anomandar said:
I will agree with u and say that u could VISIBLY see structure damage.
In the case of WTC7 you could visibly see, hours before it collapsed, that the buildings structure was becoming unsound, it visibly bulges out around 2pm, and by 3:30pm it's bad enough the fire department evacuates it because they can see that the structure is failing. An hour or so later it comes down.
U will also have to agree with me that all 3 building collapsed into there own footprint... yes?
The twin towers didn't, each one leaned ove a bit in the direction of the structural failure, and fell slightly in that direction. Debris from the side that failed also hit the ground several seconds earlier than debris from the other sides of the building.
However, this had more to do with the building swaying over a bit in the direction of the failing side, it did not "topple" so much as leaned over and then came straight down.
This is consistent with increasing load on a weakened superstructure leading to the eventual failure of the superstructure on the weak side and the collapse of the whole building.
U would think that it would be possible that the building could fall over, or a big chunk could fall off
You're thinking of a different style of building, where the construction principles are based on compression and support, where the bottom part of the building holds up the top of the building, essentially one thing piled on another.
The video on this thread shows buildings of that type being demolished and shows how they come down in line with the supporting columns in the buildings; also in some cases the buildings can topple over as some supports survive but other supports fail.
The WTC buildings were not built on that principle, they use a different principle called suspension. In the WTC buildings essentially you have a great big metal frame leading up to a point at the top of the building and in a very real sense the whole building is then hung from that frame. It is more accurate to imagine that what you think of as the building--the floors and walls--is being supported from the top. There are compression style supports too, but they are not anywhere near strong enough to support the weight of the building. The load is carried by the metal frame that it's hung from.
It is not possible for this building to "topple over" since it is not supported by anything to tople from. It is hung. As a building that is essentially hanging from a frame, when the frame fails it will fall straight down, which is what it did.
This is only possible by taking out the center columns.
This is where you and our "expert" McLuhan are wrong: There are no "center columns" in the sense that you imagine. There are columns, and they bear some load, but the ovewhelming majority of load is carried by the superstructure from which the building is hung. When the superstructure fails the path of least resistance is straight down, as it is essentially
being dropped.
The planes crashed in half way up the building dividing it into three sections: an intact section below, an intact section above, and a weakened section in the middle. The frame around the weakened section gave way and the section above, that had been hanging from that frame, fell through the weakened section landing on the section below. From then on in the weight of the whole top section falling down smashes the frame below as it falls.
If you watch in slow motion you can see that at the building comes down there's a process of the frame failing several floors below the current "falling point", which is the frame below giving way under the weight of the falling building.
In any building built along that engineering principle there is no other way for the building to come down, other than straight down the way it did. It might bend, lean or, bulge as the superstructure begins to fail--as was visible in WTC7--but when it finally fails it goes straight down from wharever it was at the moment of failure.