The 9/11 Forum

Major_Tom --- There is a difference between the resistive force, solely vertical, and other expenditures of energy. So I'd take off the vertical lines along the walls. Similarly, there is a difference between the resistive force as we attempt to determine it from the drop of the antenna mast and the ability of some core columns to resist falling apart into mere column members (thus forming the spire). This I would treat as merely random for simplicity. So just a horizontal green line, because I have no way to differential between floors with trusses and the core. In any case, assuming a vertical avalanche, just a short time after the passage of the crushing front, the different materials would be increasingly thoroughly mixed, remains of trusses, lightweight concrete, ordinary weight concrete and floor pans well jumbled together.

On another matter, can I encourage you to determine the length (height laid out) of the massive section of the west wall lying in West Street and into a building at the other end? With a good determination of this number I can more accurately estimate the crush-down time. Jim Hoffman states 14 seconds. I'm getting 15 seconds, which agrees with my (preliminary) estimate of that length. However, you are much better at the PI aspects than I and I'd like a precise number as deterrmined by the photos taken from the air of GroundZero; the match to the seismograph data works for either 14 or 15 seconds so a better detrmination is highly desirable. Thank you.

Dr. G wrote:Heiwa:

I will answer your question with this:

I think you are familiar with the "verinage" demolition of the Balzac (ABC) building in France since it was discussed on this website a few months ago. An upper block of floors of the building was made to drop on the lower part using hydraulic rams, (No explosives - sorry!)

According to your "axiom" this is impossible; so it looks like your axiom has been falsified!

No. In Balzac controlled demolition part C = part A (and not 1/10th of A)! When part C drops on and contacts part A, local forces/pressures produce failures on both parts, &c. Has nothing to do with my axiom (C= 1/10A, &c).

But Balzac is a nice example of what happens when two similar structures (of equal size) comes into contact after one dropping on the other. Both gets damaged. Similar would have happened when WTC1 upper part (part C) contacted lower structure (part A) and when C = 1/10A.

Bazant assumes part C remains intact and impacts part A several (97?) times and that rubble is produced every time of a little bit of part A. To shred part A into rubble takes 10-15 seconds. After that part C is destroyed in a crush up.

NIST assumes that part C apply so much energy at the one only impact that part A (and C) collapses due to strain energy (strength). Very unclear!

Neither process, Bazant and NIST, can be recreated in models or full scale. Reason is that part C is always destroyed prior to A is fully damaged.

David B. Benson wrote:From a variety of simulations, not just mine, the fact that the tower mas per story declined slowly with height makes very little difference. One can hardly tell the difference between a uniform structure and the mass distribution worked out by Greg Ulrich or available from NIST's SAP stuff, now publically available.

Even if G.Urich's data is 100% correct to 5 decimal places we should be getting that information from an OFFICIAL US GOVERNMENT SOURCE in human readable form. I do not comprehend this tolerance and acceptance of BULLSHIT from government agencies on a subject that has Americans dying and killing people in foreign countries.

I am not at all sure that mass declined slowly going up. The towers were designed to sway 3 feet at the top in a 150 mph wind. Imagine the stresses on the steel in the basement with 400,000 tons of building swaying back and forth. That steel had to be held in rigid positions. How much concrete was on each level of the basements? People are always making a big deal of the floor slabs like that is all we are supposed to care about. But lots of places say there were 425,000 cubic yards of concrete in both towers. That comes to 300,000 tons per tower just using the 110 lb type.

So I am not certain how much there was and since the towers were man made objects that had to be designed and documented and since they were destroyed 70 years after the Empire State Building was completed they were hardly cutting edge technology. So where was the BEEF? I mean concrete?

psik

I find it quite amazing that nobody is able to produce a structure of any kind and any size where an upper part C of this structure can crush part A of same structure when dropped on A (C = 1/10 A).

Where is the problem?

psikeyhackr --- Mass certainly declined slowly going up; common sense shows that, but also read NCSTAR1--6D.

The towers were designed, under maximum wind load, not to have more than 60 seconds of arc local deflection; the columns members basically just sat on top of the members below. See NCSTAR1--2A.

David B. Benson wrote:psikeyhackr --- Mass certainly declined slowly going up; common sense shows that, but also read NCSTAR1--6D.

The towers were designed, under maximum wind load, not to have more than 60 seconds of arc local deflection; the columns members basically just sat on top of the members below. See NCSTAR1--2A.

I count from BEDROCK up, not from ground level up. Are you saying there did not have to be a LOT MORE CONCRETE in the foundation then the rest of the building?

