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Origin of the paint that was found as red-gray chips - any ideas?

chrismohr said:
This may be a mistake. We need to heck again because Jenkins's complaint may have been the the aqueous solution was left in the fridge too long, thus reducing its pH... NOT that it was liquified.
Click to expand...


Well until you have clarification from Jenkins I'll give this the benefit of doubt and just treat it as Jenkins having worded it badly.
 
oystein said:
update on our laclede paper, tentatively titled

red-gray chips in the dust of the world trade center
collapses: A new interpretation​

ivan kminek, who will feature as co-author, is currently reviewing the last draft version (enigmatically numbered "v.0.64") before i send it out to a group of other reviewers. It's currently 34 pages long, with 43 footnotes, 18 figures, 26 referenced documents, and the following colclusion:

in summary, we conclude that the red-gray chips (a)-(d) described by harrit e.al. Are not thermitic. They are laclede standard primer (red layer, with iron oxide, aluminium silicate and strontium chromate pigments) on oxidized structural steel.​
Click to expand...

LET THE HAND-WAVING COMMENCE!!!

....Note like it hasn't already started.
 
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jaydeehess said:
Well until you have clarification from Jenkins I'll give this the benefit of doubt and just treat it as Jenkins having worded it badly.
Click to expand...

I think it's pretty clear that Jenkins' complaint is as Chris describes it: not that creating a solution alters the pH, but that the pH can change when the solution is set aside for several days.

However, if the study is read closely, before testing the samples for pH, the Rutgers team first added water to the samples, inverted the tubes several times, soaked them "several days" at room temperature, and then stored them in the refrigerator for an unknown time period before pH testing.
Thus, by their own admission, the Rutgers research team was intentionally and deliberately neutralizing the samples before testing the pH.

Jenkins, p. 11
Click to expand...

From that alone, you can't tell exactly what she is arguing (and that last sentence is unreasonable). But in what follows, she makes the case that the time delay matters.
 
jaydeehess said:
Correct me if I am off base on this but doesn't Jenkin's repeated complaint that the samples were put in solution prior to ph testing completely destroy any authority and expertise she might claim and thus make her critique not worth the paper its written on?
Click to expand...

I honestly don't know, as this is not something that I would use, but maybe Ivan or one of the other more lab type guys may know....
 
MarkLindeman said:
I think it's pretty clear that Jenkins' complaint is as Chris describes it: not that creating a solution alters the pH, but that the pH can change when the solution is set aside for several days.



From that alone, you can't tell exactly what she is arguing (and that last sentence is unreasonable). But in what follows, she makes the case that the time delay matters.
Click to expand...

Again, if I have ignored some important issue forgive me. pH depends on concentration (the amount of substance per unit volume of solution), ergo the sample must be in solution for determination of pH. Had the samples been in contact with the atmosphere for a few days, a strongly basic solution would undergo a change in pH due to reaction with acidic (atmospheric) carbon dioxide but I would have expected that the solutions would have been protected (by a simple rubber bung!); this would have prevented substantial pH change.

Besides the measured pH depends (precisely) on the volume of water with which one prepares the solution. Use 10, 50, 100 mL, 10L volumes you progressively decrease (i.e make more neutral) a given quantity of basic metal salts. Maybe there is a standard protocol for these things - I don't know it.
 
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Sorry that I didn't go past that (poorly written) paragraph in the beginning, but I took a look at the rest later and indeed Jenkins complains about the time for analysis, citing a paper from... 2006! that shows that the pH of concrete drops over time even with the sample isolated from the atmosphere between measurements.

She also complains that a protocol released on November 2004 about waste and soil (?) analysis, which mentions realizing the measurement of pH «as soon as possible», wasn't followed by the Lioy team in 2002 or in May 2004 when they analyzed the WTC dust.

If anyone is to blame, it's the maker of the crystal balls used by the Lioy team.
 
