhere.

Which calculations would they be Hokulele?

Legitimate people back up their claims with data. Are you legitimate or just a noisemaker hiding behind a psuedoname on the Internet?

[Newtons Bit]

How many buildings has Tony designed?

You're asking the wrong question. What you're doing is basically an appeal to authority. The question you should be asking is, "where is the calculations that show the collapse is impossible?"

[funk de fino]

Which calculations would they be Hokulele?

Legitimate people back up their claims with data. Are you legitimate or just a noisemaker hiding behind a psuedoname on the Internet?

You are owe all of us a video of Silverstein saying it was CD for safety purposes then

Get to it Tony

[Tony Szamboti]

You are owe all of us a video of Silverstein saying it was CD for safety purposes then

Get to it Tony

I did try to get a CD of that show from the History Channel and they told me that the History's Business shows are not available to the public.

[GlennB]

I did try to get a CD of that show from the History Channel and they told me that the History's Business shows are not available to the public.

And your explanation for why the WTC1 CD took several minutes to pull in the exterior columns is, similarly, unavailable to the public.

[Tony Szamboti]

And your explanation for why the WTC1 CD took several minutes to pull in the exterior columns is, similarly, unavailable to the public.

Not at all. I have said many times that I question the timeline given for the photos purportedly showing the south wall of WTC 1 bowing inwardly minutes before the collapse, since there is no video of this and it is known that the helicopters flying around the buildings all had video cameras onboard.

[Grizzly Bear]

But those bananna peel plumes with everything exploding up & outward is entirely genuine.... :rolleyes

[Tony Szamboti]

But those bananna peel plumes with everything exploding up & outward is entirely genuine.... :rolleyes

If you watch video of gravity driven collapse used in Verinage demolition you will not see the parabolic dust pluming we see in the video of the collapses of the towers.

[TruthersLie]

If you watch video of gravity driven collapse used in Verinage demolition you will not see the parabolic dust pluming we see in the video of the collapses of the towers.

You might just want to look up that word. I do no think it means what you think it means.

comparing apples to oranges AGAIN? really? A completely stripped building with NOTHING inside of it, vs intact buildings which are over 15x taller filled with drywall and office materials?

[Hokulele]

Which calculations would they be Hokulele?


In the original draft of the paper you submitted to JONES, you made a glaring error in that you calculated the average velocity and used that to claim there was no jolt, rather than calculate instantaneous changes in acceleration. This somehow made it through "peer review" (*snork*), and when this was pointed out by several people, rather than publish an acknowledgement or retract the paper, a substitution was made to the paper published in JONES.

It is discussed here (http://forums.randi.org/showthread.php?t=140639), and that thread contains a link to another forum where the errors were also discussed.

With those sort of shenanigans as an example of what you have done and what JONES will support in order to further their political agenda, it is no wonder that honest people realize that you and they have no credibility whatsoever.

Legitimate people back up their claims with data. Are you legitimate or just a noisemaker hiding behind a psuedoname on the Internet?


What would induce a tilt to the upper block after it had fallen several stories?

[R.Mackey]

Not at all. I have said many times that I question the timeline given for the photos purportedly showing the south wall of WTC 1 bowing inwardly minutes before the collapse, since there is no video of this and it is known that the helicopters flying around the buildings all had video cameras onboard.

For those of you just tuning in, the bolded section is a lie.

Even were this not the case, Tony is denying the timing of still photographs of the inward bowing effects -- seen and quantified on both Towers -- simply because it's inconvenient to his beliefs. He has no support for them not being bowed. There are numerous fallacies at work here, including Bare Assertion Fallacy, Destroying the Exception, Shifting Burden of Proof, and Call to Perfection.

Consider this carefully before deciding to try to reason with him.

[R.Mackey]

If you watch video of gravity driven collapse used in Verinage demolition you will not see the parabolic dust pluming we see in the video of the collapses of the towers.

If you have some evidence that the fluid flows seen are in any way unexpected -- you know, with "calculations," unless you're just a "noisemaker" -- then present them. But don't be surprised if I eat your lunch on this topic without cracking a sweat.

[Tony Szamboti]

In the original draft of the paper you submitted to JONES, you made a glaring error in that you calculated the average velocity and used that to claim there was no jolt, rather than calculate instantaneous changes in acceleration. This somehow made it through "peer review" (*snork*), and when this was pointed out by several people, rather than publish an acknowledgement or retract the paper, a substitution was made to the paper published in JONES.

It is discussed here (http://forums.randi.org/showthread.php?t=140639), and that thread contains a link to another forum where the errors were also discussed.

With those sort of shenanigans as an example of what you have done and what JONES will support in order to further their political agenda, it is no wonder that honest people realize that you and they have no credibility whatsoever.




What would induce a tilt to the upper block after it had fallen several stories?

Wow.

The way it is discerned that there was no jolt is that there was no velocity loss in the fall of the upper section of WTC 1.

The instantaneous acceleration vs. average acceleration issue was insignificant to the fact that there was no velocity loss. However, as it is a legitimate complaint that averaging should not be used it was corrected and a note made to the paper stating that it was revised for this reason.

A tilt can develop due to one side experiencing differential forces. Once something is in motion it doesn't take much. Try it with a model.

[GlennB]

..... This somehow made it through "peer review" (*snork*), and when this was pointed out by several people, .....

I'll have to start a new thread in 'forum community' over this *snorking* business.

[TruthersLie]

Wow.

The way it is discerned that there was no jolt is that there was no velocity loss in the fall of the upper section of WTC 1.

The instantaneous acceleration vs. average acceleration issue was insignificant to the fact that there was no velocity loss. However, as it is a legitimate complaint that averaging should not be used it was corrected and a note made to the paper stating that it was revised for this reason.

A tilt can develop due to one side experiencing differential forces. Once something is in motion it doesn't take much. Try it with a model.

There we go again...
thank you tony for showing your intellectual cowardice. You post, wait 30 minutes then come back in and edit your post to make it look like you have stated something else.

There you go people... intellecutal cowardice, ethcial lowlife, and moral hypocrite. Thank you very much TonyS.

[Tony Szamboti]

If you have some evidence that the fluid flows seen are in any way unexpected -- you know, with "calculations," unless you're just a "noisemaker" -- then present them. But don't be surprised if I eat your lunch on this topic without cracking a sweat.

I find the parabolic nature of the dust plumes to be a point of interest and if necessary will do the calculations.

Although you probably will never admit it, I haven't been wrong yet with any suspicions about these collapses. I told you a couple of years ago that I did not think there was a dynamic load and sure enough when we measured the drop of the upper section of WTC 1 there was no velocity loss. You had no choice but to admit to this lack of deceleration.

For those of you who refuse to believe that anything nefarious could have gone on the story then had to change to using the a tilt as a potential mechanism for obviating the need for an impulse. Sorry Ryan but there is only one reason for the lack of deceleration and you have to know it.

[Tony Szamboti]

There we go again...
thank you tony for showing your intellectual cowardice. You post, wait 30 minutes then come back in and edit your post to make it look like you have stated something else.

There you go people... intellecutal cowardice, ethcial lowlife, and moral hypocrite. Thank you very much TonyS.

You are quite a grouch there Mr. Truther.

I am not trying to do anything underhanded. If I edit a post the only purpose is to clarify things and since the discussion is ongoing there is always the chance for someone to bring up what is added. Your imputing that I am doing anything different is way over the top as well as the insults you seem to indulge yourself in for such inanity.

Get lost.

[TruthersLie]

You are quite a grouch there Mr. Truther.

I am not trying to do anything underhanded if I edit a post other than to clarify things. Your imputing that I am doing anything different is way over the top.

Oh poor tony.

Too bad we have SEEN YOU DO IT repeatedly. You will post some BS, and when people are replying to you, you change your post so that it makes them look bad.

I can count at least 4 instances where you have done it IN THIS THREAD.

Like I said, mental midget. Thank you for clearly demonstrating it. But I fully expect you to go in and change your reply that I am replying to right now.

[Tony Szamboti]

Oh poor tony.

Too bad we have SEEN YOU DO IT repeatedly. You will post some BS, and when people are replying to you, you change your post so that it makes them look bad.

I can count at least 4 instances where you have done it IN THIS THREAD.

Like I said, mental midget. Thank you for clearly demonstrating it. But I fully expect you to go in and change your reply that I am replying to right now.

There have been times when I was editing while people were responding simultaneously. In that case I have no idea they were responding. Of course you don't bring that possibility up. The entire issue is inane and I don't see how it affects an ongoing discussion.

You seem to be a crybaby and a rather nasty one at that. Can you add anything technical to the discussion or do we have to keep listening to you whine?

I really don't appreciate the insults and you have no basis for them. I would also say that making unwarranted insulting accusations is unethical to begin with, but even more so to do while using a psuedoname rather than your real name, like you do.

[R.Mackey]

I find the parabolic nature of the dust plumes to be a point of interest and if necessary will do the calculations.

You mean you haven't done the calculations? Then how do you know it's at all suspicious? Making stuff up again?

Although you probably will never admit it, I haven't been wrong yet with any suspicions about these collapses. I told you a couple of years ago that I did not think there was a dynamic load and sure enough when we measured the drop of the upper section of WTC 1 there was no velocity loss. You had no choice but to admit to this lack of deceleration.

You lie profusely about observed phenomena of the collapses, and you have for years -- your first denial of the tilt and the inward bowing dates back to 2007! Your "missing jolt" nonsense failed on inspection, the very first time I ever heard about it. This has been explained to you so many times it's not even funny.

Broken record, Tony.

[TruthersLie]

There have been times when I was editing while people were responding simultaneously. In that case I have no idea they were responding. Of course you don't bring that possibility up. The entire issue is inane and I don't see how it affects an ongoing discussion.

You seem to be a crybaby and a rather nasty one at that. Can you add anything technical to the discussion or do we have to keep listening to you whine?

I really don't appreciate the insults and you have no basis for them, especially considering the fact that you don't use your real name.

Thank you tony for EDITING YOUR POST AFTER I have posted... The defense rests your honor.

tsk tsk tsk.

I am still waiting to see how you can draw analogies between OKC, the other bombing and the WTC towers... you have brought them up as analogies and tried to pass it off... I'm still waiting to see if you understand how different designs and different construction methods will affect how a building reacts...

you keep using bad analogies.. so please flesh it out.

(again tony, in my research methods class you are currently earning a D-, you might want to pay more attention to research methods if you want to pass this class)

[Newtons Bit]

Although you probably will never admit it, I haven't been wrong yet with any suspicions about these collapses. I told you a couple of years ago that I did not think there was a dynamic load and sure enough when we measured the drop of the upper section of WTC 1 there was no velocity loss.

No, Tony. You're idealizing the collapse into a solid mass with a concentric impact on a spring. That's not reality. Both upper blocks tilted, thus there is no single uniform impact from the upper block to the lower block. Then it stands to that the dynamic effects are not individually measurable. Only the affect of the group can be measured. This effect is easily measured as the average acceleration of the upper block is less than gravity.

You're looking for one big-jolt in an environment that will never produce one. You need to look at how your assumptions are wrong and not assume (again incorrectly) that there's something magical or mystical about the collapse progression.

[TruthersLie]

There have been times when I was editing while people were responding simultaneously. In that case I have no idea they were responding. Of course you don't bring that possibility up. The entire issue is inane and I don't see how it affects an ongoing discussion.

You seem to be a crybaby and a rather nasty one at that. Can you add anything technical to the discussion or do we have to keep listening to you whine?

I really don't appreciate the insults and you have no basis for them. I would also say that making insulting accusations is especially unethical and cowardly (to use one of your favorite terms) to do while using a psuedoname rather than your real name, like you do.

You see tony, unlike you I don't edit my posts AFTER people have replied to them.

I had my name out there, and it was rather intersting that I had 5 or 6 twoofs emailing people where I live in Ras Al Khaimah (who I don't work for) to tell them I was saying I was a professor at their university. This is a small community, and as such it adversely affected my relationship here. So NO, I dont' go out of my way to tell folks my name. But if you look hard enough you can find me.

Ras Al Khaimah.
IT is a small place.

[Tony Szamboti]

No, Tony. You're idealizing the collapse into a solid mass with a concentric impact on a spring. That's not reality. Both upper blocks tilted, thus there is no single uniform impact from the upper block to the lower block. Then it stands to that the dynamic effects are not individually measurable. Only the affect of the group can be measured. This effect is easily measured as the average acceleration of the upper block is less than gravity.

You're looking for one big-jolt in an environment that will never produce one. You need to look at how your assumptions are wrong and not assume (again incorrectly) that there's something magical or mystical about the collapse progression.

The premise works the same for a series of smaller impacts. The energy dissipation is the same for the group whether it occurs all at once or with a series of smaller impacts. The result either way should be a velocity loss for the group, which is not observed.

The 0.3g resistance to the fall of the upper block is far less than the lower section of the building was capable of and is impossible short of impulsive loads which require deceleration and velocity loss, which are not observed. Something was removing the strength of the columns below.

[R.Mackey]

The 0.3g resistance to the fall of the upper block is far less than the lower section of the building was capable of

... assuming the mass fell squarely upon columns of an as-built structure, rather than hitting the floors, which of course most of it did ...

and is impossible short of impulsive loads which require deceleration and velocity loss, which are not observed. Something was removing the strength of the columns below.

