WTC destruction comparison matrix
9/11: WTC destruction comparison matrix
Overview
This page is for comparison of the following, with regard to the destruction of steel-framed high-rise buildings:
- common attributes of different causes of destruction (earthquakes, fires, explosions, controlled demolition)
- attributes found in the destruction of WTC1, WTC2, and WTC7 on 9/11
The Matrix
| CAUSE → | controlled demolition | earthquake | explosion | fire | BUILDING → | WTC1 | WTC2 | WTC7 |
|---|---|---|---|---|---|---|---|---|
| Attribute | ||||||||
| Center first |
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| Comparable size |
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| Deformations | ||||||||
| Ejection | ||||||||
| Movement | ||||||||
| Pulverization | ||||||||
| Recognizability | ||||||||
| Squibs | ||||||||
| Symmetry | ||||||||
| Toppling | ||||||||
Attributes
- Center first: the middle of the building begins collapsing slightly before the outside edges
- Comparable size: the rubble of the collapse is of a size/volume comparable to the original structure
- Deformations: notable deformations in the building's structure are visible before the onset of collapse
- Ejection: solid materials are ejected forcefully from the building during collapse, typically in a horizontal direction, landing some distance away from the main body of the post-collapse structure
- Flashes: faint flashes of light are seen shortly before and during collapse
- Free-fall: building collapses quickly; technically not "free-fall" speed, but within an order of magnitude
- Pulverization: large volumes of dust are produced
- Recognizability: after collapse, the building is still recognizably the same structure, albeit severely distorted by the collapse. Basic structural frame is still holding together.
- Squibs: small puffs of dust or smoke seen shortly before onset of collapse or during collapse
- actually a slight misnomer; the term "squib" technically refers to the devices which cause these puffs – but within the context of this discussion, we'll use it to refer to the puffs themselves
- Symmetry: the building collapses nearly symmetrically, rather than from one side first
- Toppling: the building collapses on its side, with significant horizontal displacement and deviation from the vertical
Also need one or more attributes having to do with the characteristics of fire: evidence of extreme heat, color of smoke, degree to which building is engulfed in flame. Note that fire has never caused collapse of a high-rise.
Molten iron
Causes
- Controlled demolition: rapid onset, symmetrical, collapses from bottom, collapses inward into its own footprint, collapses quickly, squibs above point of explosion, clouds of dust and smoke, center first, collapsed building unrecognizable / no integrity, small chunks, molten iron often found (from thermite)
- Earthquake: asymmetrical, toppling, recognizable integrity
- Explosion: thick, dense, billowing, enormous clouds of dust and smoke, flashes of light, explosive sounds
- Fire: (has never caused a high-rise to collapse, so only examples are from smaller buildings)
Queries
The most rigorous way to pursue this analysis would be to have a complete list of all known steel-frame building collapses which have been described in any detail (or for which there are images or videos), and come up with a correlation between each cause-of-collapse and each collapse attribute. It would then be possible to calculate, with a reasonably small margin of error, the likelihood of each possible cause-of-collapse being responsible for each of the three collapsed WTC buildings.
I don't know where to find such data at this time, but one can certainly begin compiling a list of steel-frame building collapses along with any details known.