Estimate of structural steel primer paint areas (in square feet) for WTC1,2
Note: For WTC1,2 - no floors outside the core at 1-6, 8,42,76,109

Laclede primer-[1] primary and bridging floor trusses at tenant floor areas outside the core.
6,440,000 sq.ft. total surface area for Laclede trusses for both towers.

[1] Primary floor trusses per floor; top chord angles (2) 2”x1.5”; bottom chord angles (2) 2”x3”; web 1.09” dia webs center to center 3.33 feet o.c.; truss depth 2.42 feet;
Chords = 34” * 12” = 408 square inches of painted chord surface area per foot of truss + 78 sq inches per running foot of truss for web surface area = 486 square inches / 12”/ 12” = 3.38 square feet of painted chord and web surface area per running foot of truss * 60 feet long span * (2) trusses * (58) pairs of long span trusses = 23,525 sq.ft. of surface area long span trusses per floor.
+ Short span trusses: 3.38 square feet of painted chord and web surface area per running foot of truss * 35 feet long span * (2) trusses * (28) pairs of short span trusses = 6,625 sq.ft. of surface area short span trusses = 30,150 sq.ft. total of surface area primary trusses per floor.

[1] Bridging floor trusses per floor (perpendicular to primary floor trusses) top chord angles (2) 1.5”x1.25”; bottom chord angles (2) 1.5”x 1.25”; web 1.09” dia webs center to center 2.5 feet o.c (estimate).; truss depth 2.0 feet;
Chords = 22” * 12” = 264 square inches of painted chord surface area per foot of truss + 78 sq inches (estimate) per running foot of truss for web surface area = 342 square inches / 12”/ 12” = 2.38 square feet of painted chord and web surface area per running foot of truss * 207 feet long span * (8) trusses = 3,941 sq.ft. long span.

2.38 square feet of painted chord and web surface area per running foot of truss * 87 feet short span * (4) trusses = 828 sq.ft.short span.
3,941 sq ft + 828 sq ft = 4,769 sq.ft. total surface area bridging trusses per floor.

[1] 30,150 sq.ft. + 4,769 sq.ft. = ~35,000 sq.ft.primary and bridging trusses surface area per floor * (110 floors - 8 beam framed mechanical floors - 4 no mechanical floors (double height) - 6 no lobby floors = 92 truss framed floors) = 3,220,000 net sq.ft. trusses surface area per tower * (2) Towers = 6,440,000 sq.ft. total surface area for Laclede trusses for both towers.

Tnemec 99 primer perimeter cols above 9th floor, Tnemec 69,95 4th-9th floors-[2] Perimeter box columns, spandrel plates
4,340,000 sq.ft. perimeter columns and spandrels for both towers.

[2] Perimeter box column; 16” inner x 14” x 14” x 14” other sides. 16” +16” +14” +14”= 60” surface *12 ft. *12 in. / 12” /12” = 60 sq.ft. per column per story - (area covered by spandrel plate 6.5 ft * 1.33 ft = - 8.7 sq.ft.) = 51.3 sq.ft. * 236 columns *110 stories = ~1,332,000 sq.ft. perimeter columns surface area one tower.

[2] Spandrel plate inside surface. 6.5 ft x 3.33 ft = 21.65 sq.ft. per column per floor + outside surface 21.65 sq.ft. - (8.7 sq.ft. column overlap area) = 12.95 sq.ft. = 34.6 sq.ft. inside + outside spandrels per column per story * 236 columns * (110 floors - 6 lobby floors = 104 floors) = ~ 849,000 sq.ft. of spandrels surface area inside and outside one tower.

[2] 1,322,000 sq.ft perimeter columns. + 849,000 sq.ft. spandrels = ~2,170,000 sq.ft. of Tnemec primer perimeter columns and spandrels * 2 Towers = 4,340,000 sq.ft. perimeter columns and spandrels for both towers.


