Although NIST does not draw attention to this fact, it now admits that of the three buildings to which it compares WTC 7, only two had shear studs connecting their girders to the floor slabs. This means that one of the other three buildings remained standing even though it had no girder shear studs. The argument for the causal connection NIST has suggested—between the absence of girder shear studs and global collapse—had become much weaker.
Nevertheless, after making this modification, NIST has continued to suggest the causal connection just as strongly as before. All of the above-quoted statements from the Draft Report, in which NIST called the absence of girder shear studs one of the factors responsible for the collapse of WTC 7, are repeated unchanged in the Final Report. NIST continues to suggest, in other words, that the argument for a causal connection is as strong as ever. There is, moreover, an even more serious problem with NIST's claim that the lack of girder shear studs was one of the reasons for WTC 7's collapse: In 2004—before NIST had developed a theory around the idea of girder failures—it had stated that shear studs did connect the girders to the floor slabs. In its 2004 Interim Report on WTC 7, NIST said:
'Most of the beams and girders were made composite with the slabs through the use of shear studs. Typically, the shear studs were 0.75 in[ches] in diameter by 5 in[inches] long, spaced 1 ft to 2 ft on center. Studs were not indicated on the design drawings for many of the core girders.'
Whereas the first sentence clearly indicated that shear studs connected most—but not all—of the girders to the floor slabs, the final sentence spelled out the exception: many of the core girders did not have shear studs.
This distinction is important because the crucial girder in NIST's 2008 theory—the one connecting Columns 44 and 79—was not a core girder. It was instead in the building's eastern region. According to NIST's 2004 report, therefore, this girder would have been anchored to the floor slab with shear studs—-at least 22 of them.
Why at least 22? The above-quoted statement says that the shear studs were placed from one to two feet apart. The girder was 45 feet long. So even if we assume that there was a shear stud only every two feet, there would have been 22 shear studs connecting this girder to the floor.
For its 2008 reports, however, NIST rewrote the above passage to fit its newly developed explanation of why WTC 7 collapsed. Its Draft Report of August 2008 stated:
'Most of the beams were made composite with the slabs through the use of shear studs. Typically, the shear studs were 0.75 in[ches] in diameter by 5 in[ches] long, spaced 2 ft on center. Studs were not indicated on the design drawings for the girders.'
As Chris Sarns, who discovered this contradiction between NIST's 2004 and 2008 reports, has pointed out, two crucial changes were made. First, whereas the 2004 report had said, "Most of the beams and girders were made composite with the slabs through the use of shear studs" [emphasis added], the 2008 version deleted "and girders," so only the beams were said to have shear studs connecting them to the slabs. Second, whereas the 2004 report said that the design drawings did not indicate shear studs "for many of the core girders," the 2008 report simply says that shear studs were not indicated "for the girders"—thereby implying that they were not indicated for any of the girders, whether they were core girders or not.
It appears, therefore, that NIST, having developed a theory that would seem plausible only if the girders were not connected to the floors with shear studs, has simply made those shear studs vanish. The girder connecting Column 44 and 79, therefore, went from having at least 22 shear studs to having none. How can we avoid the conclusion that NIST, an agency of the US Department of Commerce, is guilty of scientific fraud?
(The Mysterious Collapse of World Trade Center 7: Why the Final Official Report about 9/11 is Unscientific and False (Kindle Locations 4397-4412). Interlink Publishing. Kindle Edition. Griffin, David Ray (2012-12-30))
