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1
Destructionof the Twin Towers
2
The Event
3
The Event
AA-11 & UA175 Flight Paths
Alleged flight paths (lost to radar for part of trip)
4
The Event
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The Event
AA-11 Impact on WTC-1
One landing gear
6
The Event
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The Event
UA-175 Impact on WTC-2
Landing gear, engine, fuselage section
8
The Stage
9
World Trade Center
The Buildings: Layout
North Tower
South Tower
Building 7
N
10
World Trade Center
The Buildings: Heights
N
110 stories
47 stories
11
WTC 1-2 Construction
47 central core columns, 244 perimeter columns
Columns
12
WTC 1-2 Construction
Basement, first 10 floors of WTC1
in Progress
13
WTC 1-2 Construction
14”x36” near bottom, various smaller forms near top
47 Central Core Columns
14
WTC 1-2 Construction
3-column-3-floor assemblies alternating across 3 floors, connected by welded/bolted spandrel plates
244 Perimeter Columns
Truss mounting
points
Diagonal- brace
mounting points
15
WTC 1-2 Destruction Features
Perimeter cross-link strength
Acting like a Roman arch over the hole
16
WTC 1-2 ConstructionFloor Support Trusses
17
WTC 1-2 Construction
Perimeter column
Floor Support Trusses
Core column
Main trusses: these were double
loops stick up into grooves on metal deck, act as shear studs
18
WTC 1-2 Construction
Floor Support Trusses
Transverse truss: at right angles to main trusses
19
WTC 1-2 Construction
“Hat” Truss
Floors 106-110:
Helps spread stress forces within core and between
core and perimeter, and supports
communications tower on top
20
The Reports
21
The Reports
• FEMA -- 2002
• 9/11 Commission -- 2004
• NIST: National Institute of Science and Technology -- 2005
22
FEMA Investigation/Report• Carried out by “volunteers” from the American Society of Civil
Engineers• Bush administration agency (Katrina)• Headed by man who headed Okla.City bombing study• No “authority to impound pieces of steel before they were
recycled”• No subpoena powers -- couldn’t get blueprints• “The ‘official investigation’ blessed by FEMA ... is a half-baked
farce that may already have been commandeered by political forces whose primary interests, to put it mildly, lie far afield of full disclosure” -- Fire Engineering Magazine
• Basic theory: Impact and fire caused a “pancake” collapse
• Report+comment: http://911research.wtc7.net/wtc/official/fema.html
23
Conclusion: Pancaking
FEMA Investigation/Report
(PBS)
24
• Chairmen: "fullest possible account of the events surrounding 9/11.”
• Provided intensely detailed description of situation in buildings and actions of emergency personnel
• Mentioned that the buildings collapsed (period)
9/11 Commission Report
25
NIST Report
26
Problems with NIST Report• Institutional -- NIST was politicized• Coverage -- Only covered what they claim
happened up until the beginning of “collapse;” virtually no analysis of what “inevitably” then happened -- wasn’t part of their assignment
• Evidence -- Used questionable computer model, used little (and ignored) real evidence
• Reality -- the “collapse” displayed too many features inconsistent with a gravity-driven model.
27
NIST Problems:
Institutional
NIST had become “fully hijacked from the scientific into the political realm...scientists lost scientific independence and became little more than ‘hired guns.’...By 2001, everyone in NIST leadership had been trained to pay close heed to political pressures... Everything that came from the hired guns was by then routinely filtered through the front office and assessed for political implications before being released,” and was also scrutinized by the NSA, OMB, and the Commerce Department headquarters. -- whistleblower (former NIST employee)
28
So, what did NIST say?
29
NIST’s approach
A Computer Model(ignored much physical evidence)
30
NIST: Computer model approach
• Set up three scenarios with assumptions representing different degrees of damage
• See which one creates collapse• If none do, tweak the worst one further
and divorce it further from empirical evidence by denigrating that evidence.
• Example: South damage range was 3-10 damaged columns, only using 10 did job
31
NIST: Computer model approach• "Upon a preliminary examination of the
middle case, it became clear that the towers would likely remain standing...[so] the most severe case ... was used for the global analysis of each tower.” -- NIST Final Report
• "To the extent the [severe-case] simulations deviated from the photographic evidence or eyewitness reports, the investigators adjusted the input.” -- NIST
32
• "[A] fundamental problem with using computer simulation is the overwhelming temptation to manipulate the input data until one achieves the desired results. Thus what appears to be a conclusion is actually a premise... NIST tweaked the input and the buildings feel down” -- architect Eric Douglas
NIST: Computer model approach
33
NIST’s sequence• Plane impact
– Severed some core columns– Removed fireproofing from most core columns and much of
floor-supporting trusses
• Fires created tremendous heat– weakened core columns– Caused floor trusses to weaken and sag, pulling in the
perimeter columns, reducing peripheral support
• Global collapse commenced– Top of tower above damage acted as pile driver– Floors below couldn’t resist– Out of thousands of pages, they only devoted a paragraph
to this, with no indication of analysis of the process
34
NIST: Severed Core Columns
• North: 6 severed, South: 10 -- but:– North hit higher, where columns weaker– Only engines capable of such damage,
but North hit head on, South off to side, so should have been other way around
• There is no actual visual record– All NIST has is a computer model– Only 256 pieces of steel out of thousands
saved
35
NIST: About that steel...
