Creative Speculation
Related: About this forumShear Ignorance NIST and WTC7
The first video examines the precursor to NIST's theory of connection failure. First of all, because NIST's theory needed the composite floor in that area to fail, NIST blamed its failure on the absence of shear studs on the critical girder. We look closer at that claim.
NIST and WTC7 The Expanding Lie
The second video looks into NIST's thermal expansion theory and its effect on the steelwork of Floor 13. We discover many key errors in their calculations.
Tangled Webs NIST and WTC7
In the third video, we introduce new information about the true makeup of the connection between Column 79 and the critical girder. Had the correct items been included, NIST would have been forced to consider a different conclusion.
NIST and WTC7 maladmiNISTration
The fourth video originally was a summary of the earlier information, but soon after our third video revealed NIST's "error," NIST issued an "erratum document" which lists errors they claimed to have found in reviewing the Final Report. This document is included in our video, and as you will see, the information provided by NIST only further clouds the issue.
Link to NIST erratum document: http://www.nist.gov/customcf/get_pdf.cfm?pub_id=901225 (Link says unavailable due to government closure)
Kennah
(14,465 posts)JohnyCanuck
(9,922 posts)Seems to think that NIST's failure to acknowledge the presence of the girder's steel stiffener plates at column 79 is the final nail in coffin for the NIST report on the WTC 7 collapse.
WTC7 - The Stiffener Plates Explained
See also the comments on this thread:
http://911blogger.com/news/2013-09-29/stiffener-plates
William Seger
(11,082 posts)Sorry, I'm having trouble understanding how those stiffener plates could have prevented the girder from being pushed off its seat. Please explain it to me in your own words.
Ace Acme
(1,464 posts)The girder has maybe 35 square inches of bearing surface on its seat.
When it's pushed half way off, it has only 17 square inches of the flange bearing on the seat, but the web is
still bearing on the seat.
When it's pushed 3/4 of the way off, it has only 8 square inches of bearing, and the web is off the seat.
At this point, the overload of the flange on an unstiffened girder will cause the flange to bend upward,
facilitating the push-off.
With the stiffener plates on, you have to push the girder all the way, 100% of the way off the seat, before it
falls off.
Of course with the shear studs on the girder it's not going anywhere anyway, but what's the fun in that.
We're all going to pretend there were no shear studs, aren't we?
William Seger
(11,082 posts)Last edited Wed Oct 23, 2013, 11:12 PM - Edit history (1)
The video claimed to be showing that the NIST hypothesis was impossible, but the actual NIST hypothesis does not include any supposition that the flange collapsed when the web went past the edge of the seat plate. It's ironic that elsewhere you accuse others of "straw-man arguments."
Ace Acme
(1,464 posts)should it come out that NIST's calcs exaggerate the amount of push given by the thermal expansion.
NIST refused to release their calcs, so they had no need to employ that particular fudge factor.
They put their thumbs on the scale every step of the way.
William Seger
(11,082 posts)Again: The video claimed to be showing that the NIST hypothesis was impossible, but the actual NIST hypothesis does not include any supposition that the flange collapsed when the web went past the edge of the seat plate.
After jumping in but failing to refute that statement, you'd now like to make a different claim: Even though you can't explain why the stiffener plate makes any difference whatsoever to the actual NIST hypothesis, you're pretty sure they deliberately omitted it for some nefarious purpose?
Ace Acme
(1,464 posts)Last edited Thu Oct 24, 2013, 04:43 PM - Edit history (1)
you start to suspect that they're done for a purpose.
Especially in the case of building 7, where it took them 6 years to cobble together their explanation.
Deformation of the girder flange may not be cited in the NIST report, but the idea that it was possible makes their walk-off explanation more plausible than it would be if the stiffener plates weren't there.
I'm relying on memory here, and I never was an expert on this issue, but I believe that independent calculations of the thermal expansion show that the girder will not be pushed all the way off its seat.