OOS Collapse Propagation Model

[ozeco41]

...As I've said a few times, I'm not sure the inclusion has helped matters, but the base point of the inclusion, imo, is simply to highlight that ROOSD does not prove MIHOP, nor does it disprove MIHOP. It simply describes a gravity driven primary mode of destruction. ROOSD is post-initiation, leaving initiation as a blank space. Indeed the biggest remaining hurdle with validating ROOSD in full is determining the sequence of events leading to the initiating state, ie how enough mass became separated from the structure to invoke ROOSD. The study is offered to both *sides* with the intention of reducing spurious claims of floor-by-floor nuke-a-booms on one hand and focus on initiation on the other. A significant issue with initiating scenarios such as that proposed by NIST is that such does not provide a mechanism for supply of that mass early enough.

Detailed thoughts on that last point very welcome.

I do not see how you can be so assured that the NIST explanation 'does not provide a mechanism for supply of that mass early enough'. I do not share that assurance but it is likely that I approach the analysis from a different perspective than you.

As you will be aware I strongly advocate identifying the mechanism or model under discussion before attempting to apply the maths to it. If we go the other way we run the risk of having fine looking maths which, on closer examination, does not fit to the realities of what actually happened.

In analysing Twin Towers collapses I have used as the boundary between 'initiation' and 'progression' that brief period when the top block starts moving downwards. That definition is probably too loose by your standards and preferred methods. I may need to add 'all' as in 'when all the top block starts moving downwards'.

Now, however the initiation phase gets us to that point, from my perspective a key aspect of that point is that all columns have failed or are failing and there is no axial end for end contact between column parts resisting the falling weight with anything like the original designed strength of the column. Sure the interface between top block, lower tower and 'starting to collect rubble' is one confused mess but that does not change the validity of my previous claim.

And at that stage, allowing for all its inherent flexibilities and the load balancing via the hat truss, the full weight of the falling block is available to be shared among whatever bits of top block impact on whatever bits of lower tower.

Now in the interest of brevity I won't attempt to describe all the possible types of interactions (Never could define all of them anyway. ) But the three main ones are:

• Interactions of the outer tube columns. Two main possibilities:
  1. If the outer tube columns of the top block pass inside the outer tube of the lower tower the falling top block columns impact on a floor area with force that is overwhelming and shear off that lower floor; HOWEVER
  2. If the top block outer tube columns fall outside the lower tower then the outer tube of the lower tower will impact the underside of the next floor up in the top block and shear off that floor) (BTW so much for "crush down before crush up" in the real world. )
• Interactions floor area on floor area. Despite all the mess of rubble and bent bits in the impact and fire zone the dominating aspect will be that a floor lands on a floor and one or both will be sheared off. And the available weight/energy to achieve that is overwhelming.
• Core landing on core. The resistance resulting from the interaction will be mainly from horizontal beam landing on horizontal beam. Yes multiple other possibilities - out of vertical column impacts beam and gets shoved more out of vertical - vice versa or the other way up. Bottom line being that amid all those possibilities the horizontal beam on horizontal beam is the one to offer most resistance after all the other glancing blows have passed. So the overwhelming falling weight on the core shears off the horizontal beam.

Now there are numerous bold assertions in that in the interest of brevity. And what really happened would be enormously complicated.

And the boundary of 'initiation' to '(start of) progression' is as per my initial premise. And none of it depends on NIST.

So what is it about the NIST explanation which leads you to say 'not enough mass early enough'?

 

[femr2]

I do not see how you can be so assured that the NIST explanation 'does not provide a mechanism for supply of that mass early enough'.

It depends upon how far from the actual NIST description you are prepared to stretch their mechanism. I'll go into a little more detail in a mo.

I do not share that assurance but it is likely that I approach the analysis from a different perspective than you.

Quite possibly. My statement is based upon close inspection of the development of the SW crush front for WTC1, which develops very early and reaches effective terminal velocity about 4s after release.

The issue pivots upon the amount of mass required to allow sustained ROOSD propogation, and the requirement for that mass to be separated from the remaining portions of the rapidly fragmenting upper block (yeah, that ol' chestnut).

