How did you test the paper loops "TO DESTRUCTION"? Did you keep adding washers on top of the paper loop until it failed?
Exactly! And the washers were added gently. It took from 12 to 15 washers to collapse a single loop. I tested multiple loops to destruction. That is why there are 11 single loops at the top. My first extended static test had 3 triple loops, 19 double loops and 11 single loops. After standing over night the bottom 2 double loops had collapsed. I then switched to 5 triple loops and 17 double loops and left them standing for 3 days. That was the STATIC test. Then I raised the top 4 washers and dropped them. The results are in the video. That was the DYNAMIC test. Of course only YOU know what Static and Dynamic mean. psik
You mean the Twin Towers were not designed to withstand gravity? And no, the top 13% of the north tower was not raised an additional height of the building and then dropped. psik
Bottom line here, NOBODY has as yet been able to model the building performance in the manner of the collapse of the WTC towers! I note that all an engineer needed to prove that the gasket on the space shuttle rockets was unsafe at lower temperatures, was a glass of ice water and a sample of the gasket material. so much for ROCKET SCIENCE .... this is a matter of proving the absolutely ludicrous allegation from the NIST that total collapse was inevitable after collapse initiation. and in fact I challenge that allegation and personally I ( as a taxpayer here ) am VERY unhappy with having my tax dollars spent on publishing such obvious rubbish!
I can see the poster who claims to have almost gone to MIT still hasn't read the free open source MIT coursework I directed him to. The paper loops in some people's models fail in crush mode. The tower columns failed due to buckling. The test is to design a model that causes the support structure to buckle, not crush. Square cube law, and ignorance of structural mechanics certainly do limit the possibility that some folks would ever accomplish that task. Exit question: How many slender columns are contained in the model being discussed?
Oh look, a structure comprised of slender columns, with more mass at the bottom than at the top, that collapses due to an instability at the top, that propigates a wave of instability through the entire structure. https://www.youtube.com/watch?v=GPjddqhB7f8 I guess it can be done.
Hey psikeyhackr. Your model is in no way relevant to the physics of the tower collapse. Want to know what your biggest mistake is? Take a look at this screen shot from your video. The fact that you couldn't figure this out for yourself is pathetic to say the least. Your model has each washer incorporated into the support structure so that each washer, the further down you go, supports the weight of all the washers and paper loops above.
I disagree. The biggest mistake is the big cantilever in the middle that restrains the entire column. In effect he created a structure that limits buckling, and then crows when the structure fails to buckle. Take out the wooden dowel and let's see how the tower performs.
If he was trying to model the collapse initiation, I would agree. He is trying to show that what remained of the lower section after the collapse initiation should have brought the descending upper section to a halt. He uses the simplest of models to try and show this, but fails miserably. Buckling may have been the dominant failure mode for the collapse initiation, but once the upper section started to descend, the main failure mode for the rest of the structure was the overloading/destruction of the floors AND the shearing of the floor truss supports attached to the perimeter and core columns as the upper mass descended. The support mechanism (the paper loop) for each floor in his model is "connected" from beneath the washer and then "connected" to the top of the next washer below. In order to correctly model the collapse, he would need to create a support mechanism for each washer that supports each individual washer from below. That support mechanism for each washer can only then be connected to a central support structure (the dowel), and should not incorporate the lower floors in any way.
The title of your video is "Gravitational Collapse onto Cumulative Supports". The floor supports were not "cumulative" as has been explained. The floor trusses supported ONLY the floor they were attached to and transferred the load to the core and perimeter columns. Your paper loop supports do not reflect reality.
It's not just the dominant mode for collapse initiation, it was dominant mode of column failure through the entire collapse. The long slender columns in the structure of the WTC didn't crush. They buckled. What the creator of the model fails to realize is the difference between crush and buckling modes of failure. For the vast majority of materials, much less energy is required to buckle a long slender column than it takes to crush a short column of the same material. This is the very reason his model requires an auxiliary support system (the dowel) Without the dowel, the "tower" would buckle under it's own static load. He's said so himself. I get what you're trying to get at, but you have to get him to realize the load bearing importance of the dowel before you instruct him to connect his structure to it. I guarantee you that he doesn't think the dowel affects his "gravitational" collapse. And that's really the biggest problem with his premise.
Bottom line here, with this whole discussion the point is that the tower(s) collapsed straight down and were completely destroyed, how is it that anybody should say "total collapse was inevitable ...... " ( that is for any circumstance other than controlled demolition? ) ????????
Where's your 3D lattice showing the weakened/severed core columns caused by the impact? How do your load "flow" arrows bypass those weakened/severed components? Where is your 3D lattice model showing the further weakening of components AFTER the impact due to the fires and how that further affects the load "flow"? In your 3D lattice model, how much of an increased load can each fully functional connection node take due to the failings of other connection nodes before they fail? You see Koko, it takes much more than a 2D representation of a damaged perimeter wall to figure out how the towers collapsed.
Not to mention that the curtain-wall lattice's primary purpose was not to transmit load to ground. It's purpose was to transmit wind load through the floor truss system to the core.
you dont seem to grasp how a lattice works, look back a couple posts, the arrows arent drawn 'perfectly' exacting to the expected forces, however you can easily get a good picture what happens when you severe a column how the load is redistributed. What you said is wrong btw. Well 1/2 wrong
Where's your 3D lattice showing the weakened/severed core columns caused by the impact? Wheres yours? How do your load "flow" arrows bypass those weakened/severed components? In a word? Angular forces for one. You may want to consider getting a degree to fully understand it since complex 3d calculations are required. Where is your 3D lattice model showing the further weakening of components AFTER the impact due to the fires and how that further affects the load "flow"? Which fire are you talking about? I see little to no fire worth mentioning. Otherwise the lattice only extends the forces operate the same way. In your 3D lattice model, how much of an increased load can each fully functional connection node take due to the failings of other connection nodes before they fail? The 3d lattice below is a conceptual model to demonstrate how wrong most of these debunkers huggers and posers are in what they would have people believe is bonafide analysis. You see Koko, it takes much more than a 2D representation of a damaged perimeter wall to figure out how the towers collapsed. That is why I gave you a 3d pictorial complete with arrows that while not 'precisely' drawn give engineers a great working example how efficiently lattice construction works and how incredibly strong the wtc was.
Something has to be cumulative in every skyscraper. That is why I distinguish LEVELS and FLOORS. It is so interesting that people claiming to know so much about REALITY don't just build a physical model and give us a demonstration. My model is not a Tube-in-Tube design. A decent one would be much more difficult and expensive to construct than what I made. But anyone can duplicate mine for less than $50. I don't see how to make a good repeatable tube-in-tube design that can be repeatedly tested to destruction without using a 3D printer. I guess our engineering schools that charge more than $100,000 for 4 years of education can't afford to do a decent model. Everyone is expected to take their word. But in actuality most schools have not discussed the subject officially. They don't even discuss the center of mass of the tilted top portion of the south tower. Very Scientific! psik