• NIST, 2003: "adequate for purposes of the Investigation. Regions of impact and fire damage were emphasized in the selection of steel for the Investigation.”andsteel analysis "includes...estimating the maximum temperature reached by available steel."
BUT• NIST, 2005: Steel is merely “sufficient for
determining quality and mechanical properties”
36
• Fire retardant coating good for 2 hours• So have to assume massive dislodging of
fire retardant by impact.• NIST: of 47 core columns, FR dislodged on
43 in North, 39 in South. How know?• No evidence, just 15 shotgun blasts at flat
plates (not beams) in a plywood box.
NIST: Fire weakens steel
Fire Retardant
37
• Building is an interconnected grid of thousands of tons of steel
• Steel conducts heat (though not ideal)• Therefore, building sucks heat away from any
place that has heat locally applied to it• Therefore, it takes a LONG time before steel
temperature reaches local air temperature.• But jet fuel was consumed within 15 minutes, and
office fires tend to burn out in any one area after about 20 minutes.
NIST: Fire weakens steel
Temperature Behavior
38
• Model: 1000°C only 15-20 mins in any one place, otherwise 500°C
• NIST: physical evidence indicates max temp of any steel (not necessarily columns) was 600°C
• NIST: examination of perimeter steel indicated max was 250°C
• Core had less oxygen than perimeter, so likely not as hot, and no evidence that it actually did get that hot
• Structural steel begins to soften at 425°C• Kinda problematic for a claim of weakened columns
NIST: Fire weakens steel
Temperature claims
39
• Basic idea (I’ve seen two quoted)– Sagging pulls in the
perimeter columns– Sagging doesn’t
pull in the perimeter columns, but when they cool and contract, that happens
• Were they trusses or girders?
NIST: Fire weakens steelFloor trusses sag
http://911review.org/Wget/www.nerdcities.com/guardian/wtc/they-lied-about-trusses.htm
40
NIST: Fire weakens steelFloor trusses sag
41
• (Creep note: happens at ~30% of melting point, in this case ~920°C, so shouldn’t have happened)
• Sag per model: w/creep: 44”, w/out creep: 24”• Problem: NIST paid UL $250K to test truss
behavior, max deflection was 4”• NIST: UL tests weren’t representative, all had
fireproofing• Actually, all had LESS fireproofing than build specs• This is a complex issue, and I’ve seen a lot of
different takes on it.
NIST: Fire weakens steelFloor trusses sag
42
NIST: Fire weakens
steel
Sagging trusses pull wall inward
43
NIST: Fire weakens steel
Sagging trusses pull wall inward
44
Non-NIST Observation
Sagging floors?
Trouble is, the floors at the perimeter walls could not have sagged if the trusses were able to pull in the
walls.
45
Let’s get technical !
1. for NIST’s “pile driver” to cause collapse?
2. to expand the large, fast dust clouds?
3. to throw heavy beams fast and far?
Was there ENOUGH ENERGY available from a GRAVITY DRIVEN collapse
46
Mind-numbing analytical details and calculations moved to the end of the presentation, where they may never be seen again . . .
Let’s get technical !
47
So we got technical !
1. NIST’s “pile driver” theory of collapse
2. expansion of the large, fast dust clouds
3. Heavy columns thrown far and fast
And guess what?There was not ENOUGH ENERGY available
for any of these theories or observations:
48
If gravity didn’t have what it takes,
What did?
49
TheAlternative
Theory
50
The Alternative Theory:
Definition
Controlled Demolition
the bringing down of a building by the use of explosives/incendiaries to simultaneously remove critical supporting structure
51
The Alternative Theory:
Immediate Objections
• How on earth could “they” have moved enough explosives into those towers without being detected
• Too many people -- someone would have told
• The government might do some bad things, but it would never commit that heinous a crime
52
The Alternative Theory:
Primary Response
A demonstrated fact should not be ignored or denied simply because there is no immediate explanation of its history (e.g., Jupiter’s moon Titan has methane in its atmosphere; we can demonstrate this, though we have no idea how it got there)
53
The Alternative Theory:Calling a Spade a Spade (WTC7)
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Danny Jowenko, a Danish demolition expert not dependent on U.S. reputation and government contracts
54
55
The Alternative Theory:Features Consistent with Explosives,
Inconsistent with Fire1. Fall
A. Rapid onset of destruction at jet impact point
B. Straight-down symmetrical collapse
C. Near-freefall acceleration through path of greatest resistance
D. Large proportion of debris outside footprint
2. Explosives/incendiariesA. Dismemberment of steel framework
B. Lateral ejection of steel members up to 600’
C. Pyroclastic (suspension) clouds of pulverized concrete
D. Evidence of high temperatures (molten metal, iron microspheres
E. Chemical evidence of thermitic material
56
WTC 1-2 Destruction Features
57
WTC 1-2 Destruction Features
Sudden onset of destruction at point of impact
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WTC 1
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WTC 1-2 Destruction Features
Sudden onset of destruction at point of impact
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WTC 1-2 Destruction Features
Straight-down Symmetrical Collapse
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WTC 1-2 Destruction Features
Straight-down (almost) Symmetrical Collapse
WTC 2 (slow)
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WTC 1-2 Destruction Features
• Many different versions– some (even 9/11 Commission) claiming 10 secs– Jim Hoffman’s video timeline indicates 15 secs
http://911research.wtc7.net/wtc/evidence/timeline/videos.html
• Even 15 too fast for overcoming obstacles at each story:– destruction of the structural integrity– pulverization of the concrete in the floor slabs, and other non-metallic
objects– acceleration of the remains outward or downward.
