NoahFence
Banned
It's even worse than that. It's his implication that anybody on the planet cares about the walk-off of a specific girder at a specific location in a specific manner.
It's friggin retarded.
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WTC7 and the girder walk-off between column 79 and 44
- Thread starter Gamolon
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It's even worse than that. It's his implication that anybody on the planet cares about the walk-off of a specific girder at a specific location in a specific manner.
It's friggin retarded.
tsig
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Yes, the idea that if he can show the seat was 1" wider than NIST says it was then it must be a CD is ludicrous.
Animal
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tsig
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Did anyone else notice something about the design changes:
They focused on getting people out of the building & fire protection (i.e., making sure the buildings stand longer, allowing egress). I'd also bet that there are serious changes addressing the factors (long spans & single sided girder tie-ins) that led to WTC7 collapse.
There was absolutely nothing about "you need to use stronger steel, different column placement, etc, etc. etc." so that the building will survive a full speed, fully loaded impact by a hijacked airplane."
The REAL architects & engineers recognize that this is an absolutely impossible goal to even attempt to achieve.
Which addresses directly the false claim that "the towers were designed to survive one or more impacts from jets."
We cannot achieve this goal even today, with incredible modern design tools (supercomputers & modeling).
They certainly couldn't have pulled off this feat in 1969 using slide rules & drafting machines.
They focused on getting people out of the building & fire protection (i.e., making sure the buildings stand longer, allowing egress). I'd also bet that there are serious changes addressing the factors (long spans & single sided girder tie-ins) that led to WTC7 collapse.
There was absolutely nothing about "you need to use stronger steel, different column placement, etc, etc. etc." so that the building will survive a full speed, fully loaded impact by a hijacked airplane."
The REAL architects & engineers recognize that this is an absolutely impossible goal to even attempt to achieve.
Which addresses directly the false claim that "the towers were designed to survive one or more impacts from jets."
We cannot achieve this goal even today, with incredible modern design tools (supercomputers & modeling).
They certainly couldn't have pulled off this feat in 1969 using slide rules & drafting machines.
To be fair, there are some real engineers who think future structures should be more resistant. Notable among them is Dr. Astaneh at Cal, frequently invoked here, who suggests that a more traditional column layout with thicker columns at the perimeter, and less long-span floorspace, would have fared better in the initial impacts and thus withstood the fires longer. He has repeatedly voiced his opinion that the Port Authority got away with a structural design that was more vulnerable than a similar structure would have been had it followed normal building codes, and this is plausible.
You can also get some idea of the new state of practice from Leslie Robertson's later works, notably Taipei 101, which has quite a few innovations based on the experience of 9/11.
Exactly how structures should be made more resistant in a cost-effective manner is subject to some debate. However, it is clear that no practitioner has a problem with the idea of the WTC, as built, collapsing without the help of {insert fantasy here}.
Exotic traveller
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Skilling was at the top of his field in the world when he stated the towers were built to withstand plane impacts, he was certainly no fool, and i would guess consulted with many more engineers in building the towers, one of whom was but a junior partner at that time, Robertson.Those building were state of the art, and had the best technology known to man at that time.
I am unaware of any building code changes that have been invoked because of events on 9/11, regards the towers
After looking into it, i believe towers were designed to withstand impact from a fully loaded 707, which is the equal at least, of a only partially loaded 9/11 aircraft, as they were in fact configured that day.
Could two more towers identical to wtc 1 and 2 have been able to be built say on 10 Sept 2001?, or on 12 Sept? Or have some codes been changed rendering them unsafe?
I am unaware of any building code changes that have been invoked because of events on 9/11, regards the towers
After looking into it, i believe towers were designed to withstand impact from a fully loaded 707, which is the equal at least, of a only partially loaded 9/11 aircraft, as they were in fact configured that day.
Could two more towers identical to wtc 1 and 2 have been able to be built say on 10 Sept 2001?, or on 12 Sept? Or have some codes been changed rendering them unsafe?
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ElMondoHummus
0.25 short of being half-witted
As far as the building codes and the differences in design that the Twin Towers had, that's laid out in the NIST report. I'll let engineers who post here elaborate on what those were.
As far as Robertson's concerned: He came out and said that they didn't consider the effects of the sorts of fires that can result from such an impact in their analyses. Back then, such effects could be estimated, but not with the precision that modern computing allows, and IIRC they were only doing a rough verbal estimate to begin with (someone correct me if I'm wrong about this; I'm relying on memory). Anyway, what presumptions they did have about the fires were clear in the design: They did not expect fires to consume entire floors at once, they presumed that the sprinkler systems would help contain fire spread, etc.
Just keep in mind that, if we're going to discuss things in terms of the towers surviving the jet impacts, keep in mind that they did. Admirably, in fact. They were done in by the fires exacerbating the damage done by the impacts to the point where parts of the structure could no longer hold. So the thing to consider where 9/11 and the Twin Towers is concerned is not just a statement of the buildings surviving the impacts; it's to recognize that they did, but the fires had their effect too. It's important to recognize and use all the context available, not just isolated snippets of fact.
NoahFence
Banned
LSSBB
Devilish Dictionarian
Rebunking.
