QUOTE (adoucette+Aug 10 2007, 01:32 AM)
You're right, there is NOTHING NEW here.
Its FRIGGIN OBVIOUS how the fuel made it to the basement.
Again:
http://i117.photobucket.com/albums/o72/ard...levators-3d.jpg
So what do you mean ASIDE FROM THE FEW ELEVATORS that spanned the entire floors?
As the graphic shows they are all co-located.
And as the LAST graphic of the floor layout shows those large Express Elevators are HUGE, and NO they DIDN'T have walls between ADJACENT shafts.
What ELSE do you need to get fuel all the way to the basement?
Also notice the tops of the Shafts on the Express Elevators to the Upper lobby.
Notice they are OPEN.
Notice they GO PAST the mechanical floors.
Notice they run all the way to the bottom floors.
You don't think of the THOUSANDS of gallons of fuel from the plane that possibly hundreds of gallons might not have made it to THOSE open shafts?
Say after a few minutes?
Arthur
It's a theory. Let us know when you get some peer reviewed papers to back it up - perhaps you can get the Purdue team to model exactly how much fuel would make it to the basement. Personally, I don't buy it: too many 90 degree turns, too much fuel being burned up in the fires at the top. Don't forget also that the stairwells below the impact floors were clear and allowed hundreds of people to escape.
But by all means, please share any peer reviewed papers that back up your position; let's start applying the same standards to both sides of the argument. This forum is fast turning into speculation central for whacked out ideas from the OCT crew. With a bonus bad attitude to mask the lack of substance.
Its FRIGGIN OBVIOUS how the fuel made it to the basement.
Again:
http://i117.photobucket.com/albums/o72/ard...levators-3d.jpg
So what do you mean ASIDE FROM THE FEW ELEVATORS that spanned the entire floors?
As the graphic shows they are all co-located.
And as the LAST graphic of the floor layout shows those large Express Elevators are HUGE, and NO they DIDN'T have walls between ADJACENT shafts.
What ELSE do you need to get fuel all the way to the basement?
Also notice the tops of the Shafts on the Express Elevators to the Upper lobby.
Notice they are OPEN.
Notice they GO PAST the mechanical floors.
Notice they run all the way to the bottom floors.
You don't think of the THOUSANDS of gallons of fuel from the plane that possibly hundreds of gallons might not have made it to THOSE open shafts?
Say after a few minutes?
Arthur
It's a theory. Let us know when you get some peer reviewed papers to back it up - perhaps you can get the Purdue team to model exactly how much fuel would make it to the basement. Personally, I don't buy it: too many 90 degree turns, too much fuel being burned up in the fires at the top. Don't forget also that the stairwells below the impact floors were clear and allowed hundreds of people to escape.
But by all means, please share any peer reviewed papers that back up your position; let's start applying the same standards to both sides of the argument. This forum is fast turning into speculation central for whacked out ideas from the OCT crew. With a bonus bad attitude to mask the lack of substance.
QUOTE
Personally, I don't buy it: too many 90 degree turns
Maybe the reason you think there are so many 90 degree turns is because you still haven't figured out the difference between your schematic and the actual elevator layouts that Arthur has provided.
Schematics are intended to convey CONCEPTS, not the literal truth.
And you need a paper to help you understanding why a liquid would fall down a shaft?!?
QUOTE (adoucette+Aug 10 2007, 01:32 AM)
Also notice the tops of the Shafts on the Express Elevators to the Upper lobby.
Notice they are OPEN.
Notice they GO PAST the mechanical floors.
Notice they run all the way to the bottom floors.
You don't think of the THOUSANDS of gallons of fuel from the plane that possibly hundreds of gallons might not have made it to THOSE open shafts?
Say after a few minutes?
Arthur
yeah, i guess. it's pretty easy for kerosene to sneak past open flame.
oh, yeah, and 'OPEN'? what lifts the elevator up? a gigantic hydraulic cylinder underneath, or a cable on a winch above?
you say something goes PAST the mechanical floors, but the NIST says that the space over elevator shafts on the mechanical floors was concreted over and 'for rent'.
[insult]_________[/insult]
QUOTE (wcelliott+Aug 10 2007, 02:36 AM)
Maybe the reason you think there are so many 90 degree turns is because you still haven't figured out the difference between your schematic and the actual elevator layouts that Arthur has provided.