Time of Descent
62
WTC 1-2 Destruction Features
Near-Freefall Acceleration
WTC 1QuickTime™ and aMotion JPEG A decompressor
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The Alternative Theory:
FEMA report: WTC1-2 Debris
Debris Outside Footprint
Heavy debris,perimeter columns
Lighter debris
X Perimeter columns outside debris radius
64
WTC 1-2 Destruction Features
Dismemberment: Debris Pile
65
WTC 1-2 Destruction Features
Dismemberment: Debris Pile
66
WTC 1-2 Destruction Features Debris
• Bone Fragments– 2006: 750 found on roof of Deutsche Bank
(250’ from WTC 1&2), each less than 1/2” long– 2010: 72 found in 2 dump trucks of debris
being sifted by forensics experts– 2012: reports of some still being found
• Victims (as of May 2002)
– 2823 victims– 289 whole bodies recovered as of May 2002– 1053 individuals identified
67
WTC 1-2 Destruction Features
Dismemberment: Core Obliteration
Massive 1000’ structure of cross-braced thick steel columns were dismembered (North tower section survived only temporarily)
68
WTC 1-2 Destruction Features
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Dismemberment: Core Obliteration
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WTC 1-2 Destruction Features
Large pieces of the structures thrown horizontally long distances at high velocities (40-60 mph)
LateralEjection
perimeter column sticking out of the corner of WTC 3
70
WTC 1-2 Destruction Features
• “Pyroclastic” is used to describe volcanic dust clouds– Fine particles (solids suspended in air)– Hot inside– Heat drives rapid expansion– Little mixing with ambient air
Pyroclastic Dust Clouds
71
WTC 1-2 Destruction Features
Concrete was pulverized before it hit the ground, as destruction progressed.
Pyroclastic Dust Clouds
Note also the dust’s explosive mushrooming upward and outward (many times the size of the tower)
72
WTC 1-2 Destruction Features
* Fine dust suspended* Rapid expansion* Little mixing with air
Pyroclastic Dust Clouds
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WTC 1-2 Destruction Features
Dust reached ground 10 seconds after start
Core “spire” still standing here, fell at 29 seconds
Cloud has reached out 700’
Speed: 700/19 = 37 feet/sec = 25 mph
Pyroclastic Dust Clouds
74
WTC 1-2 Destruction Features
Dust reached ground 10 seconds after start
Core “spire” still standing here, fell at 29 seconds
Cloud has reached out 700’
Speed: 700/19 = 37 feet/sec = 25 mph
Expanding Dust Clouds
75
WTC 1-2 Destruction Features
Damage line remains in place for a while while roof-top starts to descend, appears to disintegrate before the “collapse” begins.
Destruction Above Impact Zone: WTC1
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WTC 1-2 Destruction Features
Equal-time frames, angle changes from 1 to 2, not from 2 to 3, cessation of rotation violates conservation of angular momentum, unless mass is being destroyed
Destruction Above Impact Zone: WTC2
77
WTC 1-2 Destruction Features
Dust and debris are ejected before fall -- South tower top is only tipping
Early ejections
78
WTC 1-2 Destruction Features
Ejections of dust far below destruction -- pressure might be distributed that far down due to pile-driver compression, but where does the dust come from, and why only in specific places?
Squibs
79
Explosions: Witness Reports
In NYFD oral histories, hidden by NYFD until NY Times forced release in 2005, about 120 out of 500 reported explosions
WTC 1-2 Destruction Features
80
Explosions: Witness Reports
Firemen and WTC1-2 explosions
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WTC 1-2 Destruction Features
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Explosions: Witness Reports
Firemen hearing it; post-WTC1-2 explosions
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WTC 1-2 Destruction Features
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High Temperatures
• Remember:– Office fires: Usually max 1100°F– Iron/steel melt at about 2800°F
• Metallic microspheres– Metal sprayed into air so surface
tension can pull into near-spherical shapes
– Iron (2800°F), lead (3180°F),molybdenum (4500°F)
• Vaporized steel
WTC 1-2 Destruction Features
83
High Temperatures
NASA heat image from several weeks after 9/11 -- temperatures in excess of 1000°F on the surface
WTC 1-2 Destruction Features
84
Iron-rich MicrospheresWTC 1-2 Destruction Features
85
Iron-rich Microspheres
• RJ Lee (2003, 2004)– Studied Deutsche Bank dust contamination– Iron particles: 6% of WTC dust (>> .04%)– Lead oxide coated -> vaporization (3180°F)
• US Geological Survey (2005)– WTC Particle Atlas– Iron-rich spherules
• NIST mentions neither
WTC 1-2 Destruction Features
86
Vaporization of Steel• FEMA Report, Appendix C (WTC7) authors
– 1” column -> 1/2”, razor sharp, gaping holes like swiss cheese
– “partly evaporated at extremely high temps– Thinning due to high temp (1800F) corrosion– Eutectic mixture w/sulfur (lowers melting point)
accelerates intergranular melting
• NIST ignored this– In Q&A, claimed sulfur came from wallboard– Never experimented, doesn’t happen
WTC 1-2 Destruction Features Vaporization of Steel
87
WTC 1-2 Destruction Features Vaporization of Steel
From FEMA Report, Appendix C (WTC7)
88
• Question:What could generate sufficient heat to melt steel?