Unknown primer-
[3] Core box columns,
[4] Core wide flange floor framed beams,
[5] Wide flange framed floors outside the core (mechanical floors- 7,8,9,41,42,43,75,76,77,108,109,110,roof) ,
[6] Hat truss framing (floors 107-110),
[7] Core cross bracing at all mechanical floors and lobby atrium and miscellaneous steel (plates, angles, channels)
Total Unknown primer = ~1,780,000 sq ft * 2 Towers = ~ 3,560,000 sq ft

[3] Core box columns; 1.33 ft x 3.0 ft = 8.66 ft perimeter * 12 ft high * (47) columns * 110 stories = ~537,000 sq ft surface area.for one Tower [3]

[4] Core wide flange floor framed beams; W16x40 (guesstimate) 7” x 16”= 3.83 ft ; 3.83ft * (8) * 135 ft = 4,136sq ft + 3.83 ft * (14) * 87 ft = 4,665 sq ft;
Total = ~ 8,800 sq ft total core framed floors * 110 floors = 968,000 sq ft per Tower.[4]

[5] WF framed floors outside the core (Mechanical floors 7,9,41,43,75,77.108,110,roof-9 floors); Long span floors 60 ft W27x94 27”x 10” @ 6’-8” oc, Short span floors 35 ft W16x40 7”x 16” @ 6’8” oc
W27 6.2 ft * (52) * 60 ft = 19,344 sq ft.
W16 3.83 ft * (46) * 35 ft = 6,166 sq ft.
Total = 25,510 sq ft per floor * 9 floors = ~230,000 sq ft surface area beam framed floors outside core for one Tower [5]

[6] Hat truss framing (floors 107-110 ) ; Use beam framing for one beam framed floor (guesstimate) from [5] = ~ 25,000 sq ft for one Tower

[7] Core cross bracing at all mechanical floors and lobby atrium and miscellaneous steel (plates, angles, channels); (guesstimate) Use [3]core box columns surface area of one floor = 4,880 sq ft * (8) mechanical floors * 50% = ~20,000 sq ft for one Tower.

Totals for [3] - [7]
[3] - 537,000 sq ft
[4] - 968,000 sq ft
[5] - 230,000 sq ft
[6] - 25,000 sq ft
[7] - 20,000 sq ft
Total Unknown primer = ~1,780,000 sq ft * 2 Towers = ~ 3,560,000 sq ft


Summary:

For WTC1,2 for both Towers steel primer surface area
Laclede primer = 6,440,000 sq ft
Tnemec primer = 4,340,000 sf ft
Unknown primer = 3,560,000 sq ft
Total sq ft = 14,340,000 sf
Primer ratios:
Laclede - 45% :Tnemec - 30% : Unknown - 25%



Adjusted ratios based on the following assumptions:
  • No distinction has been made among 3 Tnemec primers.
  • WTC 7 steel primer surface area, propagated dust have not been included.
  • WTC1,2 collapse spalled 80%of Laclede primer from the trusses crushed horizontally. 40% in airborne dust.
  • WTC1,2 collapse spalled 30% of the Tnemec perimeter vertical colums and spandrels from the impact of the floors. The perimeter column assemblies toppled away from the core undamaged until impact with ground. 15% in airborne dust.
  • WTC1,2 collapse spalled 70% of the Unknown primer interior steel framing vertical columns and horizontal floor framing, WF beams and miscellaneous steel. Webs were protected by the flanges. 35% in airborne dust.
Adjusted liberated primers in the airborne dust.

Laclede - [1] 6,440,000 sq ft * 40% = 2,576,000 sq ft in airborne dust.
Tnemec - [2] 4,340,000 sq ft * 15% = 651,000 sq ft in airborne dust
Unknown - [3-7] 3,560,000 sq ft * 35% = 1,246,000 sq ft in airborne dust
Total sq ft of airborne primers = 4,473,000 sq ft.

Primer ratios: rounded up
Laclede - 58% :Tnemec - 15% : Unknown - 28%
 
BasqueArch said:
Estimate of structural steel primer paint areas (in square feet) for WTC1,2
Note: For WTC1,2 - no floors outside the core at 1-6, 8,42,76,109

Laclede primer-[1] primary and bridging floor trusses at tenant floor areas outside the core.
6,440,000 sq.ft. total surface area for Laclede trusses for both towers.

