Question for the twoofers about why NIST is wrong

[Wizard]

I'll re-phrase it for you: Will a structure collapse if subjected to a load it can not bear. Yes or no?

Depends on the structure, the nature of the load and many other things.

I want to see a report on the total collapse that has similar detail to the initiation

 

[WildCat]

Depends on the structure, the nature of the load and many other things.

So you are claiming that a structure exists that will not collapse when subjected to a load it can't bear?

What an illuminating window into your thought process!

 

[stateofgrace]

Depends on the structure, the nature of the load and many other things.

I want to see a report on the total collapse that has similar detail to the initiation

Do you believe the NIST final report into the initiation of the collapses?

 

[Wizard]

So you are claiming that a structure exists that will not collapse when subjected to a load it can't bear?

What an illuminating window into your thought process!

So you are suggesting that any structure that exceeds its load bearing capacity will totally disintegrate? Do you have any examples of this other than the wtc?

In the spirit of the opening post please explain in the following fashion:

"The total collapse of the buildings was inevitable because....(insert science/math arguments here)"

 

[WildCat]

So you are suggesting that any structure that exceeds its load bearing capacity will totally disintegrate?

No, I said it will collapse. Perhaps you should read more slowly and comprehend the words next time.

Do you have any examples of this other than the wtc?

The wtc did not "totally disintegrate", so the prmise to your question is false.

In the spirit of the opening post please explain in the following fashion:

The total collapse of the buildings was inevitable because the structure was subjected to a load it could not bear.

 

[Wizard]

No, I said it will collapse. Perhaps you should read more slowly and comprehend the words next time.


The wtc did not "totally disintegrate", so the prmise to your question is false.


The total collapse of the buildings was inevitable because the structure was subjected to a load it could not bear.[/quote]

Yeah I didn't think you could.

When will you be submitting that sentence to an engineering magazine for peer review? PMPL

 

[WildCat]

Yeah I didn't think you could.

But I did!

When will you be submitting that sentence to an engineering magazine for peer review? PMPL

You think a paper stating that a structure will collapse if it is subjected to a load it can't bear will get published in an engineering journal?

Sorry to laugh so, but that has been a given ever since a cave man long ago sat on the flimsy lean-to he had constructed.

 

[gumboot]

Depends on the structure, the nature of the load and many other things.

Wow. Just wow.

-Gumboot

 

[Wizard]

But I did!


You think a paper stating that a structure will collapse if it is subjected to a load it can't bear will get published in an engineering journal?

Sorry to laugh so, but that has been a given ever since a cave man long ago sat on the flimsy lean-to he had constructed.

If the total collapse is so obvious then you won't have any trouble providing me with the actual calculations

 

[kookbreaker]

If the total collapse is so obvious then you won't have any trouble providing me with the actual calculations

Load > Load Bearing Capacity = Collapse.

 

[WildCat]

If the total collapse is so obvious then you won't have any trouble providing me with the actual calculations

I fail to see the point in discussing this with someone who believes that some structures won't collapse when subjected to a load they can't bear.

 

[WildCat]

Load > Load Bearing Capacity = Collapse.

That's even simpler than what I came up with, but I bet Wizard still can't comprehend it.

 

[rwguinn]

Depends on the structure, the nature of the load and many other things.

I want to see a report on the total collapse that has similar detail to the initiation

If you will spend the several billion $ it will require to develop and construct the computer that can handle the calculations (it doesn't exist yet), and the several billion $ to develop software to do the calculations (same existence problem), and the additional several 10's of billion $ to the testing so that the analysis can be correlated to reality (as all good models are), and are willing to wait the several months after that to get the results of the calculation (the iterative process will be very, very slow--billions of calculations per second will be required), we can get you the position of most of the large pieces after collapse. Not all of them, but most.
Or, you can realize that under the forces the tower systems were subjected to, and the energies released upon the initial yielding of the materials involved, termination of the collapse would be complete only when the height of the rubble pile prevented further collapse.

 

[Wizard]

I fail to see the point in discussing this with someone who believes that some structures won't collapse when subjected to a load they can't bear.

Yep didn't think you could. You haven't got a clue why the whole structure was destroyed have you?

I think my work is done in this thread.

Thanks for the laughs. The best one was the report that was linked to a by a person claiming it was a substitute for interviewing engineers but was in fact about gathering evidence. He had not even bothered to read it lol

Priceless

 

[kookbreaker]

Yep didn't think you could. You haven't got a clue why the whole structure was destroyed have you?

I think it was made clear: Load > Load Bearing Capacity = Collapse.

That you cannot grasp this basic concept of structures is not our problem

I think my work is done in this thread.

If your work was making yourself look like an idiot, you were done a while ago. But we appreciate the overtime effort to make sure you did the job right.

