When?, Where?, What?
Why a one-way Crush down is not possible
- Thread starter Heiwa
- Start date
- Status
When?, Where?, What?
aggle-rithm
Ardent Formulist
So, at which college did you study to be a troll?
Here is an example of how total collapse can be generated by less than 1/20th of the total weight of a structure:
1. Get 20 Pizza boxes and stack on top of each other.
2. Tape together the sides with a few vertical lines of scotch tape.
3. cut each side vertically into 4, starting at each corner. Add vertical tape to stick the columns together
4. cut out all horizontal cardboard (the floors), and then replace them sticking them back in position with tiny amounts of glue, that is only just able to support the self weight of 1 piece of cardboard.
5. drop the top horizontal piece.
So what happens.
1. the top piece falls and hits the next piece.
2. and because the glue is only strong enough to support one piece of cardboard the next piece falls...
3 and so on, until all the horizontals have fallen
4. at some point during the collapse the columns, the vertical emlements fall down. The columns will become unstable because they have lost the lateral restraint of the floor thro the glue. The columns will not be able to support their own weight as a single skin of cardboard 20 pizza-boxes tall. The columns will tend to fall outwards because the air is pushed out of the boxes by the collapse, and pushes out the outside walls.
Interestingly, the floors will collapse at essentially free-fall speed as they pancake, because the glue offers no real resistance and is massively overloaded, even after the first impact (200% of design load plus impact force to bring it to about 300% of design). The columns will be slower to fall, and will tend to fall radially out from the middle.
You see the collapse does not have to crush the columns, and if you look at the photos of the pile of debris on WTC 1 and 2 you will see lots of straight pieces. These pieces did not crush and did not provide resistance to crushing which is why WTC 2 fell quickly, in about 14.5 seconds. There was not a lot of resistance to collapse, it fell at 40%g, which means that 40% of the potential energy was converted to kinetic energy, and 60% of the energy was absorbed in the "crush".
So as most engineers knew, Heiwa's theory is neither relevant nor correct. Poor guy has spent several thousand postings trying to justify this nuts.
Justin39640
Illuminator
- Joined
- May 22, 2009
- Messages
- 4,202
you actually made a pizza box building? lol
i really hope you made a video
i really hope you made a video
Tony Szamboti
Illuminator
- Joined
- Jun 2, 2007
- Messages
- 4,976
Here is an example of how total collapse can be generated by less than 1/20th of the total weight of a structure:
1. Get 20 Pizza boxes and stack on top of each other.
2. Tape together the sides with a few vertical lines of scotch tape.
3. cut each side vertically into 4, starting at each corner. Add vertical tape to stick the columns together
4. cut out all horizontal cardboard (the floors), and then replace them sticking them back in position with tiny amounts of glue, that is only just able to support the self weight of 1 piece of cardboard.
5. drop the top horizontal piece.
So what happens.
1. the top piece falls and hits the next piece.
2. and because the glue is only strong enough to support one piece of cardboard the next piece falls...
3 and so on, until all the horizontals have fallen
4. at some point during the collapse the columns, the vertical emlements fall down. The columns will become unstable because they have lost the lateral restraint of the floor thro the glue. The columns will not be able to support their own weight as a single skin of cardboard 20 pizza-boxes tall. The columns will tend to fall outwards because the air is pushed out of the boxes by the collapse, and pushes out the outside walls.
Interestingly, the floors will collapse at essentially free-fall speed as they pancake, because the glue offers no real resistance and is massively overloaded, even after the first impact (200% of design load plus impact force to bring it to about 300% of design). The columns will be slower to fall, and will tend to fall radially out from the middle.
You see the collapse does not have to crush the columns, and if you look at the photos of the pile of debris on WTC 1 and 2 you will see lots of straight pieces. These pieces did not crush and did not provide resistance to crushing which is why WTC 2 fell quickly, in about 14.5 seconds. There was not a lot of resistance to collapse, it fell at 40%g, which means that 40% of the potential energy was converted to kinetic energy, and 60% of the energy was absorbed in the "crush".
So as most engineers knew, Heiwa's theory is neither relevant nor correct. Poor guy has spent several thousand postings trying to justify this nuts.
Nice try, but there are a few serious problems with your model.
It seems the floors in the twin towers were able to statically withstand the weight of 11 additional floors. Don't take my word for it. The NIST says it right in their Dec. 2007 FAQ on the collapses. Read question 1 at the link below.
http://wtc.nist.gov/pubs/factsheets/faqs_12_2007.htm
Taping the columns together vertically probably isn't too realistic either, as it decreases the area of restraint and reduces the moment needed to cause buckling. There should be glue between the bottoms and tops of adjoining box's columns also. The glue here should be sufficient to ensure the original tensile strength and stiffness of the cardboard is maintained.
It doesn't sound like you use anything to provide for the spandrel beams either. They were not insignificant and were about 40% of the height of the columns. If the pizza boxes are 1.75 inches high you should put .75 inch high horizontal bands of thinner cardboard around the perimeter of each pizza box which is glued to each vertical column on that pizza box.
It looks like you are going to have to add a lot more glue and some additional cardboard for the spandrels to make a realistic model. If you do it this way let us know how it works then.
Last edited:
Does this mean you support the failed ideas of Heiwa? Heiwa's ideas are proved wrong on 911. Your realcddeal is a lie and pure delusion. Your lack of evidence is 7 years, 9 months and 12 days old. Did you misplace your evidence? Don't you find Heiwa's failure to understand gravity really sad?
Please if you are supporting Heiwa's idea on this, state or present the hundreds if not thousands of pages of support and calculations.
