Outside energy had to be introduced for the twin towers to collapse the way they did

Originally posted by waypastvne

Originally posted by psikeyhackr
You people can't tell us the strength of the connections of the trusses relative to the weight of the floors so until that information is correctly determined than trying to build a tube in tube model would be STUPID.

Another simpler way than building models, is to:

Check and see what component had the lowest cross section in the load path.

That would be the truss seat conections.

Next find out if the truss seats show signs of failure.

Yes they do.

Conclusion: Progressive collapse occurred due to failure of the truss seat connections.

And the load path IS WHAT YOU DEFINE IT TO BE.

The truss seats transferred the load from the floor to the columns. The load from the columns did not get put on the truss seats.

Any falling portion of the core of the north tower had to come down on the stationary core directly below.

psik

Originally posted by psikeyhackr

And the load path IS WHAT YOU DEFINE IT TO BE.

The load path on the open floors can go nowhere else except for through the truss seats.

The floors were the progressive part of the progressive failure. The cores were not.

Originally posted by waypastvne

Originally posted by psikeyhackr

And the load path IS WHAT YOU DEFINE IT TO BE.

The load path on the open floors can go nowhere else except for through the truss seats.

The floors were the progressive part of the progressive failure. The cores were not.

ROFLMAO

So what was the path of the load from the truss connections to the foundation of the building? Or are you saying the building did not rest on its foundation.

psik

Originally posted by psikeyhackr

I don't know or care what you mean by REPRESENTS. The paper loops perform the SAME FUNCTION as columns in the WTC. They are what holds up the mass of the washers against gravity. In order for that mass to move downward the paper loops must sustain damage. That requires energy.

It is not my fault that you think in terms of analogy instead of in terms of how physics works.

My paper loops cannot punch holes through the washers the way columns in the WTC would be able to punch holes through concrete floors. But punching those holes would require energy also. Thereby slowing the falling mass.

What is the matter, no pictures of the core which the NIST says supported 53% of the weight?

Are you saying something blew perimeter columns away from the building and that is why they are not like my model?

ROFLMAO

You don't seem to get the point of my model. My point is that the building could not have collapsed. It would arrest. Therefore the perimeter columns that are not like the crushed loops of my model just emphasize my point.
psik

edit on 7-11-2011 by psikeyhackr because: (no reason given)

How would columns punch up through floor THEN since the floors were suspended between the walls and core steel.

YOUR model is flawed because it dosen't allow for lateral movement which the columns in the towers could do!, YOU cant prove relative strengths are the same for your model are the same as real life can YOU.

The flaw with the towers was how the floorslabs were supported and the fact they could drop on the one below.

Originally posted by septic
reply to post by waypastvne

 

reply to post by waypastvne

 

If the truss seats failed, that implies the floors fell...wouldn't that mean the walls and core would be still standing?

Only if you think that when thousdands of tons of concrete floor slab and steel hit the floors below that NO force would be applied to the core or walls may be in your ideal world you thought that would happen!

Originally posted by psikeyhackr

Originally posted by waypastvne

Originally posted by psikeyhackr

And the load path IS WHAT YOU DEFINE IT TO BE.

The load path on the open floors can go nowhere else except for through the truss seats.

The floors were the progressive part of the progressive failure. The cores were not.

ROFLMAO

So what was the path of the load from the truss connections to the foundation of the building? Or are you saying the building did not rest on its foundation.

psik

The floor connections were welded to the columns as they only suported the floor they were on the connections were the same size all the way down they were designed only to take the load on the floorslab x the FOS, the other thing is that the columns dont all have the same number of truss connections.

Look at this image



The column tree on the top left has 2 angle seats and 2 damper plates below them, now look at the other colums next to the decking ONLY the centre has an angle seat and damper plate.

I suggest you look up some actual construction problems before you make any comments psik I will mention this again for the hard of LEARNING.

In practice, buckling is characterized by a sudden failure of a structural member subjected to high compressive stress, where the actual compressive stress at the point of failure is less than the ultimate compressive stresses that the material is capable of withstanding

ALL THE IMPORTANT BITS UNDERLINED so you dont have to think or learn!

Originally posted by wmd_2008
The floor connections were welded to the columns as they only suported the floor they were on the connections were the same size all the way down they were designed only to take the load on the floorslab x the FOS, the other thing is that the columns dont all have the same number of truss connections.

Look at this image

I have seen that picture so many times it is ridiculous.

When do we ever see pictures of core columns with horizontal beams attached at that same stage of construction of the towers?

psik

reply to post by psikeyhackr


i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...

I found a bunch of these here:

letsrollforums.com...

That's pretty much the best I could find of the core columns. I got a lot from the beginning of construction and a few at a distance during construction of the upper portions.

I like this one:


Can't tell exactly what level this is on, but it's interesting:

reply to post by Varemia


i do like the second large photo of the core. You can actually see the tabs where the truss seat is going to be attached to the floor truss top. This gives a great view of just how the floors were attached to the core and exterior columns.