[1] Primary floor trusses per floor; top chord angles (2) 2”x1.5”; bottom chord angles (2) 2”x3”; web 1.09” dia webs center to center 3.33 feet o.c.; truss depth 2.42 feet;
Chords = 34” * 12” = 408 square inches of painted chord surface area per foot of truss + 78 sq inches per running foot of truss for web surface area = 486 square inches / 12”/ 12” = 3.38 square feet of painted chord and web surface area per running foot of truss * 60 feet long span * (2) trusses * (58) pairs of long span trusses = 23,525 sq.ft. of surface area long span trusses per floor.
+ Short span trusses: 3.38 square feet of painted chord and web surface area per running foot of truss * 35 feet long span * (2) trusses * (28) pairs of short span trusses = 6,625 sq.ft. of surface area short span trusses = 30,150 sq.ft. total of surface area primary trusses per floor.

[1] Bridging floor trusses per floor (perpendicular to primary floor trusses) top chord angles (2) 1.5”x1.25”; bottom chord angles (2) 1.5”x 1.25”; web 1.09” dia webs center to center 2.5 feet o.c (estimate).; truss depth 2.0 feet;
Chords = 22” * 12” = 264 square inches of painted chord surface area per foot of truss + 78 sq inches (estimate) per running foot of truss for web surface area = 342 square inches / 12”/ 12” = 2.38 square feet of painted chord and web surface area per running foot of truss * 207 feet long span * (8) trusses = 3,941 sq.ft. long span.

2.38 square feet of painted chord and web surface area per running foot of truss * 87 feet short span * (4) trusses = 828 sq.ft.short span.
3,941 sq ft + 828 sq ft = 4,769 sq.ft. total surface area bridging trusses per floor.

[1] 30,150 sq.ft. + 4,769 sq.ft. = ~35,000 sq.ft.primary and bridging trusses surface area per floor * (110 floors - 8 beam framed mechanical floors - 4 no mechanical floors (double height) - 6 no lobby floors = 92 truss framed floors) = 3,220,000 net sq.ft. trusses surface area per tower * (2) Towers = 6,440,000 sq.ft. total surface area for Laclede trusses for both towers.

Tnemec 99 primer perimeter cols above 9th floor, Tnemec 69,95 4th-9th floors-[2] Perimeter box columns, spandrel plates
4,340,000 sq.ft. perimeter columns and spandrels for both towers.

[2] Perimeter box column; 16” inner x 14” x 14” x 14” other sides. 16” +16” +14” +14”= 60” surface *12 ft. *12 in. / 12” /12” = 60 sq.ft. per column per story - (area covered by spandrel plate 6.5 ft * 1.33 ft = - 8.7 sq.ft.) = 51.3 sq.ft. * 236 columns *110 stories = ~1,332,000 sq.ft. perimeter columns surface area one tower.

[2] Spandrel plate inside surface. 6.5 ft x 3.33 ft = 21.65 sq.ft. per column per floor + outside surface 21.65 sq.ft. - (8.7 sq.ft. column overlap area) = 12.95 sq.ft. = 34.6 sq.ft. inside + outside spandrels per column per story * 236 columns * (110 floors - 6 lobby floors = 104 floors) = ~ 849,000 sq.ft. of spandrels surface area inside and outside one tower.

[2] 1,322,000 sq.ft perimeter columns. + 849,000 sq.ft. spandrels = ~2,170,000 sq.ft. of Tnemec primer perimeter columns and spandrels * 2 Towers = 4,340,000 sq.ft. perimeter columns and spandrels for both towers.


