I know you are not an architect and I've answered these questions before but I also know you are all about wasting my time and have no real interest in the truth.
Gravy has my ARB (that's the Architects Registration Board) and RIBA (Royal Institute of British Architects) registration details which confirm - much to your disappointment, no doubt - that I am indeed a qualified architect with 15 years post-qualification experience.
The elevator guide rail SUPPORT steel does not have to stick up over the temporary floor in the core. The priority of the job was to keep the elevator acess as far up as possible. Meaning that every now and then, the guide rail support steel did stick up over the top floor.
Well Chris, there's a small problem there. You see the lift machinery at WTC generally went at the top of the shafts. So there's no point in installing them until you get to the plant level. On construction sites, we use temporary lifts pretty much until the final fitting out stage. Yes, even in tall buildings.
Only 40 feet of concrete can be poured before hydrostatic pressures of concrete blow out wood forms. Engineers determined that the unequal loading of the kangaroo cranes working together could easily over load and damage the steel framework so limited the steel over the concrete to 7 floors. The Steelworker I interviewed remembered this. There were a few time where exceptions were allowed but cranes must have been limited in their loads during those phases.
Bollocks.
The forms are always inside the interior box columns and the rebar inside the steel framework in shadow.
We'd still be able to see the timber forms and their supporting framework. If you've ever seen in-situ concrete work you'd realise just how much formwork and support was required. It would not slide into invisibility in photographs.
The documentary noted a number of times that the big slowdown in the concrete core construction was because of a shortage of welders that had security clearance to perform the butt weld in the high tensile steel rebar used in the concrete shear walls of the core. A security clearnace was required because of the thick "special plastic coating" on the rebar. Later the videographers discovered that the reason the security clearance was required was because the rebar s plastic coating was "flammable". The lateral junctions were tied in a normal fashion. The horizontal bar had the same "special plastic coating".
Bollocks. Steel reinforcement is not welded and does not particularly need to be. It is tied or clipped. Welding is neither necessary or cost effective; do you really understand the structural issues?
I'd especially love you to tell me how the complex lateral junctions would work if they were welded.
Your question is unclear. If it is "How much rebar", I can say I don't know. The rebar is always centered in concrete walls. The rebar was on 4 foot centers and 3" inches in diameter all the way to the top.
Wrong again, mate. You really don't understand structures, do you?
Reinforcement only serves to take the tension loads, as concrete is only good in compression. Therefore the reinforcement is placed where the tensile loads are; so, for example, on a floor it goes on the underside and on a balcony on the topside. If (haha) WTC had a concrete core the arrangement of the reinforcement would have been rather complex.
I would have thought they would have mentioned that in your documentary.
Anyway the reason I ask you about the quantity of rebar is because it's important in debunking your argument. You see, you'd have to look at how much rebar was required, especially at the complex junctions, then the amount of concrete to cover it.
I think you'll find that it's rather a lot, and certainly the kind of thickness where it would be visible in construction photgraphs and the like.
How about you answer my question about how much added resistance to torsion that interior steel columns add to a square set of perimeter walls when the field of steel columns is about 1/2 the dimension of the square?
It's a non-sensical question, Chris. Let me ask you one; are you using elastic or plastic structural theory to consider this?
Steel flexes in very long members whether vertical or horizontal. In the documentary they played a clip of the Tacoma narrow bridge twisting.
Concrete is rigid and absorbed lateral forces as well as torsion. That was the role of the concrete core in the WTC towers.
Aha, the Tacoma Narrows. We did that in structures (gasp, horror, 4 years of it as part of our degrees). You're trying to use a cable suspension bridge as some sort of analagy. Apples and oranges spring to mind.
Anyway you fail on so many levels:
1. Steel is just as sutiable and strong as concrete; resistance to forces all comes down to design. It may be helpful if you (well, the sane readers) think of all framed structures as girder beams, where the floors and other members act as the web. The important thing is not the material, but rather how the web and flanges (ahem) interact with each other structurally.
2. Concrete is only strong in compression. Steel is strong in tension and compression. "Lateral forces" is irrelevant under such circumstances.
3. Tall buildings aren't designed to be completely rigid, mate. This may come as a shock to you.
Basically you're a fraud Chris; you don't understand even basic structural issues, and instead apply a ham fisted layman's interpretation onto what are actually perfectly clear photographs of a steel core getting built.
Performance art, or a troll. I don't buy delusional any more.
