Christophera
Banned
- Joined
- May 25, 2006
- Messages
- 2,760
But yet they discussed it for over an hour in an documentary, whilst it was highly secret. How is that, Chris?
In 1990 it was not a secret, obviously. It was common knowledge amongst people who knew architecture. Those people still know, they just don't know about the FEMA lie, or perhaps approve of it.
Also, did the core have DIAGONAL cross bracing?
No. It was a special shear wall construction. Rodger Harris made some good points about rebar sizes, the center to center of 4 foot seemed a lot to him. In the discussion regarding wall thickness I had with beachnut where he couldn't understand why the wall was only 2 foot thick at the top, I realized that the horizontal rebar was very dense which served to work with the 3 inch rebar on 4 foot centers to enhance the diagonal shear strength of the walls.
The points Rodger made got me comparing, intuitively, (I am not an engineer), the rebar in the core walls to standard concrete walls I've seen and the walls or core really was designed to deal with torsion in a big way. The winds put a big twist on the tower at the top as the faces would "fly".
The image of the rebar
shows the rebar tips sloping. The documentary actually explained, indirectly, why that happened like that. Two reasons, 1.) The rebar butt welds were done on the slope by specification to reduce the chance of a fracture across the core on a horizontal line, torsion resistence. The sloping rebar welds followed the concrete which was mounded up inside the forms to a high point at the corners forming a sawtooth joint between pours making the core more resistant to torsion.
2.) The rebar on the side in the linked image sat out in the weather and the special plastic coating lost its "protective viability", stated in the documentary. In reality the plastic explosive had lost its viability and that is why the vertical rebar still stood. The horizontal rebar coating was fresh and blew the concrete off to expose the tops on a slope.