Unknown primer-
[3] Core box columns,
[4] Core wide flange floor framed beams,
[5] Wide flange framed floors outside the core (mechanical floors- 7,8,9,41,42,43,75,76,77,108,109,110,roof) ,
[6] Hat truss framing (floors 107-110),
[7] Core cross bracing at all mechanical floors and lobby atrium and miscellaneous steel (plates, angles, channels)
Total Unknown primer = ~1,780,000 sq ft * 2 Towers = ~ 3,560,000 sq ft

[3] Core box columns; 1.33 ft x 3.0 ft = 8.66 ft perimeter * 12 ft high * (47) columns * 110 stories = ~537,000 sq ft surface area.for one Tower [3]

[4] Core wide flange floor framed beams; W16x40 (guesstimate) 7” x 16”= 3.83 ft ; 3.83ft * (8) * 135 ft = 4,136sq ft + 3.83 ft * (14) * 87 ft = 4,665 sq ft;
Total = ~ 8,800 sq ft total core framed floors * 110 floors = 968,000 sq ft per Tower.[4]

[5] WF framed floors outside the core (Mechanical floors 7,9,41,43,75,77.108,110,roof-9 floors); Long span floors 60 ft W27x94 27”x 10” @ 6’-8” oc, Short span floors 35 ft W16x40 7”x 16” @ 6’8” oc
W27 6.2 ft * (52) * 60 ft = 19,344 sq ft.
W16 3.83 ft * (46) * 35 ft = 6,166 sq ft.
Total = 25,510 sq ft per floor * 9 floors = ~230,000 sq ft surface area beam framed floors outside core for one Tower [5]

[6] Hat truss framing (floors 107-110 ) ; Use beam framing for one beam framed floor (guesstimate) from [5] = ~ 25,000 sq ft for one Tower

[7] Core cross bracing at all mechanical floors and lobby atrium and miscellaneous steel (plates, angles, channels); (guesstimate) Use [3]core box columns surface area of one floor = 4,880 sq ft * (8) mechanical floors * 50% = ~20,000 sq ft for one Tower.

Totals for [3] - [7]
[3] - 537,000 sq ft
[4] - 968,000 sq ft
[5] - 230,000 sq ft
[6] - 25,000 sq ft
[7] - 20,000 sq ft
Total Unknown primer = ~1,780,000 sq ft * 2 Towers = ~ 3,560,000 sq ft


Summary:

For WTC1,2 for both Towers steel primer surface area
Laclede primer = 6,440,000 sq ft
Tnemec primer = 4,340,000 sf ft
Unknown primer = 3,560,000 sq ft
Total sq ft = 14,340,000 sf
Primer ratios:
Laclede - 45% :Tnemec - 30% : Unknown - 25%



Adjusted ratios based on the following assumptions:
  • No distinction has been made among 3 Tnemec primers.
  • WTC 7 steel primer surface area, propagated dust have not been included.
  • WTC1,2 collapse spalled 80%of Laclede primer from the trusses crushed horizontally. 40% in airborne dust.
  • WTC1,2 collapse spalled 30% of the Tnemec perimeter vertical colums and spandrels from the impact of the floors. The perimeter column assemblies toppled away from the core undamaged until impact with ground. 15% in airborne dust.
  • WTC1,2 collapse spalled 70% of the Unknown primer interior steel framing vertical columns and horizontal floor framing, WF beams and miscellaneous steel. Webs were protected by the flanges. 35% in airborne dust.
Adjusted liberated primers in the airborne dust.

Laclede - [1] 6,440,000 sq ft * 40% = 2,576,000 sq ft in airborne dust.
Tnemec - [2] 4,340,000 sq ft * 15% = 651,000 sq ft in airborne dust
Unknown - [3-7] 3,560,000 sq ft * 35% = 1,246,000 sq ft in airborne dust
Total sq ft of airborne primers = 4,473,000 sq ft.

Primer ratios: rounded up
Laclede - 58% :Tnemec - 15% : Unknown - 28%
Click to expand...

Wow - cool! My own estimates per tower were

Floor trusses (LaClede): 300,0002 (3,000,000ft2)
Perimeter (Tnemec): 200,000m2 (2,000,000ft2)
Core (unknown): 50,000m2 (500,000ft2)

The last number was without going into any detail at all about column shapes and dimensions.

