Japan Skyscrapers Sway With 8.9 Earthquake but the WTC collapsed !! still beleive the 9/11 version?

reply to post by psikeyhackr


Ever see this model? Purdue did another for the Pentagon.

www.youtube.com...

As far as the WTC, go to 1:20....1:38...1:48...

www.youtube.com...

Looks like bending and breaking to me...c'mon now...Also looks like good floor models too...including trusses..inner columns...outer columns...

Originally posted by esdad71
reply to post by psikeyhackr

 

Ever see this model? Purdue did another for the Pentagon.

www.youtube.com...

As far as the WTC, go to 1:20....1:38...1:48...

ROFLMAO

That model is even more OBVIOUSLY STUPID than the north tower one.

Notice how it has the airliner's wings being sliced up by columns INSIDE the Pentagon. So how did the wings get inside without making elongated holes in the OUTSIDE of the building.

Are the people at Purdue trying to advertise their stupidity or do they just assume that the people watching their simulations are even more STUPID than they are.

ROFL

That is REALLY DUMB!!!

psik

reply to post by Varemia

The initial collapse fell straight down in one tower

The horizontal supports in a collapse model are entirely necessary to be at least somewhat present because the collapse was not a box lands on box scenario.

Psikey's model clearly interprets perhaps just the core columns impacting only themselves in a block-hits-block system, implying that 1: they fell straight down onto the other supports

I don't imagine that the collapsing floors would entirely arrest, but it would certainly provide a great deal of protection to the core, and perhaps stop the collapse from initiating in the first place.

So you are claiming that column vs column impacts would provide large resistance to collapse, but columns vs stacked up concrete floors and trusses are pretty much providing the equivalent resistance to collapse as fresh air? Interesting.

The thing is that the floors were not designed to withstand dynamic impacts.

I know they don't. That doesn't mean they can be accelerated without costing kinetic energy. You are completely side-stepping the points I made about energy. I was looking for an explanation as to how ~2/3rds free fall was maintained, meaning very little kinetic energy was lost in accelerating accumulated mass, failing columns and crushing concrete.

It would be akin to dropping a bowling ball on a glued together line of popsicle sticks (don't quote the simile for factual weights). It won't be slowed down very much.

A line of popsicle sticks that are capable of supporting approximately two bowling balls at rest would greatly decelerate a bowling ball dropped on them. The bowling ball would certainly not accelerate through the sticks at ~2/3rds free fall.

As it goes, once the horizontal supports fail simply from the initial impact, then the lateral debris will twist and bend the vertical supports

Debris does not twist columns and it's highly doubtful it would bend them to any significant degree.

The dynamics of that collapse would have severely damaged the integrity of the core's vertical supports right away and allowed for a much more thorough destruction.

It would not have damaged anything outside of the initiation zone.

The thing is, because there was less initial horizontal force on the core columns, they mostly just sheared away during collapse

Horizontal force is what causes shear in columns.

reply to post by Azp420


When your debris is steel and concrete, you get more force than paper and air. That's all I have to say. I'm no engineer, and I'm not going to go do a ton of intricate research and learn all the proper terms just so that you can be satisfied with a perfect post. Perhaps you don't understand the simplistic concept of heavy versus standing, but deceleration would not be to a significant degree. You act as if the kinetic energy would be reduced by 50% or more, like the collapse should have almost stopped at each collapsing level. That would be the first time in a history a collapse has ever looked like that in my experience. It either stops at one point or it goes all the way down to the ground.

reply to post by Varemia

Again you have completely side-stepped me as to how ~2/3rds free fall was maintained, meaning very little kinetic energy was lost in accelerating accumulated mass, failing columns and crushing concrete. WTC7 also had a period of complete free fall.

When your debris is steel and concrete, you get more force than paper and air. That's all I have to say. I'm no engineer, and I'm not going to go do a ton of intricate research and learn all the proper terms just so that you can be satisfied with a perfect post.

I'm not nit-picking over incorrect use of terms (although I could have had a field day, I had a very hard time trying to decipher your posts). It's entire concepts that you are presenting which I'm pointing out to be wrong.

Perhaps you don't understand the simplistic concept of heavy versus standing, but deceleration would not be to a significant degree.

No idea what you're referring to here, but I can assure you they don't just hand out engineering degrees to anyone that asks for one. Some understanding of basic physics is required.

You act as if the kinetic energy would be reduced by 50% or more, like the collapse should have almost stopped at each collapsing level.

I never made any such claim or suggestion. There should certainly have been a decrease in velocity at each level though.

That would be the first time in a history a collapse has ever looked like that in my experience.

And as we know, you're no engineer and your experience is almost nil, so don't take so much offense and keep an open mind. What I describe is how every single collapse in history has ever looked (deceleration of the falling mass once it meets undamaged structure). Never in history has a properly designed structure accelerated through itself at near free fall (~2/3rds).

