well.good chats guys, im sorry if offended anyone, am just more than a bit passionate concerning our nation. Plus after serving and seeing how things truely are, the abject horrors, its real hard to adjust and alter your perception.


Live free or die guys.

BED666,

Thank you for serving this country.

Now, back to the ae911 site.

Originally posted by etshrtslr

When the buildings were standing the lower floors were still carrying the same load as they were when the collapse started

Here's an example that might make sense. I can take a bowling ball and set it on top of a cardboard box, and the box will hold up the bowling ball. But if I lift up the bolwing ball and drop it from 4 feet about the cardboard box, the box will be crushed.

The mass of the WTCs above the impact area had to be in the range of thoudands of tons. When this much mass begins to accelerate downward at 32 ft/s2, the force hitting the floors below is F = m x a. So the load on the floors below was not the same. The accelerating mass of the upper floors was too much force for the steel beams to withstand. And as each subsequent floor collapsed, the mass, and therefore the force, compounded.

Originally posted by blueyedevil666
well.good chats guys, im sorry if offended anyone, am just more than a bit passionate concerning our nation. Plus after serving and seeing how things truely are, the abject horrors, its real hard to adjust and alter your perception.


Live free or die guys.

Thank you for your service to our country.

I love this country also....I think its the best in the world.

I am also passionate about defending our country against any threats and finding the truth.

With that being said I think the best we can do on this topic is agree to disagree.

Peace

Originally posted by nick7261


Here's an example that might make sense. I can take a bowling ball and set it on top of a cardboard box, and the box will hold up the bowling ball. But if I lift up the bolwing ball and drop it from 4 feet about the cardboard box, the box will be crushed.

Thats a good analogy but I dont see how it accounts for the free fall speed of the collapse the pulverization of concrete (even above the impact point) and beams and material being ejected over 600ft.

Originally posted by nick7261
The accelerating mass of the upper floors was too much force for the steel beams to withstand.

Problem is. What caused the floors above to accelerate down when steel in fire deforms and bends? What I mean is that steel doesn't just give way under heat at one instance. It bends and deflects and becomes malliable. So, what would cause the upper cap to "drop" in the first place rather than deform and bend more slowly?

Originally posted by coughymachine
I browsed the forum earlier and have to say, I was a little disappointed with what I saw (maybe I didn't see enough). I had hoped and expected the discussion to be almost entirely factually based, and include lots of 'stuff' I didn't understand about the way buildings behave, energy calculations, etc, etc. Instead, it seems the nature of the debate is being dictated by the de-bunkers who have, for the most part, got people arguing about the motive. We have plenty of that here and elsewhere.

I hope this is simply because the board is new and the 'specialists' have yet to engage.

I haven't even looked at the page yet, but that's what I woulda guesed. when a new group, say Pirates for 9/11 Truth, appears I honestly don't expect something serious. I hope Griff can help steer them that way a bit.

In fact if they want to stand out what they could do is focus on something unknown and new, but non-conspiratorial. Just plain truth, something most people can grasp once they see it. Analyze it well, show your skills, trump the officials in some way. AS you work on the big stuff, also in an expertly and accurate way. Which means risking a non-"9/11 Truth" outcome if you're honest. It's all in the degree of risk, and let reality take care of that.

I won't have much to say anyway since I'm still an idiot on the WTC construction. But if all goes well, perhaps their findings can help me ACTUALLY understand rather than being bored with more plausible-sounding but unanswerable scenarios... More floor plans and stuff! Peer reviews! Something to make us smarter.

Unless that's too dangerous.

Originally posted by etshrtslr

Thats a good analogy but I dont see how it accounts for the free fall speed of the collapse the pulverization of concrete (even above the impact point) and beams and material being ejected over 600ft.

The free fall speed, the pulverization of the concrete, and the ejected beams is another matter.

First, I'm not sure that the free fall speed is an accurate description. Nevertheless, it's close enough to raise the question of why didn't the lower floors slow down the speed of the collapse? My only guess would be that the force from the weight of the upper floors was entirely disproportionate to what the lower floors could bear. Without doing calculations, this is just a guess.

The pulverization of the concrete is easier to explain. The concrete consisted mainly of the floor slabs. The amount of energy contained in the massive falling structure hitting the floor slabs beneath was far too much for the concrete to withstand. I can smash concrete with a sledge hammer. Imagine the force of thousands of tons of mass, with steel beams forming a grid, slicing through the concrete floor slabs beneath. It would be like hitting a snowball with tennis racket.