I would not be surprised if the concrete did not extend upward a few floors above ground level.

psik

There is a difference between the resistive force, solely vertical, and other expenditures of energy. So I'd take off the vertical lines along the walls. Similarly, there is a difference between the resistive force as we attempt to determine it from the drop of the antenna mast and the ability of some core columns to resist falling apart into mere column members (thus forming the spire). This I would treat as merely random for simplicity. So just a horizontal green line, because I have no way to differential between floors with trusses and the core. In any case, assuming a vertical avalanche, just a short time after the passage of the crushing front, the different materials would be increasingly thoroughly mixed, remains of trusses, lightweight concrete, ordinary weight concrete and floor pans well jumbled together.

The WTC1 spire. There is horizontal bracing between pairs of columns. I estimate the highest horizontal bracing to be about 60 floors off the ground.

This means nothing substantial fell from above it to crush it.

There are many of these horizontal braces in both spires.

large metal pieces from above are not randomly falling anywhere within the footprint.

They are trapped within the perimeter caging but obviously tending toward the chutes and away from the core.

How else could so many horizontal braces between columns have remained unbroken?

Here is a photo in which 2 large sections of perimeter columns are falling away in pairs, their horizontal braces still intact.

http://www.sharpprintinginc.com/911_old/Photo_archives/spire/view%205%20photo%20copy.jpg

(the 2 falling pairs are different from the pairs seen in the first photo)

I must conclude that there couldn't have been much large debris raining down on the region where there were so many column pairs with their bracing intact.


Many spire photos at the link below

http://www.sharpprintinginc.com/911_old/Photo_archives/spire/

Major_Tom wrote:... trapped within the perimeter caging but obviously tending toward the chutes and away from the core.

Thanks for these pix which I had not previously seen! I agree that this small portion of the core was not impacted in a way such as to cause the column splices and some of the beam connections to fail. (I doubt there is any flooring left.) Not clear this contributed any appreciable vertical resistive force slowing the main advance of the crushing front.

Part of the reason for moving away from that section might be the peeling off of the perimeter walls.

Heiwa:

It is interesting, and very telling, that you dismiss the demolition of the ABC Balzac building as not a ligitimate candidate for your "axiom" because it is (according to you) an example of a collapse with M(upper)/M(lower) ~ 0.5. Your axiom applies (according to you) only to collapses with M(upper)/M(lower) = 0.1.

What about a case with M(upper)/M(lower) = 0.15 ?

Is that outside your axiomatic range?

Dr. G wrote:Heiwa:

It is interesting, and very telling, that you dismiss the demolition of the ABC Balzac building as not a ligitimate candidate for your "axiom" because it is (according to you) an example of a collapse with M(upper)/M(lower) ~ 0.5. Your axiom applies (according to you) only to collapses with M(upper)/M(lower) = 0.1.

What about a case with M(upper)/M(lower) = 0.15 ?

Is that outside your axiomatic range?

I have started a thread about it at JREF:

The Heiwa Challenge

It is assumed at JREF 9/11 Conspiracy Theories Forum that a structure will be crushed, if you drop a piece (1/10th) of the same structure on it and that it is quite normal - no conspiracy. So here is the challenge: Prove it!

Conditions:

1. The structure is supposed to have a certain cross area A and height h and is fixed on the ground. The structure is an assembly of various elements of any type. It can be any size!
2. The structure should be more or less identical from h = 0 to h = h, e.g. uniform density, layout of internal elements, etc. Horizontal elements in structure should be identical. Vertical, load carrying elements should be similar and be uniformly stressed due to gravity, i.e. bottom vertical elements may be reinforced or made a little stronger, if required. Connections between elements should be similar throughout.
3. It is recognized that the structure may be a little higher stressed at h=0 than h=h due to uniform density, elements, etc.
4. Before drop test the structure shall be stable, i.e. carry itself and withstand a small lateral impact at top without falling apart. Connections between elements cannot rely solely on friction.
5. Before test 1/10th of the structure is disconnected at the top at h = 0.9 h without damaging the structure.
6. The lower structure, 0.9 h high is then called part A. The top part, 0.1 h high, is called part C.
7. Mass of part C should be <1/9th of mass of part A.
8. Now drop part C on part A and crush part A (if you can! That's the test).
9. In order to easily repeat the test/challenge drop height should be <1.1 h, i.e. C can only be dropped from 2h above ground on A that is 0.9 h high.
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.

Have a try! I look forward to your structures!

Heiwa

---

Dr. G. Re your question M(upper)/M(lower) or C/A one reason for this challenge is to show that the assumption in your BLGB paper, i.e. that M(upper) or C remains intact during crush down or rubble production of A is not possible. When C produces rubble of A - part B - it also produces rubble ot itself at same rate ... and after a while C is gone! Another reason is to show that rubble of a structure cannot crush the same structure.
I can evidently prove this for various structures but as the number of structures are unlimited I have to make it into an axiom.

