Total Building Collapse from a Single Column Failure

NIST makes the case that the failure of column 79 on floor 13 apparently caused by a girder walking off its beam seat at column 79 led pretty quickly to the collapse of the entire building leaving nothing standing at all.



I wonder... how universal this actually is?



Would column 79 failing at floor 29 have caused the global collapse?



Would any other single column failing on any floor lead to global collapse?



Could any single column failing on any other floor NOT lead to global collapse? (I don't suspect the failure of a column at the roof level would.) If so why or why not?



Is this single column failure applicable to any multi story high rise? Would it have to be steel framed? Would it have to be a minimum building height? Would there have to be a minimum number of floors above the failed column?



If the single column failure global collapse outcome is not more or less universally applicable what was it about 7 WTC's design and column failure at floor 13 that allowed for a single column failure to lead to global collapse?



Should NIST have discussed this or not?

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