Schematics are intended to convey CONCEPTS, not the literal truth.
And you need a paper to help you understanding why a liquid would fall down a shaft?!?
well, the fuel's trajectory was horizontal, and gravity is vertical. i'm not an engineer looking at a drawing, but i think that's 90°.
tell arthur about schematics, too. he seems to think elevators float up, and the tops of the shafts are open.
QUOTE (newton+Aug 10 2007, 02:42 AM)
yeah, i guess. it's pretty easy for kerosene to sneak past open flame.
oh, yeah, and 'OPEN'? what lifts the elevator up? a gigantic hydraulic cylinder underneath, or a cable on a winch above?
you say something goes PAST the mechanical floors, but the NIST says that the space over elevator shafts on the mechanical floors was concreted over and 'for rent'.
[insult]_________[/insult]
The shaft seals were not designed to contain a fuel air blast, they were not concreted over but sealed mechanically.
As were the utility shafts but access to those systems has to have been available some how. The very weight of the fuel could over come the shaft seals as they were not designed for those conditions.
Please give your calculations that show that fuel air explosions do not produce shock waves and heat, that would have caused liquid Fuel to travel down elevator shafts consuming the oxygen in those as it fell.
Please show that intense Chemical reactions can not take place in the shafts!
IT all comes down in the end to gravity and the fuel taking the path of least resistance.
PS. The carbon black on the stairs proves there was fuel though-out the buildings, where else did it come from if not from below?
The firefighters testimony is one hundred percent in favor of fuel air blasts and unless you can find that there is some undisclosed mechanism, then you have to assume the likely hood that the explosions are the result of fuel air blasts.
Your own a physics forum Newton please learn some simple physics before commenting more, it makes everyone on here look bad to be associated with someone with such a basic lack of knowledge.
oh, yeah, and 'OPEN'? what lifts the elevator up? a gigantic hydraulic cylinder underneath, or a cable on a winch above?
you say something goes PAST the mechanical floors, but the NIST says that the space over elevator shafts on the mechanical floors was concreted over and 'for rent'.
[insult]_________[/insult]
The shaft seals were not designed to contain a fuel air blast, they were not concreted over but sealed mechanically.
As were the utility shafts but access to those systems has to have been available some how. The very weight of the fuel could over come the shaft seals as they were not designed for those conditions.
Please give your calculations that show that fuel air explosions do not produce shock waves and heat, that would have caused liquid Fuel to travel down elevator shafts consuming the oxygen in those as it fell.
Please show that intense Chemical reactions can not take place in the shafts!
IT all comes down in the end to gravity and the fuel taking the path of least resistance.
PS. The carbon black on the stairs proves there was fuel though-out the buildings, where else did it come from if not from below?
The firefighters testimony is one hundred percent in favor of fuel air blasts and unless you can find that there is some undisclosed mechanism, then you have to assume the likely hood that the explosions are the result of fuel air blasts.
Your own a physics forum Newton please learn some simple physics before commenting more, it makes everyone on here look bad to be associated with someone with such a basic lack of knowledge.
QUOTE
well, the fuel's trajectory was horizontal,
No, it WASN'T. That's the whole point!
It *would've* been horizontal if they'd laid-out the elevator shafts like you and Lozenge seem to think they were laid-out, based on your COLLECTIVE IGNORANCE about what a SCHEMATIC is, but as I've said THREE TIMES now, a SCHEMATIC is an ILLUSTRATION OF A CONCEPT, NOT a representation of the literal TRUTH.
Lozenge provided two SCHEMATICS illustrating the CONCEPT of the elevators in the WTC, but THAT WASN'T HOW THE ELEVATORS WERE LAID-OUT.
The various shafts were colocated in the core, and stacked one atop the other, not laid-out side-by-side like Lozenge's SCHEMATIC showed.
YEESH!!!
Buy a clue!
QUOTE (newton+Aug 10 2007, 03:08 AM)
well, the fuel's trajectory was horizontal, and gravity is vertical. i'm not an engineer looking at a drawing, but i think that's 90°.
tell arthur about schematics, too. he seems to think elevators float up, and the tops of the shafts are open.
The top of the shafts is where the winch and cable are no open shaft no way for the cable to go down.
A light metal shield is generally all that seals the shafts.
Did you think that a big gust of hot air from Godzilla was used to propel the elevators upward?
tell arthur about schematics, too. he seems to think elevators float up, and the tops of the shafts are open.