You computed 3,220,000 sq ft LaClede and 2,170,000 sq ft Tnemec per tower - both numbers are within 10% of my estimate - pretty cool!
I'll look at your figures for core colums and maybe take yours instead of mine.
[ETA]: Just realized you also are within 10% of my core column surface are (537,000 vs. 500,000), but I ignored core floors and beams, which of course are significant. I also ignored hat truss and mechanical floors. [/ETA]

# oysteinbookmark
 
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BasqueArch said:
Estimate of structural steel primer paint areas (in square feet) for WTC1,2
Note: For WTC1,2 - no floors outside the core at 1-6, 8,42,76,109

Laclede primer-[1] primary and bridging floor trusses at tenant floor areas outside the core.
6,440,000 sq.ft. total surface area for Laclede trusses for both towers.

[1] Primary floor trusses per floor; top chord angles (2) 2”x1.5”; bottom chord angles (2) 2”x3”; web 1.09” dia webs center to center 3.33 feet o.c.; truss depth 2.42 feet;
Chords = 34” * 12” = 408 square inches of painted chord surface area per foot of truss + 78 sq inches per running foot of truss for web surface area = 486 square inches / 12”/ 12” = 3.38 square feet of painted chord and web surface area per running foot of truss * 60 feet long span * (2) trusses * (58) pairs of long span trusses = 23,525 sq.ft. of surface area long span trusses per floor.
+ Short span trusses: 3.38 square feet of painted chord and web surface area per running foot of truss * 35 feet long span * (2) trusses * (28) pairs of short span trusses = 6,625 sq.ft. of surface area short span trusses = 30,150 sq.ft. total of surface area primary trusses per floor.

[1] Bridging floor trusses per floor (perpendicular to primary floor trusses) top chord angles (2) 1.5”x1.25”; bottom chord angles (2) 1.5”x 1.25”; web 1.09” dia webs center to center 2.5 feet o.c (estimate).; truss depth 2.0 feet;
Chords = 22” * 12” = 264 square inches of painted chord surface area per foot of truss + 78 sq inches (estimate) per running foot of truss for web surface area = 342 square inches / 12”/ 12” = 2.38 square feet of painted chord and web surface area per running foot of truss * 207 feet long span * (8) trusses = 3,941 sq.ft. long span.

2.38 square feet of painted chord and web surface area per running foot of truss * 87 feet short span * (4) trusses = 828 sq.ft.short span.
3,941 sq ft + 828 sq ft = 4,769 sq.ft. total surface area bridging trusses per floor.

[1] 30,150 sq.ft. + 4,769 sq.ft. = ~35,000 sq.ft.primary and bridging trusses surface area per floor * (110 floors - 8 beam framed mechanical floors - 4 no mechanical floors (double height) - 6 no lobby floors = 92 truss framed floors) = 3,220,000 net sq.ft. trusses surface area per tower * (2) Towers = 6,440,000 sq.ft. total surface area for Laclede trusses for both towers.

Tnemec 99 primer perimeter cols above 9th floor, Tnemec 69,95 4th-9th floors-[2] Perimeter box columns, spandrel plates
4,340,000 sq.ft. perimeter columns and spandrels for both towers.

[2] Perimeter box column; 16” inner x 14” x 14” x 14” other sides. 16” +16” +14” +14”= 60” surface *12 ft. *12 in. / 12” /12” = 60 sq.ft. per column per story - (area covered by spandrel plate 6.5 ft * 1.33 ft = - 8.7 sq.ft.) = 51.3 sq.ft. * 236 columns *110 stories = ~1,332,000 sq.ft. perimeter columns surface area one tower.

[2] Spandrel plate inside surface. 6.5 ft x 3.33 ft = 21.65 sq.ft. per column per floor + outside surface 21.65 sq.ft. - (8.7 sq.ft. column overlap area) = 12.95 sq.ft. = 34.6 sq.ft. inside + outside spandrels per column per story * 236 columns * (110 floors - 6 lobby floors = 104 floors) = ~ 849,000 sq.ft. of spandrels surface area inside and outside one tower.