And that something is impact damage and eccentric loading.

Put weight on an empty soda can. Measure how much force it can handle.

Now ding the side of the can and see how much it supports. Much less, huh?

If there is a single person on the entire JREF Forums other than Tony who doesn't understand what's going on here, please speak up.

[Newtons Bit]

The premise works the same for a series of smaller impacts. The energy dissipation is the same for the group whether it occurs all at once or with a series of smaller impacts.

No it doesn't. A number of small impacts over a period of time will not result in the same observable event as one large impact.

The result either way should be a velocity loss for the group, which is not observed.

There is an average ACCELERATION loss from a number of small impacts. It will appear as a continuous resistance. This is what was observed. There is nothing suspicious about it.

The 0.3g resistance to the fall of the upper block is far less than the lower section of the building was capable of and is impossible short of impulsive loads which require deceleration and velocity loss, which are not observed. Something was removing the strength of the columns below.

What?!?! How can you even possibly calculate that, much less state with any certainty that the observed resistance was not possible. You need to back up that claim or withdraw it.

[GlennB]

There is an average ACCELERATION loss from a number of small impacts. It will appear as a continuous resistance. This is what was observed. There is nothing suspicious about it.


Tony - why can't you understand that one simple point? Please explain.

[Tony Szamboti]

Tony - why can't you understand that one simple point? Please explain.

If you guys do some actual calculations showing how you can get to 0.3g average resistance and no need for any velocity loss at any point in the collapse, your case would have more plausibility. Up to now it has just been "the columns missed and impacted the floors", presuming columns at the beginning of the collapses severed completely and those lower down severed at their joints due to side loads etc.

Let's see some calculations for energy requirements vs. that available to back up these notions and claims.

[rwguinn]

No it doesn't. A number of small impacts over a period of time will not result in the same observable event as one large impact.



There is an average ACCELERATION loss from a number of small impacts. It will appear as a continuous resistance. This is what was observed. There is nothing suspicious about it.



What?!?! How can you even possibly calculate that, much less state with any certainty that the observed resistance was not possible. You need to back up that claim or withdraw it.
Anti-gravity, obviously. You see, .3g <1g, so the resis...
...well, ****, I don't have the foggiest notion how to get there from here...
We're back to "space Beams"...

[Newtons Bit]

If you guys do some actual calculations showing how you can get to 0.3g average resistance and no need for any velocity loss at any point in the collapse, your case would have more plausibility. Up to now it has just been "the columns missed and impacted the floors", presuming columns severed completely and those lower down buckled due to side loads etc.

Let's see some calculations to back up these notions and claims.

:confused::confused::confused::confused:

What you're asking for is impossible. What is possible, however, is to envelope the problem. On one end, we can assume that there is a minimum amount of resistance, call it zero. On the other side, we can assume that the columns all strike axially and there is a maximum amount of resistance. I've already done that calculation. (http://forums.randi.org/showthread.php?t=97584) It was an energy balance showing that even in the scenario that's most favorable to collapse prevention the collapse progresses easily. That's even assuming axial column strikes. About 50% of the energy is resisted.

What this means is that the 0.3g resistance you're looking for has been enveloped. It's done. It's over. I thought you already knew this stuff. Now stop trying to change the subject.

[Tony Szamboti]

:confused::confused::confused::confused:

What you're asking for is impossible. What is possible, however, is to envelope the problem. On one end, we can assume that there is a minimum amount of resistance, call it zero. On the other side, we can assume that the columns all strike axially and there is a maximum amount of resistance. I've already done that calculation. (http://forums.randi.org/showthread.php?t=97584) It was an energy balance showing that even in the scenario that's most favorable to collapse prevention the collapse progresses easily. That's even assuming axial column strikes. About 50% of the energy is resisted.

What this means is that the 0.3g resistance you're looking for has been enveloped. It's done. It's over. I thought you already knew this stuff. Now stop trying to change the subject.

Zero is not one of the bounds here. What I am asking for is a realistic estimate of the lower bound. I think it is possible to determine to a reasonable degree.

The problem with the 50% of the energy is resisted argument is that it only tells one side of the story, because that resistance is only about 10% of the strain energy of the columns below. What happened to the other 90%? Was it possible for 90% to get sidestepped? How much resistance do the floors provide? Can all of the columns miss each other all of the time? How much influence will friction have?

An estimate here, which could show that an average resistance of 0.3g and no velocity loss being necessary in a natural collapse were plausible would give some credibility to the argument of those who want to believe that nothing nefarious needed to have occurred.

[rwguinn]

:confused::confused::confused::confused:

What you're asking for is impossible. What is possible, however, is to envelope the problem. On one end, we can assume that there is a minimum amount of resistance, call it zero. On the other side, we can assume that the columns all strike axially and there is a maximum amount of resistance. I've already done that calculation. (http://forums.randi.org/showthread.php?t=97584) It was an energy balance showing that even in the scenario that's most favorable to collapse prevention the collapse progresses easily. That's even assuming axial column strikes. About 50% of the energy is resisted.

What this means is that the 0.3g resistance you're looking for has been enveloped. It's done. It's over. I thought you already knew this stuff. Now stop trying to change the subject.
No, his problem is worse than that.
It only resists at .3 g. His take on that is that the actual force it is counteracting is therefore only 30% of what it can normally hold up.
He fails to see that the .3g is the resistance to the dynamic load, and that that 30% 0f 1 g represents the actual ultimate load on the building.
for you non-technical types, in other words, if the building could hold up 30 million tons, the actual applied load is 100 million tons, and the building resists 30 million of that.
That is an over-simplification of where I think (That's an opinion, folks) he is headed here, but his arguments seem to lead that way.

ETA. The line of reasoning with the .3g resistance is so **********-up, that I am having trouble figuring out what he's doing. The above is a reasonable guess, based on what I have seen novice engineers do in the past (and I am likely guilty of that too. I learned, though)

[Newtons Bit]

Zero is not one of the bounds here. What I am asking for is a realistic estimate of the lower bound. I think it is possible to determine to a reasonable degree.

Then do it. You're the one who is making an extraordinary claim, thus the burden of proof is on you.

The problem with the 50% of the energy is resisted argument is that it only tells one side of the story, because that resistance is only about 10% of the strain energy of the columns below.

No. My calculation used 125% of the maximum strain energy of the columns (fixing for my angle error).

What happened to the other 90%? Was it possible for 90% to get sidestepped? How much resistance do the floors provide? Can all of the columns miss each other all of the time? How much influence will friction have?

You're delusional. I've already used 125% of the maximum strain energy assuming perfect concentric impacts.

An estimate here, which could show that an average resistance of 0.3g and no velocity loss being necessary in a natural collapse were plausible would give some credibility to the argument of those who want to believe that nothing nefarious needed to have occurred.

1. The velocity loss is the integral of the acceleration loss over the length of the building. It's not zero.

2. The estimate has already been done. Stop dodging.

[Tony Szamboti]

No, his problem is worse than that.
It only resists at .3 g. His take on that is that the actual force it is counteracting is therefore only 30% of what it can normally hold up.
He fails to see that the .3g is the resistance to the dynamic load, and that that 30% 0f 1 g represents the actual ultimate load on the building.
for you non-technical types, in other words, if the building could hold up 30 million tons, the actual applied load is 100 million tons, and the building resists 30 million of that.
That is an over-simplification of where I think (That's an opinion, folks) he is headed here, but his arguments seem to lead that way.

ETA. The line of reasoning with the .3g resistance is so **********-up, that I am having trouble figuring out what he's doing. The above is a reasonable guess, based on what I have seen novice engineers do in the past (and I am likely guilty of that too. I learned, though)

Dynamic loads require deceleration. There is none observed. The ultimate load would be several times the actual load. The 0.3g is 30% of actual load or about 10% of ultimate load.

You don't seem to have a good grip on this and I am surprised.

[Newtons Bit]

Dynamic loads require deceleration. There is none observed. The ultimate load would be several times the actual load. The 0.3g is 30% of actual load or about 10% of ultimate load.

This has already been explained to you. Stop treating the problem as if it is a single mass impacting a spring.

You don't seem to have a good grip on this and I am surprised.

True irony.

[rwguinn]

This has already been explained to you. Stop treating the problem as if it is a single mass impacting a spring.



True irony.
You seem to forget that there was Aluminum involved! Can't be TRUE irony...
:dl:

ETA, also: What does he think the .3g (.7 net on the "free fall" ) is?

[Newtons Bit]

You seem to forget that there was Aluminum involved! Can't be TRUE irony...
:dl:

I think a little piece of me just died :searghhhh:

ETA, also: What does he think the .3g (.7 net on the "free fall" ) is?

Voodoo? I don't know.

[rwguinn]

I think a little piece of me just died :searghhhh:

That's how the NWO kills you--a little piece at a time...


Voodoo? I don't know.

I'll buy that...

[9/11 Chewy Defense]

F= G, M, M2(squared) x Distance2(squared) divided by AR (air resistance). x SR (structural resistance)= No Free Fall Speed.

Truthers can't understand simple formulas.

[beachnut]

If you watch video of gravity driven collapse used in Verinage demolition you will not see the parabolic dust pluming we see in the video of the collapses of the towers.
E=mgh may not in your book of engineering. What engineering do you do?

Where is your Pulitzer Prize? Is it hiding with your calculations proving the towers can not fall due to gravity? 8 years and the best you can do is prove you can't apply engineering principles to your own delusions on the gravity collapse. ... a simple napkin calculation can show your ideas are junk. No wonder 99.99 percent of all engineers can see your conclusions are paranoid delusions.

Do you agree with Hoffman's thermite ceiling tiles delusion?

http://i286.photobucket.com/albums/ll116/tjkb/Sag1.jpg
Where is the real-cd-deal? No sounds of blasts, is this the thermite ceiling tiles?

http://i286.photobucket.com/albums/ll116/tjkb/Joneslie-1.jpg
At least you are with fellow liars like Jones who said this was due to thermite.
No wonder you have to lie about the bowing.
http://i286.photobucket.com/albums/ll116/tjkb/wtc1bowing.jpg
You have to quibble so you can spread paranoid conspiracy theories based on failed moronic delusions.
http://i286.photobucket.com/albums/ll116/tjkb/wtc2bowing.jpg
Source http://wtc.nist.gov/WTC_Conf_Sep13-15/session6/6McAllister.pdf
You can't do impossible calculations to support your delusion because of what reasons?

... Legitimate people back up their claims with data. Are you legitimate or just a noisemaker hiding behind a psuedoname on the Internet? Ironic you spew delusions about the WTC collapse and use your real name using the real name deal to bolster your delusional rant? You should have remained anonymous, be spared the embarrassment when you (if you) finally wake up from the ignorance you have on the gravity collapse of the WTC. Your data failed to back up your claim; does this mean you are not legitimate due to failed data?

[tsig]

A channel with equal length sides is nearly as strong against buckling as a box with those same side dimensions, in the direction of the two remaining perpendicular walls, since it is these perpendicular walls that generate over 95% of the moment of inertia in that direction whether it is a channel or box. I can show you the calculations for this if you don't understand.

.

You could explain what the moment of inertia has to do with buckling.

"Moment of inertia, also called mass moment of inertia or the angular mass, (SI units kg.m2) is a measure of an object's resistance to changes in its rotation rate."

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

[Tony Szamboti]

You could explain what the moment of inertia has to do with buckling.

"Moment of inertia, also called mass moment of inertia or the angular mass, (SI units kg.m2) is a measure of an object's resistance to changes in its rotation rate."

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

Moment of inertia is involved in the buckling equation. The greater the moment of inertia the greater the force a column can take without buckling. Buckling actually has something to do with rotation and is one reason why the buckle points are called plastic hinges.

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

[tsig]

Moment of inertia is involved in the buckling equation. The greater the moment of inertia the greater the force a column can take without buckling. Buckling actually has something to do with rotation and is one reason why the buckle points are called plastic hinges.

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

From the link:

"In engineering, buckling is a failure mode characterized by a sudden failure of a structural member subjected to high compressive stresses"

Is this what you meant:

"The second moment of area, also known as the area moment of inertia or second moment of inertia is a property of a shape that can be used to predict the resistance of beams to bending and deflection."

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

[TruthersLie]

If you guys do some actual calculations showing how you can get to 0.3g average resistance and no need for any velocity loss at any point in the collapse, your case would have more plausibility. Up to now it has just been "the columns missed and impacted the floors", presuming columns at the beginning of the collapses severed completely and those lower down severed at their joints due to side loads etc.

Let's see some calculations for energy requirements vs. that available to back up these notions and claims.

Again....
original post at 1245am (my time), 2 responses which tear it apart, and then edited at 115am (after those two posts). Go figure.

[Tony Szamboti]

From the link:

"In engineering, buckling is a failure mode characterized by a sudden failure of a structural member subjected to high compressive stresses"

Is this what you meant:

"The second moment of area, also known as the area moment of inertia or second moment of inertia is a property of a shape that can be used to predict the resistance of beams to bending and deflection."

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

Yes, it is the area moment of inertia (I) which is used.

