This diary is not a conspiracy theory, I repeat, not a conspiracy theory. Rather, it is an analysis of the NIST's final report on what caused the collapse of WTC7. And while some people say that its time to move on to other things, I disagree because NIST is presenting a brand new hypothesis, and it deserves some critical analysis. Also, the timing is suspect, coming out right before the Democratic primary so people would forget about it. Well, I say let's not forget.
After reading the NIST press release and final report, the explanation of how a chain reaction total collapse was started by the failure of one floor girder seems both a wild guess and absurd on its face.
NIST press release
NIST Final Report on the Collapse of World Trade Center Building 7
Supposedly, one floor girder between interior/core column 79 and perimeter column 44 on the 13th floor failed (see floor plan in press release above). This was due to what the NIST calls thermal expansion. The NIST has almost no forensic evidence for believing this happened, but lets give them the benefit of the doubt. Lets say this girder expanded and collapsed, and also accept what NIST says happened next, that the northeast corner of floor 13 (bottom left corner in floor plan) then collapsed which crashed down and collapsed the section of floor beneath it on floor 12, and this repeated all the way down to floor 5.
OK, this is where the NIST theory gets supremely absurd. Supposedly, the collapse of the girder and corner section of floor on floors 6 - 13 caused column 79 to buckle (i.e., bend and then break apart). Also, this happened due to column 79 losing "floor support". First, floor girders don't support columns. Rather, columns, the steel pieces that go up and down, support floors. At least that's the way gravity and structural engineering have always worked in the reality-based world.
Moreover, column 79 was an interior/core column. It has columns adjacent to it on all four sides. So, even if the girder connecting column 79 to column 44 failed, there were still three of the four sides that were still just fine. These three remaining sides' braces provided plenty of rigidity and structural support. And to keep things in perspective, column 79 was 47 stories high, so 39 floors lost none of these structural connections, while 8 floors lost only one of four structural connections.
Also, what makes the NIST hypothesis even more absurd is that there were really two connecting beams going in the same basic direction that the failed girder went (due to the trapezoidal corner shape of the building). There was the girder that went out to perimeter column 44 and another beam going out to the column next to 44. So this second beam would have helped handle the extra stress or tension of the failed girder.
Now does this sound like a situation where column 47 would buckle and break into pieces due to loss of "floor support"? Not to me. It sounds like more Bushit. If this first column never broke apart and collapsed, then the chain reaction never happened. And thus, NISTs entire hypothesis is wrong. Why NIST presented such a half baked theory of total collapse based on one failed girder is beyond me. I will let others speculate. But there is not a chance in hell the NIST hypothesis is correct.