The top of the shafts is where the winch and cable are no open shaft no way for the cable to go down.
A light metal shield is generally all that seals the shafts.
Did you think that a big gust of hot air from Godzilla was used to propel the elevators upward?
QUOTE (lozenge124+Aug 9 2007, 10:07 PM)
It's a theory. Let us know when you get some peer reviewed papers to back it up - perhaps you can get the Purdue team to model exactly how much fuel would make it to the basement. Personally, I don't buy it: too many 90 degree turns, too much fuel being burned up in the fires at the top. Don't forget also that the stairwells below the impact floors were clear and allowed hundreds of people to escape.
But by all means, please share any peer reviewed papers that back up your position; let's start applying the same standards to both sides of the argument. This forum is fast turning into speculation central for whacked out ideas from the OCT crew. With a bonus bad attitude to mask the lack of substance.
No one is going to do a paper on something that is friggin obvious and that NIST documented so well.
Pay attention.
Please See Fig A-1 in NIST NCSTAR 1-5F, the floor plan of the 92nd floor.
50 is the Freight elevator.
Its shaft runs to the basement.
6 & 7 are the Express elevators.
Their shafts run to the basement.
Now go to Fig A-9 see what the 78th floor looked like.
See how the numbering systems agree with this:
http://i117.photobucket.com/albums/o72/ard...WTC9712Fi10.gif
Note that the Elevators here. `12, 13, 14, 15 and 20, 21, 22, 23 are the 8 huge express elevators that go all the way to the lobby.
Note that the Mechanical floors are BELOW the 78th floor.
BECAUSE THE EXPRESS ELEVATORS, go past the mechanical floors so they OVERLAP with the NEXT set of LOCAL Elevators.
So there is NO major structural barrier between these shafts and the impact zone.
In fact there is quite a bit of DUCTING between them.
Note the gray boxes with the Xs in them.
They are the air ducts.
The run all the way to the impact zone.
The plane hit on the "100" side.
The fuel arrived like high pressure spray, the vast majority of it unburnt when it got to the elevator shafts in LESS THAN 1/3 of a second, and was moving at several hundred miles per hour at the time. It was distributed over 8 floors.
See NIST NCSTAR 1-2B fig 3-17
See NIST NCSTAR 1-2 Fig 7-19
See NIST NCSTAR 1-2 Table 7-2 for the multi floor distribution of the fuel.
Arthur
But by all means, please share any peer reviewed papers that back up your position; let's start applying the same standards to both sides of the argument. This forum is fast turning into speculation central for whacked out ideas from the OCT crew. With a bonus bad attitude to mask the lack of substance.
No one is going to do a paper on something that is friggin obvious and that NIST documented so well.
Pay attention.
Please See Fig A-1 in NIST NCSTAR 1-5F, the floor plan of the 92nd floor.
50 is the Freight elevator.
Its shaft runs to the basement.
6 & 7 are the Express elevators.
Their shafts run to the basement.
Now go to Fig A-9 see what the 78th floor looked like.
See how the numbering systems agree with this:
http://i117.photobucket.com/albums/o72/ard...WTC9712Fi10.gif
Note that the Elevators here. `12, 13, 14, 15 and 20, 21, 22, 23 are the 8 huge express elevators that go all the way to the lobby.
Note that the Mechanical floors are BELOW the 78th floor.
BECAUSE THE EXPRESS ELEVATORS, go past the mechanical floors so they OVERLAP with the NEXT set of LOCAL Elevators.
So there is NO major structural barrier between these shafts and the impact zone.
In fact there is quite a bit of DUCTING between them.
Note the gray boxes with the Xs in them.
They are the air ducts.
The run all the way to the impact zone.
The plane hit on the "100" side.
The fuel arrived like high pressure spray, the vast majority of it unburnt when it got to the elevator shafts in LESS THAN 1/3 of a second, and was moving at several hundred miles per hour at the time. It was distributed over 8 floors.
See NIST NCSTAR 1-2B fig 3-17
See NIST NCSTAR 1-2 Fig 7-19
See NIST NCSTAR 1-2 Table 7-2 for the multi floor distribution of the fuel.
Arthur
QUOTE (newton+Aug 9 2007, 10:42 PM)
you say something goes PAST the mechanical floors, but the NIST says that the space over elevator shafts on the mechanical floors was concreted over and 'for rent'.
