Never in history has a steel framed building collapsed from a fire, and on 9/11 it happens to 3 buildings?

Question

No plane hit building #7, a 42 story building, which contained the emergency center where the mayor,
Guiliani, was supposed to be, but he was not there.
Despite nothing hitting it, it collapsed straight down.
Why?
There were only minor fires on 2 floors.

Answer 1

I doubt the source of your information for the premise that no steel frame building has collapsed from a fire. I owned a 30,000 sq ft building that housed a machine shop and the office for that. When there was a fire that started in the office area, the oil line to the furnace burner for the furnace that was situated in the rafters above the office ruptured, oil was thermal vacuumed from the storage tank, sprayed and burned down one side of a metal beam that was designed to hold a 20 ton overhead rail crane. The uneven heating of this beam and the normal stresses it was under caused this section of that building to fall even though the crane was not installed, because the beam deformed. Most of the remainder of the building was gutted, but usable. That section had to be totally rebuilt.

'No plane hit building #7, '

I don't know why this building fell also, and was surprised when I learned a few days after the tragedy it had fallen. I can only conjecture that the small fires were only small when considered relative to the inferno of the Trade Center and were rather significant fires in their own right. Heat is an enemy to steel framed buildings -- it weakens steel tremendously, particularly when unevenly applied to a large steel beam -- and any of them can fall if the structural beams are significantly heated.

Edited thought.

Oh, yeah. I just read the other responses and I remeber the McCormick Palace fire in Chicago. I went to the Machine and Tool Makers show in Chicago which was supposed to be held in the new Palace in 1968 and 1972 but was agian held in the old stockyard warehouses (as before). Then in 1976 it was moved to the new expanded (wow, BTW) Palace. BTW, I am an engineer and do not speak of steel strengths and weaknesses without some knowledge. The question of a common foundation, the original design and the impact of the falling Trade Center towers are also possible significant factors.

In short -- The insinuation of your line of reasoning is bunk.

Answer 2

There are no exceptions - the buildings that collapsed on 9/11 did not do so "because of fire alone." Fact: Structural steel looses 50% of its strength at approximately 1100 degrees F. This is why the steel is coated with an insulation - to prevent excessive heating in case a "normal" fire breaks out. This fact is valid and verifiable with a minimum amount of research, is well known and is compensated for in the initial designs and building practices. Check out the video - the impact of the first plane blew right through the entire width of the building - very likely destroying much of the insulation that coated the steel support columns and the fuel and inevitable fire ignited everything in the immediate vicinity - including lower levels as the oxygen starved fuel that wasn't immediately ignited traveled down elevator, column shafts and damaged floors. Building WTC 7 was pretty much ignored during the chaos - the building was damaged from debris, the electric generators fired up when the electricity was intentionally shut off in the area because they were not disabled in all of the confusion and it is now theorized that the fuel storage containers and fuel lines were ruptured. Again, the ensuing fire and initial damage is most likely the cause of its collapse. From an engineering perspective, it's not really difficult to accept what happened and the reasons behind it. The difference between static structural stress and the instanteneous moment force generated by the impact of collapsing 50 stories onto an obviously weakened section of the building - well, simply put, if no other forces are present - the building is going to come pretty much straight down, the greatest force simply being gravity.

Answer 3

One: it was a unusual building, very high and heavy, with an usual construction technique (not a lattice, which is stronger).

Two: it was not just a fire. That was hit by an large airplane in addition to the fire. Most buildings have just the fire. For instance even in a war, most missles are much smaller.

Three: Other steel buildings HAVE fallen due to fire.
"As an example of the damaging effect of fire on steel, in 1967, the original heavy steel-constructed McCormick Place exhibition hall in Chicago collapsed only 30 minutes after the start of a small electrical fire."

http://www.wconline.com/CDA/Archive/24ae78779d768010Vgn
VCM100000f932a

www.interfire.org/res_file/pdf/Tr-097.pdf

On the morning of January 28, 1997, in the Lancaster County, Pennsylvania township of Strasburg, a fire caused the collapse of the state-of-the-art, seven year old Sight and Sound Theater and resulted in structural damage to most of the connecting buildings.

The theater was a total loss, valued at over $15 million.

pg 6/74

The theater was built of steel rigid frame construction to allow for the large open space of the auditorium, unobstructed by columns... The interior finish in the auditorium was drywall.

The article below lists others and explains more about it.

Answer 4

Didn't all three building have a common sub basement system and basic supports? I don't think anything like a passenger jet, with full tanks of jet fuel has ever hit a steel reinforced building, and then another which were connected together at the foundation. That tremendous heat would have weakened, if not melted some of the steel in those upper floors. When they began to collapse, it probably twisted everything underneath it like a cork screw.
The engineers should have an answer by now?

Answer 5

How many times in history did two jet planes plow into them and have jet fuel burn for hours? That is a level of heat that you would be hard-pressed to find created anywhere in a building. You do know that steel will soften if the temperature is high enough...right?

Answer 6

Well we could also say "never" has a passenger airliner hit the WTC! Let alone two, fully loaded with fuel for a coast to coast flight. The fact is there are firsts in everything and from these we hopefully learn.

As to #7, I read it was an older building constructed with very different technique. It simply succumbed to the "fall-out" and percussion from the WTC towers collapse.

Answer 7

Do you have any brain cells left from all the drugs you must have done to make a statement like this???? Never in history have 2 commerical jets hit 1 building before either!!! Did you ever research the facts of how hot it got inside the Trade Towers due to all the jet fuel buring(NOT 2 small fires!!!) Do a little real research before you come on make such a idiotic statement.

Answer 8

there is always a first-- there is always an exception to the rule -- there is always a combination of factors, speed, content, weight, and a zillion of other tech factors too numerous to name them all. the important fact is that it happened and you have to accept the fact and go on from there. hope it does help.

Answer 9

Does make you wonder, doesn't it? The fire wasn't hot enough to destroy the steel frame, the building should have been gutted.

Answer 10

The new propaganda video on google also compaired the fallout to pyroclastic flow.....so...i guess a volcano caused it.