• Answer:– Thermite -- an incendiary mixture of iron oxide
(rust) and aluminum OR– Thermate -- the above combined with sulfur
(lowers the melting point of iron/steel and would help explain the FEMA report’s sulfidation
• BUT . . .
WTC 1-2 Destruction Features Residues
89
WTC 1-2 Destruction Features Residues
• Objection:– Many: Thermite can’t cut through beams– NIST: Thermite can cut through a beam, but takes
a while, so it isn’t fast enough to explain the rapid collapses.
• Answer: – In fact, existing patented technology addressed
this and other NIST objections, OR – Nanothermite -- thermite composed of particles
on a nanometer (4 ten-millionths of an inch) scale.
• BUT . . .
90
WTC 1-2 Destruction Features Residues
• Objection:Forget about nanothermite. All the devices for directing the thermite blast would be found in the wreckage
• Answer: – Nothing was found in the wreckage of that sort
-- no desks, cabinets, furniture -- just concrete powder and structural steel
– But in any case, self-destructing devices DO exist...
91
WTC 1-2 Destruction Features Residues
92
WTC 1-2 Destruction Features Residues
• Objection:Well, there'd at least be miles of wiring tangled up in the debris.
• Answer:Actually, wireless detonators were even available that can be connected to a programmed set of detonation instructions -- leaving open the possibility of an instantly reprogrammable set of instructions to match any given situation, such as
where a plane hits. . .
93
WTC 1-2 Destruction Features Residues
94
WTC 1-2 Destruction Features Residues
• Objection:I still don't believe thermite is fast enough, and even if it were, you'd need TONS of it.
• Answer:That's why I suggested nanothermite.
95
WTC 1-2 Destruction Features Residues
• Objection: There’s no such thing (in many forms!)• Answer:
“At Livermore Laboratory, sol-gel chemistry [hydrocarbon matrix] ... has been the key to creating energetic materials with improved, exceptional, or entirely new properties ... These new materials have structures that can be controlled on the nanometer (billionth-of-a-meter) scale ... In general, the smaller the size of the materials being combined, the better the properties of energetic materials. Since these ‘nanostructures’ are formed with particles on the nanometer scale, the performance can be improved over materials with particles the size of grains of sand or of powdered sugar. In addition, these ‘nanocomposite’ materials can be easier and much safer to make than those made with traditional methods.”-- “Nanoscale chemistry yields better explosives”, in Science and Technology Review, October, 2000, published by Lawrence Livermore Lab
96
WTC 1-2 Destruction Features Residues
from Lawrence Livermore Lab: “Nanoscale chemistry yields better explosives”
97
WTC 1-2 Destruction Features Residues
• Objection:What does that article have to do with WTC?
• Answer:– Physicist Steven Jones found metallic chips in the WTC
dust: red on one side, gray on the other– Their amount was not insignificant– The red side consisted of nano-scale particles and flat
platelets, and contains, among other things, aluminum, iron, and oxygen, in a carbon-containing matrix
– When heated to ~420°C, there was a sudden release of heat and production of iron-rich microspheres
– The analysis team pubished a paper on this in 2009
• BUT . . .
98
WTC 1-2 Destruction Features Residues
Red-gray (nanothermite?) chips
99
WTC 1-2 Destruction Features Residues
Nanothermite particles?
100
WTC 1-2 Destruction Features Residues
• Objection:– The red layer was obviously protective paint coating
(there are persuasive chemical analysis arguments to this effect)
– They should have heated it in the absence of air -- thermite has its own oxygen and paint doesn’t
• Answer:– Paint doesn’t have nano-scale particles– Paint does not burn hot enough to create iron-rich
spheres– Nils Harritt stated on the record that they obtained
samples of WTC protective paint and the chemical signature was not the same.
101
Conclusion
• We know the official story is not true(this is only the tip of the iceberg)
• We can surmise, but don’t know, what happened• The 9/11 Commission was compromised
– Wrong goal: how did the attacks succeed– Staff head Philip Zelikow NOT independent
• We need a new, truly independent investigation with subpoena power– NYCCAN attempting to get a NYC investigations
102
103
Appendix 1:
WTC Steel Removal
104
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
• FEMA calls for further investigation, NIST doesn’t do it• Raises the larger question of WTC steel removal
105
Removal of WTC SteelNot all bite-sized pieces
Indicates not total dismemberment, but confuses issue of what melted prior to collapse
106
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”
107
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 part)
• In any case, could have labeled, docu-mented location, and saved elsewhere
108
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 perimeter columns
(under road excavated for human remains)– 1 burned column at edge of site (city: was cut off)
109
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.
110
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
111
Removal of WTC Steel“Highly sensitive”
• Nov 26: Trucks monitored by GPShttp://securitysolutions.com/ar/security_gps_job_massive/
– Sept: alleged 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”
112
Appendix 2:
Energy:A Technical Discussion
113
Let’s get technical !
1. for NIST’s “pile driver” to cause collapse?
2. to expand the large, fast dust clouds?
3. to throw heavy beams fast and far?