[rwguinn]

Again....
original post at 1245am (my time), 2 responses which tear it apart, and then edited at 115am (after those two posts). Go figure.
Energy doesn't bend things. Force does.
Kinetic energy--once things start moving--is Force * distance. this is also the AVAILABLE potential energy before anything moves--m*g*h.
Distance is Velocity * time. Take the energy of the upper block. It is 88 stories up in the air. Multiply that distance times the weight of the upper block
Now, plug that in to the F=PE/d, and find out how much deflection of any component of the LOWER block will generate a FORCE in excess of its carrying capacity. Ain't gonna be much.

[Newtons Bit]

From the link:

"In engineering, buckling is a failure mode characterized by a sudden failure of a structural member subjected to high compressive stresses"

Is this what you meant:

"The second moment of area, also known as the area moment of inertia or second moment of inertia is a property of a shape that can be used to predict the resistance of beams to bending and deflection."

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

Buckling is a function of the slenderness ration. The slenderness ratio is equal to K*L/r. r is the radius of gyration. It is equal to (I/A)^0.5. I is the moment of inertia.

[R.Mackey]

I asked this question a little while ago:

If there is a single person on the entire JREF Forums other than Tony who doesn't understand what's going on here, please speak up.


... aaaand nobody responded.

So, Tony, you are alone.

You still believe things that are patently untrue, despite having it shown to you over and over and over again in glorious color motion photography, namely the rotation of the upper portion before vertical descent and collapse. Since you can't even get past this, and you're the only person having trouble here, this conversation is moot. We are not responsible for convincing you of what is real, and what is your imagination.

Ergo, re-read all the corrections given you already until you get it. There is nothing more anyone can be expected to do to help you.

[Tony Szamboti]

I asked this question a little while ago:




... aaaand nobody responded.

So, Tony, you are alone.

You still believe things that are patently untrue, despite having it shown to you over and over and over again in glorious color motion photography, namely the rotation of the upper portion before vertical descent and collapse. Since you can't even get past this, and you're the only person having trouble here, this conversation is moot. We are not responsible for convincing you of what is real, and what is your imagination.

Ergo, re-read all the corrections given you already until you get it. There is nothing more anyone can be expected to do to help you.

I think I do understand what is going on in this particular section of the JREF forums for the most part. It is called denial.

The answers I have seen on this forum, thus far, for how a natural collapse of the twin towers and WTC 7 could have occurred, in the manners observed, simply don't wash. It has not been shown how a 0.3g average resistance and no velocity loss could be a natural occurrence in the twin tower collapses. I also haven't seen a rational answer here for the 8 story 2.25 second freefall acceleration of WTC 7 being possible naturally either.

Just saying it doesn't make it true, although some here seem to think that is possible also. You guys have not made your case.

[Grizzly Bear]

Just keep telling yourself that...

[rwguinn]

If it was falling at .7 g acceleration instead of 1g acceleration, there is a velocity loss of 9.66 ft/sec2, or 2.94 m/sec2...

[Tony Szamboti]

If it was falling at .7 g acceleration instead of 1g acceleration, there is a velocity loss of 9.66 ft/sec2, or 2.94 m/sec2...

That is not a velocity loss. The collapses continually gained velocity at 0.7g and never decelerated. No deceleration means no amplified loads.

[BasqueArch]

I asked this question a little while ago:

Originally Posted by R.Mackey View Post
If there is a single person on the entire JREF Forums other than Tony who doesn't understand what's going on here, please speak up.


... aaaand nobody responded.

So, Tony, you are alone.

You still believe things that are patently untrue, despite having it shown to you over and over and over again in glorious color motion photography, namely the rotation of the upper portion before vertical descent and collapse. Since you can't even get past this, and you're the only person having trouble here, this conversation is moot. We are not responsible for convincing you of what is real, and what is your imagination.

Ergo, re-read all the corrections given you already until you get it. There is nothing more anyone can be expected to do to help you.


Yes Ryan, there are some things I don’t understand that perhaps you can explain:



I don’t understand why Tony repeatedly misrepresented NIST when he claimed “that the NIST calculated a 29 million lb. static load capacity for the floor system outside of the core on each story” , when what NIST said was “ … a total vertical load capacity for the connections on a typical floor of 29,000,000 lb ” and the static load capacity for the floor system was substantially less.

I don’t understand why Tony believes that the WTC1 top did not tilt before falling when the visual evidence proves the opposite and he ignores the indisputable WTC2 tilt.

I don’t understand why Tony believes “the complete central core itself was fully braced within itself” … “ It did not need lateral support from the floors and perimeter” when the original engineers designed core column bracing to the outside the core floor slabs and called it and detailed it so.

I don’t understand why Tony believes it is “magical” for the tilted upper block columns to have fallen onto the slab below and not onto the columns below, when the visual evidence shows the tilted upper block columns misaligned by many degrees and feet.

I don’t understand why Tony claims there should be a noticeable jolt when the enormous dynamic upper block columns load and columns footprint fell upon the damaged light floor slab below.

I don’t understand why Tony claims his own smooth, less than free fall speed velocity graphs prove CD and not a gravity-only collapse.

I don’t understand why Tony believes that the perimeter columns collapsed suddenly, when the visual evidence clearly shows the perimeter columns slowly buckling over a period of many minutes.

I don’t understand why Tony believes the core columns were CD’d every three stories , as the perimeter columns would have fallen inward toward the core and attached to floor joists, when the visual evidence proves the perimeter columns toppled outward, unattached to any floor joists.

I don’t understand why Tony believes the core columns were completely CD’d every three stories, when the visual evidence shows 40 and 60 stories “spires” of core columns upright after the floor slabs fell past the core columns.

I don’t understand why Tony believes with Chandler, that 4 ton perimeter columns were explosively propelled outward 600 feet, when the visual evidence proves the perimeter columns toppled over in unexploded continuous sheets, 600 feet (50 stories) away.

I don’t understand why Tony believes with Chandler, that 4 ton perimeter columns were explosively propelled outward 600 feet at 50 mph, when Chandler’s own numbers show the explosively propelled columns should have outdistanced the trailing dust clouds by a factor of at least 2, but did not. Dust clouds produced, no flying perimeter columns seen.

I don’t understand why Tony believes a “pyroclastic” dust cloud can only be created by explosives when the same clouds are produced by the verinage, nonexplosives demolition of buildings when falling concrete hits stationary concrete, CD or not CD, and where fire damaged naturally collapsing buildings also produce the same voluminous clouds.

I don’t understand why Tony believes that his fragmented numerical arguments can disprove the other overwhelming, established, integrated gravity-only visual facts to the contrary.


Perhaps what I don’t understand about Tony lies not in numbers and calculations, evidence and proof, but in other areas of science and the human mind.

Some people don’t recognize their face in the mirror.

================================================== =
You can't reason someone out of something they weren't reasoned into. -Swift

[Newtons Bit]

That is not a velocity loss. The collapses continually gained velocity at 0.7g and never decelerated. No deceleration means no amplified loads.

You're a broken record.

It was constantly at a 1g acceleration and the resistance (dynamic loading included) from the lower block resulted in hundred of tiny "jolts". These "jolts" were applied over a large (comparatively speaking) period of time. The average of those jolts over the collapse time period resulted in a 0.3g loss of acceleration.

[rwguinn]

You're a broken record.

It was constantly at a 1g acceleration and the resistance (dynamic loading included) from the lower block resulted in hundred of tiny "jolts". These "jolts" were applied over a large (comparatively speaking) period of time. The average of those jolts over the collapse time period resulted in a 0.3g loss of acceleration.
A "D-" in Dynamics is still not failing...

[tfk]

Tony,

I've got a question for ya.

What happens to your jolt if, before the upper block hits any particular floor, that floor is already 2/3rds destroyed? If 2/3rd of the floor, all the supports for that floor and all its contents have already failed and are falling. And the last 1/3rd is simply hanging on.

The effect of this means that the 2/3rds material that made up the floor will be vertically dispersed between the floor on which it rested and the floor below, when it is overtaken by the upper block.

Tom

[Tony Szamboti]

You're a broken record.

It was constantly at a 1g acceleration and the resistance (dynamic loading included) from the lower block resulted in hundred of tiny "jolts". These "jolts" were applied over a large (comparatively speaking) period of time. The average of those jolts over the collapse time period resulted in a 0.3g loss of acceleration.

0.3g loss is equivalent to about 10% of the strain energy of the columns below. What happened to the other 90%? Did it just fall out of the way?

With a continuous acceleration of 0.7g and just 0.3g resistance it can't be claimed that there was the dynamic load needed to cause an overload of the structure below, which was designed to handle several times the load above it.

The broken record is your insistence that a 0.3g contiuous resistance is somehow plausible in a natural collapse.

[Tony Szamboti]

Tony,

I've got a question for ya.

What happens to your jolt if, before the upper block hits any particular floor, that floor is already 2/3rds destroyed? If 2/3rd of the floor, all the supports for that floor and all its contents have already failed and are falling. And the last 1/3rd is simply hanging on.

The effect of this means that the 2/3rds material that made up the floor will be vertically dispersed between the floor on which it rested and the floor below, when it is overtaken by the upper block.

Tom

2/3rds of the 97th floor were not destroyed in the North Tower. Additionally, the 2/3rds value doesn't work as it does not account for the factor of safety. For what you are saying to be true 9/10ths would have to be destroyed with only 1/10th simply hanging on and a 0.3g resistance would be experienced. In reality, that is probably what happened but it can be shown that it could not have been the aircraft impacts or fire that caused the 90% reduction in strength.

[Furcifer]

0.3g loss is equivalent to about 10% of the strain energy of the columns below.

lol. You're just making stuff up. Mixing and mashing terms to suit your fantasy.

"g" factor rating. That's priceless. How did you come up with this again?

[rwguinn]

lol. You're just making stuff up. Mixing and mashing terms to suit your fantasy.

"g" factor rating. That's priceless. How did you come up with this again?
Once again, Tony is equating the acceleration reduction to the total load, and calling it "resistance".
His scenario has the falling portion of the building having less energy than the same mass at rest atop the other 88 floors.

[ElMondoHummus]

Yes Ryan, there are some things I don’t understand that perhaps you can explain:



I don’t understand why Tony repeatedly misrepresented NIST when he claimed “that the NIST calculated a 29 million lb. static load capacity for the floor system outside of the core on each story” , when what NIST said was “ … a total vertical load capacity for the connections on a typical floor of 29,000,000 lb ” and the static load capacity for the floor system was substantially less.

I don’t understand why Tony believes that the WTC1 top did not tilt before falling when the visual evidence proves the opposite and he ignores the indisputable WTC2 tilt.

I don’t understand why Tony believes... (snip)

I believe your sig pretty much explains all of the delusions proffered by your target:


You can't reason someone out of something they weren't reasoned into. -Swift

[Newtons Bit]

0.3g loss is equivalent to about 10% of the strain energy of the columns below. What happened to the other 90%? Did it just fall out of the way?

With a continuous acceleration of 0.7g and just 0.3g resistance it can't be claimed that there was the dynamic load needed to cause an overload of the structure below, which was designed to handle several times the load above it.

The broken record is your insistence that a 0.3g contiuous resistance is somehow plausible in a natural collapse.

Stop making :rule10 up. Using the Ross numbers, the total energy available is 2256MJ. I've calculated that the absolute maximum plastic strain energy of both the upper block and lower block amounts to 459M (20%). And in reality, less than a tenth of that would actually be used as most of the columns would fail at either their splices or their connections to the floor.

[tfk]

2/3rds of the 97th floor were not destroyed in the North Tower. Additionally, the 2/3rds value doesn't work as it does not account for the factor of safety. For what you are saying to be true 9/10ths would have to be destroyed with only 1/10th simply hanging on and a 0.3g resistance would be experienced. In reality, that is probably what happened but it can be shown that it could not have been the aircraft impacts or fire that caused the 90% reduction in strength.


You're not getting what I am saying...

None of this is related to factor of safety.

Let's assume that, for WTC1, the initial column failure happened at the 98th floor.

As you know, the columns were 3 column wide x 3 story tall assemblies, with adjacent assembly joints staggered by 1 story up & 1 story down. When they failed they failed as 3-story-high units.

This means that, when the 98th story columns pop, 1/3rd of the column assemblies pop for the 97th - 99th floor. 1/3rd of the columns pop for the 96th - 98th floors. And 1/3rd pop for the 98th - 100th floor.

Total it up, and as soon as the 98th floor pops, BEFORE the upper block drops 1 foot, all of the 98th floor supports are immediately gone, as well as 2/3rds of the 97th & 99th floors, and 1/3rd of the 96th & 100th floor.

The true situation is actually worse than this for the structural integrity of the remains of the 97th & 99th floor. You'd only have this (1/3rd supports remaining) situation if the core column joints and external column joints were indexed to each other. This is highly unlikely.

If adjacent core column are 1-story-staggers, then it's more like 1/9th of the columns are supported at both ends.

Get it...?

Tom

[Dave Rogers]

Both upper blocks tilted, thus there is no single uniform impact from the upper block to the lower block. Then it stands to that the dynamic effects are not individually measurable. Only the affect of the group can be measured. This effect is easily measured as the average acceleration of the upper block is less than gravity.

Since we've all lost count of the number of times anyone has tried and failed to explain this perfectly simple piece of elementary physics to Tony, is it about time somebody implemented a digital counter?

Dave

[Tony Szamboti]

Since we've all lost count of the number of times anyone has tried and failed to explain this perfectly simple piece of elementary physics to Tony, is it about time somebody implemented a digital counter?

