BigAl
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Clouds don't weigh anything.
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Proposed Design for Progressive Collapse Demonstration
- Thread starter Myriad
- Start date
Clouds don't weigh anything.
I noticed the following:
1. The "white cloud" is a portion of the dust cloud that is highlighted by the sun.
2. The material seen in the white cloud is primarily dust that was already in the air at the beginning of the clip. If you go back and forward over those frames, you can see that the portion of the cloud that has become white by 0:09 is composed mostly of dust that is farther from the tower and falling more slowly, as heavier debris closer to the tower can be seen falling more rapidly. So it is likely that this material was ejected earlier and is relatively lower in density.
3. The position of the white cloud does not mark anything of significance. Being farther from the tower makes its height unclear given the upward camera angle, and the clip does not show when it was ejected nor where it was ejected from. However, other video footage shows the first debris being ejected at the collapse initiation zone, as a result of the upper portion collapsing onto the lower portion. So, the proposition that 20% of the upper mass went anywhere before the collapse started is unsupportable.
4. The analytical models of progressive collapse that I've seen do not suggest that progressive collapse, once initiated, would be arrested if the initial upper mass had been 20% lighter. The excess of energy available far exceeds 20%.
I see nothing in the video, nor in Heiwa's disproven claim of a universal principle, that refutes the experts' conclusion that once the collapse started, what followed was inevitable. The only challenge here (and the topic of the thread) is modeling the phenomenon at a much smaller scale. Heiwa's funny m model, even though his calculations and conclusions about it are wrong, did provide some insight into that problem (the model being scale-independent in certain respects). Do you have anything to contribute on-topic?
Respectfully,
Myriad
Yes, your post #1 is clear and it seems I am the inspiriration behind it. Yes, engineering and math are important to get your design together and I assist you. Layman's terms make things easier for everybody, even experts. Layman's terms are simply easier to understand.
The Heiwa Challenge is an engineering challenge. Just get a structural design together where C crushes A. No differential equations are required. Just elements, nuts and bolts and whatever. Glue?
In another thread I challenge anybody to prove the same thing using math and physics and a piece of paper. It is much more complicated. I cannot prove it myself. So I made it a simple axiom. C cannot crush A. Reason being A crushes C in my simple opinion and world. I have seen many cases like that. Never the reverse.
Just prove the opposite and the Björkman axiom is not valid. Do it by model design + test or with pen + paper. I am convinced it is impossible, you think it is possible. Good luck.
bill smith
Philosopher
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Only observations. Tell me this- where do you place the top of part'A' in relation to the white cloud ?
I don't, for the reasons I already explained.
Please explain the relevance of this line of argument to development of any of the models discussed in this thread or any related models, or take it to another thread.
Respectfully,
Myriad
tsig
a carbon based life-form
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You cannot prove it but you will argue with those that can prove it.
Predictably, you ran from my question about the order of the collapsing floors. Do you really think it matters if C1 contains lawn furniture while C2 contains metal printers' plates? It doesn't, no matter what the incompetent Heiwa tries to pretend. Do you begin to understand that A97 is hit by the entire collapsing mass? What is being ejected in the video narrated by the fraud is mostly pulverized gypsum. Yes, the perimeter columns are falling away, but the weight of thirteen floors is still falling on one floor, a floor that was not designed for such a load.
When do you acknowledge that your pretensions have been exposed? You can't do any calculations and your assumptions are absurd. The twenty, or fifteen, or thirteen falling floors hit ONE floor and crush it, adding it to the total collapsing mass. The process repeats until the entire building has collapsed. You haven't fooled anyone except your mindless echoes, who really don't count.
Then you should restrain from doing any wild speculations.
bill smith
Philosopher
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Myriad, this next video is germane to the developement of your model and the observations made should be accounted for in your calculations in my opinion.
If you watch this fairly clear video in fullscreen you will aee that the 300-foot antenna on top of WTC1 starts collapsing into the building BEFORE there is any other visible movement in the stucture. This must surely mean that something cataclysmic was happening to the support elements for the antenna inside the top portion 'C' PRIOR to collapse onset. Can you speculate in the light of this clear and unavoidable evidence what might have been happening ? And can you model it ?
http://www.youtube.com/watch?v=y9-owhllM9k
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All of which, even if true, is totally unrelated to this thread.
First it was the "white cloud", now it's the antenna.
How long are you going to keep that little game going?
