Why a one-way Crush down is not possible

[Newtons Bit]

This is what I was trying to say. When the whole top part of the building starts to fall, what stops it?

Heiwa thinks that friction stops it. Friction with what, I don't know. But... friction! You can stop multi-thousand-pound steel members falling vertically with friction!

 

[bill smith]

This is what I was trying to say. When the whole top part of the building starts to fall, what stops it?

Well it doesn't REALLY start to fall in the sense of 'fall'. There were over 300 columns holding up part C to begin with until the plane severed about 40 perimeter columns and a few core ones. So there were still better than 85% of the columns between the upper part C and the lower part A intact.

 

[twinstead]

There might have been a couple two or three columns weakened by the resulting huge, unfought fires, bill, don't you think?

 

[bill smith]

There might have been a couple two or three columns weakened by the resulting huge, unfought fires, bill, don't you think?

You must have some photographs I haven't seen. Can you post some of them ?

 

[ozeco41]

This is what I was trying to say. When the whole top part of the building starts to fall, what stops it?

Nothing did. Heiwa persists in referring to his model falling by a method which is not analogous to how the WTC towers fell

Heiwa thinks that friction stops it. Friction with what, I don't know. But... friction! You can stop multi-thousand-pound steel members falling vertically with friction!

I don't think Heiwa has commented on how the WTC Towers fell .. I may be wrong.

However the towers fell by the Top Block dropping down so there are Two questions to answer to "disprove" demolition. Those questions go the two event:

1. The initial collapse OR Why did the top block START to fall; AND
2. The global collapse OR why did it continue rather than stop.

Heiwa's claim for his model is correct in that a little bit MAY not destroy a bigger bit. But that is MAY not the exclusive WILL NEVER which Heiwa keeps trying to "sell". AND even there he is wrong on the reason why.

His assumption is that the little bit falls and makes contact between like parts of the big and little blocks. That is the false assumption that most truthers imply even if they do not state it explicitly. Sadly many posters on the "no demolition" side make the same error. Including some of the "big names"

One group of those committing this error assume that the Top Block fell as a sort of homogeneous entity and struck a similar homogeneous entity. As if two blocks of wood were involved.

The others recognise that the falling block and the lower block were more like wire cages but still fell "wire on wire".

The cue word to either of these assumptions is "crushed" or derivatives such as "crushing". Where you see those words look for claims that columns were crushed. The outer tube columns were not crushed - the fell in peeled off sheets (BTW that is true whether or not demolition peeled them off )

There is some but not complete evidence of how the core failed. So we need to think to work out what must have happened to sufficiently robust probability.

AND a point I have not made previously on this forum. One which has not been addressed here to my knowledge. Even if the core had been an infinitely strong solid block the outer floors would still have fallen. (For those who know the structure it is unlikely that the "hat truss" could have held the outer floors of the falling top block)

The reality is that the Top Block fell by wedging inside the outer walls of the lower section. It went past the outer columns. The lower "face" of the falling block struck two areas:

1. The outer tube office space where an overwhelming overload sheared the floor joists off the columns at both ends; AND
2. the core area which, despite all the rhetoric of "extremely strong" was like two halves of a birdcage falling.
   
   Failure of the outer floor area is obvious.
   
   Failure of the core needs a little more thought.
   
   The chance of "wire on wire" (or column on column in WTC) contact was small - at most only a portion of core columns would have got close to the aligned end for end contact needed to transfer axial loads. All the others would have been pushed aside and a few other mechanisms. None of which matters other than they all involved failure modes of much lower strength than the axial compression for which columns are designed.

 

[ozeco41]

You must have some photographs I haven't seen. Can you post some of them ?

There are lots of them out there bill.

try this as a starter: http://www.debunking911.com/collapse.htm

Naturally there is no single photo which shows the lot. But plenty to show that some floors sagged and that many outer columns bowed inwards. That bowing inwards was IMO a basis of for a cascade (or "runaway" or "snowballing") type failure which would also incorporate other modes of failure.

 

[bill smith]

There are lots of them out there bill.

try this as a starter: http://www.debunking911.com/collapse.htm

Naturally there is no single photo which shows the lot. But plenty to show that some floors sagged and that many outer columns bowed inwards. That bowing inwards was IMO a basis of for a cascade (or "runaway" or "snowballing") type failure which would also incorporate other modes of failure.