Dave

Dave, are you going to count the post you made here in the last week where you stated that in WTC 1 the north wall would have been pushing upward when the south wall collapsed generating a torque that caused a rotation towards the south? It has since been explained to you that the north wall could not be pushing upward to generate a torque, and that the collapse of the south wall would have generated a moment towards the south causing the upper section to lessen it's load on the north wall, but that this moment would be resisted by the east and west walls.

You also erroneously thought that the south wall provided 25% of the building's resistance to overturn in that direction. It was then explained to you that in reality the east and west walls would have provided the vast majority or well over 95% of the resistance in that direction. Did you count this little piece of simply wrong elementary advice you tried to give me?

Given that you actually made these erroneous statements on this forum recently, and were publicly corrected, I am very surprised that you are actually indulging yourself in the use of ridicule, and especially when you provide no basis for it.

[Tony Szamboti]

You're not getting what I am saying...

None of this is related to factor of safety.

Let's assume that, for WTC1, the initial column failure happened at the 98th floor.

As you know, the columns were 3 column wide x 3 story tall assemblies, with adjacent assembly joints staggered by 1 story up & 1 story down. When they failed they failed as 3-story-high units.

This means that, when the 98th story columns pop, 1/3rd of the column assemblies pop for the 97th - 99th floor. 1/3rd of the columns pop for the 96th - 98th floors. And 1/3rd pop for the 98th - 100th floor.

Total it up, and as soon as the 98th floor pops, BEFORE the upper block drops 1 foot, all of the 98th floor supports are immediately gone, as well as 2/3rds of the 97th & 99th floors, and 1/3rd of the 96th & 100th floor.

The true situation is actually worse than this for the structural integrity of the remains of the 97th & 99th floor. You'd only have this (1/3rd supports remaining) situation if the core column joints and external column joints were indexed to each other. This is highly unlikely.

If adjacent core column are 1-story-staggers, then it's more like 1/9th of the columns are supported at both ends.

Get it...?

Tom

Tom, why don't you do some actual analysis here and see if you can get to a resistance of just 10% of the original strength of the columns or 0.3g?

[R.Mackey]

Tom, why don't you do some actual analysis here and see if you can get to an average resistance of just 10% of the original strength of the columns or 0.3g?

fixed that for you

[9/11 Chewy Defense]

The building (WTC1) twisted while it was collasping, it fell down due to structural damage (Plane & fires) & gravity.

End of story!

[Tony Szamboti]

fixed that for you

Thank you. I did mean to say average.

[Newtons Bit]

Tom, why don't you do some actual analysis here and see if you can get to a resistance of just 10% of the original strength of the columns or 0.3g?

Repeating a fact does not make it true. Argumentum ad Naseum is boring.

[Dave Rogers]

Given that you actually made these erroneous statements on this forum recently, and were publicly corrected, I am very surprised that you are actually indulging yourself in the use of ridicule, and especially when you provide no basis for it.

Having been corrected, and found myself capable of understanding the correction, I fail to see the problem here. I can see that the resistance to shear was provided principally by the moment frames formed by the east and west walls. Note, however, that it's the loss of support from the north wall that results in a moment being exerted upon this frame in the first place, and hence in the excess loads on the northern columns in both walls, and that this is the moment that results in the failure of those columns and the progressive failure of the remaining columns across these walls, as has been observed in videos posted in this thread. To suggest otherwise would be to suggest that the collapse of the north perimeter columns played no part in collapse initiation, which is absurd.

You see how that works? Somebody who knows something I don't, tells me about it. I pay attention to what they say, and revise my understanding accordingly. You should try it.

Dave

[Tony Szamboti]

Repeating a fact does not make it true. Argumentum ad Naseum is boring.

Hold your horses there Newton. Whether you like it or not the reality is that no actual analysis has been done to show why the average resistance was only 0.3g. There are also no steps to speak of in the velocity data.

Right now there is a massive hole in the NIST explanation as they can't use Bazant for collapse propagation since he requires an impulse, which is not observed.

You will have to pardon me if I don't accept simple comments in place of analysis.

[Tony Szamboti]

Having been corrected, and found myself capable of understanding the correction, I fail to see the problem here. I can see that the resistance to shear was provided principally by the moment frames formed by the east and west walls. Note, however, that it's the loss of support from the north wall that results in a moment being exerted upon this frame in the first place, and hence in the excess loads on the northern columns in both walls, and that this is the moment that results in the failure of those columns and the progressive failure of the remaining columns across these walls, as has been observed in videos posted in this thread. To suggest otherwise would be to suggest that the collapse of the north perimeter columns played no part in collapse initiation, which is absurd.

You see how that works? Somebody who knows something I don't, tells me about it. I pay attention to what they say, and revise my understanding accordingly. You should try it.

Dave

I was the first one to correct you and that was then reinforced by others.

What you also haven't done is reply to my earlier posts about why other structures that lost a full face did not experience rotation.

You have also not responded to the posts bringing up the fact that the NIST analysis does not show an overload for the east and west walls of WTC 1.

[Dave Rogers]

What you also haven't done is reply to my earlier posts about why other structures that lost a full face did not experience rotation.

Well, I did point out that they were radically different structures, and appeared to be constructed from radically different materials, so would be expected to behave differently. It may not be a reply you considered satisfactory, but it was a reply.

You have also not responded to the posts bringing up the fact that the NIST analysis does not show an overload for the east and west walls of WTC 1.

There doesn't need to be an overload for the entire wall. There only needs to be an overload for a single element or a small group of elements at one edge of the wall. When those elements then fail, the load paths are redistributed, and another element is overloaded, in a progressive failure. And so on. Again, this is fairly fundamental stuff.

Dave

[Tony Szamboti]

Well, I did point out that they were radically different structures, and appeared to be constructed from radically different materials, so would be expected to behave differently. It may not be a reply you considered satisfactory, but it was a reply.



There doesn't need to be an overload for the entire wall. There only needs to be an overload for a single element or a small group of elements at one edge of the wall. When those elements then fail, the load paths are redistributed, and another element is overloaded, in a progressive failure. And so on. Again, this is fairly fundamental stuff.

Dave

The NIST report does not provide any analysis that shows any elements or group of elements in either the east or west walls of WTC 1 were overloaded.

How have you determined that there was any overloaded elements in these walls?

[Dave Rogers]

How have you determined that there was any overloaded elements in these walls?

Where do you imagine I said I had?

Dave

[Grizzly Bear]

I'm sorry if this is a derail, but I have to ask this because the thing that seems to be on so many CT'ists minds is how Bazant's paper was intended to be an absolute model for the collapse of the towers.... I have a question... with all of the discussion about it, and as many times as it has been covered.... just how dense do people have to be to not be able to comprehend this:

We've had a lot of discussion on Dr. Bazant's paper. This discussion follows a familiar pattern.

First, bear in mind that he wrote several papers. The one that gets all of the attention is the 2001 paper with Dr. Yong Zhou, which only considers the progressive nature of collapse. It was written only two days after 9/11. So it has a lot of simplifications.

Those simplifications include an assumption that the initial failure would be a drop of a complete story, after the columns (all of them) on that floor were weakened to the point that they yielded under the load. It also includes a "worst case" assumption that the structure below this failing floor was completely intact, unweakened, and would catch the falling mass on the columns, rather than on the much weaker floors. The point of the paper is to show that, even under this extremely optimistic case, the Tower would still not be strong enough to resist the momentum of the falling weight, and would collapse.

So now it's been eight years, and various people have studied every single frame of every video a hundred times. We now know that the initial collapse was a rotation, dipping one edge about three floors before the last supports yielded, rather than a single floor suddenly yielding uniformly. Not a big surprise. We also know, as we did all along, that the falling mass did not land squarely on the columns below. So we don't expect Bazant & Zhou to be a very good model of what happened.

It was never intended to be one. It's a limiting case. It proves that, no matter what, the Towers were going to collapse. What actually happened looks rather different, but was even harder to withstand than the limiting case they proposed.

So, to the questions: You've proposed failures in 3-story lengths. There isn't much support for that early in the collapse. We believe that some core columns actually tore, although the perimeter, the bowing sections, did fail in lengths of three or even six stories when they buckled. But that doesn't matter.

Your opponent is complaining that Dr. Bazant doesn't treat the cause of initiation in much detail. Of course not! He had almost no information about the Towers. He assumed that a temperature of 800oC was one possible explanation, and that's all. We don't need his paper for this, we have NIST for this, and NIST demonstrates that a much, much lower temperature -- combined with impact damage, fireproofing damage, floor bowing, and creep -- is what started the collapse. Your opponent is complaining about something that isn't even important to the paper.

Dr. Bazant does not, as your opponent claims, assume the worst loading condition. If the lower columns are hit squarely and simultaneously, this allows them to generate the greatest impulse in response, and thus have the greatest chance of survival. What actually happened, however, is the impact was indeed "smeared." This is because of the tilting behavior. That tilt, unfortunately, put the weight not on the columns, but on the floors. Those floors were never designed to carry the upper portion. Even if they were fully intact, they could support at most about 40% of the weight that was gradually dumped on them, and they were heavily damaged besides.

As a result, there is no impulse loading needed. The upper mass settles on the floors, the floors fail, as the floors fail the perimeter columns are no longer stabilized and they break away through bolt failure instead of buckling. The core actually survives the collapse, punching its way through the descending mass, but it is unstable to begin with and being loaded strangely by the debris at the bottom, so it collapses too a few seconds later.


what part about a limiting case... do people not understand? How dense do people have to be to spend 8 years UNABLE TO UNDERSTAND WHAT A FREAKING LIMITING CASE IS..... after reading the SAME damn paper hundreds of times?

[Newtons Bit]

Hold your horses there Newton. Whether you like it or not the reality is that no actual analysis has been done to show why the average resistance was only 0.3g. There are also no steps to speak of in the velocity data.

Right now there is a massive hole in the NIST explanation as they can't use Bazant for collapse propagation since he requires an impulse, which is not observed.

You will have to pardon me if I don't accept simple comments in place of analysis.

I'm referring to your 10% of the strain energy claim which has already been shown to be false. Try reading.

[NutCracker]

what part about a limiting case... do people not understand? How dense do people have to be to spend 8 years UNABLE TO UNDERSTAND WHAT A FREAKING LIMITING CASE IS..... after reading the SAME damn paper hundreds of times?

You don't understand. Everything that opposes my views is wrong! It has to be wrong, because I can't afford to start to doubt. I can't start to doubt because then my views start to unravel. My views will start to callapse with the slightest touch of reason because my views hold together like a sheet cleaning paper that has been lying in the woods for years. So everything you throw at me is wrong, wrong, wrong. And I'll show you, you are wrong: if I object I prove you wrong!

--
Typical B. Truther

[tsig]

I'm sorry if this is a derail, but I have to ask this because the thing that seems to be on so many CT'ists minds is how Bazant's paper was intended to be an absolute model for the collapse of the towers.... I have a question... with all of the discussion about it, and as many times as it has been covered.... just how dense do people have to be to not be able to comprehend this:



what part about a limiting case... do people not understand? How dense do people have to be to spend 8 years UNABLE TO UNDERSTAND WHAT A FREAKING LIMITING CASE IS..... after reading the SAME damn paper hundreds of times?

I don't think they have even read it once. Understand it..never.

[R.Mackey]

I'm sorry if this is a derail, but I have to ask this because the thing that seems to be on so many CT'ists minds is how Bazant's paper was intended to be an absolute model for the collapse of the towers.... I have a question... with all of the discussion about it, and as many times as it has been covered.... just how dense do people have to be to not be able to comprehend this [...]

what part about a limiting case... do people not understand? How dense do people have to be to spend 8 years UNABLE TO UNDERSTAND WHAT A FREAKING LIMITING CASE IS..... after reading the SAME damn paper hundreds of times?

Pretty dense.

What's funnier is that even Tony's own calculations show that there would be a total collapse -- his optimistic numbers, assuming square impacts column-on-column, come up about 27% short of the energy absorption to needed to stop the collapse, for WTC 1. For WTC 2 the situation is much worse and I don't think he's even estimated it.

Now, Tony will next wave his hands and say that "vibration and sound" and so on will handily make up for the 27%, which is complete malarkey and he hasn't even tried to quantify it...

His other line of retreat is to again insist "there's no jolt." And, as before, had there been a square column-on-column impact after a clean fall, there likely would be a discernible jolt, but that didn't happen. However, since even his own calculation leads to a collapse, one must rationally conclude that if there were any explosives, they weren't there to cause a collapse, but instead only to make the collapse faster. Why it needed to be faster is still an unexplored problem.

[tfk]

Tom, why don't you do some actual analysis here and see if you can get to a resistance of just 10% of the original strength of the columns or 0.3g?
Tony,

Why don't you answer my question?

1. If 60% - 90% of all the supports for the floors on BOTH the 87th & 89th floors have already been destroyed PRIOR to the mutual impact of those floors, what does that do you your "jolt".

You've done the "jolt" analysis. You know (I presume...) the assumptions that are built into the analysis.

2. The limitation on the force that can be applied by the bottom portion of the towers onto the upper portion of the towers is the (tiny) fraction of the load that the massively damaged 99th floor structures can withstand without failing completely. Floor structures that retain only 10 - 30% of their supports.