[2] 1,322,000 sq.ft perimeter columns. + 849,000 sq.ft. spandrels = ~2,170,000 sq.ft. of Tnemec primer perimeter columns and spandrels * 2 Towers = 4,340,000 sq.ft. perimeter columns and spandrels for both towers.


Unknown primer-
[3] Core box columns,
[4] Core wide flange floor framed beams,
[5] Wide flange framed floors outside the core (mechanical floors- 7,8,9,41,42,43,75,76,77,108,109,110,roof) ,
[6] Hat truss framing (floors 107-110),
[7] Core cross bracing at all mechanical floors and lobby atrium and miscellaneous steel (plates, angles, channels)
Total Unknown primer = ~1,780,000 sq ft * 2 Towers = ~ 3,560,000 sq ft

[3] Core box columns; 1.33 ft x 3.0 ft = 8.66 ft perimeter * 12 ft high * (47) columns * 110 stories = ~537,000 sq ft surface area.for one Tower [3]

[4] Core wide flange floor framed beams; W16x40 (guesstimate) 7” x 16”= 3.83 ft ; 3.83ft * (8) * 135 ft = 4,136sq ft + 3.83 ft * (14) * 87 ft = 4,665 sq ft;
Total = ~ 8,800 sq ft total core framed floors * 110 floors = 968,000 sq ft per Tower.[4]

[5] WF framed floors outside the core (Mechanical floors 7,9,41,43,75,77.108,110,roof-9 floors); Long span floors 60 ft W27x94 27”x 10” @ 6’-8” oc, Short span floors 35 ft W16x40 7”x 16” @ 6’8” oc
W27 6.2 ft * (52) * 60 ft = 19,344 sq ft.
W16 3.83 ft * (46) * 35 ft = 6,166 sq ft.
Total = 25,510 sq ft per floor * 9 floors = ~230,000 sq ft surface area beam framed floors outside core for one Tower [5]

[6] Hat truss framing (floors 107-110 ) ; Use beam framing for one beam framed floor (guesstimate) from [5] = ~ 25,000 sq ft for one Tower

[7] Core cross bracing at all mechanical floors and lobby atrium and miscellaneous steel (plates, angles, channels); (guesstimate) Use [3]core box columns surface area of one floor = 4,880 sq ft * (8) mechanical floors * 50% = ~20,000 sq ft for one Tower.

Totals for [3] - [7]
[3] - 537,000 sq ft
[4] - 968,000 sq ft
[5] - 230,000 sq ft
[6] - 25,000 sq ft
[7] - 20,000 sq ft
Total Unknown primer = ~1,780,000 sq ft * 2 Towers = ~ 3,560,000 sq ft


Summary:

For WTC1,2 for both Towers steel primer surface area
Laclede primer = 6,440,000 sq ft
Tnemec primer = 4,340,000 sf ft
Unknown primer = 3,560,000 sq ft
Total sq ft = 14,340,000 sf
Primer ratios:
Laclede - 45% :Tnemec - 30% : Unknown - 25%



Adjusted ratios based on the following assumptions:
  • No distinction has been made among 3 Tnemec primers.
  • WTC 7 steel primer surface area, propagated dust have not been included.
  • WTC1,2 collapse spalled 80%of Laclede primer from the trusses crushed horizontally. 40% in airborne dust.
  • WTC1,2 collapse spalled 30% of the Tnemec perimeter vertical colums and spandrels from the impact of the floors. The perimeter column assemblies toppled away from the core undamaged until impact with ground. 15% in airborne dust.
  • WTC1,2 collapse spalled 70% of the Unknown primer interior steel framing vertical columns and horizontal floor framing, WF beams and miscellaneous steel. Webs were protected by the flanges. 35% in airborne dust.
Adjusted liberated primers in the airborne dust.

Laclede - [1] 6,440,000 sq ft * 40% = 2,576,000 sq ft in airborne dust.
Tnemec - [2] 4,340,000 sq ft * 15% = 651,000 sq ft in airborne dust
Unknown - [3-7] 3,560,000 sq ft * 35% = 1,246,000 sq ft in airborne dust
Total sq ft of airborne primers = 4,473,000 sq ft.

