See Excerpt Below, View the entire list here.
WTC 7 – THE THIRD SKYSCRAPER
- OMISSION OF GIRDER STIFFENERS SHOWN ON FRANKEL DRAWING #9114
Technical Statement: NIST maintains that WTC 7 collapsed due to fire acting upon the 13th
floor A2001 girder between columns 79 and 44 and the beams framing into it from the east.
They said that the beams expanded by 5.5” (revised in June 2012 to 6.25”), broke the girder
erection bolts, and pushed this girder off its column 79 seat. This girder fell to floor 12,
which then precipitated a cascade of floor failures from floor 12 down to floor 5, and
column 79 then became unsupported laterally, causing it to buckle. It is then said that
column 79’s buckling caused the upper floors to cascade down, which started a chain
reaction — a north-to-south then east-to-west horizontal, progressive collapse — with a
global exterior collapse that was captured on the videos.
The first omission concerns flange-to-web stiffeners on the south end of the girder (A2001).
See drawing 9114. These omitted stiffeners would prevent the girder flange from folding
when the girder web moved beyond the seat, requiring twice the possible expansion of the
beams framing into the girder from the east to move the girder far enough to the west for it
to fall off its seat.
References:
? Frankel Shop Drawing #9114 https://www.dropbox.com/s/r009pjr3qhduyjg/9114.TIF?dl=0
o Girder_A2001_Stiffeners_Plan_HL
https://www.dropbox.com/s/jnt2f9i2vnm0wa3/Girder_A2001_Stiffeners_Plan.jpg?dl=0
o Girder_A2001_Stiffeners_Elevation_HL
https://www.dropbox.com/s/uy7cehcn2saorh1/Girder_A2001_%20Stiffeners_Elevation.jpg?dl=0 - OMISSION OF THREE LATERAL SUPPORT BEAMS ON THE 13TH FLOOR G3005 BEAM
Technical Statement: NIST omitted three lateral support beams from the exterior frame to
the north-most beam (G3005) framing into the A2001 girder between columns 44 and 79
from the east. The NIST WTC 7 report contains a second possible failure initiation
mechanism, where G3005 buckles and causes the other four beams framing into the girder
from the east (A3004, B3004, C3004, and K3004) to also buckle, lose their load-carrying
capability, collapse downward, and rock (pull) the girder off its seats back to the east. When
these lateral support beams are excluded in the NIST analysis, the beam slenderness is
increased by 16 times, and this reduces the actual buckling load to 6% of what it would have
been in reality. Analysis with the lateral support beams included shows that the beam
would not buckle and that it would actually deflect the girder and put the other four beams
in tension, eliminating any chance of them buckling, as beams and columns need to be in
compression in order to buckle.
References:
? Frankel Shop Drawing #3005 https://www.dropbox.com/s/qoikgin4l8x0yub/3005.TIF?dl=0
? Frankel Shop Drawing #3007 https://www.dropbox.com/s/f9n62mr3c1mdvqs/3007.TIF?dl=0
3
Rev. 4/9/15
? Frankel Shop Drawing #9150 https://www.dropbox.com/s/2fne2vd75p0yjcy/9150.TIF?dl=0
? Frankel Erection Drawing #E12/13
https://www.dropbox.com/s/0rw4w6hc1ih8g2t/Erection_Drawing_1213.jpg?dl=0
Download and read the entire paper here.
