North Tower Acceleration

[jesters]

48. Yes, really.

1) We are talking about the smooth motion of the upper block in its initial collapse stages. No visible decelerations as it meets the stronger, intact lower block. Indeed, it destroys itself. Where does the core structure go?

2) We are talking about a force that needs to destroy all the connections of 80 - 90 intact steel-framed stories, while pulverizing all contents at the same time, at the average rate of 0.17 seconds per floor. The upper portion of building does not have this energy through gravity. How could it? It did not free fall during collapse initiation. It did not free fall at any time. Right there, it does not have the energy to complete collapse, and it only loses energy through each successive floor gravitationally, as it must. On top of this, you are requiring it to pulverize all the building contents at the same time. This is never going to happen gravitationally. Further, the top portion has destroyed itself in the first three seconds of collapse. Where is the model for a debris-driven, top-down, total destruction of a steel-framed super highrise?

Please include in your reply an answer to the last question.