 

[WildCat]

Yep didn't think you could. You haven't got a clue why the whole structure was destroyed have you?

I think my work is done in this thread.

Thanks for the laughs. The best one was the report that was linked to a by a person claiming it was a substitute for interviewing engineers but was in fact about gathering evidence. He had not even bothered to read it lol

Priceless

 

[gumboot]

Sometimes with these troofers, I get this image of Mork from Mork and Mindy going "na noo na noo na noo" followed by this icon:



-Gumboot

 

[rwguinn]

Yep didn't think you could. You haven't got a clue why the whole structure was destroyed have you?

I think my work is done in this thread.

Thanks for the laughs. The best one was the report that was linked to a by a person claiming it was a substitute for interviewing engineers but was in fact about gathering evidence. He had not even bothered to read it lol

Priceless

I am sorry, I will likely get suspended here--
But you are as stupid as they come. I have never seen or heard anyone that can come close to the idiocy you have shown here.
for any collumn, F=M*A=K*X, so
X=(M/K)*A
K is stiffness, M is mass, x is deflection. Under 1 g (A), we can measure the deflection, because we know how long the collumns were without gravity making them shorter. If M gets bigger, or K gets smaller, X grows. as parts bend, buckle, and/or sever, K gets smaller, and X grows.
Still have a problem? Don't bother taking a class, then, because you are too stupid to learn anything.

 

[The Almond]

Yep didn't think you could. You haven't got a clue why the whole structure was destroyed have you?

I think my work is done in this thread.

Going so soon? What about all those really great questions I asked you?

Thanks for the laughs. The best one was the report that was linked to a by a person claiming it was a substitute for interviewing engineers but was in fact about gathering evidence. He had not even bothered to read it lol

Priceless

Let's perform a thought experiment, shall we? Have you ever played the game Jenga? A group of people construct a wooden tower using alternating patterns of 3 wooden blocks, and then they take turns removing pieces. The winner is the last person to successfully remove a piece.

Jenga is an interesting sidebar into a branch of newtonian mechanics known as statics. The tower has some interesting properties. First, each floor (except for the top floor) must be in static equillibrium in order to prevent the tower from collapsing, second, there are two possible equillibria states. One involves equillibrium with two blocks and one with only one block.

The Jenga tower is a good model for progressive collapse because it follows the two conditions that real towers must posess. Each floor must be in static equillibrium and each floor has two states of equillibrium: the determinate and the indeterminate. Consider that the single beam Jenga floor is the determinate case wherein the entire weight of the structure above rests on one beam. In the determinate case, the stress on the beam is equal to the weight of the structure above the beam.

Consider the indeterminate case of two beams. Despite the fact that each beam now carries half of the load of the above structure, the removal of either of the beams will cause the structure to collapse. Thus, despite the very true assertion that the tower is redundantly supported (indeed, only one beam is necessary, as proved by the determinate case), that has no bearing in its collapse. As soon as one beam is removed, collapse becomes inevitable. Notice that we do not make the assumption that the lower levels of the Jenga tower will support the load. Indeed, the Jenga beams are capable of supporting extremely heavy loads, but they are not capable of stopping the collapse.

This is a very important point: the load bearing capacity of the floors below is not a measure of their ability to stop collapse. Indeed, stopping a collapse would require a damping ability; the ability to slow down and dissipate all of the potential energy.

Like the wooden blocks of the Jenga tower, the WTC towers had rigid supports. Had they the structural capacity to bear the weight of one extra floor, the fact remains that Newton's 3rd law must be obeyed. All of the energy that the upper portions of the WTC tower had as kenetic energy during their decent was reflected back to them by the portion of the tower that remained fixed to the ground. This force simply exceeds the material strength of the towers.

Consider that, for the multiple redundancies in the Jenga tower, only one beam needs to be removed in order to make collapse inevitable. The bowing of columns in the WTC tower was indeed the final block necessary to make the tower collapse. It is possible to examine and pinpoint the sequence of events that lead to the collapse initiation state in the same way that it is possible to determine the winner of a game of Jenga.

To summarize:
NIST made the assumption that collapse became inevitable at some point based on the very valid premise that the towers were rigid structures with no ability to absorb and dissipate the energy present in the falling sections of the towers. The WTC towers were incapable of stopping any form of collapse after it started.

Furthermore, the purpose of the NIST investigation was not to determine who was at fault for the WTC collapse. Rather, the genesis of the investigation was to determine what, if any, building codes needed to be changed in order to prevent another WTC type collapse. Indeed, it is far wiser to determine methods that prevent the lead up to a precise point in collapse initiation than to attempt to make any skyscraper capable of stopping progressive collapse. In the case of collapse initiation, NIST has outlined a very specific series of events leading to collapse, and it follows that an interruption of any of the events would prevent collapse.

 

[The Almond]

Man, I'm long-winded tonight.