Was there ENOUGH ENERGY available
114
Forces and Momentum
Momentum Transfer Analysis of the Collapse of the Upper Storeys of WTC 1
Dr. Gordon Ross, June 2006http://www.journalof911studies.com/articles/Journal_5_PTransferRoss.pdf
115
Forces and Momentum
Previous momentum analyses treated floors as individual items hanging in space, instead of being interconnected, with forces moving and distributing through the structure below.
Basic idea
116
Forces and Momentum
1. Elastic phase -- load increases to failure load, at which point column is shortened 0.2% of its length; can recover (“bounce”)
2. Shortening phase -- failure load then shortens column, up to 3% of its length
3. Buckling phase -- buckling points appear, much less force needed to continue
4. Pressure wave -- moves at 4500 m/sec
Compression of Steel ColumnsWhat you need to know about . . .
117
Forces and Momentum
• Top 16 stories of North Tower (as a chunk) free-falls through a “disappeared” story
• Hits at 8.5 m/sec• At that speed, it takes .013 sec to shorten
next story by 3% (to commence buckling)• .013 sec is time for force to propagate
~60m, or 16 stories down, so all these are “moving” and thus have momentum
What happens 1
118
Forces and (conserved) Momentum
• Now 16+1 stories falling, cuts speed from 8.5 to 8 m/sec . . . BUT
• The 16 stories below are also moving slightly, and their combined momentum slows the top chunk to about 5 m/sec
• This gives additional time for the propagation wave to involve additional floors
What happens 2
119
Forces and Momentum
... and after many detailed calculations of kinetic and potential energy, elastic and plastic strain energy, and concrete pulverization energy...
120
Forces and Momentum
Energy Summary
121
Forces and Momentum
• Initial drop -- Assumption of unimpeded drop is unrealistically favorable to continued collapse
• Elastic springback -- robs some kinetic energy• Ejections -- mass is lost by material thrown
outside the tower perimeter, and energy required to move that mass outward
• The “chunk” -- energy also absorbed by damage sustained by lighter columns in “chunk”
• Other damage -- energy needed to sever floor/column connections and destroy other structural elements and floor contents
But that’s an underestimate
122
Forces and Momentum
The energy balance of the collapse moves into deficit during the plastic shortening phase of the first impacted columns showing that there would be insufficient energy available from the released potential energy of the upper section to satisfy all of the energy demands of the collision. The analysis shows that despite the assumptions made in favor of collapse continuation, vertical movement of the falling section would be arrested prior to completion of the 3% shortening phase of the impacted columns, and within 0.02 seconds after impact.
Conclusion
i.e., Collapse stops after 1 floor drop
123
2. Dust Cloud Expansion
The North Tower's Dust Cloud:
Analysis of Energy Requirements for the Expansion of the Dust Cloud Following the
Collapse of 1 World Trade Center
Jim Hoffman, January 2004 (v. 3.1)http://911research.wtc7.net/papers/dustvolume/volumev3_1.html
124
Dust Cloud Expansion
But before we get into the expansion of the dust cloud,
what about all that dust?
125
Dust Cloud Expansion
• Concrete in tower: 90,000 tons• Pulverize concrete to ~2mm size: 1.5KWh/ton
http://www.b-i-m.de/public/ibac/mueller.htm
• Energy to pulverize to 2mm: 135,000 KWh• But energy to pulverize inversely proportional to sqrt
of particle diameter, dust 0.06 mm (or less)http://www.911-strike.com/powder.htm
• Sqrt 2 = 1.4, sqrt .06 = .24 --- factor of 6• So dust creation requires ~ 6x135,000=800,000 Kwh
Pulverization Energy
126
Dust Cloud Expansion
• Somewhere between 135,000 and 800,000 KWh needed
• FEMA’s report: Tower 1 construction stored more than 111,000 KWh potential energy
• So not enough energy to pulverize concrete not as fine as observed, much less distribute it in fast-moving large clouds
• But forget that. There’s more ....
Pulverization Energy
127
Dust Cloud Expansion
The amount of thermal energy needed to expand the North Tower dust cloud as observed 30 seconds after collapse is far greater than the gravitational potential energy available from the height and mass of the tower. How?
Basic idea
128
Dust Cloud Expansion
1. expansion of gases due to heat
2. vaporization of liquids and solids3. chemical reactions resulting in a
net increase in the number of gaseous phase molecules(since this last can only be due to explosives, we’ll ignore it)
What can produce expansion?
129
Dust Cloud Expansion
1. Estimate cloud volume at given specific time before diffusion occurs
2. Factor out mixed-in air to get volume of particles of the contents originally in tower
3. Establish ratio of this to the original volume -- i.e., the volume of the tower?
4. How much energy is needed to generate that ratio of expansion for different levels of gas-expansion and liquid/solid vaporization?
Analysis steps
130
Dust Cloud ExpansionThe picture (30 seconds later) The ref points
The cylinder:Height: 200’Radius: 800’
131
Dust Cloud Expansion
• Cylinder volume: 402 million ft3
– ~1/4 is buildings, so dust = 300 million ft3 – assume 1/3 is mixed-in air (unlikely -- see
next slide) so conservative estimate ofCloud Volume = 200 million ft3
• Speed of advance observed: 25 mph
Parameters at 30 sec
132
Dust Cloud Expansion
• 25 mph is too fast for advance to be diffusion• Outside features of cloud were relatively
stable, not diffused by m/d• Sinking sections replaced by clear air• Reports of people being picked up and
carried by “solid” wall of hot dust
Due to mixing/diffusion?
