Buildings are designed to re-distribute loads from failing columns to other columns.
But what you are failing to realize is the architecture and structural designs of the building. You also fail to realize building was damaged during
the collapses to the towers.
WT7 had an enormous load transfer system in order to accommodate the CON ED substation.
What this means is that this tranfer system is supporting a great deal of the buildings weight without intermittent supporting columns to assist with
the distribution or weight. Without these intermittent culumns to assist redistributing weight if the system fails there is no way to redistribute the
weight, because there is nothing to redistribute the weight to.
It is not unreasonable to believe that this transfer system was damaged from the collapse of wtc1 in a way that severely weakened it but allowed it
to stand.
Look at the reported damage following the collapse of wtc1.
SW Corner Damage – floors 8 to 18
South face damage between two exterior columns - roof level
down 5 to 10 floors, extent not known
South Face Damage –
• middle 1/4 -1/3 width south face, 10th floor to ground
• large debris hole near center around 14th floor
• 1/4 width south face, above 5th floor, atrium glass intact
• 8th / 9th floor from inside, visible south wall gone with more
damage to west, 2 elevator cars dislodged into elevator lobby
Much of the damage listed above could have had a great deal of effect on the transfer system.
It may or may not of even needed fire to complete the collapse.
Sometimes all it takes is time.
If the structure of the building is damaged things settle while the buildings weight shifts.
Sometimes all it takes is time for an overloaded beam to bend enough to fail, not all failures happen instantaniously.
IIRC there are reports of the exterior walls buckling well before the collapse, indicatiing that there was plenty of structural movement well before
the collapse.
It boils down to a damaged load transfer system between the 5th and seventh floors that holds up a large portion of the building failing, once that
happens there isn't anything else holding up that section of the building which is what we see when the penthouse drops. This is significant because
as that section falls it is connected to all the other beams, as it falls it creates alot of lateral forces which would damage signifcant portions of
the remaining building, damaging connection points which would be critical in supporting the remaining building. Failing to find or keep the
equilibrium required to remain standing, the rest of the building falls.
