Some Misunderstandings Related to WTC Collapse Analysis

[Tony Szamboti]

So Danny.... what would a natural collapse of a huge skescraper look like?

I think many people might accept that buildings may collapse due to fires and mechanical and structural damage though the evidence is very debatable....since it has never happened except on 911...however, for many, it is the way the buildings fell down. They fell down and not over. They fell into their own foot print. The damage was asymmetrical and one might think the collapse would also be asymmetrical. Which it wasn't in all 3 buildings. And the damage and impact areas were different in all 3 buildings but the collapse was pretty much the same.

Magda,

It is the nature of mass distribution in such structures that they will ALWAYS collapse down as we saw. The are not strong enough to "knock over". The stand because of mass is supported axially by columns. A cantilevered structure would tip over. These were not. These HAD to come down.

The so called asymmetries of the damage in the consideration of the mass were not enough to influence the downward vector of the gravitational force.

Note that the top of WTC2 began to tip. But at the same time, I can assure you it was also dropping and colliding into the structure below. And as it tipped it was coming apart inside. as the frame was not designed to perform at such angles. When tipping he columns' strength becomes subordinate to the connection strength... that is... as a structure like the top tips it is the connections of the frame must hold it together for it to move as a "block". Those connections are not strong enough and failed and the frame inside came apart along with the floors it support. When that happened gravity ruled and the mass dropped straight down. So within a few seconds the tilting top completely came apart...and turned into the ROOSD mass.

There is still an asymmetry problem in the south tower. Where was the force generated to vertically collapse the lower section of the building on the backside of the tipping upper section? Most of the force would be on the front side of the tipping section which is in compression, but the backside is in tension, yet the lower section on the backside collapsed uniformly with the front side.