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1. This thread is to assist Myriad designing a structure for The Heiwa Challenge! Thus Myriad shall expose me. And I assist for obvious reasons.
2. Please, 20, 15 or 13 elements spaced a distance apart, cannot simultaneously hit anything! Just one element can hit another ... and the weakest breaks.
3. So such a process cannot be repeated. Objective of The Heiwa Challenge is to repeat it a couple of times. Nobody has managed that. Myriad is trying, though.
4. Purpose is not fool anybody but to educate anybody. That plenty of anybodies were fooled on 9/11 is clear. And some influential ones, like Condoleeza Rice (spelling ??). She is easy to influence. And see, where is she now!
You can't educate anybody because you are incompetent. The collapsing floors have collapsed. No, you don't get it, but notice what you refuse to address. Your confused echo Bill Smith believes that if he's on A97, he's lucky if C1 contains lightweight garden furniture and all the heavy stuff is on the higher floors. You believe that he's safe in any case. Every engineer in the world understands that he is about to get crushed as the ENTIRE mass of thirteen floors falls on him.
Find ONE engineer who takes you seriously, Mr. Horizontal-pulling-force-of-gravity.
Here is another 'structure' that anybody can build. You need 22 coffe cup plates and plenty of sugar lumps.
Clear the kitchen table and put 4 sugar lumps on it in a square. Put one plate on the four lumps and put another four lumps on the plate! Repeat 20 times.
Result? A nice tower of 20 plates supported by sugar lumps. OK, the connections lumps/plates are not fixed but you can glue them.
In this structure the sugare lumps on the table are the highest stressed.
Now you can do plenty of things!! You can drop the 2 extra plates with 4 lumps in between on the tower and see what happens.
Or you can put a little petrol on one plate and arrange a fire so that the sugar lumps melt and ... the plates above drop down.
If all the sugar lumps suddenly fail one after the other and the plates drop on one another due to gravity alone you have managed a design for Progressive Collapse Demonstration.
Clear the kitchen table and put 4 sugar lumps on it in a square. Put one plate on the four lumps and put another four lumps on the plate! Repeat 20 times.
Result? A nice tower of 20 plates supported by sugar lumps. OK, the connections lumps/plates are not fixed but you can glue them.
In this structure the sugare lumps on the table are the highest stressed.
Now you can do plenty of things!! You can drop the 2 extra plates with 4 lumps in between on the tower and see what happens.
Or you can put a little petrol on one plate and arrange a fire so that the sugar lumps melt and ... the plates above drop down.
If all the sugar lumps suddenly fail one after the other and the plates drop on one another due to gravity alone you have managed a design for Progressive Collapse Demonstration.
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This would be equivalent - from previous discussions - to "an ant dropped 2x its body length"
However, an elephant dropped 2x its body length will not have a similar experience to the ant.
Do you accept this analogy, Heiwa?
??? What are you talking about? Twenty elephants on top of one another? Design for Progressive Collapse Demonstration?
You can replace the coffe cup plates (china) by paper play cards or steel plates, if you like, and chose some other type of intermediate supports. The result is always the same.
Scale, Heiwa, scale. An engineer like you should understand this.
Grizzly Bear
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Say for example we have an umbrella shaped shelter that is 10 ft & 10 ft deep with a flat concrete roof 1 ft thick and a single center column having an area of 1ft2.
Concrete is roughly 150 Lbs/ft3, the total load on the column is about 15 kips, and the compressive stress is 15 kips/ft2
Note: 1 kip = 1,000 lbs
Take the same structure and increase the size 3 fold, overall size increases to 30 ft in each dimension; The roof slab would increase in thickness to by 3 fold as well resulting in a slab with about 2700 ft3, and a weight of 405 kips. The area of the center column would increase to 9 ft2. The column stress would be 45 kips, which is three times that of the original smaller structure. In order to effect the same compressive stress , the column area would have to triple to 27 ft2 with column dimension increasing to 5.2 ft on each side.
A 1 ft3 volume of concrete can be loaded with many times it's own weight, however a slab of concrete the size of a building may only support double it's own weight.
Congratulations... you finally learned about the square cube effect
Accept it? He can't begin to understand it. You are attempting to explain basic physics to someone who thinks that gravity doesn't exist and the top twelve floors of a collapsing mass of thirteen floors float in midair as the bottom floor of the mass gently kisses the floor it falls on.