NIST said the area over the elevators was concreted over and it was, over local banks N O P J K L F G & H.
But Express elevator banks B, C and D went PAST the mechanical floors and thus OVERLAP with their respective local elevators, before they are concreted over.
Its EASILY seen in this schematic.
http://i117.photobucket.com/albums/o72/ard...WTC9712Fi10.gif
Though you may have to load it into a viewer to be able to read the small print.
The top of the elevator shafts was a two story area that contained the lift equipment, but the elevator shaft itself would not be sealed, you couldn't raise a 10,000 lb 1,600 fpm express elevator in a SEALED shaft and not have SOMETHING give.
Arthur
NIST said the area over the elevators was concreted over and it was, over local banks N O P J K L F G & H.
But Express elevator banks B, C and D went PAST the mechanical floors and thus OVERLAP with their respective local elevators, before they are concreted over.
Its EASILY seen in this schematic.
http://i117.photobucket.com/albums/o72/ard...WTC9712Fi10.gif
Though you may have to load it into a viewer to be able to read the small print.
The top of the elevator shafts was a two story area that contained the lift equipment, but the elevator shaft itself would not be sealed, you couldn't raise a 10,000 lb 1,600 fpm express elevator in a SEALED shaft and not have SOMETHING give.
Arthur
QUOTE (wcelliott+Aug 10 2007, 03:27 AM)
No, it WASN'T. That's the whole point!
It *would've* been horizontal if they'd laid-out the elevator shafts like you and Lozenge seem to think they were laid-out, based on your COLLECTIVE IGNORANCE about what a SCHEMATIC is, but as I've said THREE TIMES now, a SCHEMATIC is an ILLUSTRATION OF A CONCEPT, NOT a representation of the literal TRUTH.
Lozenge provided two SCHEMATICS illustrating the CONCEPT of the elevators in the WTC, but THAT WASN'T HOW THE ELEVATORS WERE LAID-OUT.
The various shafts were colocated in the core, and stacked one atop the other, not laid-out side-by-side like Lozenge's SCHEMATIC showed.
YEESH!!!
Buy a clue!
so, your new theory is that the planes came from directly above?
sorry.
fuel(like plane, duh) - horizontal
shafts and gravity - vertical
i guess that COULD be 270°, depending on which way you look at it. i like 90°, though.
QUOTE
fuel(like plane, duh) - horizontal
shafts and gravity - vertical
shafts and gravity - vertical
So, you figure once something's going horizontally, it can't fall down?
The answer to the "Evil versus Stupid" question is clearly now "Both".
QUOTE (wcelliott+Aug 10 2007, 05:06 AM)
So, you figure once something's going horizontally, it can't fall down?
The answer to the "Evil versus Stupid" question is clearly now "Both".
He has forgotten that the fuel like the plane hit a building, and the inside of a building and rebounds in all directions, I have seen two year olds with more knowledge of physics and how impacts effect fluids.
There was this one little girl at rough river lake when I was up there that would not get wet she took a little bucket, and scooped up some water, and then splashed the water on a rock. She knew enough to step back, as she knew the fluid would rebound back at her.
Same thing occurs in the towers the fluid- fuel goes anywhere it can.
The little girls mother said she liked to splash water, but hates to get wet, she knew enough at that age to not let the water splash on her. She would make a good physicist a lot better than our Newton.
Newton it is all about action=Reaction in a causal universe.
QUOTE (wcelliott+Aug 10 2007, 01:06 AM)
So, you figure once something's going horizontally, it can't fall down?
The answer to the "Evil versus Stupid" question is clearly now "Both".
If you want to see the impact angle of the plane see NIST NCSTAR 1-2B Fig E-24
The plane was on a downward angle ~ 10 deg below horizontal, and distributed fuel over 8 floors, including floors ABOVE where it hit.
I still wonder what newton thinks happens when fluid racing over a horizontal surface hits an open vertical shaft.
Arthur
QUOTE (David B. Benson+Jul 31 2007, 11:26 PM)
If you are referring to the escaping air from the ventilators on the mechanical floors of WTC 2, NEU-FONZE some time ago commented that the flow rate was the same as the descent rate of the crushed mass above.
The same idea works for the others. The mathematics is quite straightforward and I posted it somewhere in the first 150 pages of the previous thread.