3. But here's a second problem: What on earth would make you think that a floor structure could withstand as much load in an UPWARD direction as it can withstand in a DOWNWARD direction? These were floor trusses whose ends SAT ON TOP OF angle iron, and were BOLTED in place. Do you really think that these assemblies could withstand equal upward & downwards loads?

4. If the lower floors fracture & fail (due to snapping of 2/3rds or more of their supports and the consequent gravity collapse of most of that floor) PRIOR to the upper block arriving at that particular floor, then how much of the upper block's momentum is lost in causing THAT PARTICULAR damage?

Tony, these are not hard questions.
___

Tony, you've been provided with several reasons that your jolt may be missing or simply undetected by your analysis methods.

If the collisions do not happen on a bunch of evenly separated, discrete planes located at each floor, due to any one of a dozen reasons, then your discrete jolts disappear.

If the collision impulse applied to the FRAME STRUCTURE of the upper block is small compared to the momentum of the upper block, then your discrete jolts disappear.

If your video images & analysis are inadequate to accurately measure the instantaneous accelerations of the upper block, then your jolts disappear.
___

You ask why I don't do an analysis?

The succinct answer is: "I don't have to, Tony."

I am not the one grasping at straws. There is a overwhelmingly convincing analysis, done by real experts, that answers the question.

There is a bunch of foolishness, produced by a tiny group of incompetent amateurs, that attempts to find some discrepancies by playing juvenile semantic games. After 8 years of this foolishness, NOT ONE of the alleged "gotcha's" withstand 5 minutes of knowledgeable scrutiny.

Not one, Tony.

Including your "missing jolt".

There is a mountain of evidence - hard, irrefutable evidence - that your fundamental conclusion is simply, ludicrously wrong. If you're inclined to take on the task of undermining that particular mountain, then it is up to YOU to start out by providing a competent analysis.

You have not done this. By a long shot.
___

There are three MechE's that have published on your side, Tony. Judy Wood, Gordon Ross & you.

I'll let you review (in your own mind) Wood's claim that a proper "conservation of momentum analysis" required the upper block to come to a dead stop at each floor & then resume falling... [I am slightly embarrassed that she spent some time at Cornell U, where I got my degree. But, then again, I DID attend some of the dorm parties they had there in the early 70s, and there was a certain amount of amateur pharmacology going on back then ...]

Gordon Ross offers one absolutely solid piece of advice at the beginning of each lecture of his that I've seen. He says, "Don't believe what I tell you." Superb advice. Of course, he thinks that he is being "open & modest" by telling his audience, "go check it out for yourself on the internet". In other words, "I'm not going to stand behind what I say here. I'll leave the conclusions up to you."

People sucking up to amateurs say, "I'll leave the conclusions up to you..."
People trafficking in innuendo & mud-slinging say, "I'll leave the conclusions up to you ..."
Scumball lawyers & political assassins say, "I'll leave the conclusions up to you ..."

Not one single competent engineer in the history of engineering has ever uttered anything like "I'll leave engineering analysis & conclusions up to you bunch of amateurs, based on evidence provided by a bunch of biased, politically motivated amateurs."

A competent engineer says one of two things: 1) NOTHING (which is equivalent to "I don't know") or 2) "The answer IS ..."

Why don't you look around, Tony. Why don't you ask those other 90 Mech Engr's at ae911t what they have contributed to competent analyses on the subject.

You've walked out on a limb, Tony. Or, more precisely, a scaffold. You, and Ross & Wood have put "professional nooses" around your own necks.

Now, you & Ross will probably survive this exercise. But, amongst competent engineers, ONLY by not saying a word about this foolishness. And hoping that no one in the crowd recognizes your name.

I admire your courage of your (misplaced) convictions.
I don't admire courage combined with incompetence.

It gives the rest of us a bad image.


Tom

[tfk]

Tom, why don't you do some actual analysis here and see if you can get to a resistance of just 10% of the original strength of the columns or 0.3g?

Just so that you don't think that I avoided your question...

What the hell does "the original strength (aka "the cumulative, axial load carrying capablility") of the columns" of an intact, undamaged, pristine, cross-braced, statically loaded, evenly stressed, symmetrically loaded, axially loaded, and properly assembled structure ...

have to do with ...

the cumulative load carrying capability of a bunch of bent, fractured, buckled, deformed, unbraced, asymmetrically loaded, failed, ripped apart, smashed with thousands of tons of LATERAL, DYNAMIC force, stub ends of columns?

I'm just curious...

Tom

[Tony Szamboti]

Just so that you don't think that I avoided your question...

What the hell does "the original strength (aka "the cumulative, axial load carrying capablility") of the columns" of an intact, undamaged, pristine, cross-braced, statically loaded, evenly stressed, symmetrically loaded, axially loaded, and properly assembled structure ...

have to do with ...

the cumulative load carrying capability of a bunch of bent, fractured, buckled, deformed, unbraced, asymmetrically loaded, failed, ripped apart, smashed with thousands of tons of LATERAL, DYNAMIC force, stub ends of columns?

I'm just curious...

Tom

If one looks at the Verinage technique demolitions in slow motion by dragging the slider on the video they will see that the upper block moves laterally on it's way down so there isn't a square column on column hit. But guess what, there is a jolt and deceleration every time the upper block contacts the lower block which is not being removed artificially.

It seems that you won't try to calculate the resistance of the lower block in WTC 1 because you know it would be much greater than 0.3g if nothing artificial was removing the strength of it's columns.

Your attempts to spin away from this are not going to change the reality that there was far less resistance than there should have been, and the fact that no jolt occurred shows the upper block was not doing the work to collapse the lower structure.

[Newtons Bit]

It seems that you won't try to calculate the resistance of the lower block in WTC 1 because you know it would be much greater than 0.3g if nothing artificial was removing the strength of it's columns.

Are you brain damaged? The analysis has already been run. LONG AGO. This is the second time that I've reminded you of this.

[Tony Szamboti]

Are you brain damaged? The analysis has already been run. LONG AGO. This is the second time that I've reminded you of this.

Are you saying you or anyone else did an analysis which shows why the resistance was only 0.3g and how no impulse would be required to cause collapse propagation? I don't recall such an analysis.

However, if you have it let's see it.

[BasqueArch]

If one looks at the Verinage technique demolitions in slow motion by dragging the slider on the video they will see that the upper block moves laterally on it's way down so there isn't a square column on column hit. But guess what, there is a jolt and deceleration every time the upper block contacts the lower block which is not being removed artificially.

It seems that you won't try to calculate the resistance of the lower block in WTC 1 because you know it would be much greater than 0.3g if nothing artificial was removing the strength of it's columns.

Your attempts to spin away from this are not going to change the reality that there was far less resistance than there should have been, and the fact that no jolt occurred shows the upper block was not doing the work to collapse the lower structure.

This is evidence of how little you know about how buildings are built.
At a glance any architect or structural engineer can see those are precast concrete slab buildings. The upper block falls onto thick stable undisturbed concrete floor slabs spanning a small distance atop structurally sound thick undisturbed concrete load bearing walls, not columns, therefore jolt. At WTC1,2 the top block columns, 238 enormous point loads fall upon 2.5"-4" floor slabs, not columns below therefore no jolt. But you can't tell the difference because you don’t know no better.

* click *


This is evidence of how little you know about how buildings are built.
At a glance any architect or structural engineer can see those are precast concrete slab buildings. The upper block falls onto thick stable undisturbed concrete floor slabs spanning a small distance atop structurally sound thick undisturbed concrete load bearing walls, not columns, therefore jolt. At WTC1,2 the top block columns, 238 enormous point loads fall upon 2.5"-4" floor slabs, not columns below therefore no jolt. But you can't tell the difference because you don’t know no better.

* click *


This is evidence of how little you know about how buildings are built.
At a glance any architect or structural engineer can see those are precast concrete slab buildings. The upper block falls onto thick stable undisturbed concrete floor slabs spanning a small distance atop structurally sound thick undisturbed concrete load bearing walls, not columns, therefore jolt. At WTC1,2 the top block columns, 238 enormous point loads fall upon 2.5"-4" floor slabs, not columns below therefore no jolt. But you can't tell the difference because you don’t know no better.

* click * < bump >

[Newtons Bit]

Are you saying you or anyone else did an analysis which shows why the resistance was only 0.3g and how no impulse would be required to cause collapse propagation? I don't recall such an analysis.

However, if you have it let's see it.

No Tony. You stated,

It seems that you won't try to calculate the resistance of the lower block in WTC 1 because you know it would be much greater than 0.3g if nothing artificial was removing the strength of it's columns.

Tom, why don't you do some actual analysis here and see if you can get to a resistance of just 10% of the original strength of the columns or 0.3g?

0.3g loss is equivalent to about 10% of the strain energy of the columns below. What happened to the other 90%? Did it just fall out of the way?

I've shown that the maximum strain of the columns is only 20% of the energy of the collapse. This does not account for where the columns actually failed: the splices. TFK has also explained why only 1/3rd of the columns could be resisting the collapse at any given point.

How hard can this really be to understand? It's plain as day.

[Mr.D]

Tony,

What is your estimate of the upper bound on the magnitude of the "missing" jolt?

Or to put it another way, what's your estimate of the largest "jolt" that could have happened that could not have been measured using your methods?

Just curious.

[Tony Szamboti]

No Tony. You stated,







I've shown that the maximum strain of the columns is only 20% of the energy of the collapse. This does not account for where the columns actually failed: the splices. TFK has also explained why only 1/3rd of the columns could be resisting the collapse at any given point.

How hard can this really be to understand? It's plain as day.

So you don't have an analysis showing how the average resistance could be just 0.3g and that no jolt was necessary.

I can't say I am surprised by that and your stonewalling answer.

[Tony Szamboti]

Tony,

What is your estimate of the upper bound on the magnitude of the "missing" jolt?

Or to put it another way, what's your estimate of the largest "jolt" that could have happened that could not have been measured using your methods?

Just curious.

The collapse of WTC 1's upper section continually accelerated at about 70% of the rate of gravity with no velocity loss at any point in the 114 feet the fall of the upper section could be measured.

We measured every 167 milliseconds and found no reduction in velocity at any time, so the largest jolt would have to be able to recover to pre-impact velocity and more in that 167 milliseconds.

I will have to calculate it and get back to you but a quick estimate would be around 1g which isn't really a jolt but the static load.

[beachnut]

So you don't have an analysis showing how the average resistance could be just 0.3g and that no jolt was necessary.

I can't say I am not surprised by that and your stonewalling answer.
When will you publish your findings in a real journal? When will you earn a Pulitzer Prize for breaking the biggest conspiracy in history? When will you learn to understand the gravity collapse?

never?

Funny you agree the video study you made can't show the jolt you are looking for. It clearly showed the reduced velocity as the WTC did not fall close to free fall. Why are your delusional ideas falling faster than free fall into the pit of ignorance known as Scholars for 9/11 Truth & Justice. Why did you pick the insane Jones group instead of the insane Fetzer group? Do you guys get the Bigfoot group discount at fantasy-land? Does anyone at your work place take you seriously? After 8 years what keeps you posting nut case delusions of controlled demolition? How does Hoffman's work about thermite ceiling tiles, Jones approved, fit into your overall fantasy? Do you guys at Scholars for 9/11 Truth & Justice have a single integrated scenario, or are you all open-loop crazy posting whatever crazy delusion you can promote to help sell your ideas of paranoid conspiracy theories? The sad part of Scholars for 9/11 Truth & Justice is your lack of evidence after 8 years after claiming you have ample evidence.

You have no work worthy of publication to support your wild speculation based on your own fantasy world of events you can't define or support with real world evidence.
Scholars for 9/11 Truth & Justice; endeavoring to address the unanswered questions of the September 11, 2001 attack through scientific research and public education. What a big lie. The truth; Scholars for 9/11 Truth & Justice spread lies about September 11, 2001 by making up the dumbest ideas they can and finding gullible people in the public too lazy to see your fraud.

Why not publish your great work in a real journal and come back to rub our posts in it? You have no real work based on reality; that is why you will no be published in a real journal.

What did Leslie Robertson say about your junk ideas?

Oh, yes he said, "nonsense". Good for you.

[Tony Szamboti]

When will you publish your findings in a real journal? When will you earn a Pulitzer Prize for breaking the biggest conspiracy in history? When will you learn to understand the gravity collapse?

never?

Funny you agree the video study you made can't show the jolt you are looking for. It clearly showed the reduced velocity as the WTC did not fall close to free fall. Why are your delusional ideas falling faster than free fall into the pit of ignorance known as Scholars for 9/11 Truth & Justice. Why did you pick the insane Jones group instead of the insane Fetzer group? Do you guys get the Bigfoot group discount at fantasy-land? Does anyone at your work place take you seriously? After 8 years what keeps you posting nut case delusions of controlled demolition? How does Hoffman's work about thermite ceiling tiles, Jones approved, fit into your overall fantasy? Do you guys at Scholars for 9/11 Truth & Justice have a single integrated scenario, or are you all open-loop crazy posting whatever crazy delusion you can promote to help sell your ideas of paranoid conspiracy theories? The sad part of Scholars for 9/11 Truth & Justice is your lack of evidence after 8 years after claiming you have ample evidence.

You have no work worthy of publication to support your wild speculation based on your own fantasy world of events you can't define or support with real world evidence.
What a big lie. The truth; Scholars for 9/11 Truth & Justice spread lies about September 11, 2001 by making up the dumbest ideas they can and finding gullible people in the public too lazy to see your fraud.