133
Dust Cloud Expansion
• Tower volume:1368’ x 207’ x 207’ = 58.6 million ft3
• Cloud volume: ~200 million ft3
• Expansion ratio: 3.41 (conservative)
Expansion in 30 sec
134
Dust Cloud Expansion
• If pressure and amount (mass) stay the same, volume is proportional to absolute temperature (PV = nRT)
• If start temp was room temp (300oK), 3.4 x that is 1020oK, an increase of 680o.
• Raising air that far requires 499,500 KWh (remember: available energy = 111,000)
• But it gets worse . . .
1. Gas expansion by heat 1
135
Dust Cloud Expansion
• Such tiny dust particles (10-60 microns) will reach temp equilibrium with surrounding air very fast
• So you have to raise them 680o too• The 90,000 tons of concrete dust would
require > 11 million KWh• And if there’s water, it gets worse, but
we’ll skip that and treat water separately
1. Gas expansion by heat 2
136
Dust Cloud Expansion
• 3.4 expansion means 2.4 x tower volume would be created steam: 2.4 x 58 million ft3 = 141 million ft3 = 4 billion liters
• Volume at 100oC: steam = 1680 x water• So 2.4 million liters of water needed to
produce the entire cloud volume of steam• Conversion would require > 1.5 million KWh• Plumbing + concrete + people: not enough
2. Vaporization of water
137
Dust Cloud Expansion
• Heating of gases: would require 780oC– Ground level not that hot– High heat apparent higher in cloud (next slide)
• Water-to-steam: requires too much water, needs additional heat to get to 100oC first
• If combined: steam conversion would add to the energy requirement of gas heating, additional head needed for concrete dust
• Reduction? Early dust settling would reduce needed heat, but cloud behavior contradicts that
How much of which?
138
Dust Cloud Expansion
“Digital photographs and videos show a bright afterglow with a locus near the center of the cloud, commencing around 17 seconds after the onset of the North Tower's collapse.
“Once the afterglow started, the cloud developed large upwelling columns towering to over 600 feet, and the previously gray cloud appeared to glow with a reddish hue.”
High Temperatures
139
Dust Cloud Expansion
Conservative figures
Summary: Energy Sources and Requirements
140
Dust Cloud Expansion
• They are based on an estimate of dust cloud volume at a time long before the cloud stopped growing.
• They use a liberal estimate of the contribution of mixing to the volume (1/3).
• They ignore thermal losses due to radiation.• They ignore the resistance to expansion due to the inertia
of the suspended materials, and energy requirements to overcome it.
Why conservative?
141
Dust Cloud Expansion
Conclusion
The massive discrepancy between the gravitational energy available and the heat energy needed to drive the expansion of the dust cloud render the gravity explanation for the collapse of the North Tower (and similarly, the South Tower) untenable.
142
3. Beam Ejection
143
Beam Ejection
http://www.photolibrary.fema.gov/photodata/original/3942.jpgPhotograph by Michael Rieger taken on 09/18/2001 in New York
144
Beam EjectionStructure of Perimeter Columns
(FEMA)
145
Beam EjectionWell, maybe not 600,000 lbs...
NIST, via Gregory H. Urich *B.S. Elect/Computer Engineering
MINnear top
MAXnear bottom
AVGscaled
http://www.journalof911studies.com/volume/200703/GUrich/MassAndPeWtc.pdf
146
Beam Ejection
World FinancialCenter 3
147
Beam EjectionDistance from North Towerto World Financial Center 3
about 480 feet(NASA photo & scale from FEMA report)
148
Beam Ejection
• Building: WFC3 American Expresshttp://911research.wtc7.net/mirrors/guardian2/wtc/WTC_ch7.htm
• Horizontal distance: 480 ft / 160 m• Column weight: 3.5K / 12K / 23K lbs• Vertical distance (conservative): 325 m
– North Tower -- use top: 400 m– WFC3 24th floor: 75 m
• Air resistance: negligible (heavy, spearlike)
Parameters
149
Beam Ejection
• fall time = sqrt (vert-distance / 1/2 gravity) = sqrt ( 325 m / 4.8 m/sec2 ) = 8.14 sec
• horizontal speed = horiz-distance / time = 160 m / 8.14 sec = 71.1 m/sec = 44.2 mph
• Force to accelerate 4 - 11 tons to 44 mph ??
Calculation
150
So we got technical !
1. NIST’s “pile driver” theory of collapse
2. expansion of the large, fast dust clouds
3. Heavy columns thrown far and fast
And guess what?There was not ENOUGH ENERGY available
for any of these theories or observations:
151
WTC 1-2 Destruction Features
• “Pyroclastic” is used to describe volcanic dust clouds– Fine particles (solids suspended in air)– Hot inside– Heat drives rapid expansion– Little mixing with ambient air
Concrete Pulverization
152
153
154
Appendix 1:
WTC Steel Removal
155
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
• FEMA calls for further investigation, NIST doesn’t do it• Raises the larger question of WTC steel removal
156
Removal of WTC SteelNot all bite-sized pieces
Indicates not total dismemberment, but confuses issue of what melted prior to collapse
157
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”
158
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 part)
• In any case, could have labeled, docu-mented location, and saved elsewhere
159
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 perimeter columns
(under road excavated for human remains)– 1 burned column at edge of site (city: was cut off)
160
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.