Which building is this ?
http://www.debunking911.com/columnd.jpg

 

[ozeco41]

Which building is this ?
http://www.debunking911.com/columnd.jpg

The one top right with the circular patterns as your pic is posted is the WinterGarden

This is the layout (courtesy FEMA) I have rotated the plan to match the orientation. The front wall layout of the building WFC2 is clear to identify.

____

 

[FineWine]

Finewine, the floors of the WTC did not hold up the floors above them. It was a floor truss system. The floor truss system meant that individual floors literally braced the external columns to the inner core. This was the tube in tube design, whereby an inner and outer tube took the weight of individual floors but relied on the bracing of the floors to actually hold them together.


This bracing could not stop the massive falling dynamic weight once the upper section started to fall.

Where I'm having trouble with Heiwa is his idea that the collapsing floors slow down, not speed up. Is he saying that I'd be better off jumping out of the window of a very tall building because I would have time to slow down? I'm not trying to make fun of him but how can an engineer think that a falling mass hitting one floor after another, gaining weight and momentum, will slow down and not speed up? Isn't it obvious that the collapsing part of the building weighs more and hits harder with each floor it smashes through? He thinks friction slows it down? Is he joking?

I apologize if everything I'm saying has been said before. I don't understand why this isn't obvious to an engineer.

 

[dtugg]

Where I'm having trouble with Heiwa is his idea that the collapsing floors slow down, not speed up. Is he saying that I'd be better off jumping out of the window of a very tall building because I would have time to slow down? I'm not trying to make fun of him but how can an engineer think that a falling mass hitting one floor after another, gaining weight and momentum, will slow down and not speed up? Isn't it obvious that the collapsing part of the building weighs more and hits harder with each floor it smashes through? He thinks friction slows it down? Is he joking?

I apologize if everything I'm saying has been said before. I don't understand why this isn't obvious to an engineer.

Don't try to make sense of what Heiwa says, it is pretty much impossible. I stopped trying to make sense of him after he started comparing the WTC to stacks of pizza boxes, lemons, sponges, matchboxes, ect. Just appreciate Heiwa for the unintentional comedic genius that he is.

 

[leftysergeant]

What Heiwa posts regarding friction is true in a conventional structure, witrh evenly-spaced vertical elements. The vertical elements absorb the force.

In the towers, there were no internal vertical elements, thus no arresting structure.

He is still comparing it to colliding ships.

 

[ozeco41]

....I apologize if everything I'm saying has been said before. I don't understand why this isn't obvious to an engineer.

I wouldn't want to disillusion you BUT many engineers see things from a narrow focus in parts and lose track of the whole.

Remember "cannot see the forest for all the trees"

And "When up to your arse in alligators it is easy to forget the objective was drain the swamp"

Those engineers need "steering" by engineers managers who don't lose the plot. They enjoy doing detail,

Anecdote:

I was once called on to check design calculation for a series (details not relevant). the things were 20 items with identical layout except the main dimension increased as a series say 90 - 91 - 92-------------118 - 119

The person doing the calculations had spent weeks calculating every one and was proud of it. I looked at the two extremes, 90 and 119, and saw that they were OK and the 18 from 91 to 118 were a waste of time - fell between the extremes. WOW!!!

Said So to the boss.

Mmmm.......mmm not a prudent move EC

The irony was in the original calculation. At the end the man's final comment was "Since they all fall between the 90 and 119 and 119 is worst case we will build them all the same other than that measurement."

Grrrr - could have said it way back and saved weeks of work.

So all same with Heiwa's model - it starts off wrong so stays wrong and does not relate to WTC.

Different to my anecdote which got the right answer but wasted a lot of effort getting there.

Heiwa's modeling is a dead end

And, for the record ozeco BE (Civil, UNSW 1967) and a bit more alphabet soup so I am allowed to criticise engineers.

 

[bje]

What Heiwa posts regarding friction is true in a conventional structure, witrh evenly-spaced vertical elements. The vertical elements absorb the force.

In the towers, there were no internal vertical elements, thus no arresting structure.

He is still comparing it to colliding ships.

I am reminded of this:

A simple method for rating potentially revolutionary contributions to physics.

- 5 points for each such statement that is adhered to despite careful correction.

- 10 points for claiming that your work is on the cutting edge of a "paradigm shift".

 

[Heiwa]

Heiwa's modeling is a dead end

You are just jealous! My model, which is exactly like Mackey's, shows that a one-way crush down of a structure A by a part C of it by gravity is not possible, which is the whole purpose of the model and this thread.

Very succesful model, I have to say. It is live and opens new perspectives.

