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Dial 9/11 for Evidence

World Trade Center Building 7

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The World Trade Center

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The World Trade Center

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FEMA: WTC 1 & 2 Debris

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FEMA: South Tower Debris

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FEMA: North Tower Debris

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WTC7: before noon

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WTC7: west side

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WTC7 final damage

Pedestrian bridge, south side

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WTC7 final damage

1st floor, southeast

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WTC7 final damage

Lobby, 1st floor (note atrium)

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WTC7 final damage

Lobby, 3rd floor

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WTC7 final damage

NIST schematic: south face 1-19

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FEMA: Building 7 Debris

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Building 7 Debris: 9/23

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FEMA: Building 7 Debris

W

S

E

N

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FEMA: Building 7 DebrisE

W

SN

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Ground Zero Debris

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Larry’s New Toys

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NIST: WTC7 Structure

Basic framing layout: floors 8-20, 24-45

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NIST: WTC7 Structure

Columns and framing

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FEMA: WTC7 Structure

5th floor: 14” concrete w/embedded steel T-sections

7th floor, same, 8” concrete

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FEMA: WTC7 Structure

Trusses: floors 5-7(transfer weight from upper columns to foundation columns)

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FEMA: WTC7 Structure

Weight transfer trusses & girders (floors 5-7)

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NIST: Collapse Mechanism

Thermal expansion of floor beams against girder

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NIST: Collapse Mechanism

Column 79 girder connection

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NIST: Collapse Mechanism

Column 79

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NIST: Collapse Mechanism

Columns 80 & 81

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NIST: Collapse Mechanism

Unsupported east floors fall on Truss 2

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NIST: Collapse Mechanism

Truss 2 fails

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NIST: Collapse Mechanism

Columns 77-78-78A buckle

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NIST: Collapse Mechanism

Core column collapse progression

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NIST: Collapse Mechanism

Damage to south face, from south

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NIST: Collapse Mechanism

Damage to south face, from west

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WTC7 Structure

Multiple-floor atrium

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NIST: Collapse Mechanism

Global collapse: part 1

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NIST: Collapse Mechanism

Global collapse: part 2

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NIST: Collapse Mechanism

Time comparison: model vs. observed

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NIST: Free Fall NOT

Roof-center pixel change

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NIST: Free Fall NOT

Roof-center fall distance

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NIST: Free Fall NOT

Roof center fall velocity

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NIST: Fuel Fires NOT

• Heat would have stopped the generators that powered the fuel pumps

• Fire couldn’t have been hot/long enough to raise the concrete/steel temps to point of strength loss

• Would have generated visible smoke through lourves, none was observed

• Emergency generator “day” tanks on 5,7,9 floors– wouldn’t have added much to combustible load– safety measures in place would have prevented reloading– weren’t near probable collapse initiation points

Fuel line rupture couldn’t create the problem:

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NIST: Fire Observations

Diagrams based on photos (starting ch 5.6.5, vol 1, p. “290”)

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WTC7 Steel

• Only one piece examined by FEMA (App C)– liquid iron/oxygen/sulfur eutectic moved along

intergranular boundaries, weakening the beam– eutectic mixture evidenced only 1000C, much

lower than expected for melting steel

• Possibilities raised by FEMA– long-term heating in the ground– pre-collapse, accelerated steel weakening

• Not examined further by NIST• Raises the larger question of WTC steel

removal

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Removal of WTC SteelNot all bite-sized pieces

Indicates not total dismemberment, but confuses issue of what melted prior to collapse

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Removal of WTC SteelWhy is it an important issue?

• Largest crime in U.S. history

• Law requires preservation of evidence

• 350,000 tons removed (acc. to FEMA)

• Bloomberg: looking at steel doesn’t tell anything, need computer models

• Yet said to be “highly sensitive”

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Removal of WTC SteelReasons given

• WTC1-2: Needed to find survivors• WTC7– Needed to find survivors (but evacuated)– Putting pressure on Verizon building (but

could have just moved that)

• In any case, could have labeled, docu-mented location, and saved elsewhere

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Removal of WTC SteelWhat happened to it?

• Thousands of pieces trucked to 4 landfills• Immediate result:– Most sent to Asia– Some used to build warship U.S.S. New York– 150 pieces saved (in off-limits hangar at JFK)

• Only parts from underground and lobby area• Who decided?

• Later (January 2007) found more– 2 columns, 3 connected perim columns

(under road excavated for human remains)– 1 burned column at edge of site (city: cutoff)

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Removal of WTC SteelWhat did FEMA look for?

• Exterior column trees & interior core columns from 1 & 2 above the impact zone or exposed to fire and/or aircraft-impacted

• Badly burnt pieces from WTC 7.• Connections from WTC 1, 2, and 7, such as seat connections,

single shear plates, and column splices.• Bolts from WTC 1, 2, and 7 that were exposed to fire, fractured,

and/or that appeared undamaged.• Floor trusses, including stiffeners, seats, other components.• Any piece that, in the engineer's professional opinion, might be

useful for evaluation. When there was any doubt about a particular piece, the piece was kept while more information was gathered. A conservative approach was taken to avoid having important pieces processed in salvage yard operations.

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Removal of WTC SteelWhat about FEMA?

• 62 trips to landfills Oct-Feb

• No access to Ground Zero

• No permission to collect or store steel

• No subpoena power to obtain building plans (to make intelligent choices)

• Their observation of anomalies dropped

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Removal of WTC Steel“Highly sensitive”

• Nov 26: Trucks monitored by GPShttp://securitysolutions.com/ar/security_gps_job_massive/

– Sept: criminal scheme to divert steel– Oct: found 250 tons of scrap in LI and NJ– “Geofenced” zones, “geofenced” corridors– Improved efficiency and gridlock

• Driver behavior monitored, checked, analyzed (1.5hr lunch -> firing)

• “Loads consisted of highly sensitive material”