Originally posted by Varemia
reply to post by psikeyhackr

 

i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...
i.imgur.com...

I found a bunch of these here:

letsrollforums.com...

That's pretty much the best I could find of the core columns. I got a lot from the beginning of construction and a few at a distance during construction of the upper portions.

Apparently you can't notice the difference in the range from which those pictures were taken compared to the one of the trusses that we see all of the time. I does kind of look like what is being portrayed as a weak point is displayed so much better than the joints in the core. I guess people are not supposed to know much about those.

psik

Originally posted by psikeyhackr

Apparently you can't notice the difference in the range from which those pictures were taken compared to the one of the trusses that we see all of the time. I does kind of look like what is being portrayed as a weak point is displayed so much better than the joints in the core. I guess people are not supposed to know much about those.

psik

edit on 9-11-2011 by psikeyhackr because: (no reason given)

Ok. Now it sounds like you're just making excuses. You wanted pictures of the core. I found them. Now use your superior brain power and work it out.

Originally posted by Varemia

Originally posted by psikeyhackr

Apparently you can't notice the difference in the range from which those pictures were taken compared to the one of the trusses that we see all of the time. I does kind of look like what is being portrayed as a weak point is displayed so much better than the joints in the core. I guess people are not supposed to know much about those.

psik

edit on 9-11-2011 by psikeyhackr because: (no reason given)

Ok. Now it sounds like you're just making excuses. You wanted pictures of the core. I found them. Now use your superior brain power and work it out.

Oh sure, you can see the joints in the picture of the trusses and you can't see the joints in the pictures you supplied. I guess everyone needs to not think about those joints in the core.

psik

Originally posted by psikeyhackr

Originally posted by Varemia

Originally posted by psikeyhackr

Apparently you can't notice the difference in the range from which those pictures were taken compared to the one of the trusses that we see all of the time. I does kind of look like what is being portrayed as a weak point is displayed so much better than the joints in the core. I guess people are not supposed to know much about those.

psik

edit on 9-11-2011 by psikeyhackr because: (no reason given)

Ok. Now it sounds like you're just making excuses. You wanted pictures of the core. I found them. Now use your superior brain power and work it out.

Oh sure, you can see the joints in the picture of the trusses and you can't see the joints in the pictures you supplied. I guess everyone needs to not think about those joints in the core.

psik

Do you really think that the construction workers were concerned with taking pictures of everything up close just for you? You have enough information to see the structure and basic connections of the core. Yet you still continue to act as if you have no idea how it was made. The vertical columns were welded together, and the trusses were bolted on. What is unclear here?

Here, I found another picture which shows it closer up:



From here.

Originally posted by Varemia
Here, I found another picture which shows it closer up:

From here.

That portion with the diagonals was the support for the kangaroo cranes. They were not part of the core. I presume they were removed after construction.

I think you are doing a great job of demonstrating that close ups of horizontal to vertical joints in the core cannot be found and yet that same old same old picture of floor pans on trusses connecting to perimeter columns is supposed to convince everybody that collapse was possible.



psik

Just one more thing. I found a site with a 20 minute video describing every aspect of construction, with scenes such as this that show core construction:



And I found one more picture of the construction:



Oh, here's the video:

www.pbs.org...

Originally posted by psikeyhackr

Originally posted by Varemia
Here, I found another picture which shows it closer up:

From here.

That portion with the diagonals was the support for the kangaroo cranes. They were not part of the core. I presume they were removed after construction.

I think you are doing a great job of demonstrating that close ups of horizontal to vertical joints in the core cannot be found and yet that same old same old picture of floor pans on trusses connecting to perimeter columns is supposed to convince everybody that collapse was possible.

psik

You really are being an ass to me. I know that's the crane. the picture shows more than that, smart one.

reply to post by Varemia


Great job on digging up those photos and links to the pbs documentary.

Originally posted by DrEugeneFixer
reply to post by Varemia

 

Great job on digging up those photos and links to the pbs documentary.

I really wasn't expecting to find as much as I did. Hopefully they are useful to people that are interested in the actual construction of the towers. The box welds appear to be the strongest part of the core, and it seems fairly obvious that the horizontal connections were basically bolted on within the core (though, correct me if I'm mistaken).

Originally posted by Varemia

Originally posted by psikeyhackr

Originally posted by Varemia
Here, I found another picture which shows it closer up:

From here.

That portion with the diagonals was the support for the kangaroo cranes. They were not part of the core. I presume they were removed after construction.

I think you are doing a great job of demonstrating that close ups of horizontal to vertical joints in the core cannot be found and yet that same old same old picture of floor pans on trusses connecting to perimeter columns is supposed to convince everybody that collapse was possible.

psik

You really are being an ass to me. I know that's the crane. the picture shows more than that, smart one.

Were any of those photos well lighted and close up like that one we see of the truss and perimeter panels that we see ALL OF THE DAMN TIME?

NO!

psik