umm we mean...."representative/adequate steel sample in only determining the quality of steel". P3 Mechanical Analysis..
Paint study
• Paint condition used to map upper limits to
temperature exposure on 21 perimeter panels
�� Most perimeter panels (157 of 160 locations mapped)
saw no temperature T > 250 °C,
Findings – Forensic assessment
• Of the more than 170 areas examined on the exterior panels, only three locations had a positive result indicating that the steel may have reached temperatures in excess of 250 ºC.
despite pre-collapse exposure to fire on 13 panelsThe NIST found themselves to be in quite a pickle after the above Metallurgical Results had attested to temps of less than 250c in Oct of 2004. These findings had explicitly contradicted their long held theory which stated the fires had heated the WTC members to temps of 550c and above thus causing the affected steel to lose half of its strentgh ultimately leading to failure (*Even if that were the case that wouldn't explain the collpase, for the steel was prorated, thus even if the steel had lost half its strength it would still be able to bear its load)
So what did the NIST do?
Magic.
They, with a slight of hand, had changed their "adequate steel sample" from being adequate for the investigation (whole), to it only being adequate in determining the quality of the steel (final report).
The NIST did this even though in June 2004, before the "Steel temperature results" the NIST had clearly stipulated..
http://wtc.nist.gov/progress_report_june04/chapter2.pdf ---------The collection of steel from the WTC towers is adequate for purposes of NIST’s investigation (i.e., chemical, metallurgical, and mechanical property analyses as well as a substantial damage assessment and failure mode examination) to examine why and how WTC 1 and WTC 2 collapsed following the impact of the aircraft and ensuing fires.--------- As you can clearly see above, the NIST clearly states, the collection of steel was adequate for the needs of the investigation (whole) - Chemical, Metallurgical,and Mechanical property analyses as well as a substantial damage assessment and failure mode examination.
Moreover, the NIST details exactly what the Metallurgical Investigation consists of in other papers describing their investigation..
http://www.nist.gov/testimony/2002/wtcplan.html ----------Collection and Analysis of Forensic Evidence: structural steel, material specimens and other forensic evidence to the extent they have been collected or are otherwise available; metallurgical and mechanical analysis of steel to evaluate quality and estimate maximum temperatures; analysis of fire and elevator control panels.-----------------Hence, "The collection of steel is considered adequate for the needs of the investigation above"------- Just in case more evidence is needed..
http://www.aws.org/conferences/abstracts/2004/papers/2A... ----------NIST is implementing its technical plan to address these issues (see http://wtc.nist.gov /). A primary objective of the investigation is to determine why and how the towers collapsed after the initial impact of the aircraft. As part of this investigation, the Materials Reliability and Metallurgy Divisions in MSEL are studying more than 200 structural steel pieces from the WTC site. Progress in this study is outlined here..............
.......Task 3: Property data to support studies of structure performance and airplane impact modeling. Fourteen grades of steel were specified in the design of the WTC towers. All grades have been characterized for room-temperature mechanical properties, and initial high-temperature test results are complete. Testing at high strain rate is underway to determine the effects of strain rate on the mechanical properties of the outer columns, the inner columns and the spandrels. Chemical composition and metallographic examinations have been completed on the majority of the steels. Creep, or time-temperature-dependent behavior of some steels will be studied after the high temperature properties are developed.........
Task 5: Metallographic analysis of steel to estimate temperature extremes. Microscopic, macroscopic and metallographic analyses are under way to determine the maximum temperature excursions seen by the steel. -------------- Hence as was stated before regarding task's 3 and 5...
---The collection of steel is considered adequate for the needs of all the investigation So, as you can clearly see, the Metallurgical aspect of the investigation for which the steel was adequate, had clearly consisted in determining the quality of steel, and in determining the steel temperatures the steel was exposed to.
Last but not least, lets turn to the NAIL in the coffin.
The "Nail in the coffin" is evidence of the fact that the NIST had actually discussed changing their initial findings from the steel being adequate for the investigation to it being adequate to only part of the investigation (determining quality).
Note, the following discussion takes place on the very same day the results of the steel being less than 250c were to be presented - Oct 19th 2004.
http://www.nist.gov/public_affairs/ncstmin_oct19-20.htm ------------C: As John Barsom said, the statement is not accurate. The validity of the model question from yesterday speaks to this issue. I do not believe that we have enough forensic evidence. It may be okay to establish steel quality. There was no effort by the Building Performance Study team to systematically look at the steel.
C: The use of the term “adequate” needs to be revisited. There is no core column test to support the hypothesis. The floors came down, the slabs were pulverized. This was unprecedented. Exterior columns and core remained. The floors group will attack this finding--------------- "The use of the term "adequate" needs to be revisted", Science? I don't think so...
In summary, the NIST had only focused on one, and only one hypothesis/theory throughout its entire investigation, and that one hypo/theory being the assumption that fires were the cause of the two buildings(Three buildings-WTC 7) collapsing.
Focusing on a such a theory(blinders was the sole reason the NIST had ignored the metallurgical analysis results of the WTC structural steel . Over and over again, the wtc steel had indicated temps of less than 250c, which inturn naturally indicated fires not being the cause of the collapses, yet the NIST kept on with their assumptions and computer generated simulations via their assumptions that the steel had attained temps of 550c, even though there was not one piece of metallurgical evidence in support thereof..
In comparison, the general public are really no different than the NIST, for they have also concluded before sifting through the evidence that fires were indeed the cause for the buildings collapsing.
PS...
See Nist Appendix D
Comparing the results from the two analyses, some discrepancies exist where the visual observations made by WJE were in opposition to that of the results of the paint mapping technique utilized by NIST. As most of the observations of sooting and paint damage made by WJE were corroborated by the fire exposure-time sequence maps, it may be that a degradation mechanism exists where the primer paint exposed to the pre-collapse fires was damaged (resulting in the visual patterns) without increasing the local temperature of the steel above 250 °C. Z: The above statement is explaining the discrepency with regard to what the WJE had observed (soot and paint damage) and what the NIST had mapped..In other words, the NIST had mapped an area that the WJE had observed to be damaged, as an area where there shouldn't of been steel temps of above 250c. Hence the nist goes onto explain that maybe there is a "degrading mechanism" that can damage the paint faster and keep the steel temps from increasing above 250c.
From there, we move onto another discrepency, and in all actuality, quite opposite of the preceding one...
Additional to the discrepancy between the visual observations of WJE and the paint mapping technique of NIST, there were seven panels where precollapse fires were observable, yet neither analysis technique indicated the exposure on the recovered panel. One example of this was from piece M-2 where images show fires/external flaming for over 16 continuous minutes on the 98th floor (Sec. 2.3.1). Fires for 16 minutes on 7 panels, yet no evidence of exposure over 250c?
In all reality, just one panel of steel from the fire area should/could be representative of all the steel in the Fire Area, since all the steel was primarily affected in the same way by the fires, that is to say..Fires for almost the same amount of time(give or take a few mins (16 to 20 minutes-dwell times).
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