Why not publish your great work in a real journal and come back to rub our posts in it? You have no real work based on reality; that is why you will no be published in a real journal.

What did Leslie Robertson say about your junk ideas?

Oh, yes he said, "nonsense". Good for you.

When will you sit and think for a moment before you write something? You wouldn't be the type to jump to conclusions though would you? No, you wouldn't be the type to say the plane impacts were the equivalent of 1,300 tons of TNT so that is what had to be the cause for the tower collapses?

What is your excuse for WTC 7? That the fires were the equivalent of 1,000 tons of TNT so that had to be the cause?

[Grizzly Bear]

What is your excuse for WTC 7?
Well based on my reading I know already you have a problem with the relationship between temperature and the strength of structural steel (Or should I say, your "misreading" of the NIST report)... and your illiteracy with failure modes, and your illiteracy with fire behavior.... case studies (http://forums.randi.org/showpost.php?p=5202939&postcount=288), fluid dynamics (http://forums.randi.org/showpost.php?p=5214550&postcount=340), limiting cases in models (http://forums.randi.org/showpost.php?p=5223622&postcount=404)... I suggest you once again find a new hobby with that... :rolleyes...

What should I surmise from all of those?

[Tony Szamboti]

Well based on my reading I know already you have a problem with the relationship between temperature and the strength of structural steel... and your illiteracy with failure modes, and your illiteracy with fire behavior.... case studies (http://forums.randi.org/showpost.php?p=5202939&postcount=288), fluid dynamics (http://forums.randi.org/showpost.php?p=5214550&postcount=340), limiting cases in models (http://forums.randi.org/showpost.php?p=5223622&postcount=404)... I suggest you once again find a new hobby with that... :rolleyes...

First the NIST doesn't say WTC 7 came down due to a loss of strength in the steel from high temperatures. They say it was due to thermal expansion at temperatures where steel hasn't lost much strength at all. You apparently don't know or you wouldn't be so willing to call me illiterate with fire behavior.

I wonder if you actually even know that the NIST model only heats the steel and not the concrete. I wonder if you actually know that steel and concrete have the same Coefficient of thermal expansion. If you do know then tell me how the shear studs could have broken and allowed the steel beams to expand with no restraint from the concrete.

[TruthersLie]

When will you sit and think for a moment before you write something? You wouldn't be the type to jump to conclusions though would you? No, you wouldn't be the type to say the plane impacts were the equivalent of 1,300 tons of TNT so that is what had to be the cause for the tower collapses?

What is your excuse for WTC 7? That the fires were the equivalent of 1,000 tons of TNT so that had to be the cause?

Dodge noted.

Back to the original question

When will you actually publish ANYTHING in a REAL peer reviewed journal to support your nutty ideas?

(don't even bother to mention JONES... we all know the level of peer review there... come on tony man up. REAL peer review. Why can't ANY of you twoofs EVER do that? I have 3 peer reviewed journal articles on my CV... 3 more than da twoof... absolutely amazing and I didn't have to pay for a single one)

[cmcaulif]

So you don't have an analysis showing how the average resistance could be just 0.3g and that no jolt was necessary.

I can't say I am surprised by that and your stonewalling answer.

The analysis you are talking about is a consequence of what NB has said.

All you need to do is average the total strain energy over the height of one story.

Divide this term by mass and you get an acceleration, which you can subtract from g to find the average acceleration of the collapse.

[R.Mackey]

Once again, I remark that only Tony has a problem understanding his mistake. Since he is unwilling to be convinced, no progress is expected -- ever. Further responses are also unnecessary.

[GlennB]

The actual jolt would not be visible, since it occurs over a very short time frame.



We measured every 167 milliseconds and found no reduction in velocity at any time, so the largest jolt would have to be able to recover to pre-impact velocity and more in that 167 milliseconds.



ooops

[Dave Rogers]

I will have to calculate it and get back to you but a quick estimate would be around 1g which isn't really a jolt but the static load.

OK, so I've made a few changes to my jolt calculation. I've assumed linear increase in column force up to the ultimate strength at 0.2% compression, then constant strength from there to 20% compression, which (I think) grossly overestimates the resistance of the columns. I've set the ultimate strength at three times the static loading. I've assumed that every column in the upper block makes a perfect impact on the corresponding column in the lower block, thus grossly overestimating the ability of the structure to resist collapse. And finally, I've assumed the upper block is inclined at an angle of 4º about an axis parallel to the long side of the core, which is significantly less than the actual fall angle; making the angle parallel to a side also increases the jolt from the core-on-core impact. In short, I've made every possible effort to exaggerate the jolt from impact, other than assuming the upper block is level (because, of course, we know it wasn't, even at the first impact.

http://forums.randi.org/imagehosting/147644aded82a9b630.bmp (http://forums.randi.org/vbimghost.php?do=displayimg&imgid=17959)

Here's the result of acceleration against drop for the collapse of a single storey of supports. I see a maximum jolt of less than 0.7G, which indicates that the jolt would not be observable by the technique used.

If effects such as column-on-floor impacts, eccentric loading and (most importantly) failure at connections rather than mid-column, I would expect the resistance to be many times lower. Even so, it's perfectly clear to me that an angle of 4º is enough to reduce the intensity of any jolt below the measurement threshold.

Dave

ETA: Minor correction, I used 15% maximum compression, assuming a 4m storey height.

[Tony Szamboti]

ooops

You apparently do not understand that it is the velocity loss effects of the jolt which allow a determination of whether or not it occurred. There is a window much larger than 167 milliseconds for the velocity to recover to what it was pre-impact.

If you had read the paper you would have seen where we show that a 6g jolt would have required 800 milliseconds to recover to pre-impact velocity, and in that time we had four data points which show not only that there was no loss but that the velocity continued to increase.

[Dave Rogers]

If you had read the paper you would have seen where we show that a 6g jolt would have required 800 milliseconds to recover to pre-impact velocity, and in that time we had four data points which show not only that there was no loss but that the velocity continued to increase.

A jolt less than 1g doesn't result in any velocity loss, as the acceleration never falls below zero. The discretisation error alone on your data points prevents you from seeing any jolt that doesn't produce negative acceleration, as I think you estimated a few posts ago.

Dave

[Newtons Bit]

So you don't have an analysis showing how the average resistance could be just 0.3g and that no jolt was necessary.

I can't say I am surprised by that and your stonewalling answer.

Non-sequitur: my post was about your claim regarding the strain energy of the columns. Not about the jolts. Are you ever going to address challenges to your ridiculous claim:

0.3g loss is equivalent to about 10% of the strain energy of the columns below. What happened to the other 90%?

[Furcifer]

snip: in that time we had four data points which show not only that there was no loss but that the velocity continued to increase.

Because why? ;)

[Newtons Bit]

Once again, I remark that only Tony has a problem understanding his mistake. Since he is unwilling to be convinced, no progress is expected -- ever. Further responses are also unnecessary.

I'm feeling that way as well. He ignores every post which shows the concept of why no jolt was to be expected, and then responds to every other post (which isn't about the jolt) demanding an analysis on the jolt.

He's becoming Heiwa-esque.

[rwguinn]

I'm feeling that way as well. He ignores every post which shows the concept of why no jolt was to be expected, and then responds to every other post (which isn't about the jolt) demanding an analysis on the jolt.

He's becoming Heiwa-esque.Becoming?
Mackey is correct. The Initial Rotation of the upper block is Tony's irreducible assumption. He can't see it, because it negates everything else he's done.
And when it's pointed out, he, like the stage magician, tries to misdirect everyone by pointing to WTC 7...

[tfk]

OK, Tony,

If you won't answer these simple questions, I will.


Why don't you answer my question?


Because you know the inevitable implication of the answers is that your "missing jolt" simply evaporates.


1. If 60% - 90% of all the supports for the floors on BOTH the 87th & 89th floors have already been destroyed PRIOR to the mutual impact of those floors, what does that do you your "jolt".


A first order estimate: it reduces the jolt to 10% - 40% of what it would have been otherwise.


2. The limitation on the force that can be applied by the bottom portion of the towers onto the upper portion of the towers is the (tiny) fraction of the load that the massively damaged 99th floor structures can withstand without failing completely. Floor structures that retain only 10 - 30% of their supports.


Since the columns do not impact other columns, then the jolt is limited by the amount of energy it takes to fracture what is left of the massively damaged floors. Considering all the pre-existing damage, 5 - 15%


3. But here's a second problem: What on earth would make you think that a floor structure could withstand as much load in an UPWARD direction as it can withstand in a DOWNWARD direction? These were floor trusses whose ends SAT ON TOP OF angle iron, and were BOLTED in place. Do you really think that these assemblies could withstand equal upward & downwards loads?


A reasonable estimate of the upward load that the cross trusses can impress on the upper columns when loaded from below is an order of magnitude less than the trusses can impress on the lower columns when they are loaded from above.


4. If the lower floors fracture & fail (due to snapping of 2/3rds or more of their supports and the consequent gravity collapse of most of that floor) PRIOR to the upper block arriving at that particular floor, then how much of the upper block's momentum is lost in causing THAT PARTICULAR damage?


In this case, gravity fractures those floors, and their fracture takes no energy away from the descending upper block, except for the energy required to fracture some bolts & welds. But the impact is spread over 3 stories of fall, so the jolt disappears.


Tony, you've been provided with several reasons that your jolt may be missing or simply undetected by your analysis methods.

If the collisions do not happen on a bunch of evenly separated, discrete planes located at each floor, due to any one of a dozen reasons, then your discrete jolts disappear.

If the collision impulse applied to the FRAME STRUCTURE of the upper block is small compared to the momentum of the upper block, then your discrete jolts disappear.

If your video images & analysis are inadequate to accurately measure the instantaneous accelerations of the upper block, then your jolts disappear.


Everything that smears the impacts out, rather than making them discrete, instantaneous floor by floor events, serves to reduce or eliminate your jolt.

Everything that reduces the amount of force that the upper block floors can deliver to the upper block structural lattice reduces your jolt, too.


Why don't you ask those other 90 Mech Engr's at ae911t what they have contributed to competent analyses on the subject.


Because you know the answers. They've got nothing much to offer.


Tom

[tfk]

...You apparently don't know or you wouldn't be so willing to call me illiterate with fire behavior.

I wonder if you actually even know that the NIST model only heats the steel and not the concrete. I wonder if you actually know that steel and concrete have the same Coefficient of thermal expansion. If you do know then tell me how the shear studs could have broken and allowed the steel beams to expand with no restraint from the concrete.


Tony,

What would someone literate in thermoDYNAMICS say about the effect of the difference in thermal conductivity of steel & concrete on the TRANSIENT thermal expansion of the two during the heating phase?

How about the difference in heat capacity & mass of the two?

Gee, Tony. Do you think that perhaps there might have been a couple of competent thermodynamicists who analyzed this correctly? And found out that, in the relatively short period of time during which these assemblies were heated by fire (in any given location) that, FOR THE TRANSIENT RESPONSE during heating, there was inconsequential difference between an analysis that included both steel & concrete thermal expansion and one that ignored the expansion of the concrete.

What do you think?

Tom

[Mangoose]

IIRC Tony's measurements in his jolt paper took the white structure at the northwest corner of the roof as its main point of reference (particularly of the start of the descent), measuring the distance in pixels of the top of this structure and the upper border of the image. The collapse however was already in progress prior to any movement of this structure:

http://img65.imageshack.us/img65/9404/output2.gif

So Tony's measurements begin sometime after the initiation of the collapse on the South Face.

Also because of the tipping of the upper block, the white structure moved in three dimensions -- not simply down but also southward:

http://img405.imageshack.us/img405/2857/aniv.gif

The Sauret footage from the north obscures such movement to the south. Tony's measurements thus do not capture the full three-dimensional movement of the white structure on the roof.

[beachnut]

When will you sit and think for a moment before you write something? You wouldn't be the type to jump to conclusions though would you? No, you wouldn't be the type to say the plane impacts were the equivalent of 1,300 tons of TNT so that is what had to be the cause for the tower collapses?

What is your excuse for WTC 7? That the fires were the equivalent of 1,000 tons of TNT so that had to be the cause?
Tony, you need to be more precise and do the work first before spewing your own delusional speculation. The impact of flight 11 was 1357 pounds of TNT, not tons. The collapse released 130 TONS of TNT kinetic energy. The impact of Flight 175 was 2093 pounds of TNT kinetic energy impact. Do you want it in joules? 4,380,000,000 joules in the kinetic energy impact. This is why the planes entered the WTC towers, they had the energy to do it so to speak. Robertson desired the WTC towers to stop a 187 pound of TNT kinetic energy impact in the form of an aircraft. So the impacts on 9/11 were significant they destroyed the fire systems in WTC towers, and they destroyed the insulation on the steel. See
http://i286.photobucket.com/albums/ll116/tjkb/WTCcladdingflying.jpg
The fires systems at this moment of impact are destroyed, damaged and not usable, the fires will not be fought. If this was at night there would be no people like you deniers saying the fires were small and making up lies about the fires; you don't understand sampling you will not understand light. The fire proofing on the steel is destroyed by the impact.

The jet fuel fires had the heat energy of 315 tons of TNT Tony, you need to work on your equal energy calculations you are not doing well in the real world stuff, you should stick with your paranoid delusions.