As you will be aware I strongly advocate identifying the mechanism or model under discussion before attempting to apply the maths to it. If we go the other way we run the risk of having fine looking maths which, on closer examination, does not fit to the realities of what actually happened.

The statement is based upon observable behaviour from video footage, and the conditions required for initiating sustained ROOSD.

In analysing Twin Towers collapses I have used as the boundary between 'initiation' and 'progression' that brief period when the top block starts moving downwards. That definition is probably too loose by your standards and preferred methods. I may need to add 'all' as in 'when all the top block starts moving downwards'.

Yes, I'm looking at more specific features.

Now, however the initiation phase gets us to that point, from my perspective a key aspect of that point is that all columns have failed or are failing and there is no axial end for end contact between column parts resisting the falling weight with anything like the original designed strength of the column. Sure the interface between top block, lower tower and 'starting to collect rubble' is one confused mess but that does not change the validity of my previous claim.

Again the issue is a mechanism which releases enough mass early enough for the observable development of the SW crush front, not a more generalised approach.

Now in the interest of brevity I won't attempt to describe all the possible types of interactions (Never could define all of them anyway. ) But the three main ones are:

• Interactions of the outer tube columns. Two main possibilities:
  1. If the outer tube columns of the top block pass inside the outer tube of the lower tower the falling top block columns impact on a floor area with force that is overwhelming and shear off that lower floor; HOWEVER
  2. If the top block outer tube columns fall outside the lower tower then the outer tube of the lower tower will impact the underside of the next floor up in the top block and shear off that floor) (BTW so much for "crush down before crush up" in the real world. )

• 
  Have you looked at MT's perimeter *kick-out* details ?
  
  Per-face details for which perimeter sections pass in front of/behind each other has been documented.
  
  And, yes, perimeter stripping does provide a mechanism for *dumping* mass.
  
  

  So what is it about the NIST explanation which leads you to say 'not enough mass early enough'?

  
  I'll have to gather some details to clarify, but one issue is driven by the question...
  
  How much mass is required to initiate sustained ROOSD ?
  
  1 floor ? 3 floors ? 10 ?
  
  Various estimates have been performed, taking account of documented load capacities, FoS, etc, along with 1D step-wise slab model simulations using various initial masses.
  
  From my outline calcs I'd estimate at least 3 full OOS floor masses are required.
  
  The timing between the observable start of SW crush front propogation and release is very short.
  
  If we have to wait for floor slabs to impact before mass is released, it takes too long.
  
  Bit of a rough description, but I'll gather some additional details.
  
  I'll add that the ROOSD model needs implementing before I'll be fully confident in the initiating mass requirements.
  
  ETA: So perhaps *fully confident( is not quite what I'm saying, but getting enough free mass available early enough is a problem without floor masses detaching in full very early on...which doesn't flow at all naturally from the NIST initiating mechanisms.

 

[Major_Tom]

And at that stage, allowing for all its inherent flexibilities and the load balancing via the hat truss, the full weight of the falling block is available to be shared among whatever bits of top block impact on whatever bits of lower tower.

Now in the interest of brevity I won't attempt to describe all the possible types of interactions (Never could define all of them anyway. ) But the three main ones are:

• Interactions of the outer tube columns. Two main possibilities:
  1. If the outer tube columns of the top block pass inside the outer tube of the lower tower the falling top block columns impact on a floor area with force that is overwhelming and shear off that lower floor; HOWEVER
  2. If the top block outer tube columns fall outside the lower tower then the outer tube of the lower tower will impact the underside of the next floor up in the top block and shear off that floor) (BTW so much for "crush down before crush up" in the real world. )
• Interactions floor area on floor area. Despite all the mess of rubble and bent bits in the impact and fire zone the dominating aspect will be that a floor lands on a floor and one or both will be sheared off. And the available weight/energy to achieve that is overwhelming.
• Core landing on core. The resistance resulting from the interaction will be mainly from horizontal beam landing on horizontal beam. Yes multiple other possibilities - out of vertical column impacts beam and gets shoved more out of vertical - vice versa or the other way up. Bottom line being that amid all those possibilities the horizontal beam on horizontal beam is the one to offer most resistance after all the other glancing blows have passed. So the overwhelming falling weight on the core shears off the horizontal beam.

