Rath said:
libellule said:
hi Rath,
so weird
planes are on 1 side at 1 level and they will change the temperature of the whole building ? at the same rate ?
the vertical "demolition collapse" is REALLY intriguing to me
and can you explain me the tower 7 demolition ?
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It only requires the weakening of a single level for the building to collapse in that way, the one level collapses and that causes a chain reaction as each floor collapses under the momentum of the rest of them - the 'pancake' effect you can see in the videos.
The plane had enough velocity to spread fuel and fire throughout basically the entire level of the building which is all that was required.
Also I don't know anything about the collapse of tower 7, so you'll have to ask somebody else on that one.
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Just to add to your point ...
Very tall towers tend to be built within very limited tolerances because you can't build a tower to those heights and have them overbuilt; and this is simply because the weight of the building would be too large for the building to support itself. What this means is that every floor is (essentially) designed to support the weight of all floors above it (with some reasonable margin for error). As soon as the building above a floor collapses on it that floor will collapse under the force of the "falling" building above it.
The reason the twin towers fell in such a straight fashion is that the fire from the fuel in the planes would be hottest at the center of the building, which weakened the building the most at the center of the building. When these towers failed, the floors collapsed in the middle and created a "cone", and with the structure near the exterior of the building being in better shape as the building fell it pulled everything to the center of the building.
I realize I'm not doing the best job explaining it, but the (basic) point is that the towers falling the way they did makes perfect sense.
