Twin Towers Collapse
Various experts and engineers have been studying the twin tower collapse on September 11, 2001 due to terrorist attack by Al-Qaeda in the city of New York. They approach practiced by these experts include studying the World Trade Center towers collapse by examining the collapse step-by-step. This approach is helping experts in learning how buildings fail, and thus also find out the ways to built stronger structures.
The overview presented below provides detailed information regarding twin towers collapse and also lists the reasons behind collapse of twin towers. Let us take a look:
Impact of the Planes
The impact of the hijacked planes which hit the Twin Towers of World Trade Center was so strong that around 10,000 gallons of jet fuel proved to be enough to ignite an enormous fireball. However, this impact of the planes and the burst of flames did not resulted in collapse of twin towers right away. The World Trade Center twin towers had redundant design which means that the design was such that when one of the system stops working, another carries the load. There were around 244 columns in each of the towers. With some of the columns got damaged, the other towers could still be used to assist the building.
Heat from the Fires
The sprinkler system of the twin towers was badly damaged due to the heavy impact of the planes. However, even if this system had been working, it would not have been able to maintain enough high pressure to stop the fire. The remaining fuel leaked from the plane resulted in intense heat.
The fires initiated in a part and then it got spread over to other places. The fire which was ignited by the plane hitting the building covered the area of an entire floor almost very immediately. By this time, the destabilized floors began to collapse, and they became pancaked. In other words, the floors which fell down on floors due to increasing weight and momentum, devastated each consecutive floor below. With the weight of the plunging floors building force, the exterior walls collapsed down.