Reply #56: I fail to see how you could so completely misunderstand. [View All]

[Make7]

janedoe wrote:
By the way, how long do you think they would take to fall if you used a safety factor of 5 instead of 1/3? A safety factor of 5 is more realistic of the building's design, don't you think? But, then, LARED's model wouldn't be able to show it could come down in 16 seconds... or even come down at all.

It is not a "safety factor" or a "fudge factor." That 1/3 represents the ratio of the energy expended by the collapsing building overcoming resistances compared to the available potential energy of the building.

Even if someone were to make a completely outrageous calculation of the collapse time, like 96.7 seconds, the ratio would not be greater than one. (It would be 99/100 for 96.7 seconds.) In his example, the energy expended will not exceed the available potential energy of the building. The "safety factor" will never have a value of more than 1. But I'm sure you already knew that.

-Make7