I would bet a years pay that you can't get a scale model to initiate a global collapse with one wall bowed inward and then propagate without a jolt.
Medium length version - just right.
Heiwa, Gage, Chandler et al treat the upper and lower WTC columns, joists and slab structures as homogeneous lumps of material and believe the smaller lump could not have crushed the larger lump, CD must have been used.
Tony Szamboti believes that if the smaller upper block columns fell axially onto the larger lower block columns, there should have been a "jolt" at columns impact and the lower block columns would have arrested the collapse. Since the collapse was not arrested, and TS did not see a " jolt", TS believes CD must have been used
But That Is Not What Happened. This Is What Happened:
- BasqueArch, Arch as in Architect licensed 30 years
1) WTC2. (and WTC1 similar) The east wall bowed and collapsed first . We know this because the building began the tilt that direction.
2)The east wall and upper block pivoted (tilted) down . The tilting upper mass applied a horizontal torque (not vertical compression force) to the remaining heat and impact damaged vertical columns that bent them, and the columns fractured at the point where the columns bent. When all the columns fractured, the upper mass stopped tilting and fell vertically down, The top upper block columns punched through the lower floor slabs.
Before and during WTC2 initial collapse showing 3 foot columns vertical displacement.
[qimg]http://911stories.googlepages.com/ST1.jpg/ST1-full.jpg[/qimg]
3) 128,000 lbs per columns square foot (static load only) landed onto the 2.5” to 4” thick floor slab x 14" x 14" area design loaded at 330 lb / SF and failed (128,000 lb/sf column load > 330 lb/sf slab design load ).
When all the columns above fractured , the block stopped tilting, and the columns punched through the slab below. The displaced columns above did not hit the off center columns below.
4) We know the floor slabs failed first before the columns failed because of the visual evidence . Had the columns below failed before the floor slabs, the columns would have failed in buckling (or decapitated by CD) with portions of the floor structures still attached to the columns and the perimeter wall assemblies would have fallen vertically nearly “onto its own footprint”. There is no evidence of universal buckling of columns at the column body that would indicate column crushing forces or columns decapitation that would show CD. After the floors pancaked, the unsupported perimeter and core columns failed at the connections and toppled onto the ground.
Picture of WTC1 uncrushed columns, floors failed first then columns toppled outward, not onto “its own footprint” had the load path been axially through the perimeter columns or CD'd.
[qimg]http://www.911myths.com/assets/images/columns.jpg[/qimg]
5) Therefore it doesn’t matter if “ you would find that they all have buckling stresses near the yield stress.” because the columns below did not fail by crushing or CD. They toppled after the floors pancaked past them.
6) Therefore it doesn’t matter if “the 3.00 to 1 factor of safety for the core columns was calculated using Gregory Urich's mass analysis.” because the columns below did not fail by crushing or CD. They toppled after the floors pancaked past them.
7) Therefore it doesn’t matter if ” the columns on each story were designed to have the same unit stress to preclude differential deflections and floor warpage between the core and perimeter.” because the columns below did not fail by crushing or CD. They toppled after the floors pancaked past them.
and so on ...
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There is great confusion among the masses about Bazant’s collapse theory.
“For our purpose, we may assume that all the impact forces go into the columns and are distributed among them equally. Unlikely though such a distribution may be, it is nevertheless the most optimistic hypothesis to make because the resistance of the building to the impact is, for such a distribution, the highest. If the building is found to fail under a uniform distribution of the impact forces, it would fail under any other distribution.” - Bazant
[qimg]http://911review.com/coverup/fantasy/imgs/figure4.gif[/qimg]
From Bazant -
Fig. 4. Scenario of tilting of upper part of building ~South Tower - showing horizontal bending forces and displacement of upper and lower columns.
From Bazant’s first paper.
http://www.civil.northwestern.edu/people/bazant/PDFs/Papers/405.pdf
Summary:
WTC1,2 failed by gravity collapse only.
On the weakest wall the perimeter columns failed, the upper stories tilted (WTC2), the remainder of the columns fractured, the tilt stopped , the upper stories fell straight down, the displaced columns above punched through the floor slab below - not hit the columns below - the floor slabs pancaked, and the unsupported perimeter and core columns then toppled to the ground.
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You can’t reason someone out of something they were not reasoned into. -Swift[/QUOTE]
