Electron microscope analysis of steel spheres from WTC site

[Justin A]

"[16:20] Nielsio: These buildings were designed to take airplane hits"

This was my favorite part of the chat log.

[Nielsio]

[ QUOTE ]
"[16:20] Nielsio: These buildings were designed to take airplane hits"

This was my favorite part of the chat log.

[/ QUOTE ]

Frank A DeMartini, manager of WTC construction and project management on airplane impacts and structural integrity
http://www.youtube.com/watch?v=HGhWkRAR1Vc
(44s clip)

[Neuge]

[ QUOTE ]
[ QUOTE ]
"[16:20] Nielsio: These buildings were designed to take airplane hits"

This was my favorite part of the chat log.

[/ QUOTE ]

Frank A DeMartini, manager of WTC construction and project management on airplane impacts and structural integrity
http://www.youtube.com/watch?v=HGhWkRAR1Vc
(44s clip)

[/ QUOTE ]
Well that settles it.

Do you really think the construction manager of a building project has the ultimate say in a plane collision situation? Is he really qualified to comment on the structural mechanics of the fundamental building design?

The thing that kills me about 9/11 conspiracy nuts is that they claim random physics professors know more about the situation than anyone. While they usually are brilliant, they are not structural engineers who deal with the requisite continuum solid mechanics regularly.

Have you read the report by the world's leading demolition company yet?

[Nielsio]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
"[16:20] Nielsio: These buildings were designed to take airplane hits"

This was my favorite part of the chat log.

[/ QUOTE ]

Frank A DeMartini, manager of WTC construction and project management on airplane impacts and structural integrity
http://www.youtube.com/watch?v=HGhWkRAR1Vc
(44s clip)

[/ QUOTE ]
Well that settles it.

Do you really think the construction manager of a building project has the ultimate say in a plane collision situation? Is he really qualified to comment on the structural mechanics of the fundamental building design?

The thing that kills me about 9/11 conspiracy nuts is that they claim random physics professors know more about the situation than anyone. While they usually are brilliant, they are not structural engineers who deal with the requisite continuum solid mechanics regularly.

Have you read the report by the world's leading demolition company yet?

[/ QUOTE ]


Were they or were they not designed to take a large Boeing impact?

Someone thought it was a joke, then I pointed him towards this fact and then you start making a lot of noise. Do you have anything to say on the stated fact or not?

[Phil153]

Nielsio,

They were indeed designed to take a low speed 707 impact. However, the point is totally irrelevant, since THEY DID SURVIVE the full impact of a 767.

The structure didn't fail until an hour after impact, which the overwhelming expert opinion attributes to structural failure of the steel from the heat of a raging fire. If you want to debate that, do

How can you miss the point so spectacularly?

[Hopey]

[ QUOTE ]
Nielsio,

They were indeed designed to take a low speed 707 impact. However, the point is totally irrelevant, since THEY DID SURVIVE the full impact of a 767.

The structure didn't fail until an hour after impact, which the overwhelming expert opinion attributes to structural failure of the steel from the heat of a raging fire. If you want to debate that, do

How can you miss the point so spectacularly?

[/ QUOTE ]

It's pretty obvious that this is exactly the kind of stuff that he routinely intentionally ignores. Any evidence that doesn't fit with his conspiracy theory is immediately discarded. All that's left is a bunch of disjointed "evidence" that supports his crackpot theories.

[MelchyBeau]

The big reason the twin towers were meant to withstand a plane crash was because of a previous experience where a military plane (I believe a B-17) crashed into the empire state building in dense fog. Also because of the proximity of airports a danger would certainly be planes landing or taking off. These planes would not be flying at high speeds however they may be flying at low altitudes such as to potentially be a hazard to the twin towers.

A plane flying at the speeds of those that did hit the twin towers would most certainly be violating FAA regulations by flying that low at those speeds.

Even so the towers were built to be able to withstand a hit enough to the point to be able to evacuate the people out of the tower. If it wasn't for the fire we would have seen many more survivors. The fire trapped the people in the upper levels of the towers. The fire is what also caused the towers to topple, as they weakened the structure. Yes the plane impact did weaken the structure, but without the major fire the structure would be standing for a good amount of time to come.

[wacki]

here:
http://www.911myths.com/html/traces_...t_the_wtc.html

and here:
http://www.911myths.com/html/grimmer...d_the_wtc.html

and more here:
http://www.google.com/search?q=thermite+...lient=firefox-a

ok I'm bored.

[Bill Haywood]

[ QUOTE ]
[ QUOTE ]
Here's the sequential mechanism. One floor collapses 70 or 80 floors up, The entire weight of the part of the building above that floor falls into the floor below,

[/ QUOTE ]


Let me stop you there, as I think this doesn't match with the video footage. The video footage shows that the part above the impact zone collapses in on itself whereby the impact zone 'stays put'. Only after the part above the impact zone has collapsed halfway to 2/3rds does the whole thing start moving down from the impact zone.


[/ QUOTE ]

Why do you assume the collapse must initiate at the impact point? It was a huge fire. The collapse begins in a region that is on fire. Is that not strongly suggestive of fire-induced collapse? Where on that video do you define as the impact point, anyway?

The portion of the building below the distinct fire line clearly stays intact longer, until it is overwhelmed by the falling weight. This is not consistent with sequential explosives going off all the way down. It is consistent with pancaking.

Have you dropped the claim that explosives went off all the way down, and are you now saying explosives only initiated the pancaking that destroyed the building? We need a detailed sequential explanation FROM YOU.

Remember also that the outside shell of the building is structural (load bearing). So a collapse can begin inside the building, with the outer shell lagging behind because it is stronger. That can throw off our visual interpretation.

You've picked one tiny thing to respond to, while people carefully made many points the month or so ago when you were last active.

[PokeReader]

A couple of quick points.

1. The building absorbed the initial plane hit well. The Towers were a perimeter tube design, was one of the most structural redundant buildings ever designed. So when some of the columns were destroyed by the impact the adjacent columns absorbed the load.

2. The jet fuel burns at enough heat to burn steel inside a jet engine, but that is a very specific and completely different type of fire. In the conditions that were existing that day the fire probably reached about 750-800C. Not hot enough to burn steel, but steel softens at 425C and loses half its strength at 650C.

3. The day in question was a low wind day, and thus even with the fire and loss of some of the columns, the building was still capable of handling 2 to 3 times this load of stress. The problem was that the fire was not evenly spread thoughout the building. The variability in temperature of at least 150C in some of the long columns from the side facing the fire and the side facing away from the fire caused buckling failures.

4. The building collasped at a speed of about 200kmh, but not in freefall.

5. The fire retardant systems were operational, but not a significant impact against this type of fire, nor were they designed to be.

6. Neither aluminum, nor did any other metal reach liquid state. It would have been OVERWHELMINGLY visible through the fire. What was seen was probably just burning jet fuel.

Link to Journal of Minerals, Metals, and Material Engineering on 9/11.

http://www.tms.org/pubs/journals/JOM...agar-0112.html

P.S. As someone who was there, questions on dust and smoke coming out of windows too stupid to answer.