Primer ratios: rounded up
Laclede - 58% :Tnemec - 15% : Unknown - 28%
Click to expand...

Thanks, BasqueArch:cool: I also tried to calculate surface area of core steel (post No 627) and my figures were lower, but I had not used very realistic model.
Those calculation give us approximate ratios between surface areas of painted steel in Twins, but what about WTC7, which you did not included? Btw, can we expect that the dust from this skyscraper was evenly mixed with that from previously fallen Twins (so as all dust samples from the WTC area should be similar)? Probably not and in some samples WTC7 dust could prevail (?)
 
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Ivan Kminek said:
Thanks, BasqueArch:cool: I also tried to calculate surface area of core steel (post No 627) and my figures were lower, but I had not used very realistic model.
Those calculation give us approximate ratios between surface areas of painted steel in Twins, but what about WTC7, which you did not included? Btw, can we expect that the dust from this skyscraper was evenly mixed with that from previously fallen Twins (so as all dust samples from the WTC area should be similar)? Probably not and in some samples WTC7 dust could prevail (?)
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Hi Ivan.
I didn't get a chance to calculate WTC 7, ran out of time. However, there are some means by which to determine the composition of WTC1,2 dust more accurately.

From this video of the collapse of WTC 7 we can see that the interior of the building collapsed first before the exterior, trapping the generated dust inside until released at the bottom near the end of the collapse.

The dust cloud is smaller than those of the TT, released late, low to the ground and travels across Vessey St, up to the WTC 1 site (to the right), partially blocked by the taller buildings WTC 5,6. The dust is unlikely to have significantly reached south of WTC 2. Firemen’s water and rain reduced the amount of subsequent contamination of this airborne dust south of WTC 2.


Dust samples from south of WTC 2 (Liberty St.) would be the most likely representative of the TTowers, although the partially crushed smaller WTC 3, 4 towers might contribute a minor amount. The farther south of WTC 2 the more likely it is to be representative of the TT dust.
Perhaps Millette has some of these samples analyzed.
 
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chrismohr said:
Either yesterday or today. Jim promised to have his report to me (and everyone) by Wednesday the 29th. I just wrote him asking about the logistics of disseminating this. I'm guessing we'll all just be able to link to the full report (if nothing else I'll figure out how to put it on dropbox!)
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Just to document this here...
 
moorea34 said:
So.... Today :)
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Are we almost there yet? Yes! Millette said it'll be done today and I have time to get the posting etc done. It'll be on a new thread. I can hardly wait either. He did tell me the conference went well and the WTC dust presentation was well received. "It is currently in internal quality review" (Millette's words) as of Tuesday evening.
 
Very good! I will make good on my promise to create a youtube video on this subject once the results are in.
 
Thanks a lot, Chris:o)

Btw, I (of course) read your thread and I tried to contribute there, but even after more than one hour, my post has not appear there. Perhaps because USA moderators are sleeping now? Frankly, I don't like it, with such time delays, the discussion would not be really vivid and coherent:(
 
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...before I'm allowed to contribute in the "Jim Millette study thread", two remarks here.

Oystein: you answered question:

3) However, Red/Gray Chips Could Be Laclede Primer Paint?

in this way:

3) Probably false: Millette found no strontium chromate, but found some titanium (dioxide, I presume). Both these facts would indicate that his chips are not the LaClede formulation.

Of course, you can be right. But I am asking another question:
Can titanium dioxide be present in small amounts in kaolin/kaolinite?

And my quick answer is yes:cool: Look here or here.

And, strontium chromate in mere 1 wt% concentration in Laclede paint might not be detected. Everything else we know from the preliminary results is consistent with Laclede paint, and therefore I'm still very optimistic:cool:

Concerning epoxy binder, Jim just confirmed what I have claimed from the very beginning: crosslinked epoxy binder can't be dissolved in any solvent and it can only be "softened" or swollen (typical behavior)
 
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