Reply #20: "Mud cracking" method of max temperature evaluation. [View All]

[Carefulplease]

Edited to fix bold tags.

(3) The paint cracking method only worked when there was enough paint remaining to perform the analysis. This was seldom the case. Most often there was no paint remaining at all. This skewed the results since the column areas exposed to the most extreme temperatures and to aircraft debris impacts weren't likely to have had as much paint remaining on them as other samples had.

Again, I have to ask you exactly what evidence you can supply that supports this wild theory of yours. For example, what perimeter columns were examined that had "no paint remaining at all"? The answer, of course, is none whatsoever.

That is not a theory of mine and the claim isn't wild at all. I do not know how many (if any) full panels (columns-trees : 3 columns x 3 floors) had no paint remaining on them at all. Only panels with known as-built location were selected. Areas on those panels were selected for mud cracking analysis on the basis of the paint condition. They were selected "provided that sufficient paint was available for the analysis". Mechanical damage would also produce mud cracking. However this would result in directionality in the pattern. Such samples were "dismissed" (NISTAR1-3C p. 219.)

Four core columns were examined. Two of them had no sufficient paint available anywhere on them. The other two had "minimal" paint on "three to five spots per column". The cause of the loss of paint was not determined and could have been due to "pre- or post-collapse temperature excursion, ambient corrosion subsequent to collapse, or mechanical damage". (My emphasis)

http://wtc.nist.gov/NCSTAR1-3Cchaps.pdf
pp. 219-220