It either stops at one point or it goes all the way down to the ground.

As opposed to some sort of third option?

reply to post by Azp420


Actually, there's a difference between proving wrong and asking for something to be proven right. You haven't proven that the tower should have slowed down considerably during its collapse. You have just asked me to prove that it shouldn't have. I don't know how to do that, since I am not an engineer. I was just describing what made sense to me in the best way I could.

reply to post by Varemia

Actually, there's a difference between proving wrong and asking for something to be proven right. You haven't proven that the tower should have slowed down considerably during its collapse. You have just asked me to prove that it shouldn't have.

All I did was point out the errors in your claims and ask you to back them up.

I don't know how to do that, since I am not an engineer. I was just describing what made sense to me in the best way I could.

If your claims are pure speculation then don't expect people to take them seriously.

You haven't proven that the tower should have slowed down considerably during its collapse.

As the top section was accelerating at ~2/3rds free fall the undamaged structure was only applying an average upwards force on the top section of about 1/3rd of the upwards force it applied before collapse (which was likely about half of its capacity). I find it extremely unlikely (for whatever my opinion is worth) that the undamaged structure could be destroyed by an average force of only about 1/6th of its capacity in its original loading configuration. I guess this is why the NIST report stops short of attempting to explain this.

WTC7 has even more ridiculous accelerations from less damage and is what really gives the game away.

reply to post by Azp420


That's exactly what I'm trying to say. Your claims are just as unsubstantiated as mine. In the end we're just giving our unscientific opinions, especially since 9/11 is the only time the culmination of circumstances has ever come together as it did. First, there was a world first in a jetliner impacting a skyscraper of a unique (and renowned for) design. Then, it happened a second time. Then, for the first time, skyscrapers collapsed from the top down (and after internal collapse in WTC7). It was a unique day, and neither you nor my experience can amount to anything unless we do a lot of serious modeling and testing akin to something mythbusters would do (but with less theatrics and more actual thought put into the experiments.

reply to post by Varemia

That's exactly what I'm trying to say. Your claims are just as unsubstantiated as mine. In the end we're just giving our unscientific opinions

I should have pointed out that I am a structural engineer, so my opinion is based on my education and experience. I don't expect you to take my word for that, when posting in the 9/11 forum I usually try to let the numbers and concepts in my posts do the talking. I believe the facts I presented in the last part of my previous post are a smoking gun.

Originally posted by Azp420
I believe the facts I presented in the last part of my previous post are a smoking gun.

Honestly, it doesn't matter if you built flying hotels. Even for engineers, something like 9/11 never happened before.

Here's an analysis of your previous post:

As the top section was accelerating at ~2/3rds free fall the undamaged structure was only applying an average upwards force on the top section of about 1/3rd of the upwards force it applied before collapse (which was likely about half of its capacity).

Where do these numbers come from? How do you know that the force coming down on the lower section was so small? Have you considered that it did not fall in a perfectly symmetric pattern? It would seem to me that uneven loading of extra weight on especially the horizontal structures would cause rapid failures.

I find it extremely unlikely (for whatever my opinion is worth) that the undamaged structure could be destroyed by an average force of only about 1/6th of its capacity in its original loading configuration. I guess this is why the NIST report stops short of attempting to explain this.

Again, trying to figure out how you calculated the force that the dynamic collapse was exerting.

WTC7 has even more ridiculous accelerations from less damage and is what really gives the game away.

If you have seen NIST's (correct) simulation, you'll see that it is indeed possible and makes sense based on the damage. I say correct because there are 2 simulations floating around. One which conspiracists tote as being ridiculous because it did not collapse the same way as WTC 7, and one which conspiracists ignore completely because it accurately depicts what happened to WTC 7. See, NIST did a simulation with the recorded damage and without the recorded damage. There was an approximately twenty foot high chunk blown out of the base, a good amount of corner damage, and if you look at pictures, you can see that even a chunk of the edge of the roof was damaged, so the "no debris could have hit the building" theory is out the window. Also, if you look at images of the buildings next to WTC 7, they were damaged by debris as well.

I think that the fact that people knew WTC 7 was going to collapse for hours before it did is a telling sign that it was obvious that the damage was enough.

Originally posted by Varemia
Where do these numbers come from? How do you know that the force coming down on the lower section was so small? Have you considered that it did not fall in a perfectly symmetric pattern? It would seem to me that uneven loading of extra weight on especially the horizontal structures would cause rapid failures.

What kind of DELUSIONAL PHYSICS is that?

Uneven loading should cause uneven damage which should lead to even more uneven loading.

That is the weird thing about the tilted top of the south tower not falling down the side.

