NIST examines only 2 core columns from the collapse initiation zones
NIST noted in NCSTAR 1-3 that the core columns recovered from floors where fires were known to have occurred represent 1 percent of the columns in those areas. NIST did not find any evidence that any of the recovered columns experienced temperatures in excess of 250 degrees celsius.
Core Columns Exposed to Fire
Four of the core columns with known as-built locations were examined for mud cracking of the paint. For columns C-88a and C-88b, sufficient paint for analysis was not available. For columns HH and C-80, few areas of paint were observed (three to five spots per column) with no indication of temperatures over 250 °C. Note that these core columns represent less than 1 percent of the core columns on floors involved with fire and cannot be considered representative of any other core columns.
How many core column pieces were recovered from the collapse initiation zones of WTC1 and WTC2?
One from WTC2 and 2 from WTC1 from the locations marked:
Of the 94 (47x2) column sections which pass through the crucial 98th floor of WTC1, NIST managed to recover only one and you are looking at it:
C-88a and b:
These columns are interesting but it is the absence of the other 195 core column segments from the steel collection and the investigation which is much, much more interesting.
It is pretty obvious that for WTC1 careful examination of the 47 column sections spanning floors 98 to 101 and the 47 core column sections spanning floors 98 to 95 would show investigators all they need to know about the collapse initiation processes. Likewise, for WTC2, careful examination of the 47 core columns spanning floors 80 to 83 and those spanning floors 77 to 80 are very important to understand the WTC2 collapse initiation process. For example, if these columns were pretty straight on the whole, lacking significant signs of visco-plastic creep and buckled hinges, that would tell investigators that there was little collective core buckling.
James G. Quintiere, professor, Dept of Fire Protection Engineering, University of Maryland:
Spoliation of a fire scene is a basis for destroying a legal case in an investigation. Most of the steel was discarded, although the key elements of the core steel were demographically labeled. A careful reading of the NIST report shows that they have no evidence that the temperatures they predict as necessary for failure are corroborated by findings of the little steel debris they have. Why hasn't NIST declared that this spoliation of the steel was a gross error?
Created on 10/15/2010 07:09 AM by admin
Updated on 03/21/2013 09:37 AM by admin