ElMondoHummus
0.25 short of being half-witted
Whoops, I misunderstood. I took that post in the context of Ryan's where he was talking about Astaneh-Asl and then accidentally lept to the topic of Twin Towers differences from code at the time they were built. I should've read more closely; that wasn't the topic. Yes, Astaneh-Asl has done much research into the design differences that sprung from Twin Towers design deviations from then existent code. And those changes were the ones laid out in the NIST report, and didn't really seem controversial from what I could tell (Note: Seem. Astaneh-Asl obviously believes differently, and he's got a lot of excellent professional standing to base that on, so it's a legitimately open question).
But right, on a reread, I see that the question was about code and design now, in these times. Anyway, Noah's correct: The Twin Towers could not be rebuilt exactly in the same way today. Construction code has indeed changed since then. Recall that the entire purpose of the NIST report was to gain knowledge about building performance under extreme conditions that could be used toOr in short, the charter behind the NIST report was to identify what failures occurred in order to add to the body of engineering knowledge and allow relevant agencies worldwide to change construction codes. And that's exactly what happened, as Newton's Bit has shown.
Keep in mind that this is a slow process; if I remember correctly, the ICC is still evaluating code changes based on the NIST report. So this is still an ongoing process, if I'm right.
But right, on a reread, I see that the question was about code and design now, in these times. Anyway, Noah's correct: The Twin Towers could not be rebuilt exactly in the same way today. Construction code has indeed changed since then. Recall that the entire purpose of the NIST report was to gain knowledge about building performance under extreme conditions that could be used to
Keep in mind that this is a slow process; if I remember correctly, the ICC is still evaluating code changes based on the NIST report. So this is still an ongoing process, if I'm right.
Animal
Master Poster
In reality, the towers were not designed to resist the impact of an airplane. They were designed to resist the wind loads (and gravity loads) of a 110 story building. An aircraft impact would provide small loads than the design wind loads. But it is much sexier to proclaim to be aircraft resistant than wind resistant to the uniformed masses.
In short, no. Codes have evolved quite a bit since the 1960's, the basic building code is at least three times as long. (and 20 time more expense to purchase
)Clayton Moore
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It never happened without explosives but rubble would splay. It would protect/buffer the subsequent lower floors from being affected as the initial contact instance.
Tony Szamboti
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There are also others who have done analyses showing that if the perimeter columns were heavier there would have been less damage and a greater chance for the building to survive.
However, it really doesn't matter that the aircraft penetrated the buildings, as we also know from analyses that the 30+ degree rolled wings would not have gotten much past the perimeter due to impacting the floors edge on at several levels. Now it is just a 16.5 foot diameter fuselage that is moving through the building. A 207 foot square grid type structure would easily be able to take a 20 foot diameter hole completely through it without any overall potential for collapse. Given the fact that we all see that the aircraft impact on the north face of the North Tower is not where the collapse initiated, the whole aircraft impact causing the collapse point is somewhat put to rest, and NIST did not use it except to say the impacts removed fireproofing.
The problem with the NIST theory is that when looking at their debris propagation and velocity analysis and the shotgun tests with the low velocity misfire, which did not remove fireproofing, it is clear that there isn't enough velocity at the complete opposite side of the building to remove the fireproofing. Additionally, with the impact occurring at a 10.6 degree downward pitch between the 95th and 96th stories most of the debris would have been a number of stories below the south side of the 98th floor, where they want to say overheated trusses pulled in the south exterior wall. The removal of fireproofing from floor trusses on the opposite side of the building from where the impact occurred, and above where the actual somewhat slow moving debris field (at that point) would have been, is not a tenable theory.
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NoahFence
Banned
I wonder what would happen if you added a massive fireball to your cute little scenario, sort of like the one that actually happened here in reality land.
You truthers are always forgetting something, aren't you? You talk about fire, but forget to mention the plane impacts. Then you mention the impact, but you just HAVE to find a way of making them seem insignificant, so you forget about the fireball.
I'd love to see a truther try to give honesty a go. Just for one post. Baby steps.
You truthers are always forgetting something, aren't you? You talk about fire, but forget to mention the plane impacts. Then you mention the impact, but you just HAVE to find a way of making them seem insignificant, so you forget about the fireball.
I'd love to see a truther try to give honesty a go. Just for one post. Baby steps.
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Animal
Master Poster
I don't think any troofer has ever worked with spray on insulation either. The stuff would delaminate from roof decks just from people walking on it.....and that was post 911.
Tony Szamboti
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They do and so does the landing gear, and I should have included them for completeness.
Excluding the fan, which would have been structurally somewhat too weak to cause damage, and only counting the more solid turbojet portion of the engine, which included the compressor and combustion chambers, the engines would have been about 5 feet in diameter.
The landing gear was solid and its damage would have been similar to that of the engines.
The fuselage cross section was about 9% of the cross sectional area of one story. The engines and landing were about 8% of the fuselage in area each. In total all five items are about 12% of the area of one story. So even if they took out everything in their path, by volume alone the fuselage, engines, and landing gear could not do nearly enough damage to the structure to effect an overall collapse. It would have been like Frank Mancini's analogy of piercing a mosquito net with a pencil. Make that about five pencils and it still doesn't affect the structural grid enough to break it down.
What makes it look like a giant hole is from the wings, but they couldn't get very far from the exterior they impacted.
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NoahFence
Banned
....still leaving something out?
Tony Szamboti
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NIST claims, in the case of the towers, that the fires were an issue only when coupled with the removal of fireproofing. They even said if the fireproofing wasn't removed the buildings would still be standing.
Well the fireproofing could not have been removed where they said it was, due to the debris field velocity and position, so here we have another impossibility.
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