The fires were the heat energy of 300 to 500 TONS of TNT - what did you get? Did you see how much energy the fires released so you could see how your real-cd-deal was pure BS? You got the impacts wrong by an order of magnitude of 200; failure. You can't get the simple stuff right, no wonder your nut case conspiracy theories never get published and earn the Pulitzer Prize; you just fool people who don't know you are making up lies. Call it lack of knowledge; when they gain knowledge you will be a fraud to them.

No, you wouldn't be the type to say the plane impacts were the equivalent of 1,300 tons of TNT Tony you missed it by a factor of 2000. Do you perceive the world with the same accuracy? The impact of Flight 11 was 7.35 times greater than the WTC design aircraft impact. Ask the chief structural engineer before you make up lies.
The impact of Flight 175 was 11.34 times greater than design. Do the calculation next time.

Which major journals turned down your papers on the WTC?

[dafydd]

Tony, you need to be more precise and do the work first before spewing your own delusional speculation. The impact of flight 11 was 1357 pounds of TNT, not tons. The collapse released 130 TONS of TNT kinetic energy. The impact of Flight 175 was 2093 pounds of TNT kinetic energy impact. Do you want it in joules? 4,380,000,000 joules in the kinetic energy impact. This is why the planes entered the WTC towers, they had the energy to do it so to speak. Robertson desired the WTC towers to stop a 187 pound of TNT kinetic energy impact in the form of an aircraft. So the impacts on 9/11 were significant they destroyed the fire systems in WTC towers, and they destroyed the insulation on the steel. See
http://i286.photobucket.com/albums/ll116/tjkb/WTCcladdingflying.jpg
The fires systems at this moment of impact are destroyed, damaged and not usable, the fires will not be fought. If this was at night there would be no people like you deniers saying the fires were small and making up lies about the fires; you don't understand sampling you will not understand light. The fire proofing on the steel is destroyed by the impact.

The jet fuel fires had the heat energy of 315 tons of TNT Tony, you need to work on your equal energy calculations you are not doing well in the real world stuff, you should stick with your paranoid delusions.

The fires were the heat energy of 300 to 500 TONS of TNT - what did you get? Did you see how much energy the fires released so you could see how your real-cd-deal was pure BS? You got the impacts wrong by an order of magnitude of 200; failure. You can't get the simple stuff right, no wonder your nut case conspiracy theories never get published and earn the Pulitzer Prize; you just fool people who don't know you are making up lies. Call it lack of knowledge; when they gain knowledge you will be a fraud to them.

Tony you missed it by a factor of 2000. Do you perceive the world with the same accuracy? The impact of Flight 11 was 7.35 times greater than the WTC design aircraft impact. Ask the chief structural engineer before you make up lies.
The impact of Flight 175 was 11.34 times greater than design. Do the calculation next time.

Which major journals turned down your papers on the WTC?

All of them?

[BasqueArch]

Tony, you need to be more precise and do the work first before spewing your own delusional speculation. The impact of flight 11 was 1357 pounds of TNT, not tons. ,,, The impact of Flight 175 was 2093 pounds of TNT kinetic energy impact. Do you want it in joules? 4,380,000,000 joules in the kinetic energy impact. ...Robertson desired the WTC towers to stop a 187 pound of TNT kinetic energy impact in the form of an aircraft. So the impacts on 9/11 were significant they destroyed the fire systems in WTC towers, and they destroyed the insulation on the steel. ....

The jet fuel fires had the heat energy of 315 tons of TNT Tony, you need to work on your equal energy calculations you are not doing well in the real world stuff, you should stick with your paranoid delusions.

The fires were the heat energy of 300 to 500 TONS of TNT - what did you get? Did you see how much energy the fires released so you could see how your real-cd-deal was pure BS? You got the impacts wrong by an order of magnitude of 200; failure. You can't get the simple stuff right, no wonder your nut case conspiracy theories never get published and earn the Pulitzer Prize; you just fool people who don't know you are making up lies. Call it lack of knowledge; when they gain knowledge you will be a fraud to them.

Tony you missed it by a factor of 2000. Do you perceive the world with the same accuracy? The impact of Flight 11 was 7.35 times greater than the WTC design aircraft impact. Ask the chief structural engineer before you make up lies.
The impact of Flight 175 was 11.34 times greater than design. Do the calculation next time.

Which major journals turned down your papers on the WTC?



Beachnut Calls Szamboti’s Bluff, Deals Humiliating Smackdown.
Falsers Rush to Comfort Addled Graduate Mechanical Engineer.

[Tony Szamboti]

IIRC Tony's measurements in his jolt paper took the white structure at the northwest corner of the roof as its main point of reference (particularly of the start of the descent), measuring the distance in pixels of the top of this structure and the upper border of the image. The collapse however was already in progress prior to any movement of this structure:

http://img65.imageshack.us/img65/9404/output2.gif

So Tony's measurements begin sometime after the initiation of the collapse on the South Face.

Also because of the tipping of the upper block, the white structure moved in three dimensions -- not simply down but also southward:

http://img405.imageshack.us/img405/2857/aniv.gif

The Sauret footage from the north obscures such movement to the south. Tony's measurements thus do not capture the full three-dimensional movement of the white structure on the roof.

Three dimensional movement of an item does not affect it's vertical drop component, which is what was necessary to measure to determine whether an impulse had occurred.

[Tony Szamboti]

Tony,

What would someone literate in thermoDYNAMICS say about the effect of the difference in thermal conductivity of steel & concrete on the TRANSIENT thermal expansion of the two during the heating phase?

How about the difference in heat capacity & mass of the two?

Gee, Tony. Do you think that perhaps there might have been a couple of competent thermodynamicists who analyzed this correctly? And found out that, in the relatively short period of time during which these assemblies were heated by fire (in any given location) that, FOR THE TRANSIENT RESPONSE during heating, there was inconsequential difference between an analysis that included both steel & concrete thermal expansion and one that ignored the expansion of the concrete.

What do you think?

Tom

Tom, you are being quite presumptuous here. Do you have a reference as to whether the NIST makes a statement that they did an analysis and found that the heating of the concrete would have no effect? I can't find it in the WTC 7 report.

BTW, the field you probably mean here is thermal dynamics not thermodynamics which would not involve thermal conductivity, heat capacity of materials etc.

[Hokulele]

Three dimensional movement of an item does not affect it's vertical drop component, which is what was necessary to measure to determine whether an impulse had occurred.


Ah, here is another reason why you refuse to accept the rotation of the top block at the onset of the collapse. The denial is making more sense with each post.

[rwguinn]

Ah, here is another reason why you refuse to accept the rotation of the top block at the onset of the collapse. The denial is making more sense with each post.
Actually, you are wrong in just about every conceivable way, Hokulele.
It make even less sense as we go...
A vertical component will exist in a rotation, too. So will lateral components.

[Grizzly Bear]

Tom, you are being quite presumptuous here. Do you have a reference as to whether the NIST makes a statement that they did an analysis and found that the heating of the concrete would have no effect? I can't find it in the WTC 7 report.

Looks to me if you're referring to the thermal coefficients of the two materials being similar, wouldn't their responses to thermal changes be the same? It's these similar properties which prevent concrete from fracturing due to differential expansion between it and another type of reinforcing material... and the reason the two (Steel & concrete) are used together in the first place. They respond similarly and it makes the two compatible. What precisely are you expecting the NIST to have found having included it in their analysis?

[Tony Szamboti]

Ah, here is another reason why you refuse to accept the rotation of the top block at the onset of the collapse. The denial is making more sense with each post.

What does it have to do with it? You aren't making sense here.

[Tony Szamboti]

Looks to me if you're referring to the thermal coefficients of the two materials being similar, wouldn't their responses to thermal changes be the same? It's these similar properties which prevent concrete from fracturing due to differential expansion between it and another type of reinforcing material... and the reason the two (Steel & concrete) are used together in the first place. They respond similarly and it makes the two compatible. What precisely are you expecting the NIST to have found having included it in their analysis?

Have you read the NIST WTC 7 report?

[Hokulele]

Actually, you are wrong in just about every conceivable way, Hokulele.


Par for the course.

It make even less sense as we go...
A vertical component will exist in a rotation, too. So will lateral components.


I looked at the two video clips Mangoose had posted and noted the location of the structure Mr. Szamboti was using as a reference and the angle from which Mr. Szamboti's measurements were made. IIRC, the area around which the upper block rotated can make it appear that there is no apparent movement of the reference structure as the displacement from the drop will be visually cancelled out by the displacement from rotation. As Mangoose pointed out, this throws off the timing calculated by Mr. Szamboti.

Only by denying any rotation could Mr. Szamboti's claims as to the timing of the start of the collapse appear to hold.

[Grizzly Bear]

Have you read the NIST WTC 7 report?

Not all of it... point me to the section in question and I'll more than happily have a look.

[BasqueArch]

Three dimensional movement of an item does not affect it's vertical drop component, which is what was necessary to measure to determine whether an impulse had occurred.

Mathematical World Astounded.
Szamboti Proves Descartes Mistaken And Not French -
Three Dimensions Do Not Include Vertical Dimension .

[Tony Szamboti]

Mathematical World Astounded.
Szamboti Proves Descartes Mistaken And Not French - Three Dimensions Do Not Include Vertical Dimension.

No, all I said was that the other two components in the three dimensional movement do not affect the measurement of the third component, which in our case was the vertical component.

Engineers and others who often deal with three dimensional problems understand this.

[BasqueArch]

No, all I said was that the other two components in the three dimensional movement do not affect the measurement of the third component, which in our case was the vertical component.

This should be obvious to anyone with technical savy.

Szamboti Reconsiders. Descartes French After All.
Mathematical World Relieved.

[Tony Szamboti]

Szamboti Reconsiders. Descartes French After All.
Mathematical World Relieved.


It wasn't that I reconsidered at all.

The problem was that BasqueArch Misunderstood and Spoke too Soon

[Newtons Bit]

It wasn't that I reconsidered at all.

The problem was that BasqueArch Misunderstood and Spoke too Soon

His font is way better than yours.

[funk de fino]

Have you read the NIST WTC 7 report?

That's ironic coming from you.

[tfk]

Tony,

Tom, you are being quite presumptuous here. Do you have a reference as to whether the NIST makes a statement that they did an analysis and found that the heating of the concrete would have no effect? I can't find it in the WTC 7 report.


Are you a competent engineer or not?

Why do you need NIST to tell you about the difference in thermal conductivity between steel & concrete? Why the hell do you need NIST to tell you how that conductivity difference will affect the RATE of temp rise in the bulk material for 1/2" thick steel heated on both sides versus 4" thick concrete heated on one side?

Yes, I remember seeing a passing comment in the NIST report explaining that they neglected the thermal expansion of the concrete for the transient analysis. And realizing immediately that it was a perfectly reasonable assumption. Because even tho the beam & concrete may have ultimately arrived at the same amount of thermal expansion after everything equilibrated, there is zero doubt that the steel beams are going to expand so much faster than the concrete, that you may as well consider the thermal expansion of the concrete to be zero.

If you want to go find the comment, be my guest.


BTW, the field you probably mean here is thermal dynamics not thermodynamics which would not involve thermal conductivity, heat capacity of materials etc.


BTW, that was a play on words, emphasizing the "DYNAMICS" portion of the word. I would have thought an ME would have gotten the pun.

Tom

[tfk]

Looks to me if you're referring to the thermal coefficients of the two materials being similar, wouldn't their responses to thermal changes be the same? It's these similar properties which prevent concrete from fracturing due to differential expansion between it and another type of reinforcing material... and the reason the two (Steel & concrete) are used together in the first place. They respond similarly and it makes the two compatible. What precisely are you expecting the NIST to have found having included it in their analysis?

Griz,

The two materials (the steel & the concrete) expand as they heat up. The amount they expand at any given moment is proportional to their coefficient of thermal expansion and their actual temperature at that moment. So, if those two coefficients match, then what you say is right - FOR THE STATIC case. That is, as long as the temperatures of the two components match.

Unfortunately for the WTC7 case, the steel has several factors that cause it to heat up much, much faster than the concrete. The principle factors are:

1. thermal conductivity
2. thermal mass (the mass & heat capacity of the concrete vs. the steel)
3. the thickness of the steel (~ 1/2" thick) vs. the concrete (~ 4" thick)
4. the steel being heated on both sides vs. the concrete heated on one side.

As a result, the steel heats up very quickly, expands very quickly, compared to the concrete. And during this differential transient expansion, the shear studs are fractured.

After the heat eventually soaked into the concrete, then it would have eventually caught up to the expansion of the steel. But the damage to the shear studs connecting the two parts would have been done very quickly.

To get an idea of the difference between the temp performance of the two materials, ask yourself: "Would you prefer to lay for 20 minutes on top of a 1/4" thick piece of steel sitting over a raging fire, or a 4" thick piece of concrete?"

It is very likely that 20 minutes on the concrete will have you barely getting toasty. In about 30 seconds on the steel, you're gonna be starting to fry.

Tom

[rwguinn]

Not all of it... point me to the section in question and I'll more than happily have a look.
What does 7 have to do with rotation of 1 and 2?.
Tony's derail attempt (mis-direction) reported.

[9/11 Chewy Defense]

Szamboti Defeated!
Truth Movement Crumbles!

