behavior observed in videos of the collapse. The collapse could have started at Floor 16 and below and produced the same behavior (Section 4.6). It is our conclusion based upon these findings that the collapse of WTC 7 was a global failure involving the near-simultaneous failure of all columns in the building and not a progressive collapse involving the sequential failure of columns throughout the building.
Figure E.3 Finite Element Model of WTC 7 in SAP2000, as viewed from the south.
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