New collapse simulation for the towers

[LSSBB]

This collapse simulation was just released. Looks kinda like what I pictured.

Opinions may vary.

 

[Oystein]

Before you show this to a Truther, get one thing clear:
Kostack does NOT model fires and their progression
Kostack does not model dynamic heating histories
Kostack doe not consider fuel distribution to guide his heating regime.

Because of all that, Kostack does not try to model the actual initiation sequence / event
Because of that, his model initiation is almost certainly different from the real initiation, and consequently, all that follows should not be expected to match in detail of location etc the real historical event.

Here is how Kostack describes the initiation sequence for his model:

The collapse trigger is a localized weakening of elements around the impact region, implemented as a spatially decaying gradient that reduces element strength and stiffness with distance from the centre of impact. In addition, a small number of core columns that engineering judgment indicated had suffered total failure after the impact were removed from the model; these removals are few and, taken alone, would not have produced global collapse. Trusses and façade elements in the affected area were also weakened. After this prepared initial state no further manual removals, scripted impulses or ad-hoc forces were applied: the sequence unfolds under gravity, inertia, contact and material response.

So, his model has a single center of heat input, which coincides with the "centre of impact".
In reality, much of the fuel and thus much of the heating was pushed towards the periphery of the impact area by the inertia of the plane debris and jet fuel.

INSTEAD the video should be presented as showing various mechanisms that played out during the collapse, such as the banana peeling of the walls, some pancaking, how the perimeter funneled the mass, how walls cut off floor trusses above or below depending on which side (inside or outside) of the corresponding upper/lower wall section they coming down. Oh, and how the top survives and supports Bazant's "Crush Down before Crush up" finding

 

[JayUtah]

So, his model has a single center of heat input, which coincides with the "centre of impact".
In reality, much of the fuel and thus much of the heating was pushed towards the periphery of the impact area by the inertia of the plane debris and jet fuel.

Not only that, an importantly significant portion of the thermal loading was provided by other combustibles. A simple spatial and/or temporal gradient from the impact area will not correctly model the thermal loads.