The ejected steel beams also represent the dissapation of the enormous kinetic energy being released. Did you ever see Gallagher do his bit of hitting a watermelon with a sledge hammer? The watermelon pieces flew 20 feet out into the audience. Same principle applies when thousands of tons of concrete and steel are slamming down on the concrete and steel below. Same thing happens when you chop a tree with an axe -pieces of the tree go flying outward in all directions.

Originally posted by nick7261

The pulverization of the concrete is easier to explain.

Nick7261,

While you may be able to chip away concrete with the point force of a sledge hammer - I defy anyone to do so while a 4" reinforced pan floor system is resting on the cardboard tube analogy. The force of your blow would be used in-part to overcome the resistive strength at the edges of the box, allowing successive floors to escape unharmed to the levels below.

Ultimately we must end up with some form of stories-high pancake that NIST either now does not or never did support.

I believe conservation of energy / momentum says that if you use energy to pulverize concrete it cant go to rubberizing / vacating over-engineered and undamaged steel core columns.

-Scrap

Originally posted by Griff

Problem is. What caused the floors above to accelerate down when steel in fire deforms and bends? What I mean is that steel doesn't just give way under heat at one instance. It bends and deflects and becomes malliable. So, what would cause the upper cap to "drop" in the first place rather than deform and bend more slowly?

I hate to admit that I sometimes literally stay awake at night wondering this same thing (especially now that "Lost" is over for the season.)

Here's the only thing I can think of that might make sense...

First, steel doesn't have to be heated to bend, or even break. Here's a pic I found of some guy who had the steel pole supporting his satellite antenna break during a wind storm.




But of course, heating the steel will help make it malliable like you said. Here is a photo of one of the WTC beams that was bent all the way backwards:




So here's what I'm thinking:

We're not really sure of how many steel beams were taken out by the initial impact from the plane. In any case, we know some finite number of beams were taken out when the planes hit.

The remaining weight of the upper portion of the towers now was being supported by fewer steel beams. WTC2 was seen to have it's west face buckle because the support beams on the west side were damaged by the initial impact. Once the west face buckled, a domino effect could have taken place. As soon as one beam failed, the entire load of the upper structure was now bearing down on fewer beams, which in turn would fail one after another, starting with the weakest, until a tipping point was reached.

Without knowing the actual damage to the internal core from the plane at WTC1, everything about its collapse is only speculation. That said, knowing the beam damage at the Pentagon, and knowing where FL 11 hit WTC1, it's not unreasonable to think that the core columns were severely compromised at WTC1, which led to the upper floors collapsing onto the lower floors.

Of course, WTC7 is an entirely different story. Personally, I think all this discussion about WTC1 and WTC2 is a major distraction from getting to the bottom of WTC7.

Originally posted by nick7261
Same thing happens when you chop a tree with an axe -pieces of the tree go flying outward in all directions.

- Considering all of our above comments - my speculation is not meant to belittle anyone- and simply address ideas and statments made.

I feel the magic axe analogy is one that can ‘cut’ both ways. If we take said axe and swipe a tall tree in the thick of the trunk directly below the lowest branches what happens in the real world? The tree is not split to oblivion down to its root system by the upper-section crashing down. Even if a metal tree house is installed in the canopy.

Obviously the magic axe does not exist as Griff I believe alluded to above. Steel does not vaporize at once across an entire floor and the fire could not get hot enough based on the observed attack – check the NIST metal samples. I am paraphrasing from memory but no steel samples showed over 600C. Not enough to fatigue steel – much less vaporize.


[edit on 31-5-2007 by scrapple]

Originally posted by Caustic Logic


Which means risking a non-"9/11 Truth" outcome if you're honest. It's all in the degree of risk, and let reality take care of that.

I for one would love to have a non 9/11 Truth outcome. Because something otherwise implies a far different world we will live in from today.

I do think we all must endure to find out the TRUTH whatever it may be and regardless of the consequences. If 9/11 was indeed a conspiracy of something other that radical Muslims then I consider it our patriotic duty to find out. I do not want to live under the illusion that all is well if in fact it is not.

The only thing I feel certain of is to date we have not been told everything we should have been told about what happened on 9/11 and all the evidence has not been disclosed.

Originally posted by scrapple

While you may be able to chip away concrete with the point force of a sledge hammer - I defy anyone to do so while a 4" reinforced pan floor system is resting on the cardboard tube analogy. The force of your blow would be used in-part to overcome the resistive strength at the edges of the box, allowing successive floors to escape unharmed to the levels below.

Ultimately we must end up with some form of stories-high pancake that NIST either now does not or never did support.