It should have damaged one side of the building much more than the other resulting in increased tilt until the top portion fell down the side. And then the NIST does not mention the center of mass of that tilted portion. This is Grossly Incompetent Physics.

psik

The WTC collapsed verticaly

only that should be enought to discredit the official story
both plane hit in different place .. i would understand if only a few part would fall

or at one point after hours of burning at a thousand degree
certain beam would be affected .. making the top fall down in an angle
similar to that


This is a hollywood movie .. special effect was used
but more plausible script .. then the WTC official version lol
we know missiles can contain many warheads
fuel from a plane .. less likely to cause a vertical fall down even more effective then any missiles strike

The WTF vertical fall down is logicaly impossible to achieve without any explosives.. PERIOD

even more impossible .. a same result TWICE and the time they took to fall down
this is not a toothpicks tower

normaly an attack from a foreign entity hurt the entire country that was hit
government included

people made billions because of last minute decision
like they all knew what was going to happen to the WTC





History will prove one day without any doubts .. that the WTC is the Reichstag of America

Originally posted by psikeyhackr

Originally posted by Varemia
Where do these numbers come from? How do you know that the force coming down on the lower section was so small? Have you considered that it did not fall in a perfectly symmetric pattern? It would seem to me that uneven loading of extra weight on especially the horizontal structures would cause rapid failures.

What kind of DELUSIONAL PHYSICS is that?

Uneven loading should cause uneven damage which should lead to even more uneven loading.

That is the weird thing about the tilted top of the south tower not falling down the side.

It should have damaged one side of the building much more than the other resulting in increased tilt until the top portion fell down the side. And then the NIST does not mention the center of mass of that tilted portion. This is Grossly Incompetent Physics.

psik

You have no idea how hard it is to avoid breaking the terms and conditions when I see your crap show up again and again...

Delusional physics? It's delusional that an uneven weight load will cause failure faster than an evenly distributed load? Are you a moron? Have you ever put weight on a surface before? Surfaces hold weight better when it is evenly, KEY WORD, evenly distributed!

Also, in order for the top to topple over to the side, there would have to be enough resistance from both the collapsing section and the lower section to allow it to break away from the still intact supports. THE TOWERS WERE NOT MADE OF SOLID BLOCKS. How many times to I have to repeat that to get it through your skull? They will not behave under design behaviors when subjugated to forces that they were not designed for! I guarantee you that the designers of the tower did not have an angled thirty floor collapse in mind when they were considering stability. If they were factoring in extra load for accidents such as plane impacts, it was still only for if the building remained standing in one piece. The failure is what caused all the issues. Some people are just dumber than a box of rocks.

Originally posted by Varemia
It's delusional that an uneven weight load will cause failure faster than an evenly distributed load? Are you a moron? Have you ever put weight on a surface before? Surfaces hold weight better when it is evenly, KEY WORD, evenly distributed!

When it is put into context of a 110 story building it is completely delusional.

The top tilting is not going to cause the bottom to suddenly not be able to hold it's mass, as buildings are always built to hold a lot more than their own weight. It's called a factor of safety or safety factor, you should go learn about it.

The tilting top should have continued it's tilt, according to a well known law of physics known as 'angular momentum'. An object experiencing angular momentum will maintain that momentum unless acted on by an outside force. If you keep that in mind and watch the collapse, the only way the top could have changed it's angular momentum is if the pivot point completely disappeared, and there was no resistance to stop the top from dropping. If the top met any resistance, such as the next floor bellow the pivot, when it dropped the momentum would have cause it to continue tilting off the side, not straight down through the path of most resistance.

reply to post by psikeyhackr

Uneven loading should cause uneven damage which should lead to even more uneven loading.

This is Grossly Incompetent Physics.

Funny how the responses to your posts are so often found....in your posts.

Actually, the eccentric loading did cause eccentric damage, however, as eccentric as the collapse sequence may have been in the end the entire building was involved. You just don't have a very deep understanding of how physics is applied in the very real and very complex world.

reply to post by ANOK


I doubt that the designers would design the horizontal supports to withstand an accelerated, concentrated mass impacting the trusses. You keep acting like the vertical supports were the only things falling, and that they were able to land perfectly on each other so as to resist with their designed specifications. It doesn't matter if they designed the vertical load to be 100 times the building's weight. If the horizontal supports get taken out, it's so long sweet Suzy.

Originally posted by Varemia
reply to post by ANOK

 

I doubt that the designers would design the horizontal supports to withstand an accelerated, concentrated mass impacting the trusses.

You talk like the top was a solid block, but the bottom was just one floor and a few trusses. The top and bottom were the same, floors held by trusses, when the two floors impacted, the forces would be equal (Newtons 3rd law). The impacted floor would push up equally against the falling floor, or the whole bottom block would push up equally against the falling top block. This is why it is wrong to think of the top as a block and the bottom as just one floor. If you do then you are wrong and any model or calculation would be wrong.