Now there are numerous bold assertions in that in the interest of brevity. And what really happened would be enormously complicated.

And the boundary of 'initiation' to '(start of) progression' is as per my initial premise. And none of it depends on NIST.

So what is it about the NIST explanation which leads you to say 'not enough mass early enough'?

Yes on the perimeter sheets. That has been observed.

I think of the core columns as "spearing" flooring. They act as spears.

If columns can puncture flooring, the concept of "block" or the block mechanics of Bazant have no meaning. The Bazant mechanics depend on the rubble (magic) "zone B". This buffers top from bottom, but it is an unphysical idea when the realities of floor slabs and columns puncturing the thin slabs are considered.

WIth spearing or puncturing, the main interaction has to be floor vs floor.


Not enough mass: This is a complicated issue. Measurements of progression along the WTC1 SW corner show very rapid early movement quickily leading into a terminal velocity state all the way down.

The earliest movement is surprisingly rapid. More will be said as more information is available.

 

[Major_Tom]

This is a great way to visualize the ROOSD process:

The ROOSD pathways are obvious. If a ROOSD "avalanche" starts with sufficient destructive force, due to the highly repetitive structure of OOS flooring, what can stop it until hitting earth?

You can see the only discontinuities are the red mechanical room floors and the lower escalator floors.


This type of process strips the perimeter from the core, leaving both unsupported by anything but themselves.

The perimeter can't stand alone and "peels" outward in large pieces. The core is left standing.

 

[Major_Tom]

Here is a list of the type of flooring around and just below the aricraft impact zones.

WTC1 on left, WTC2 on right

Notice how WTC1 has all simple repetitive flooring of an identical structure around and just below the collapse zone.

Once ROOSD starts, what will stop it? And it is a highly controlled process, confined within the perimeter.

 

[ergo]

If what you describe is possible, it still would not be achievable in the time frame we witnessed. Nor would it pulverize everything beyond recognition. Where are the floor pans, for example, in the debris pile? Where are the filing cabinets? The computers? The toilets?

 

[Dave Rogers]

If what you describe is possible, it still would not be achievable in the time frame we witnessed.

Please show us the calculations by which you arrive at this conclusion.

Nor would it pulverize everything beyond recognition. Where are the floor pans, for example, in the debris pile?

Visible, as large compressed lumps of debris formed from multiple floors.

Where are the filing cabinets? The computers?

Crushed flat. The ones lower down in the structure had most of the weight of rubble crash into them at high speeds. The ones further up crashed into the rubble at very high speeds.

But all this is quite subtle stuff compared to the stunning obviousness of the idiocy of the final question.

The toilets?

Because porcelain is just so damned indestructible.

Dave

 

[W.D.Clinger]

experiment complete, ergo...

The toilets?

Because porcelain is just so damned indestructible.

ergo dropped loads of stuff into his without breaking it much at all.

 

[twinstead]

Okay, ergo, now the arguments from simple incredulity are getting a little out of hand.

 

[carlitos]

Now?

 

[twinstead]

Now?

Touché

 

[ProBonoShill]

Now?

Touché

He's doing Poe, I'm convinced of it, no one is that idiotic.

 

[Major_Tom]

Ergo, the mechanics are not proven and need to be studied in more detail.


Beam flooring at the mechanical floor levels

This is called "type 12" flooring in the list in my last post. FLs 75 and 77 (lower escalator floor) are both type 12 flooring. These is about the only predictable structural discontinuities for a ROOSD process that we can identify.


Types and timings of ejections from these levels can help us understand details of a theorized ROOSD progression. It is important to look at them in detail.

The lower pair of ejections come from fls 77 and 75.


Venting system on the mechanical fls:

 

[Major_Tom]

The 77th fl ejection begins sooner than what the naked eye can detect.