I believe conservation of energy / momentum says that if you use energy to pulverize concrete it cant go to rubberizing / vacating over-engineered and undamaged steel core columns.

I don't know about this. It depends on how much energy we're talking about.

A better metaphor might be putting a bowling ball on my glass kitchen table top. The glass table will hold a lot of weight at rest. But I'm sure if I dropped the bowling ball from just 2 feet above the glass table, the table would shatter.

Now what if the glass table top developed a crack in it to weaken it's ability to support the mass above it? At some point, a breaking point would be reached, and a bowling ball resting on top of the table would break through the weakened glass. I would also guess that if there were 100 glass table tops 8 feet apart, the bowling ball would continue plow right through every one at close to free fall speed until it hit the floor.

I.e., if the first floor doesn't provide enough resistance to significantly slow the mass down, then the subsequent floor won't have a chance to stop it either. Remember, the mass is not just falling, it's *accelerating* at a free fall rate of acceleration, 32 ft/s2. Unless the first floor of resistance can completely stop the acceleration, the mass will strike the next floor down with even more force.

In fact, when you add the weight of the first collapsed floor to the next, even if the acceleration is mitigated, the force would be greater because of the additional mass.

What really needs to be done at this point are the real calculations. The mass of each floor of the WTC must be known first. Next, the load bearing abilities of the steel trusses must be known. Finally, it would be helpful to know exactly which columns were taken out by the initial impact.

Without being able to quantify this information, all this is just pure speculation from both sides.

Originally posted by scrapple

I feel the magic axe analogy is one that can ‘cut’ both ways. If we take said axe and swipe a tall tree in the thick of the trunk directly below the lowest branches what happens in the real world? The tree is not split to oblivion down to its root system by the upper-section crashing down. Even if a metal tree house is installed in the canopy.

You're taking the axe analogy out of context. I described this analogy strictly to give a real life example that would explain the steel beams being expelled from the collapsing towers. The idea is that when something is hit with a great force, particles will fly out in all directions.

The tops of the towers hit the lower floors with a tremendous force, due to their enormous mass. It seems reasonable that this force would cause steel beams and concrete to be ejected in all directions.

I believe you have the right concept Nick. The thing that gets me though is how did all the columns telescope into themselves from falling mass? Even after the first buckle that made everything explode (for lack of a better word). How did that mass pile drive the remaining column down to nothing? Am I making sense?

Think of it this way. Try to buckle a column by pouring sand on it. Even if the sand is thousands of tons and the force is from 1 + stories, I believe the sand would take the path of least resistance and fall to the sides of the column rather than telescope it into itself. Of course, I could always be wrong.

what nick said is exactly where i was going with my view on the whole event, physically...in that it is possible even plausible that this could occur. Thank you Nick for your very descriptive notation on what happened.

BTW guys keep in mind....i live and work in nyc and had been through the towers many many times as they housed a central hub of new york city transit subways and the NJ path system.....when exiting any one of the trains, you found yourself at least 5 stories below sea level...the sub-level structure of the WTC was immense....imagine a 5 story basement, coupled with another few stories of transit/electrical/sewerage systems and you have quite a big hole to fill with debris....maybe this helps in addressing the state of the remaining concrete after the collapse.

Originally posted by Griff
I believe you have the right concept Nick. The thing that gets me though is how did all the columns telescope into themselves from falling mass? Even after the first buckle that made everything explode (for lack of a better word). How did that mass pile drive the remaining column down to nothing? Am I making sense?

Think of it this way. Try to buckle a column by pouring sand on it. Even if the sand is thousands of tons and the force is from 1 + stories, I believe the sand would take the path of least resistance and fall to the sides of the column rather than telescope it into itself. Of course, I could always be wrong.

I was thinking about this same thing. I wonder if the towers were built with a slight inward taper of some sort? They looked to be perfectly square, but maybe that's an optical illusion. Maybe the top of the toweres were a slightly smaller dimension that the bottom footprint. This would explain how the mass from above would fit just slight inside the structure below, blowing out everything from the inside out on the way down.

Or alternatively, for WTC2, the tilt of the top of the tower would take care of this problem. It tilted far more than enough to drop down onto the lower floors, pummeling anything in its way.

WTC1 is a different matter. Was there any tilt noticed in WTC1 before the collapse? Even a slight tilt may have been enough to have the columns slide inside the supporting columns.

WTC7 is a totally different situation. The entire perimeter support columns failed simultaneously from the bottom. What would make every perimeter column fail at the bottom of the building at the same time? Until somebody can explain how this logically could have happened from gouging to the south face, and south west corner, there's no other explanation imo other than a demolition of some sort.