C/A = 0.1 is just an arbitrary figure to get the challenge started. C/A = 0.5 can evidently produce a bounce (elastic deformation) - depending on structure and drop height. At a certain drop height (energy input) local failures will also be produced apart from elastic deformation of C and A.
At a bigger drop height you can be sure that C (when C/A = 0.1) is destroyed prior to A.
At an even higher drop height (energy input > total strain energy of C+A)) I wonder what will happen? C is definitely destroyed but will A be completely destroyed? Or is the contact energy wasted somewhere else?

In your BLGB paper it is indicated that C (14 stories) initially applies energy enough to crush say 8 stories of A (total 97 stories) and that after that crush down continues for some strange reasons.

According my experience - applying energy that can crush 8 stories - would result in C being reduced to 10 stories and A to 93 stories and then collision would be arrested. If not, more energy is available because C is still moving, C will continue to be shortened, &c, &c. When all stories of C are rubble, the destruction must be arrested. C doesn't exist any more.

Please, explain where I am wrong!

I agree that this small portion of the core was not impacted in a way such as to cause the column splices and some of the beam connections to fail. (I doubt there is any flooring left.) Not clear this contributed any appreciable vertical resistive force slowing the main advance of the crushing front.

It's purpose is to show that, for whatever reason, significant large pieces of debris did not pass that way. You can see the general statistical path all large debris must have taken.

Trapped within the intact perimeter caging but flowing away from the spires.


You only have a 208x208 ft^2 cross-section and we know the large structural metal pieces were a minimum of 36 ft long. They were raining down within the perimeter yet going around whole sections of the core. It is incorrect to see them falling in a statistically random fashion over some crushing front.



About resistance, we are using the term in different ways.

To be very clear, I won't use the term in my graph.

The vertical axis, R(x), should read: "Relative Resilience of structural regions to being crushed by falling debris."

I am trying to show there is a "path of least resistance" which debris actually did follow (within the chute).

The strength of the perimeter initially contains the collapse front. This is why I spike it to a high value (because it was relatively the strongest, most resilient).


Due to a very high spire in WTC1, I must conclude the core had the ability to push debris to a path of lesser resistance (the chute). How else could it have displaced the many core column sections, minimum 36 ft long, which were positioned directly above it before the collapse? This is why I give it higher values than the chute.


David, if we redefine the vertical axis in this way, would your graph still follow the green line?

Part of the reason for moving away from that section might be the peeling off of the perimeter walls.

The debris in the collapse front is trapped within the intact perimeter caging. The caging has not yet split as this collapse front passes. This is visible in many clips. Perimeter splitting and peeling lag behind the debris at the crushing front.

Therefore all this debris in the collapse front was confined to a narrow 208'x208' region. And yet this front totally misses whole sections of the core very high up in the building (and assumably all the way to the ground). The debris above must have somehow been channelled to the chutes.


How much of the core seemed to be bypassed by large falling structural components?

The linked video shows details I've never seen before it's release.

http://www.youtube.com/watch?v=nIZp6aOibiM&feature=channel_page

Please remember that the core is set up basically as an uneven 8 column by 6 column grid.

The video shows that quite a significant portion of the core must have been bypassed. Notice how we see pairs of columns falling off to the left. The visible row of columns must extend at least 2/3rds across the original core along the core's long side.

Excellent post, Major_Tom.

Dr. Benson, does your analysis only divide the timeline about t0, or is there also an early phase that's treated separately?

Edit: Major_Tom - your last video link, the new video from last year, is the one that shows the term 'spire' is misleading. There was a spire, but it was atop a large-ish portion of remaining core. Also, other videos from the proper angle show the true spire to be momentarily quite a bit taller than angles from which it's typically observed and discussed.

A lot of people are making fun of my demonstration because it uses WASHERS though they are not explaining how that invalidates the point. But it has just occurred to me what else could be used for falling masses.

HARD DISK DRIVES!

It should be possible to get dead hard drives really cheap. They are heavy enough to be realistic but large enough to put real supports underneath. A stack of twenty hard drives with one inch supports in between would still come to less than 4 feet and should be rather heavy.

What to use as crushable supports that would still be strong enough for the static load though?

psik

psikeyhackr wrote:A lot of people are making fun of my demonstration because it uses WASHERS though they are not explaining how that invalidates the point.

There's nothing wrong with washers, that's just silly. Consider the source. Knee-jerks where neurons should be.

But it has just occurred to me what else could be used for falling masses.

HARD DISK DRIVES!

Good idea.

What to use as crushable supports that would still be strong enough for the static load though?

Discarded flip-top cell phones? Let the hinge on the top break. Available by the dumpster load, likely you'll be paid to take them and this can fund the hard drive acquisition.

I'm only half joking. Isn't it odd how obsolete and non-functional electronics are not worth the sum of their parts?

Going back to the first sentence of the thread:

David B. Benson wrote:I will eventually suggest two models.

What's the second model?