[tsig]

Three dimensional movement of an item does not affect it's vertical drop component, which is what was necessary to measure to determine whether an impulse had occurred.

So you're of the clakity clack skool.

[tsig]

It wasn't that I reconsidered at all.

The problem was that BasqueArch Misunderstood and Spoke too Soon

Never get into a font war in Asia.

[cmcaulif]

No, all I said was that the other two components in the three dimensional movement do not affect the measurement of the third component, which in our case was the vertical component.

Engineers and others who often deal with three dimensional problems understand this.

There are a total of six components of motion permitted here (though not all may be significant), 3 translational, 3 rotational.

either type can be written in terms of the other type using a coordinate transformation.

[Dave Rogers]

Three dimensional movement of an item does not affect it's vertical drop component, which is what was necessary to measure to determine whether an impulse had occurred.

That's nonsense. The vertical drop component is a component of the three-dimensional movement of the item. Would you like to go away and re-think that, then come back with something that makes sense?

Dave

ETA: Ah, I see you have. I'll leave the above quote in place, though, just to highlight that you mis-spoke rather than Basque Arch misunderstanding.

[Dave Rogers]

There are a total of six components of motion permitted here (though not all may be significant), 3 translational, 3 rotational.

either type can be written in terms of the other type using a coordinate transformation.

And, of course, non-zero values of two of the rotational components will produce different rates of drop for different parts of the undeformed structure, which is the whole point that Tony has repeatedly failed to grasp.

Dave

[Tony Szamboti]

That's nonsense. The vertical drop component is a component of the three-dimensional movement of the item. Would you like to go away and re-think that, then come back with something that makes sense?

Dave

ETA: Ah, I see you have. I'll leave the above quote in place, though, just to highlight that you mis-spoke rather than Basque Arch misunderstanding.

I did not say the vertical component was not a part of the three-dimensional movement, just that it is independent of the other two components and can be measured independently. You should know that.

[Tony Szamboti]

Tony,


Are you a competent engineer or not?

Why do you need NIST to tell you about the difference in thermal conductivity between steel & concrete? Why the hell do you need NIST to tell you how that conductivity difference will affect the RATE of temp rise in the bulk material for 1/2" thick steel heated on both sides versus 4" thick concrete heated on one side?

Yes, I remember seeing a passing comment in the NIST report explaining that they neglected the thermal expansion of the concrete for the transient analysis. And realizing immediately that it was a perfectly reasonable assumption. Because even tho the beam & concrete may have ultimately arrived at the same amount of thermal expansion after everything equilibrated, there is zero doubt that the steel beams are going to expand so much faster than the concrete, that you may as well consider the thermal expansion of the concrete to be zero.

If you want to go find the comment, be my guest.



BTW, that was a play on words, emphasizing the "DYNAMICS" portion of the word. I would have thought an ME would have gotten the pun.

Tom

If you can't show that the NIST did an analysis showing that the heating of the concrete was insignificant then you are being presumptuous.

Let's see an analysis showing the beams would have broken the shear studs if the concrete were heated.

In the case of your use of the word thermodynamics it was the thermo portion which wasn't correct.

[Furcifer]

If you can't show that the NIST did an analysis showing that the heating of the concrete was insignificant then you are being presumptuous.


Analysis of the obvious?

[Grizzly Bear]

Griz,

The two materials (the steel & the concrete) expand as they heat up. The amount they expand at any given moment is proportional to their coefficient of thermal expansion and their actual temperature at that moment. So, if those two coefficients match, then what you say is right - FOR THE STATIC case. That is, as long as the temperatures of the two components match.

Unfortunately for the WTC7 case, the steel has several factors that cause it to heat up much, much faster than the concrete. The principle factors are:

1. thermal conductivity
2. thermal mass (the mass & heat capacity of the concrete vs. the steel)
3. the thickness of the steel (~ 1/2" thick) vs. the concrete (~ 4" thick)
4. the steel being heated on both sides vs. the concrete heated on one side.

As a result, the steel heats up very quickly, expands very quickly, compared to the concrete. And during this differential transient expansion, the shear studs are fractured.

After the heat eventually soaked into the concrete, then it would have eventually caught up to the expansion of the steel. But the damage to the shear studs connecting the two parts would have been done very quickly.

To get an idea of the difference between the temp performance of the two materials, ask yourself: "Would you prefer to lay for 20 minutes on top of a 1/4" thick piece of steel sitting over a raging fire, or a 4" thick piece of concrete?"

It is very likely that 20 minutes on the concrete will have you barely getting toasty. In about 30 seconds on the steel, you're gonna be starting to fry.

Tom

Thanks for the clarification... in case it wasn't obvious beforehand I was getting confused over what you guys were getting at.

[Dave Rogers]

I did not say the vertical component was not a part of the three-dimensional movement, just that it is independent of the other two components and can be measured independently. You should know that.

For God's sake, Tony, just scroll up two posts and what you said is there in black and white!


Three dimensional movement of an item does not affect it's vertical drop component,


Just what do you hope to achieve by telling such obvious lies? You made a mistake; why not just say "OK, I could have worded that better"?

Dave

[rwguinn]

For God's sake, Tony, just scroll up two posts and what you said is there in black and white!
He's right in one way--the vertical can be measured independently.
The rest is totally wrong. It is not independent from the other two (actually, 4 in 3D space), but highly intertwined with them.
Rotation requires at least 2 translational motions.



Just what do you hope to achieve by telling such obvious lies? You made a mistake; why not just say "OK, I could have worded that better"?

Dave
Emotional involvement.
No brakes, can't turn the wheel

[Dave Rogers]

He's right in one way--the vertical can be measured independently.

He's right in what he's now pretending he originally said. His original statement is wrong in wrong sauce with a side order of wrong.

Dave

[rwguinn]

He's right in what he's now pretending he originally said. His original statement is wrong in wrong sauce with a side order of wrong.

Dave
You didn't have to cherry-pick me. I said he was wrong...:drool::(

[cmcaulif]

If you can't show that the NIST did an analysis showing that the heating of the concrete was insignificant then you are being presumptuous.

Let's see an analysis showing the beams would have broken the shear studs if the concrete were heated.

In the case of your use of the word thermodynamics it was the thermo portion which wasn't correct.

Crunch through the numbers and you'll find with equal area of the 4" concrete and the 1/4" steel, the steel heats in the neighborhood of 9 times faster.

I don't see what this has to do with your missing jolt, or the fact that rotational motions affect translational ones.

[BasqueArch]

So you're of the clakity clack skool.



Emotional involvement.
No brakes, can't turn the wheel

... His original statement is wrong in wrong sauce with a side order of wrong.

Dave


Haaa, Nice.

[Newtons Bit]

He's right in one way--the vertical can be measured independently.

Only if you can measure the center of mass. Which he didn't.

Hahaha, cherry pick for me too!

[BasqueArch]

Originally Posted by BasqueArch
Szamboti Reconsiders. Descartes French After All.
Mathematical World Relieved.

It wasn't that I reconsidered at all.

The problem was that BasqueArch Misunderstood and Spoke too Soon


Statement is lame in lame sauce with a side order of lame.


You didn't have to cherry-pick me. I said he was wrong...:drool::(


Originally Posted by rwguinn
He's right in one way--the vertical can be measured independently.

Posted by Newtons Bit
Only if you can measure the center of mass. Which he didn't.

Hahaha, cherry pick for me too!

Come on fellas let's keep it clean.

[tfk]

cm,

Crunch through the numbers and you'll find with equal area of the 4" concrete and the 1/4" steel, the steel heats in the neighborhood of 9 times faster.

I don't see what this has to do with your missing jolt, or the fact that rotational motions affect translational ones.

It's got nothing to due with the rotation, and I apologize for participating in the derail.

Tony, if you want to create another thread or bring this discussion to an existing one, please let me know.

___

Now, back to the issue of jolts:

Why would you not answer my simple questions above, regarding the jolt, Tony? The ones that I had to answer for myself.

Why don't you show me where the answers that I gave are wrong.

Please direct us to a thread that already discusses the "jolt", and not this one that is discussing "rotation".


Tom

[Tony Szamboti]

Only if you can measure the center of mass. Which he didn't.

Hahaha, cherry pick for me too!


The whole issue being discussed here was whether Mangoose's point about the item moving in three dimensions had any bearing on whether the use of this item was valid to measure the vertical progression of the roof of the building.

The item was hard mounted to the roof of the building and would thus be indicative of the movement of the roof and the upper block itself.

[Mangoose]

I don't think my point was correctly grasped. I was not saying that the actual movement in three dimensions invalidates an accurate measurement of vertical descent on one side of the building. My point is that the upper block is a three-dimensional solid and what can be seen on one side is not representative of the complete vertical motion of the solid; on account of the tipping and rotation of the upper block, the roof was falling faster on the South Face than on the North Face. The white object on the roof bears this out, as it initially moves more southward than down. This southward movement is obscured by the vantage point of the Sauret footage. The white object appears stationary whereas it is actually already in motion. This follows from my first point in the post, where I show that the antenna mast was already descending prior to any visible movement of the white object on the roof.

[Tony Szamboti]

I don't think my point was correctly grasped. I was not saying that the actual movement in three dimensions invalidates an accurate measurement of vertical descent on one side of the building. My point is that the upper block is a three-dimensional solid and what can be seen on one side is not representative of the complete vertical motion of the solid; on account of the tipping and rotation of the upper block, the roof was falling faster on the South Face than on the North Face. The white object on the roof bears this out, as it initially moves more southward than down. This southward movement is obscured by the vantage point of the Sauret footage. The white object appears stationary whereas it is actually already in motion. This follows from my first point in the post, where I show that the antenna mast was already descending prior to any visible movement of the white object on the roof.

The short white object is right on the northwest corner of the roof and in this video from the northwest it shows the north wall falling at the same time what can be seen of the west wall is falling. http://www.youtube.com/watch?v=y9-owhllM9k

[A W Smith]

The short white object is right on the northwest corner of the roof and in this video from the northwest it shows the north wall falling at the same time what can be seen of the west wall is falling. http://www.youtube.com/watch?v=y9-owhllM9k

interesting the most of the antenna mast is cropped out of that video tony. Sort of convenient for you to ignore the top of the mast moving before the corner drops. Is that out of willful ignorance to support your fantasy or sheer stupidity?

[Tony Szamboti]

interesting the most of the antenna mast is cropped out of that video tony. Sort of convenient for you to ignore the top of the mast moving before the corner drops. Is that out of willful ignorance to support your fantasy or sheer stupidity?

The important point is what the upper section of the building itself is doing and since the building is visible we should look at the primary source.

[Mangoose]

The short white object is right on the northwest corner of the roof and in this video from the northwest it shows the north wall falling at the same time what can be seen of the west wall is falling. http://www.youtube.com/watch?v=y9-owhllM9k


It is hardly "at the same time". That is the very same video I use to show the antenna mast falling prior to the white device on the roof. And if you actually watch the video carefully, not the crappy quality Youtube one, but the high-quality version on the National Geographic DVD, you can easily see the dust cloud on the 98th Floor on the West Face form a split second prior to the 98th Floor dust clouds on the North Face. In fact, you can see it shoot northward across the West Face to the North Face. I can make an animated GIF video that shows this, but I don't have any time to do this right now. But watch carefully and you will see the northward progression along the West Face. First at the southwest corner of the West Face you see a flame flicker out a window near the 96th Floor or so (this can be compared with the helicopter view of the South Face collapse occurring slightly before this), then the floor above it compresses and/or collapses, and then after this you see the dust cloud form along the 98th Floor from this site and then northward to the North Face.

You can see similar behavior on the East Face in the NBC video of the East Face (see the GIF I posted earlier that shows the East Face dropping a floor before the North Face).

[Mangoose]

Here is the South Face video I mentioned (sped up a little):

http://img382.imageshack.us/img382/8177/asas.gif

You can see the same flame at the southwest corner. The clip ends with the exact moment the 98th Floor dust cloud reached the North Face. Compare with the video you just posted and notice all the activity in the area of the bowed columns on the South Face prior to this event at the southwest corner.

Since the northward formation of the dust cloud along the 98th Floor occurred AFTER this flame flickering at the southwest corner of the West Face at the 96th Floor, this helicopter view of the South Face shows quite clearly that the initiation of the collapse was BEFORE this along the South Face.

And this is the East Face video showing the collapse along the East Face with the upper block tilting to the south:

http://img405.imageshack.us/img405/2857/aniv.gif

[Mangoose]

Okay here is a really rough GIF of the West Face:

http://img260.imageshack.us/img260/4963/r1a.gif

The quality is much, much better with the original so please consult it for full detail. This clip begins with the flaring out of the fire on the 95th Floor (I just checked...this is the correct floor) at the southwest corner. Bear in mind that prior to this moment, the antenna was already descending. Then there is visible activity on the 96 and 97th Floors above the flare-up just north of the southwest corner, looking like it is caving inward and or undergoing some sort of collapse (it is more visible on the original video). And then on the 98th Floor, there is a line of dust clouds that shoot across rapidly northward. While this is happening, the fires on the 104th Floor begin to descend. And about two or three frames later, the white structure on the northwest corner of the roof begins its descent. It starts to fall before the line of dust on the 98th Floor reaches the northwest corner. This clip ends with the moment when the dust begins to be expelled on the 98th Floor on the North Face (you can notice it especially on the changeover).