Originally posted by Wolfpack 51
In a metallurgical investigation, in order for the structure to fall evenly, a unified heat source would be needed to weaken the support members evenly to a point that they would become elastic, unable to support the above weight.
Actually there are a lot more problems with that above statement than the misuse of the term “elastic.”
Wolfpack seems to be confusing the concepts of metallurgy and structural engineering. Metallurgy is a study of the basic properties of metals, whereas, it is Engineering that concerns itself with how any why structures stand or fall.
The term “unified heat source” is somewhat nonsensical. I am assuming that wolfpack means that the entire floor would have had to have been heated evenly in order for it to fail.
This is not true. When a column is no longer able to support the load that it is intended to support, that load just doesn’t go away. It is transferred to the adjacent columns and structural members. In this process, the loads on the other columns and beams can change dramatically. A column connection that was designed to be in compression may be put into tension by the shifting loads. Beams that were once supported on both ends are now cantilevered, and so on. Once a sufficient number of columns were no longer supporting the loads they were intended to, those loads would have shifted to the other columns. But this shift would not have been even.
If all of the columns on one exterior wall buckled inward to the point where they were no longer supporting the loads above, those loads would have shifted to the nearest un buckled, undamaged columns. At some point, the demand on those columns will exceed their capacity and they too will fail. This causes the loads , plus the additional loads from the newly failed columns to transfer to the next undamaged column, until it too fails and so on down the line.
The thing is, once a certain point is reached, this happens fairly quickly. It just seems like it happens all at once.
Originally posted by Wolfpack 51At a precise moment the energy of the above weight would fall evenly and continue to the ground.
Like I said, .it happens so quickly that it seems to happen all at once.
Originally posted by Wolfpack 51
This is not possible with the fuel that was present.
The fuel has nothing to do with it. Not in the sense that you are implying. The fire was hot enough to weaken the core columns and to cause the floor trusses to sag. This in turn caused the exterior columns to buckle inward.
Originally posted by Wolfpack 51
Some members may have weakend, but not all of them to give the pancake fall that we witnessed. Without all members being close to the same measure of elasticity, the building would have not fallen evenly, nor to the ground.
I think you simply fail to truly appreciate the enormous loads these columns were carrying. Once a runaway failure started, gravity pulled the building straight down.
Originally posted by Wolfpack 51
If bringing a building down of this size was as easy as igniting Kerosene on a floor with some weight above it, why do engineers go to school to study physics and load bearing technologies to do precise demolition work?
In order to prevent damage to the adjacent buildings, like WTC 6 and WTC 7, The Winter garden, The hotel, the bank, etc.
[edit on 4-1-2006 by HowardRoark]
