There is evidence that the east facade of WTC 2 from the 80th floor downwards fell as an interconnected single sheet of unbuckled perimeter column sections. The spandrel plate connections and column-to-column bolt connections remained largely intact until far into it's fall or upon hitting the ground.
Proof:
In the following photo please notice the location of the mechanical room relative to floor 81 where the fires and airplane damage occured.
The mechanical room has noticably higher ceilings and wider, stronger spandrel plates than the other floors both above and below.
Half of the mechanical room perimeter wall (about 30 columns wide) was found about 500 feet from the base of WTC2 speared into the earth as seen in the next few images. The other half of the east perimeter of the mechanical room was lying just beside it.
They were pushed outwards and fell close to 80 floors. They were then speared into the earth with obvious extreme force.
Despite this, they held up well and exhibit no noticable buckling along their lengths.
Please notice that the original location of this section is easily identifiable by using the zig-zag pattern at the top of the sheet and the location of the mechanical room.
There is only one unique place it can fit in the image below: It is the entire right half of the perimeter wall. The broken spandrels on the right must be just along the NE corner of the building.
The original location is marked in red along it's top, blue along it's bottom. There is no other choice.
As odd as that may seem, it is the location at which they were found that is even more surprising.
The following photos will help us identify their location in the rubble.
This piece is marked in the upper red oval. The other half of the mechanical room perimeter is marked in the lower red oval.
This is the debris as it looked just after 9-11-01. The perimeter sections sit at the very end of what appears to be a large, rolled-out sheet of perimeter wall. It is, in fact, the entire east side of WTC2, about 60 columns wide (57 to be exact, excluding the cornermost sections).
We can pinpoint the location of the speared columns using the image below.
And where is the intersection of Church and Cortlandt? In the red oval below.
We can see the entire east face of WTC2 below floor 81 "peeled" away from the building, falling over WTC4, it's top edge (the mechanical room sheets) landing along Church Street.
The next image shows the extent of the east face lying over much of WTC4. The blue line is the base of the original building. The red oval on the far right marks the speared mechanical room section.
The center red oval marks an exceptionally wide and strong spandrel plate, as yet unidentified.
Clean-up operations have already cleared debris in the lower left corner of the photo but the size of the intacteast side of the building is obvious.
Even from the debris we can see that the spandrels split along the NE and SE corners of the building yet remained relatively intact between the corners.
We can also see the east side poeel away as a single sheet in video of the collapse.
The following clip shows a large sheet of intact perimeter columns seen falling away from the building after the "upper block" had escaped view.
http://www.youtube.com/watch?v=nLHGLI1Ihv0
Please note the visible perimeter sheet at 0:17 of this 0:21 second clip.
This sheet is the intact perimeter columns of the LOWER BLOCK falling outwards. It is not in freefall. It is being pushed outwards just as if it is just the top of an intact sheet peeling away from the building.
It is easy to see that the top columns are from the 78, 80th floor area. Therefore we expect to find (and do find) the tops of these columns among the farthest displaced debris directly to the east.
Once again, no collective buckling seen among the members of this sheet as they are seen in the rubble. The single sheet peeling away means that perimeter connections largely survived the initial peeling process.
The connections seemed to "fail" just along the collapse initiation area (the top bolt connections on the mechanical room sheets) and along the 2 edges of the east facade (NE and SE corners), hence the single sheet.
Created on 05/18/2008 12:56 AM by admin
Updated on 06/10/2009 03:07 PM by admin
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