In the flowing clip, we find the earliest 77th fl ejection becomes visible during the collapse initiation sequence:

http://www.youtube.com/watch?v=acTcwA_YHuA

 

[femr2]

Beam flooring at the mechanical floor levels

Still a puzzle for continued ~linear crush front progression.

Perhaps the explanation is that the core comes into play.

 

[beachnut]

Ergo, the mechanics are not proven and need to be studied in more detail.


Beam flooring at the mechanical floor levels



This is called "type 12" flooring in the list in my last post. FLs 75 and 77 (lower escalator floor) are both type 12 flooring. These is about the only predictable structural discontinuities for a ROOSD process that we can identify.


Types and timings of ejections from these levels can help us understand details of a theorized ROOSD progression. It is important to look at them in detail.


The lower pair of ejections come from fls 77 and 75.


Venting system on the mechanical fls:

What does this nonsense have to do with Conspiracy theories on 911? Please explain why and how this is related to your CD delusion; can you explain?

 

[Major_Tom]

Beachnut, can you see the 77th floor become pressurized during the collapse initiation 20 floors above? How does that happen?


Femr, good point.

In the core remnant, CC501 (CC= core column) and 508 temporarily survived as the tallest 2 columns.

CC508 falls off quickly to the east with CC608. CC501 is seen below:

My calculations place the top of that column at fl 77, the lower escalator floor. Notice there are only 11 "bumps" representing floor connections on the column, while the large, large majority of columns span 3 floors. This means that one column section covers only 2 floors (or you'd have 12 "bumps"). This happens only at fls 41 to 43, and fls 75 to 77, meaning that the column section going from 75 to 77 is in that uppermost column section seen in the image.

Also, anyone can look for uneven spacing in the floor connections on CC501. You will notice the spacing is wider between the top 3 floor connections, meaning the top column section welded to the very top of the tallest column very well could be the fl 75 to 77 column section.

There is a way to measure this to the floor using video. If you want to know more I'll show you on the 9/11 forum and the results can be presented here.


Concerning CC508, video shows it is the same height as CC501 until it fell to the east.

 

[Major_Tom]

I'll give another example. Consider the theory that these ejections are just random "farts" caused by the action of a great "piston".

Why the pattern if random?

 

[ProBonoShill]

Beachnut, can you see the 77th floor become pressurized during the collapse initiation 20 floors above? How does that happen?


Femr, good point.

In the core remnant, CC501 (CC= core column) and 508 temporarily survived as the tallest 2 columns.

CC508 falls off quickly to the east with CC608. CC501 is seen below:

[qimg]http://www.sharpprintinginc.com/911/images/photoalbum/16/view_4.jpg[/qimg]

My calculations place the top of that column at fl 77, the lower escalator floor. Notice there are only 11 "bumps" representing floor connections on the column, while the large, large majority of columns span 3 floors. This means that one column section covers only 2 floors (or you'd have 12 "bumps"). This happens only at fls 41 to 43, and fls 75 to 77, meaning that the column section going from 75 to 77 is in that uppermost column section seen in the image.

Also, anyone can look for uneven spacing in the floor connections on CC501. You will notice the spacing is wider between the top 3 floor connections, meaning the top column section welded to the very top of the tallest column very well could be the fl 75 to 77 column section.

There is a way to measure this to the floor using video. If you want to know more I'll show you on the 9/11 forum and the results can be presented here.


Concerning CC508, video shows it is the same height as CC501 until it fell to the east.

What does this nonsense have to do with Conspiracy theories on 911? Please explain why and how this is related to your CD delusion; can you explain?

Thanks in advance.

 

[beachnut]

I'll give another example. Consider the theory that these ejections are just random "farts" caused by the action of a great "piston".

Why the pattern if random?

Your silent CD explosives lie is showing.

You see patterns and have the CD delusion. What is new, after 9 years of complete failure, you have failed to push your CD theory past the fantasy it is.

Why do you insist on posting proof of NO CD? Good job debunking 911 truth's CD fantasy. Keep up the failed work, only a few can do it as well as you and Gage.