161
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
162
Removal of WTC Steel“Highly sensitive”
• Nov 26: Trucks monitored by GPShttp://securitysolutions.com/ar/security_gps_job_massive/
– Sept: alleged 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”
163
Appendix 2:
Energy:A Technical Discussion
164
Let’s get technical !
1. for NIST’s “pile driver” to cause collapse?
2. to expand the large, fast dust clouds?
3. to throw heavy beams fast and far?
Was there ENOUGH ENERGY available
165
Forces and Momentum
Momentum Transfer Analysis of the Collapse of the Upper Storeys of WTC 1
Dr. Gordon Ross, June 2006http://www.journalof911studies.com/articles/Journal_5_PTransferRoss.pdf
166
Forces and Momentum
Previous momentum analyses treated floors as individual items hanging in space, instead of being interconnected, with forces moving and distributing through the structure below.
Basic idea
167
Forces and Momentum
1. Elastic phase -- load increases to failure load, at which point column is shortened 0.2% of its length; can recover (“bounce”)
2. Shortening phase -- failure load then shortens column, up to 3% of its length
3. Buckling phase -- buckling points appear, much less force needed to continue
4. Pressure wave -- moves at 4500 m/sec
Compression of Steel ColumnsWhat you need to know about . . .
168
Forces and Momentum
• Top 16 stories of North Tower (as a chunk) free-falls through a “disappeared” story
• Hits at 8.5 m/sec• At that speed, it takes .013 sec to shorten
next story by 3% (to commence buckling)• .013 sec is time for force to propagate
~60m, or 16 stories down, so all these are “moving” and thus have momentum
What happens 1
169
Forces and (conserved) Momentum
• Now 16+1 stories falling, cuts speed from 8.5 to 8 m/sec . . . BUT
• The 16 stories below are also moving slightly, and their combined momentum slows the top chunk to about 5 m/sec
• This gives additional time for the propagation wave to involve additional floors
What happens 2
170
Forces and Momentum
... and after many detailed calculations of kinetic and potential energy, elastic and plastic strain energy, and concrete pulverization energy...
171
Forces and Momentum
Energy Summary
172
Forces and Momentum
• Initial drop -- Assumption of unimpeded drop is unrealistically favorable to continued collapse
• Elastic springback -- robs some kinetic energy• Ejections -- mass is lost by material thrown
outside the tower perimeter, and energy required to move that mass outward
• The “chunk” -- energy also absorbed by damage sustained by lighter columns in “chunk”
• Other damage -- energy needed to sever floor/column connections and destroy other structural elements and floor contents
But that’s an underestimate
173
Forces and Momentum
The energy balance of the collapse moves into deficit during the plastic shortening phase of the first impacted columns showing that there would be insufficient energy available from the released potential energy of the upper section to satisfy all of the energy demands of the collision. The analysis shows that despite the assumptions made in favor of collapse continuation, vertical movement of the falling section would be arrested prior to completion of the 3% shortening phase of the impacted columns, and within 0.02 seconds after impact.
Conclusion
i.e., Collapse stops after 1 floor drop
174
2. Dust Cloud Expansion
The North Tower's Dust Cloud:
Analysis of Energy Requirements for the Expansion of the Dust Cloud Following the
Collapse of 1 World Trade Center
Jim Hoffman, January 2004 (v. 3.1)http://911research.wtc7.net/papers/dustvolume/volumev3_1.html
175
Dust Cloud Expansion
But before we get into the expansion of the dust cloud,
what about all that dust?
176
Dust Cloud Expansion
• Concrete in tower: 90,000 tons• Pulverize concrete to ~2mm size: 1.5KWh/ton
http://www.b-i-m.de/public/ibac/mueller.htm
• Energy to pulverize to 2mm: 135,000 KWh• But energy to pulverize inversely proportional to sqrt
of particle diameter, dust 0.06 mm (or less)http://www.911-strike.com/powder.htm
• Sqrt 2 = 1.4, sqrt .06 = .24 --- factor of 6• So dust creation requires ~ 6x135,000=800,000 Kwh
Pulverization Energy
177
Dust Cloud Expansion
• Somewhere between 135,000 and 800,000 KWh needed
• FEMA’s report: Tower 1 construction stored more than 111,000 KWh potential energy
• So not enough energy to pulverize concrete not as fine as observed, much less distribute it in fast-moving large clouds
• But forget that. There’s more ....
Pulverization Energy
178
Dust Cloud Expansion
The amount of thermal energy needed to expand the North Tower dust cloud as observed 30 seconds after collapse is far greater than the gravitational potential energy available from the height and mass of the tower. How?
Basic idea
179
Dust Cloud Expansion
1. expansion of gases due to heat
2. vaporization of liquids and solids3. chemical reactions resulting in a
net increase in the number of gaseous phase molecules(since this last can only be due to explosives, we’ll ignore it)
What can produce expansion?
180
Dust Cloud Expansion
1. Estimate cloud volume at given specific time before diffusion occurs
2. Factor out mixed-in air to get volume of particles of the contents originally in tower
3. Establish ratio of this to the original volume -- i.e., the volume of the tower?
4. How much energy is needed to generate that ratio of expansion for different levels of gas-expansion and liquid/solid vaporization?
