The Heiwa Challenge

[bill smith]

I would like to introduce my submission for the Heiwa challenge.

Here is my structure:

Fig 1. Top View

[qimg]http://www.internationalskeptics.com/forums/picture.php?pictureid=1023&albumid=194&dl=1241955953&thumb=1[/qimg]

_____

Fig 2. Side View

[qimg]http://www.internationalskeptics.com/forums/picture.php?pictureid=1024&albumid=194&dl=1241955953&thumb=1[/qimg]


The structure that I have in mind will have two towers of post-tensioned concrete flat slabs supported on steel columns. So as not to confuse them in discussion with the WTC towers, I will refer to my structures as the "East Tower" and the "West Tower". My towers will be connected by pour strips. Each tower will be a rectangle of roughly 60' x 110' and 12 stories high. The reason for having two towers is that we can also mimic the lateral progression of failure that happened in WTC7. When the West Tower collapses progressively to the ground (mimicking the Towers), the failure will progress laterally, dragging down the East Tower behind it, just like what occurred in WTC7. Modeling like this gives us a "two-fer".

It is my contention that I will be able to drop just one floor (the 12th) by removing one of its two supports, and that the drop of this floor will result in a total progressive collapse of BOTH towers. Moreover, I contend that this collapse will happen in "near free fall time" (perhaps 5 seconds), and each tower will generally fall within the footprint of its original, standing structure.

In my model, the concrete floors are supported by wedges that are permenently welded to the columns. Figure 2 above shows 7 floors of welded supports in the West Tower, and 8 floors in the East Tower. The 8th thru the 11th floors of the West Tower have "damage", i.e., removed floors, that statically mimics the damaged floors in the WTC towers.

Fig 2 shows the equivalent of one collapsed floor (the 8th) resting on Floor 7. This collapsed floor does not cause the slab-to-column supports to fail at Floor 7. The support wedges are able to support the static load. However, as a result of its collapse, there is now a 2.5 story fall possible if the upper slabs (9/10/11th floor) give way. This situation mimics the 3 story columns that were used in the towers. Since those columns failed as units, then the distance that the floors can fall is equivalent to at least 1 column height.

In order to meet the Heiwa Challenge criteria, there will be 12 total stories of concrete slab supported by steel columns. In my model, only ONE story (the 12th) will fail. When the 12th story fails, it drops only a couple of feet, strikes the 3 floor, closely spaced stack (9th thru 11th floors) and all four floors fall approximately 2.5 stories, striking the 7th story. This leads to a prompt failure of the 7th story supports, and a progressive failure of the entire West Tower to the ground.

At the same time, the failure propagates laterally into the East Tower. This entire structure will also be dragged down to the ground in a total collapse. The time for each Tower to collapse alone will be "near free fall time". The time for BOTH towers to collapse will be approximately 5 - 8 seconds.

Heiwa, do you accept that this assembly meets your criteria?

tom

Will you link Figs 1 and 2 again T. ?

 

[tfk]

Will you link Figs 1 and 2 again T. ?

For you?

no.

If someone else requests it, I'll be happy to.

 

[Heiwa]

I would like to introduce my submission for the Heiwa challenge.


Heiwa, do you accept that this assembly meets your criteria?

tom

Why not? Another challenger! Welcome! The horizontal elements - the slabs - must be permanently connected to the vertical supports and the structure must pass the lateral test.

The wedges introduce a third type of elements in the structure and are apparently connected to the vertical supports or horizontal slabs some way.

You must record the number of connections between separate elements and all elements in the structure part A (both towers) (as 70% of all connections or elements must be broken for a successful crush down).

Tip - calculate the strain energy required to break 70% of all connections or elements of part A and ensure that part A and part C has the available potential energy to break those and, very important, the capability to apply the energy/forces to break the connections or elements of part A during test in the sequence and manner you foresee.

Note that the upper part C should include 10% of all elements in the structure, e.g. one slab, 10% of all supports and wedges, etc.

Good luck!

 

[bill smith]

For you?

no.

If someone else requests it, I'll be happy to.

Calm down T. I'll check back from time to time. Hows that ? I only want to play devil's advocate with your model.

 

[tfk]

Why not? Another challenger! Welcome! The horizontal elements - the slabs - must be permanently connected to the vertical supports and the structure must pass the lateral test.

The wedges introduce a third type of elements in the structure and are apparently connected to the vertical supports or horizontal slabs some way.

You must record the number of connections between separate elements and all elements in the structure part A (both towers) (as 70% of all connections or elements must be broken for a successful crush down).

Tip - calculate the strain energy required to break 70% of all connections or elements of part A and ensure that part A and part C has the available potential energy to break those and, very important, the capability to apply the energy/forces to break the connections or elements of part A during test in the sequence and manner you foresee.

Note that the upper part C should include 10% of all elements in the structure, e.g. one slab, 10% of all supports and wedges, etc.

Good luck!

.

I have, in essence, produced a model of the towers after ONE set of vertical beams in the initial collapse zone (Part D, that you don't recognize) has failed.

There will be 24 columns per tower, located on the intersections of each A thru H line and 1 thru 13 line shown in the Top View (figure 1 above). Each permanent support has two angle bracket at each column which will welded to each column, and support each concrete floor from below. When the steel wedges are used on the upper floors, there will be two wedges per column that will FIRST be loaded (so that they are well seated) and then tack-welded to the column.

I need to be able to simulate floor to column connections that are weakened by BOTH fire temperatures AND column & floor deformations. This is the job of the wedges. The steel wedges are jammed (from below) between the floors and the columns. Regenerative friction causes them to lock into place. The heavier the loads, the harder the wedges lock the floors. Once they have taken up the load of the floors, they are then tack-welded to the columns. This simulates a connection that, while solid, is not quite as strong as the permanent supports. And therefore model the connections that were weakened on the fire floors of the WTC.

In the WTC towers, we had at least 6 stories that were weakened by fire. All of these floors were in danger of failure. If/when they did fail, all of their weight was available as a downward moving mass to propagate a progressive collapse to the ground.

When I start the collapse, I'll be pulling one of the two wedges on the 12th floor. This will cause that floor to drop a couple of feet. This will cause the other 3 closely spaced floor slabs to let go, one after the other. Note that in my model, I am being conservative again by not having the floors "free fall" between these collisions, and thereby gather up lots of momentum. The weight alone will be causing the progressive failure. Then these slabs will fall approximately 2.5 stories onto the 7th floor.

In essence, this is a much LESS challenging failure, because I have eliminated the upper skeleton of Part C, that effectively punches holes in the lower structure by concentrating the weight onto low area "spikes". I am simply providing the weight of the 3 upper stories onto the lower stories. In addition, I am also eliminating the weight of 12 stories of Part C. The point is that, once the upper segments have successfully destroyed the eight stories below, the momentum of the descending mass will be so great that it will automatically go all the way to the ground.

You have said, Heiwa, that it doesn't matter how far the upper segment falls. I'm having it fall ONE column height - 3 stories. (Actually a little less, 2.5 stories). And I am only using the mass of the upper concrete floors. Again, conservative because I have not included the live load / contents of the structure.

Does this model match your requirements?

tom

 

[Heiwa]

.

I have, in essence, produced a model of the towers after ONE set of vertical beams in the initial collapse zone (Part D, that you don't recognize) has failed.

There will be 24 columns per tower, located on the intersections of each A thru H line and 1 thru 13 line shown in the Top View (figure 1 above). Each permanent support has two angle bracket at each column which will welded to each column, and support each concrete floor from below. When the steel wedges are used on the upper floors, there will be two wedges per column that will FIRST be loaded (so that they are well seated) and then tack-welded to the column.

I need to be able to simulate floor to column connections that are weakened by BOTH fire temperatures AND column & floor deformations. This is the job of the wedges. The steel wedges are jammed (from below) between the floors and the columns. Regenerative friction causes them to lock into place. The heavier the loads, the harder the wedges lock the floors. Once they have taken up the load of the floors, they are then tack-welded to the columns. This simulates a connection that, while solid, is not quite as strong as the permanent supports. And therefore model the connections that were weakened on the fire floors of the WTC.

In the WTC towers, we had at least 6 stories that were weakened by fire. All of these floors were in danger of failure. If/when they did fail, all of their weight was available as a downward moving mass to propagate a progressive collapse to the ground.

When I start the collapse, I'll be pulling one of the two wedges on the 12th floor. This will cause that floor to drop a couple of feet. This will cause the other 3 closely spaced floor slabs to let go, one after the other. Note that in my model, I am being conservative again by not having the floors "free fall" between these collisions, and thereby gather up lots of momentum. The weight alone will be causing the progressive failure. Then these slabs will fall approximately 2.5 stories onto the 7th floor.

In essence, this is a much LESS challenging failure, because I have eliminated the upper skeleton of Part C, that effectively punches holes in the lower structure by concentrating the weight onto low area "spikes". I am simply providing the weight of the 3 upper stories onto the lower stories. In addition, I am also eliminating the weight of 12 stories of Part C. The point is that, once the upper segments have successfully destroyed the eight stories below, the momentum of the descending mass will be so great that it will automatically go all the way to the ground.

You have said, Heiwa, that it doesn't matter how far the upper segment falls. I'm having it fall ONE column height - 3 stories. (Actually a little less, 2.5 stories). And I am only using the mass of the upper concrete floors. Again, conservative because I have not included the live load / contents of the structure.

Does this model match your requirements?

tom

First I cannot read your drawings - too small. But it seems your structure will just pancake - horizontal elements may break their connections to the supports and the supports will remain intact. How many elements do your structure consist of? 24 vertical supports, 10-11 horizontal slabs, 240/264 connections/wedges?

Do not forget the lateral test.

Then you cut the supports below the top slab and let it + 24 pieces of support drop ... on the top slab below ... or on the support stubs? What is going to contact what?

If breakage of 24 connections per slab will take place simultaneously due to gravity is not certain. Result may be unsymmetrical and the gravity force(s) will shift out of your required path leaving connections intact.

Suggest you make bigger drawings; then try to visualize the first structural failure(s) at first impact, then check what element(s) get loose, where they move and what failure(s) they will produce, etc, etc.

If the 24 support elements of part A are not broken, then your structure fails the Challenge. Result may only be 10/11 slabs piled up on top of each other on ground, 24 intact support elements falling besides, also on ground, and 240/264 weak connections broken. Actually all support elements are undamaged - just connections are broken.

Reason is that gravity did not apply any load on the vertical supports, just broke the connections between slabs and supports.

But maybe you can come up with some crush down that also breaks the supports in pieces?

 

[GlennB]

If the 24 support elements of part A are not broken, then your structure fails the Challenge. Result may only be 10/11 slabs piled up on top of each other on ground, 24 intact support elements falling besides, also on ground, and 240/264 weak connections broken. Actually all support elements are undamaged - just connections are broken.

My bolding.

When will you stop lying Heiwa? Your conditions are available in the OP ...

10. Structure is only considered crushed, when >70% of the elements in part A are disconnected from each other after test, i.e. drop by part C on A.

Breakage of the elements is not a requirement, just disconnection. Now you're saying that disconnection is not good enough? Shame on you. Lying is bad enough, but lying repeatedly in print, in public, is also very stupid. It's so easy to expose.

 

[tfk]

First I cannot read your drawings - too small. But it seems your structure will just pancake - horizontal elements may break their connections to the supports and the supports will remain intact. How many elements do your structure consist of? 24 vertical supports, 10-11 horizontal slabs, 240/264 connections/wedges?

Do not forget the lateral test.

Then you cut the supports below the top slab and let it + 24 pieces of support drop ... on the top slab below ... or on the support stubs? What is going to contact what?

If breakage of 24 connections per slab will take place simultaneously due to gravity is not certain. Result may be unsymmetrical and the gravity force(s) will shift out of your required path leaving connections intact.

Suggest you make bigger drawings; then try to visualize the first structural failure(s) at first impact, then check what element(s) get loose, where they move and what failure(s) they will produce, etc, etc.

If the 24 support elements of part A are not broken, then your structure fails the Challenge. Result may only be 10/11 slabs piled up on top of each other on ground, 24 intact support elements falling besides, also on ground, and 240/264 weak connections broken. Actually all support elements are undamaged - just connections are broken.

Reason is that gravity did not apply any load on the vertical supports, just broke the connections between slabs and supports.

But maybe you can come up with some crush down that also breaks the supports in pieces?

.

Of course it will "pancake".

What do you think that the Towers did?

Pancake is a progressive collapse to the ground, started by a smaller piece (Part C) destroying a larger part (Part A), one section at a time, where Part C is 1/4th of total structure.

You are the one that said that "broken parts lose their ability to crush down other parts".

What happened to (snicker) Heiwas's axiom: "smaller part cannot crush down bigger part".

Why all the qualifications all of a sudden...?

tk

 

[Heiwa]

.

Of course it will "pancake".

What do you think that the Towers did?

Pancake is a progressive collapse to the ground, started by a smaller piece (Part C) destroying a larger part (Part A), one section at a time, where Part C is 1/4th of total structure.

You are the one that said that "broken parts lose their ability to crush down other parts".

What happened to (snicker) Heiwas's axiom: "smaller part cannot crush down bigger part".

Why all the qualifications all of a sudden...?

tk

The Towers didn't pancake. They were one-way crushed down and this is what the Heiwa Challenge is about.

 

[Heiwa]

My bolding.

When will you stop lying Heiwa? Your conditions are available in the OP ...

10. Structure is only considered crushed, when >70% of the elements in part A are disconnected from each other after test, i.e. drop by part C on A.

Breakage of the elements is not a requirement, just disconnection. Now you're saying that disconnection is not good enough? Shame on you. Lying is bad enough, but lying repeatedly in print, in public, is also very stupid. It's so easy to expose.

Yes, you read the conditions right. Try to disconnect 70% of the elements in part A by gravity only using the pancake method as per pfk. There are 34 elements or so - 24 should be completely disconnected, e.g. all the supports.
For that all 240 connections must be broken. Just do that!

 

[tfk]

The Towers didn't pancake. They were one-way crushed down and this is what the Heiwa Challenge is about.

.

I am NOT talking about "collapse initiation". I am talking about the collapse propagation.

Please provide YOUR distinction between "crushed down" and "pancaked".

tom

 

[bill smith]

.

I am NOT talking about "collapse initiation". I am talking about the collapse propagation.

Please provide YOUR distinction between "crushed down" and "pancaked".

tom

As I see it a ' pancake' collapse is one where the floors fall like s series of spaced records on a spindle. One breakiing the next off the spindle from he top dpwn. You end up with an upright spindle and a stack of floors around it at the bottom. A 'Crush Down' is a sequence in which the spindle is also somehow crushed floor-by-floor from the top down leavng only wreckage on the ground.

 

[GlennB]

As I see it a ' pancake' collapse is one where the floors fall like s series of spaced records on a spindle. One breakiing the next off the spindle from he top dpwn. You end up with an upright spindle and a stack of floors around it at the bottom. A 'Crush Down' is a sequence in which the spindle is also somehow crushed floor-by-floor from the top down leavng only wreckage on the ground.

Not a totally bad description, imo, though you're showing your age I would say. What with stacked vinyl on a record player, and all.....

Heiwa, however, is utterly fixated* on the exact terminology of "crush-down" models that were never intended to describe the actual collapse mechanism but merely to analyse a limiting case, i.e. that most favourable to collapse arrest.

* to the extent of offering $1,000,000 of his own money.

 

[tfk]

As I see it a ' pancake' collapse is one where the floors fall like s series of spaced records on a spindle. One breakiing the next off the spindle from he top dpwn. You end up with an upright spindle and a stack of floors around it at the bottom. A 'Crush Down' is a sequence in which the spindle is also somehow crushed floor-by-floor from the top down leavng only wreckage on the ground.

Ah, you think the survival of the spindle distinguishes the two...?

I'll wait for Heiwa's response. Perhaps it'll make more sense.

Then again...

 

[bill smith]

Ah, you think the survival of the spindle distinguishes the two...?

I'll wait for Heiwa's response. Perhaps it'll make more sense.

Then again...

I think you said this in a recent post. 'Of course it will "pancake". So how about you describe what you mean by 'pancaking' considering that NIST ruled out the 'pancake effect'

 

[phunk]

I think you said this in a recent post. 'Of course it will "pancake". So how about you describe what you mean by 'pancaking' considering that NIST ruled out the 'pancake effect'

No, what NIST ruled out is pancaking of the floors being the initial trigger of the global collapse.

 

[bill smith]

No, what NIST ruled out is pancaking of the floors being the initial trigger of the global collapse.

Pancaking is a floor dropping on a floor and then those two dropping on the floor below etc all the way down. A Crush Down is an overbearing weight on top crushing everyhing in it's path as it comes to it. So do NIST support pancaking ?

 

[BigAl]

Pancaking is a floor dropping on a floor and then those two dropping on the floor below etc all the way down. A Crush Down is an overbearing weight on top crushing everyhng in it's path as it comes to it. So do NIST support pancaking ?

So what? Do you claim that any differences between of any of the theories for exactly how fire caused the WTC towers to collapse can be explained by the addition of man-made demolition charges?

 

[bill smith]

They say that the plane hat hit WTC1 weighed one-half of one tenth of one percent of the weight of the building. Can you believe that the impact caused the 500,000 ton building to sway back and forth for four minutes ? Incredible.

 

[Newtons Bit]

They say that the plane hat hit WTC1 weighed one-half of one tenth of one percent of the weight of the buildng. Can you believe that the impact caused the 500,000 ton building to sway back and forth for four minutes ? Incredible.

You really don't understand much about dynamics do you?

The WTC had a period of about 11seconds. Which means that if some force caused the building to displacement some distance it would take 11 seconds for the building to cycle through maximum displacement and then back to it's original displacement.

The structure will then continue vibrating, though each cycle will have a maximum displacement reduced by the damping of the structure. For the WTC, the damping ratio is about 3% for elastic displacements of the moment frame.

It takes quite awhile to damp out this much motion.

I know you'll never do it, but I still recommend that you go get a very fundamental education in physics and engineering. This stuff is trivial. Pretending to know something about it when you obviously don't must be incredibly embarrassing for you. Though, like most truthers, I don't think shame is an emotion you're vulnerable to.