was it planned for the world trade center to collaspe the way it did. or did the planes just hit at the weakest point of the building. and also how could a building as strong as it was be tumbled by a plane hitting it.
2006-12-20 13:33:57 · 8 answers · asked by eca1094 3 in Science & Mathematics ➔ Engineering
Because the flames from all that Jet fuel, burned at thousands of degrees and engulfed the contents of the building. When the stuctural steel heated to thousands of degrees F the steel in the floors that were hit melted, and there were hundreds of thousands of pounds of wheight, furniture, people on the floors above which caused the upper floors to cascade down on the lower floors. The structure below could not take the weight and colapsed too. A sky scaper is nothing more than a steel cage Overlaid with glass. The intense heat of the jet fuel melted the bars of the cage and it all came down.
2006-12-20 13:41:24 · answer #1 · answered by stick man 6 · 5⤊ 0⤋
The building was not designed to collapse under NORMAL use. An aircraft being flown directly into the Towers in not a NORMAL event. The planes also had impacted the Towers from 2 distinctively different locations, so obviously they arn't the weakest points.
The reason for the collapse was due to the expansion of the floor beams. The expansion was from the intense heat of the jet fuel that was burning within the Towers. The expansion = coefficient of thermal expansion of material X change in temperature X length of the beams.
The floor beams reached a point where they couldn't take the enormous stress and yeilded. This occuring on one floor resulted in the next floor yielding, the next, the next and so on until the Towers were no longer standing.
2006-12-20 21:52:00 · answer #2 · answered by John G 1 · 3⤊ 0⤋
Had the buildings collapsed on impact, it might be said the the plane literally knocked them down. This did not happen.
It was a combination of the structural damage and the ensuing heat from the burning jet fuel that significantly weakened the remaining supports - the floors above than collapsed into the remaining floors and each collapsing floor just added more weight and impact to the floors under them. All of the building's weight was perpendicular to the ground - the resulting force was straight down. With no other forces acting on the building, it collapsed the same way - straight down.
2006-12-20 21:43:59 · answer #3 · answered by LeAnne 7 · 3⤊ 0⤋
The more mass above the point of impact, the more likely a collapse (due to impaired structural integrity). Couple this with temperatures far above the point where the remaining steel structures begin to melt, and you have a collapse.
A well planned piece of work by very evil people. I wonder if they would ever try to invest all that energy into building something, rather than just tearing down. Destruction is easy, creation is much harder.
2006-12-21 00:28:53 · answer #4 · answered by Frank M 2 · 2⤊ 0⤋
. The WTC was meant to stand under every load case which was considered for it. It was not designed to withstand several floors being simultaneously engulfed in flame. This caused sagging of the floor joists, pulling the ends of the floor joists of the perimeter beams attached to the columns. (I refer to horizontal pieces of steel as beams or, if the support a floor, joists. I refer to the vertical pieces, which transfer all the weight down to the ground, columns) When one floor dropped onto another one, which was also weakened the second one collapsed. The two floors falling together would probably have exceeded the strength of the floor joist connections on the next floor down even if it were not weakened by the heat. After that, the collapse was continuous and unstoppable.
. If you had said, before 9/11, that the floor connections should be designed to be able to tolerate the entire floor being heated to 1800° F, everyone would have looked at you like you were crazy.
2006-12-20 21:52:56 · answer #5 · answered by PoppaJ 5 · 3⤊ 0⤋
Yes. When they built they wanted it to fall straight down and not so it falls on other building and when the planes hit it the jet fuel melted the steel support beams so it cause it to fall that way.
2006-12-20 21:38:02 · answer #6 · answered by Anonymous · 2⤊ 2⤋
it wasnt meant to fall, it was a strong building. The hotness from the fire melted the beams which had fire proof stuff on it, it melted and made them weak, that's what caused it. Its sad that this has happened.
2006-12-20 21:37:57 · answer #7 · answered by citygirl22_1 3 · 3⤊ 0⤋
Yes, It was designed that way,so as not to topple down.Fire and shock wave blew insulation covering the beam's away causing
the fire to overheat fastener's(bolt's) causing the collapse.
2006-12-20 21:40:22 · answer #8 · answered by thresher 7 · 2⤊ 2⤋