*facepalm*
please take construction class and building safety class before you say anything more ridiculous as what you have said! the buildings including WTC were built lightweight meaning that deadweight had to be LIGHT. No one calculated in the new airplanes. WTC buildings were BUILT to withstand a full force of impact of 1960s and 1970s jets and passenger planes. If you do not know what the dead-weight is, look it up. The buildings were NOT built to withstand a full airplane loaded with jetfuel. Believe me jetfuel IS HOTTER much hotter than gasoline. Gasoline evaporates where as jet fuel boils at 349 °F but it burns at 800° to 1500° F. If you havent taken chemistry class, you should take that as well. WTC's steel is a regular commercial Reinforcement steel which is 98 % Fe, 1 % Mn, 0.2 % C, 0.2 % Si. FE stand for IRON! Iron's melting point is 2,800 F. 3,500 gallons of jet fuel burned in each tower. There are 244 columns in each tower. Because FE loses its strength due to oxygation and at 1,200° F, it loses half of its strength and with increase temperature the molecules and atoms expand at the higher speed *PHYSICS* Iron withstood Oxygen because both of them have 2 atoms per molecule. What brought the buildings down was the temperature shock of the fire infecting the entire building NOT the steel. The steel stood and did its job but the rest of the materials that were used in construction COULD NOT and i repeat COULD NOT withstand the temperature of jet fuel.
Concrete turned into DUST because it CANNOT withstand high temperatures. It is a cold water based material a mixture of broken stone or gravel, sand, cement, and water. What happens with water when it is in contact with fire? it evaporates. Physics 101. ever seen concrete machines making concrete? what is the drum mixing? WATER! i believe limestone was used in WTC because it is LIGHT and crumbly. You cannot build WTC building in granite. Pressure per foot will be insane. That is why people who actually work with stone and remodeling kitchens and bathrooms try to avoid limestone in the kitchen as counter-tops .. that **** does not do well with water and fire. it just turns into dust.