 

[Heiwa]

What Heiwa posts regarding friction is true in a conventional structure, witrh evenly-spaced vertical elements. The vertical elements absorb the force.

In the towers, there were no internal vertical elements, thus no arresting structure.

He is still comparing it to colliding ships.

No internal vertical elements? How was the structure standing in the first place and what kept the 111 horizontal elements in place?

No, a 3D steel structure always consists of elements in all three dimensions and these elements are held together by joints. Has nothing to with scale or size. And demolishing the structure A by dropping a part C of A on A (C<1/10A) is not possible. Friction assist in this, when elements and joints are broken and broken elements rub against each other.

But if you do not believe me, produce a structure that can demolish itself by gravity by dropping a piece of same structure on it.

 

[Furcifer]

My model, which is exactly like Mackey's, shows that a one-way crush down of a structure A by a part C of it by gravity is not possible, which is the whole purpose of the model and this thread.

Yur funny, you have no model. You have "Heiwa's Conjecture"

 

[ozeco41]

You are just jealous! My model, which is exactly like Mackey's, shows that a one-way crush down of a structure A by a part C of it by gravity is not possible, which is the whole purpose of the model and this thread.

Very successful model, I have to say. It is live and opens new perspectives.

So you admit "is the whole purpose of the model and this thread."

Whether it is "live" could be controversial. And it reveals nothing new.

GREAT to see your clarification. Can we therefore drop all references explicit or by inference to WTC and 9/11

Folks let us Rejoice, Heiwa confirms that his model is not representative of WTC on 9/11.

Discussion of WTC can now move to other threads.

PS Heiwa! What is there to be jealous of in a simple demonstration of basic physics?

 

[bill smith]

The one top right with the circular patterns as your pic is posted is the WinterGarden

This is the layout (courtesy FEMA) I have rotated the plan to match the orientation. The front wall layout of the building WFC2 is clear to identify.
[qimg]http://conleys.com.au/webjref/002.jpg[/qimg]____[qimg]http://conleys.com.au/webjref/FEMA2rightrot.jpg[/qimg]

Thanks. ..Jeez just HOW many buildings went down that day ? They always say 'three skyscrapers' but with this one I count five..

http://www.debunking911.com/columnd.jpg WF2

http://www.drjudywood.com/articles/DEW/dewpics/Image115.jpg Winter Gardens

http://conleys.com.au/webjref/FEMA2rightrot.jpg FEMA layout

 

[ozeco41]

Thanks. ..Jeez just HOW many buildings went down that day ? They always say 'three skyscrapers' but with this one I count five..

http://www.debunking911.com/columnd.jpg WF2

http://www.drjudywood.com/articles/DEW/dewpics/Image115.jpg Winter Gardens

http://conleys.com.au/webjref/FEMA2rightrot.jpg FEMA layout

Yup - at least three lower ones plus damage to the surrounding ones.

As a word of caution be careful with linking some sites - the Judy Wood link is to picture in a file which is a 255k JPG - seveal of those will bog down even 1.5 meg adsl

I deliberately prune mine for size and squeeze to "just good enough" resolution. The FEMA map is only 25k compared with 100s of k's for the originals.

Also a benefit of the one you link from J Wood. Do you see the girders stuck in the WFC building. On the map they look like they were "outfliers" sent 100's of feet further than the others. So a common cl;aim for "explosives".

But it is clear from the Wood's Liked photo that they were merely a couple of bits which got stuck and left behind when a whole swathe of falling over columns wiped past the building. Pulls the rug from under a lot of "explosive projection" claims. Not all but a lot.

Eric C

 

[bill smith]

Yup - at least three lower ones plus damage to the surrounding ones.

As a word of caution be careful with linking some sites - the Judy Wood link is to picture in a file which is a 255k JPG - seveal of those will bog down even 1.5 meg adsl

I deliberately prune mine for size and squeeze to "just good enough" resolution. The FEMA map is only 25k compared with 100s of k's for the originals.

Also a benefit of the one you link from J Wood. Do you see the girders stuck in the WFC building. On the map they look like they were "outfliers" sent 100's of feet further than the others. So a common cl;aim for "explosives".

But it is clear from the Wood's Liked photo that they were merely a couple of bits which got stuck and left behind when a whole swathe of falling over columns wiped past the building. Pulls the rug from under a lot of "explosive projection" claims. Not all but a lot.



Eric C

They say that the Winter Gardens (above) was destroyed by a 4-ton piece that came off WTC1 600 feet away. In that case WF2 must have been quite a distance off too. Why did IT fall down ?