9-11; how exactly did the towers fall down because of fire when they were made of steel?

When steel is kept at a temperature of over 800 degrees, it becomes annealed, this means it loses all it's hardened properties and goes back to a soft durable metal. It wasn't the crashing of the planes, it was the intense heat of the jet fuel burning that damage the structure of the buildings, causing them to collapse onto themselves.

Actually this has been discussed to death. Conspiracy theorists just choose to ignore any discussion that contradicts their thoughts. "steel melts due 2 very hot temperatures (fire), steel does'nt bend like rubber willy nilly just 4 the fun of it" Basic phisics: Steel does bend like rubber willy nilly when it is hot, not even at its melting point! This is a well known fact! look here http://www.youtube.com/watch?v=uFJa9WUy5QI&feature=feedu Perhaps it was the only steel building ever to fall from fire alone, but thats harldy surpirising when you consider it is the only steel building to be on fire for someting like 7 hours. PS no one will ever take you seriously when you spell 'you' as 'u' , 'somehow' as 'sumhow', 'comes' as 'cumz', 'someone' as 'sum1' I mean come on! If you want to convince people try to spell a little better than a 6 year old!

1. Steel does not have to melt before it fail. It will significantly weaken at the temperatures caused by burning jet fuel. 2. The bottom, undamaged part of the building failed when the top several floors fell on it. While the building was designed to support its own weight, it was designed to do so when its weight wasn't moving. Once it started falling it built momentum, which essentially amplifies the force. I would suggest you learn your "basic physics" from more reputable sources than random websites. Your local university library will probably have several books about the properties of structural steel. They'll also have some books on English grammar as well so that you can present a readable argument.

This is a very useful book used by engineers who do fire sdesign for steel frame buildings. It contains good information we use for design. Not the crap the 9/11 Truthers are feeding you. http://www.tatasteelconstruction.com/file_source/StaticFiles/Construction/Library/Fire%20resistance%20of%20steel%20framed%20buildings.pdf (Note the graphs on Page 16. How the steel loses strength with temmprature.) http://fire.nist.gov/bfrlpubs/build04/PDF/b04047.pdf http://wtc.nist.gov/ Could the US Air Force (or Navy) destroy a high rise, curtain wall, steel frame commercial office building with a single 2000 pound MK-84 bomb (1230 pounds of TNT) plus 220 Mark 77 Incendiary bombs (24,000 gallons of Jet A fuel)? If the US Air Force or Navy attacked a building with a MK-84 and 220 Mark 77s and scored direct hits with all 221 bombs, how much of the building would you expect to be left standing? (You may assume that none of the Mark 77s hit the steel structure of the building. The Mark 77s just burned and started fires.) American 11 – Boeing 767-223ER http://en.wikipedia.org/wiki/Boeing_767#Specifications Fuel: 24,100 gallons (91.000 L) Mass: 179,170 kg Speed: Full Power, dive ~ 915 kmh 915,000 m /hr / 3600 s/hr = 254.2 m/s KE = 0.5 * 179,170 kg * (254.2 m/s)^2 KE = 5.79 * 10^9 J 1 lb TNT = 4.7 *10^6 J 5.79 * 10^9 / 4.7 * 10^6 = 1231 pounds TNT Compare to US Military MK-84 Bomb loaded with H6 explosive 945 lbs TNT * 1.36 to convert to H6 = 1,285 lbs TNT http://en.wikipedia.org/wiki/Mark_84_bomb http://www.youtube.com/watch?v=KfGYb0JsMeU http://www.smh.com.au/articles/2003/08/08/1060145828249.html American 11 hit WTC1 (North Tower) with the kinetic energy of a US Air Force MK-84 bomb. That is more than enough to bring down a high rise, curtain wall, steel frame commercial office building…. Or the US Air Force needs bigger bombs. Add to that 24,000 gallons of burning Jet A Fuel running down the stairwells, elevator shafts, and utility conduits. It is amazing the building stood as long as it did. Not, that it failed.

Actually, you have two choices. (1) Believe the studies that have shown thet the intense heat due to burning jet fuel weakened the building and it simply collapsed. You indicated you "studied it all" and yet you failed to address the impact of intense heat on the steel. Another recent example, have you seen the impact on metal structures in the recent Texas wildfire? Aluminum strucures simply melted. That was just due to the natural chemicals found in the trees. Imgine adding jet fuel. I too have studied the results and heard the stories and as a holder of advanced degrees in science I believe the collapsing building theory. Your second choice is simply not to believe and blame it on some other phenomenon or even a deep conspiracy by you name it. The facts will not alter your opinion so join the ranks of those that share your views. For this weekend however why not simply honor the memory of those that died in the towers, those that died trying to help, those that will die due to complications from the collapse and their families and friends.

it cud be dat it ther ws a double xplosion 1 frm da grnd 2knock its foundation and da planes as distractions coz jet is nt somuch acidic nd0an instant incrmnt in temp can nt melt da entr mtal colum

The interior exploded and collapsed.

They did bend, but that wasn't what caused the collapse entirely. Jet Fuel burns at around 800-1500 degrees. Steel burns at 2700 degrees, however it weakens at 1100 degrees. Because of this, and the fact that a plane had just crashed into the building leaving weak steel framing, the steel COLLAPSED onto the steel BELOW it causing a DOMINO effect that took the building down. What some people say is that other buildings have burned for hours and not fallen down, and people say how did the empire state building stay standing if that also got hit by a plane. Alot of people don't know that the Twin Towers were made from a WEAKER design than many other buildings, mainly to reduce cost, this is why the buildings were said to swing around when there was alot of wind. They were made with Internal STEEL COLUMNS The empire state building was hit by a smaller plane with LESS FUEL, was smaller than the twin towers and was made with heavy STEEL GIRDERS, all fireproofed, and was also made of heavy masonry construction. The Stairways were also fireproofed, so fire crews could get up to the top of the tower in just 40 minutes and dowse the flames. The Twin towers were fireproofed, however the type that was used was different to that used today and was simply BLOWN OFF because of the impact with the plane. The LIFT was also BROKEN in the Twin Towers meaning that fire fighters could not get up there fast and the stairways were flooded with debris so they could get up there either.