Having started this thread - see #1 - it seems nobody has managed to demonstrate that a small part C of a steel/composite structure can one-way crush down the remainder, part A, of the same structure below when dropped on A only by gravity. Reason is that part C cannot apply the required energy on A without destroying itself.
Bazant, Seffen, Mackey, NIST, BLGB, etc., suggest that it is possible/will happen, if (!!!) part C is first compressed into one solid, rigid, indestructible mass, but it is not realistic at all. Upper part C is in fact much weaker than part A below.
This is quite basic even if not taught in structural design/analysis courses of intact structures. The advanced course - structural damage analysis - is not too difficult; the structure is locally damaged and you see if more local failures will occur and you establish the path of failures through it. NIST failed to do that with WTC 7.
The very advanced course - two structures collide and damage each other - is even more complex but still understandable.
If one structure is much stronger than the other, the latter is crushed.
If both structures are of similar type, BOTH structures are damaged, and you have to consider the size of each part. You'll soon learn that the smaller part cannot one-way crush down the bigger part.
It is quite sad that NIST cannot find any reference proving even the existence of a structural one-way crush down prior/after 911. They have found some structures collapsing when supports at the bottom are removed, etc, etc, but that is something else. Evidently the table may drop if you remove the legs or a pile of pizza boxes will drop if you remove the bottom box. But try to one-way crush a pile of pizza boxes by dropping other pizza boxes on the pile! It doesn't work.
The "challenge" involved meeting Heiwa's conditions. BlueSky has done this.
Whether or not his taped-up pizza boxes are a reasonable representation of WTC 1+2 is irrelevant.
It's amazing that you can't learn a thing. You're still trying to paper over your staggering lack of comprehension by telling silly lies. Nobody in the world regards the collapsing floors as an "indestructible" mass. You refuse to come to terms with the fact that the collapsing floors impact ONE floor at a time, not EVERY floor all at once. By now, we can conclude that your obtuseness is willful, a clumsy attempt to obfuscate and deceive.
sylvan8798
Master Poster
- Joined
- May 25, 2009
- Messages
- 2,847
Would you say, along these same lines, that if a small chunk C of a building falls by gravity on a different building K, where K is certainly designed to carry more than the small part C, that it could not cause a section of building K to collapse basically to the ground?
C, being dropped on or impacting K sideways, will only cause local failures of K at the impact area or simply bounce off. I doubt very much that a local failure up top will produce a crush down of a section of K below to ground.
But if the C impact is sideways, some section of K above impact may displace down a little bit before arrest occurs.
In principle, you cannot one-way crush down a structure from above by dropping a smaller, weaker piece of structure on it
aggle-rithm
Ardent Formulist
I think this is all about semantics.
Sure, you could argue that part C could not destroy part A without itself being destroyed. From this perspective, I guess you could say that a "one-way crush down" is not possible. However, no one is claiming that such a thing has ever happened, so it's irrelevant.
aggle-rithm
Ardent Formulist
You are apparently using a definition of the phrase "in principle" of which I am unfamiliar.
Principle in this case is general law of cause and effect. So in general law of cause and effect a small upper structural part cannot one-way crush down a bigger, similar structure.
Nobody has been able to prove the opposite in practice or in theory. I have made an axiom out of it. Long time overdue, though.
Well, Bazant, Seffen, Mackey, NIST, BLGB and a few other dishonest characters suggest that a "one-way crush down" of a structure is not only possible but, therefore, occurs in reality. 911 seems to be their only example of the latter. Asking them to demonstrate the effect under controlled conditions is met by ... silcence.
aggle-rithm
Ardent Formulist
I would guess that they were using a simplified model to demonstrate some physical concept. To attempt a complete analysis of how the mobile portion comes apart would make the model needlessly complex, since this would have very little effect on the overall force.
Force is mass times acceleration. There is nothing in the formula about crushing.
But, why am I telling you this? You're a troll.
sylvan8798
Master Poster
- Joined
- May 25, 2009
- Messages
- 2,847
You doubt? or is this part of the Heiwa axiom?
Regardless of the height from which it is dropped?
Yes! Surprised? The height is just a question of energy applied by the small part C. How to convince you?
Start with a small height/energy and see what happens! There is a bounce!
Double the height/energy application! Some local failures followed by arrest.
Increase height/energy 10 times! Part C is really damaged but A still stands after arrest of C
Increase height/energy again 10 times. Part C is completely destroyed but parts of A are still standing. No one-way crush down of A has taken place so far. Parts of A are still connected.
Increase height/energy another 10 times. Same thing happens - you see when part C is completely destroyed it cannot damage A further. A completely damaged structure C cannot apply any energy on what remains of A.
Conclusion. A one-way crush down of A by C is not possible by dropping C on A.
Yes, I agree that A will be damaged ... but topic is Why a one-way Crush down is not possible. Don't change the subject.
Actually, when you apply a force on a mass, the mass accelerates in the direction of the force. So when a mass (WTC 1 upper part) drops on and contacts anything static (WTC 1 lower part), anything static applies a force on the mass and accelerates it. And maybe crushes it.
So lower part crushes or bounces off upper part. Is that what you say? If yes, I agree. Happens in a game of basket ball all the time.
Keep babbling. The thirteen falling floors do not hit ninety-seven floors all at once. They hit a single floor, the one immediately below, and then the process is repeated until the building is gone.
Yes, the real engineers at the ASCE journal would certainly be surprised that an engineering school gave a degree to someone who dreams that increasing the height from which C is dropped onto A makes no difference. As a combination of cocksure arrogance and hopeless obtuseness, you can't be topped.
- Status