Just like trying to compare someone dropping a weight on your head, it's wrong and not in context.

Regardless I don't know what makes you think a falling floor, lightweight concrete and thin steel plates (where did they go BTW?), is going to overcome the trusses and fasteners of the floor bellow. The fasteners have to be much stronger than floor itself, because it is more force on a smaller point, and has to hold all the load of the floor +.

And regardless again there is not enough mass left in the footprints to support your claim. This is why NIST does not support the progressive/pancake collapse you are claiming. You need to come up with a more reasonable explanation that doesn't ignore the laws of motion and momentum conservation.

You keep acting like the vertical supports were the only things falling, and that they were able to land perfectly on each other so as to resist with their designed specifications. It doesn't matter if they designed the vertical load to be 100 times the building's weight. If the horizontal supports get taken out, it's so long sweet Suzy.

Not at all. You are not considering the resistance of undamaged trusses that would not simply instantly break.
You are ignoring equal opposite reactions, which means the falling floors fasteners would have as much force on them as the impacted floors fasteners. There was very little mass left in the footprints, so the majority had to be ejected, that means floors were destroying floors as the collapse progressed. If floors were destroying floors, and taking in mind equal opposite reactions and momentum conservation, the top block could not have stayed whole until the bottom floors were all gone. That is the impossible physics. The top floors must have been destroyed along with the bottom ones IF it fell as you want to claim, from gravity and KE, because no floors were left. KE would be lost to friction/resistance as the fasteners were compromised. IF the floors could destroy each other from gravity and KE, the top section would run out of floors before the bottom did, simple maths. This is why in a classic progressive/pancake collapse there is always floors left in the footprint stacked up.

The only way it could happen is from another energy acting to take away the resistance, allowing more floors to fall then just a few on the top section.

NIST could not, or didn't want to, explain the actual collapses, so what makes you think you can?

Edit; BTW...

A collision is an interaction between two objects that have made contact (usually) with each other. As in any interaction, a collision results in a force being applied to the two colliding objects. Newton's laws of motion govern such collisions.

Just so you know Newtons laws of motion govern collisions. It's not just 'one part of the physics' as asdad claims. You will find your KE and gravity are also considered.

www.physicsclassroom.com...

reply to post by Varemia

Honestly, it doesn't matter if you built flying hotels. Even for engineers, something like 9/11 never happened before.

Physics has happened before. There was a time when even for engineers, a moon landing had never happened before. Yet they were able to put a man on the moon using physics equations, because physics had happened before then too.

Where do these numbers come from? How do you know that the force coming down on the lower section was so small?

2/3rds free fall is the generally accepted acceleration of the top sections. I can post evidence if you wish. The equal and opposite force applied to the lower section is the force which corresponds to such an acceleration. I can post some equations if you don't know how to work it out.

Have you considered that it did not fall in a perfectly symmetric pattern? It would seem to me that uneven loading of extra weight on especially the horizontal structures would cause rapid failures.

Yes, that is why I specified it was an average force. Remember though, that if the force is higher in certain members it must be lower in others to maintain the average. That is why concentrations of force would have little overall effect.

If you have seen NIST's (correct) simulation, you'll see that it is indeed possible and makes sense based on the damage. I say correct because there are 2 simulations floating around.

Pretty sure I've seen the right one. Have you got a link handy? A google search just turned up criticisms of what I suspect to be the wrong one.

I think that the fact that people knew WTC 7 was going to collapse for hours before it did is a telling sign that it was obvious that the damage was enough.

I think it is telling also, especially as the BBC reported it had collapsed before it actually did. It is telling because a steel structure had never totally collapsed from fire alone and there were no visible signs suggesting a collapse was on the cards.

Originally posted by hooper
reply to post by psikeyhackr

 

Uneven loading should cause uneven damage which should lead to even more uneven loading.

This is Grossly Incompetent Physics.

Funny how the responses to your posts are so often found....in your posts.

Actually, the eccentric loading did cause eccentric damage, however, as eccentric as the collapse sequence may have been in the end the entire building was involved. You just don't have a very deep understanding of how physics is applied in the very real and very complex world.

More Stupid Talk that you try to imply is meaningful.

Where was the center of mass of the top of the south tower.

NO DATA!!!

Incompetent Physics.

psik

reply to post by Azp420

I think it is telling also, especially as the BBC reported it had collapsed before it actually did. It is telling because a steel structure had never totally collapsed from fire alone and there were no visible signs suggesting a collapse was on the cards.

May I suggest looking into the NIST report on building 7? Specifically page 301 and a list of damage assestment including seeing a bulge in the southwest corner of the building among other things including a large gash in the side of the building. Plenty of visible signs the building was going to collapse.