Analysis steps
181
Dust Cloud ExpansionThe picture (30 seconds later) The ref points
The cylinder:Height: 200’Radius: 800’
182
Dust Cloud Expansion
• Cylinder volume: 402 million ft3
– ~1/4 is buildings, so dust = 300 million ft3 – assume 1/3 is mixed-in air (unlikely -- see
next slide) so conservative estimate ofCloud Volume = 200 million ft3
• Speed of advance observed: 25 mph
Parameters at 30 sec
183
Dust Cloud Expansion
• 25 mph is too fast for advance to be diffusion• Outside features of cloud were relatively
stable, not diffused by m/d• Sinking sections replaced by clear air• Reports of people being picked up and
carried by “solid” wall of hot dust
Due to mixing/diffusion?
184
Dust Cloud Expansion
• Tower volume:1368’ x 207’ x 207’ = 58.6 million ft3
• Cloud volume: ~200 million ft3
• Expansion ratio: 3.41 (conservative)
Expansion in 30 sec
185
Dust Cloud Expansion
• If pressure and amount (mass) stay the same, volume is proportional to absolute temperature (PV = nRT)
• If start temp was room temp (300oK), 3.4 x that is 1020oK, an increase of 680o.
• Raising air that far requires 499,500 KWh (remember: available energy = 111,000)
• But it gets worse . . .
1. Gas expansion by heat 1
186
Dust Cloud Expansion
• Such tiny dust particles (10-60 microns) will reach temp equilibrium with surrounding air very fast
• So you have to raise them 680o too• The 90,000 tons of concrete dust would
require > 11 million KWh• And if there’s water, it gets worse, but
we’ll skip that and treat water separately
1. Gas expansion by heat 2
187
Dust Cloud Expansion
• 3.4 expansion means 2.4 x tower volume would be created steam: 2.4 x 58 million ft3 = 141 million ft3 = 4 billion liters
• Volume at 100oC: steam = 1680 x water• So 2.4 million liters of water needed to
produce the entire cloud volume of steam• Conversion would require > 1.5 million KWh• Plumbing + concrete + people: not enough
2. Vaporization of water
188
Dust Cloud Expansion
• Heating of gases: would require 780oC– Ground level not that hot– High heat apparent higher in cloud (next slide)
• Water-to-steam: requires too much water, needs additional heat to get to 100oC first
• If combined: steam conversion would add to the energy requirement of gas heating, additional head needed for concrete dust
• Reduction? Early dust settling would reduce needed heat, but cloud behavior contradicts that
How much of which?
189
Dust Cloud Expansion
“Digital photographs and videos show a bright afterglow with a locus near the center of the cloud, commencing around 17 seconds after the onset of the North Tower's collapse.
“Once the afterglow started, the cloud developed large upwelling columns towering to over 600 feet, and the previously gray cloud appeared to glow with a reddish hue.”
High Temperatures
190
Dust Cloud Expansion
Conservative figures
Summary: Energy Sources and Requirements
191
Dust Cloud Expansion
• They are based on an estimate of dust cloud volume at a time long before the cloud stopped growing.
• They use a liberal estimate of the contribution of mixing to the volume (1/3).
• They ignore thermal losses due to radiation.• They ignore the resistance to expansion due to
the inertia of the suspended materials, and energy requirements to overcome it.
Why conservative?
192
Dust Cloud Expansion
Conclusion
The massive discrepancy between the gravitational energy available and the heat energy needed to drive the expansion of the dust cloud render the gravity explanation for the collapse of the North Tower (and similarly, the South Tower) untenable.
193
3. Beam Ejection
194
Beam Ejection
http://www.photolibrary.fema.gov/photodata/original/3942.jpgPhotograph by Michael Rieger taken on 09/18/2001 in New York
195
Beam EjectionStructure of Perimeter Columns
(FEMA)
196
Beam EjectionWell, maybe not 600,000 lbs...
NIST, via Gregory H. Urich *B.S. Elect/Computer Engineering
MINnear top
MAXnear bottom
AVGscaled
http://www.journalof911studies.com/volume/200703/GUrich/MassAndPeWtc.pdf
197
Beam Ejection
World FinancialCenter 3
198
Beam EjectionDistance from North Towerto World Financial Center 3
about 480 feet(NASA photo & scale from FEMA report)
199
Beam Ejection
• Building: WFC3 American Expresshttp://911research.wtc7.net/mirrors/guardian2/wtc/WTC_ch7.htm
• Horizontal distance: 480 ft / 160 m• Column weight: 3.5K / 12K / 23K lbs• Vertical distance (conservative): 325 m
– North Tower -- use top: 400 m– WFC3 24th floor: 75 m
• Air resistance: negligible (heavy, spearlike)
Parameters
200
Beam Ejection
• fall time = sqrt (vert-distance / 1/2 gravity) = sqrt ( 325 m / 4.8 m/sec2 ) = 8.14 sec
• horizontal speed = horiz-distance / time = 160 m / 8.14 sec = 71.1 m/sec = 44.2 mph
• Force to accelerate 4 - 11 tons to 44 mph ??
Calculation
201
So we got technical !
1. NIST’s “pile driver” theory of collapse
2. expansion of the large, fast dust clouds
3. Heavy columns thrown far and fast
And guess what?There was not ENOUGH ENERGY available
for any of these theories or observations: