9/11

An excellent video of the true timing of the wtc 1 collapse

20 seconds for the main collapse, another 10 or so seconds for the remaining centre columns to fall

 

Another excellent video summarizing parts of the NIST report, video a little more entertaining that reading

 

Finally...... This Thread Can Be Laid To Rest.....



Cheers Glen.

 

Well done VG

 

90,000 tons of concrete, 180 million pounds. 1/2 structural lightweight, 1/2 structural regular concrete, in place densities 90 to 115 lb/ ft3, 140 to 150 lb/ ft3

782608 ft3 + 600000 ft3 = 1,382,608 ft3

Volume of 1 floor of wtc tower = 12.37 ft high by 210 ft wide by 210 ft deep = 545, 517 cubic feet. Just one floor.

So, by volume, if you seperated all building materials in the the towers.

Out of 110 stories, the total concrete wouldnt even fill 3 stories

Let me say that again, by volume, less than 3 floors out of 110 floors of the towers were concrete

Its not the case that it was all pulverized, its a case that no one had s clue how much there should have been.

Another thing all truthers should have worked out in 17 years

 

Well Done VG......



Cheers Glen.

 

Let's put you into perspective here. You claimed that the FEMA report says that "the WHOLE structural intergrity of wtc 1, including all the columns in that " intact core structure" were compromised by the collapse of wtc 2." That proved to be a lie on your part. You seem to not understand what that did to your credibility.

But wait! There's more. You claimed that the NIST report. confirms that "Theres no singular defined "upper block" once everything starts to give way." So far, that, too, has proved to be a lie on your part. And once again, you seem to not understand what that did to your credibility here; especially when you simply refuse to admit that you were just making shit up. And unfortunately, your supporters here show the same propensity to ignore what makes them uncomfortable.

And not surprisingly, your video here shows an animation of the pancaking of floors which completely leaves the core structure out of the equation. You didn't notice that, did you? Another problem with this theory is that there is no evidence of a stack of floors at the base of the Tower after collapse like other buildings that have fallen in similar fashion. You must also believe that the floor connections to the core and perimeter columns were so strong as to pull them down. This contradicts the idea that the floors broke away and pancaked at virtual freefall speed for at least the first 360 feet of collapse. If you hadn't started out with the idea that nothing about the collapse was fishy, you wouldn't find yourself stuck with a theory that includes the idea that the floors were holding up the core instead of the opposite being true.

So, to sum up your position, you believe that, even though the floor connections were strong enough to pull down the core structure that they were connected to, you also believe that they all broke away fast enough to facilitate a virtual freefall collapse; not only collapsing themselves all around the Tower at once, but also crushing the intact core structure below.

Well Done VG...…

 

You are muddling up terms again, a pancake theory of collapse refers to floors failing sequentually, one on top off the other top down or bottom up, like a stack of pancakes. Hence the name pancake theory.

Thats not what the NIST report says, thats not what video shows.

We are back in Sargent Shulltz mode again.

Until you present a clearly defined alternative you are arguing the towers didnt fall down.

The trouble with you repeating "intact core structure" for 40 pages is that as soon as any event occurs that could have jolted out a single one of those columns, bent out a mere few right angles, well then your "intact core structure" wasnt quite as intact as it was on the 10th of september 2001. Not enough to trigger collapse, but certainly enough to make it that little bit easier for the top floors to plough through the bottom ones.

We will eventually get to what the Fema report says about the effect of tower 2s collapse on tower 1, but I got another couple dozen right in your face the whole time doozies before that?

Did you really go 17 years seeing that News report with Peter Jennings asking "where is all the rubble?" Never asking yourself, well...errr...how much rubble should there be?

Did you really go 17 years thinking all those photos of office workers covered in dust.They were covered in pulverized concrete? Really? 17 years?

 

Your point is clear and concise storch. Great job, you win the argument.

 

The video showed that the NIST misrepresented the elements involved in the WTC structure; it omitted the core structure in its animated illustration. And so do you.

Remember this:

"There was no internal intact structure pushing upwards. The external steel columns were holding the load, once they gave way, KABOOM . . ."

Where did you get that bit of knowledge from?

Unless you can explain how it is that you know that the core structure below the upper block was not there to offer resistance, you have no basis for making such a claim. Hell, even the NIST referred to the lower core structure as "intact." So your comments show that you've missed the bus on that one. And to that point, perhaps you will explain how the NIST had determined that 13% of the core columns had been severed. After all, the FEMA had conceded that the number of core columns that had been destroyed is unknown. So . . .

But this all comes back to the bottom line here. The pure bullshit reasoning that the upper block of the Tower basically passed through the section of Tower directly below it for 360 feet at just 40 feet shy of freefall. Like I said, even if we allow for the impact of the descending upper block to crush the lower block directly below it, it can't crush it while maintaining the downward acceleration as seen in videos, and that's because an increased force on the lower block of the Tower must be accompanied by a decrease in the momentum and speed of the falling upper block, owing to the intact core structure below it. That is not even debatable, but here you are trying to make the case for the rest of the Tower having no effect during collision. Silly, huh?

And of course everyone knows that you will eventually produce the segment of the FEMA report that you claim exists which confirms that all of the core columns of the North Tower were compromised by the collapse of the South Tower. I'm sure everyone understands that you wouldn't have said it if it weren't true, and that you must surely be waiting for the right moment for dramatic effect.

 

No, you are getting mixed up again.

External means the columns on the outside of the building. Internal means the columns in the core, the centre of the building

Several floors below the point of intact start to collapse, so not intact, along with the floor trusses, pulling the external columns inward (remember external means on the outside) so any load they were left holding is not supported anymore. Kaboom.

It means the initiation of the collapse is a couple seconds before what you see on the outside, so 5 seconds is really 7, 8 seconds, so not really near freefall at all, sorry "virtual" freefall


Just watch the video again, pause, skip back several times. Should clear things up for you

 

I think that most people miss the point that a huge amount of structural planning goes into ensuring that buildings in a city and in close proximity to others are designed to be demolished in their own footprint with minimal use of explosive.

The mass generated on the floors hit by the planes, simply triggered the process accidentally.
As soon as the mass was sufficient for one floor to shear its bearings onto the upright steels, it hit the floor below like a pile-driver and nothing was going to stop the collapse.

Whether the terrorists knew that the points of impact would trigger the process is another matter.

 

Osama bin Liner

 

Uh, yeah, I know the difference between the perimeter and core structures. But you've neglected to answer the question of how you--or the NIST--determined that 13% of the core columns in the North Tower were destroyed. But let's assume, for the sake of argument, that 6 core columns were severed. That leaves 41 columns. For some reason, you've decided that even with a redundancy built into the Tower, the loss of 6 columns would cause the entire core structure to just crumble into itself.

By the same token, approximately 33 of the perimeter columns were compromised. And your position is that the remaining 207 columns would have suddenly crumbled into themselves. The truth is that the remaining perimeter columns would have easily carried the extra load due to the missing 33 columns.

Here is a quote from Engineering News Record, April 2, 1964.

A design procedure that will be used for structural framing of the 1,350-ft high twin towers of the World Trade Center in New York City gives the exterior columns (perimeter columns) tremendous reserve strength. Live loads on these columns can be increased more than 2,000% before failure occurs.

So let's recap. You are of the opinion that the destruction of 6 core columns and 33 perimeter columns would cause the rest of the columns in the Tower to just give up the ghost. I am of the opinion that that's just so much bullshit.

 

This is harder than Tetris

 

Do you have any proof that the WTCs were designed to self-demolished if circumstances warrant?

 

The world is yet to have a major earthquake in modern times close enough to a major city with skyscrapers more than 300m tall.

The Tohoku earthquake 2011 was the closest so far, several articles in the papers congradulating building codes on no skyscrapers collapsing, but the earthquake wasnt quite close enough.

The numbers on the Old Richter scale correspond to mesurements from 100 km away a 9.0 is a 9.0 from 100 km away

Its not possible to build a skyscraper over 300m that can withstand an 8.5 in that 100 km zone even for a short duration.


So just like the world had never seen the real effects of jetliners crashing into skyscrapers. The world is yet to see the effects of an 8.5 earthquake or higher under a city with buildings over 300m

Tohoku still did this:

A March 2018 agency report listed 121,776 buildings totally collapsed, with a further 280,923 buildings "half collapsed", and another 726,574 buildings partially damaged.

That was 2011, you'll note how little the rest of the world heard about it/ payed attention

Plenty of coverage about the resulting Tsunami and what it did to Fukishima. But not much attention to the earthquake itself. 121,000 buildings totally collapsed, thats a shit load of buildings

 

Dude, this is getting really old now

1. That is not what he said

2. There is always a strength vs flexibiity trade off with any tall building. Make them more rigid to withstand cyclones the heavier and costlier they are and more likely they are to fall in an earthquake. Base location to earthquake proof heavier more rigid tall buildings but that just blows out the cost to ridiculous levels.

DO YOUR HOMEWORK!

 

It's comforting how many structural engineers post on Hip Forums