By "squib", I mean what Kevin Ryan referred to in his paper - air and debris being ejected outside the building, well below (40 floors worth, in one case, IIRC) the collapse front.
The only OCT notion to "explain" this that sounds even slightly plausible is an explosion of previously un-ignited jet fuel. And as to how plausible this theory is, I'd say "not very".
I haven't studied NEU-FONZE's posts on the squibs, or your own, but if they suggest that a collapse front 40 floor away is compressing air through a ventilation channel, such that air is being forced out the lower end, at the same speed as the collapse front, and that this air then pick up debris and hurls it through windows, also at this speed, and that this occurs, in some cases, on multiple floors, then I think that's ludicrous.
Telll me that's not what's being suggested.
BTW, a poster at JREF (I think the Mackay(sp?) guy) has run some numbers (apparently after researching equations describing explosions) which suggest speed differentials according to size of ejecta. Such considerations probably would shed light on the squibs.
In Mackay's post, though, he shows no calculations, nor does he clearly show his assumptions, nor give references.
Also, his logic seems spurious, as he (apparently) assumes a single demolition agent, as well as point of origin for the various-sized debris. I think he views cutter charges as simply freeing metal parts of the structure, as opposed to simultaneously freeing them and imparting momentum.
However, if I understand one of his basic points, I think he's actually undercut his argument, certainly in the case of the squibs. And that's because an undifferentiated squib field (by which I mean, various sized debris do not appear to have significant variations in horizontal displacement) implies a nearby point source of explosion
QUOTE (metamars+Aug 10 2007, 02:08 PM)
By "squib", I mean what Kevin Ryan referred to in his paper - air and debris being ejected outside the building, well below (40 floors worth, in one case, IIRC) the collapse front.
The only OCT notion to "explain" this that sounds even slightly plausible is an explosion of previously un-ignited jet fuel. And as to how plausible this theory is, I'd say "not very".
I haven't studied NEU-FONZE's posts on the squibs, or your own, but if they suggest that a collapse front 40 floor away is compressing air through a ventilation channel, such that air is being forced out the lower end, at the same speed as the collapse front, and that this air then pick up debris and hurls it through windows, also at this speed, and that this occurs, in some cases, on multiple floors, then I think that's ludicrous.
Telll me that's not what's being suggested.
BTW, a poster at JREF (I think the Mackay(sp?) guy) has run some numbers (apparently after researching equations describing explosions) which suggest speed differentials according to size of ejecta. Such considerations probably would shed light on the squibs.
In Mackay's post, though, he shows no calculations, nor does he clearly show his assumptions, nor give references.
Also, his logic seems spurious, as he (apparently) assumes a single demolition agent, as well as point of origin for the various-sized debris. I think he views cutter charges as simply freeing metal parts of the structure, as opposed to simultaneously freeing them and imparting momentum.
However, if I understand one of his basic points, I think he's actually undercut his argument, certainly in the case of the squibs. And that's because an undifferentiated squib field (by which I mean, various sized debris do not appear to have significant variations in horizontal displacement) implies a nearby point source of explosion
Look up coal dust explosions carbon black in the fire fighters account of it being on the stairs turning the stairs black can be explosive, all you have to do is have it mix with air and ignite, I have even made crude iron with the left over carbon black from Diesel exhaust systems.
A suspended dust explosion in the collapse is highly likely to occur, because of the collapse shaking the structures below it jet fuel is hardly the only fuel source in that building.
It was very crude iron, and it still contains a bunch of Fe203 which is why it still has a rusty hue.
The Mechanical energy generated in the collapse can cause other reactions ignoring that fact Ignores reality.
The only OCT notion to "explain" this that sounds even slightly plausible is an explosion of previously un-ignited jet fuel. And as to how plausible this theory is, I'd say "not very".
I haven't studied NEU-FONZE's posts on the squibs, or your own, but if they suggest that a collapse front 40 floor away is compressing air through a ventilation channel, such that air is being forced out the lower end, at the same speed as the collapse front, and that this air then pick up debris and hurls it through windows, also at this speed, and that this occurs, in some cases, on multiple floors, then I think that's ludicrous.
Telll me that's not what's being suggested.
BTW, a poster at JREF (I think the Mackay(sp?) guy) has run some numbers (apparently after researching equations describing explosions) which suggest speed differentials according to size of ejecta. Such considerations probably would shed light on the squibs.
In Mackay's post, though, he shows no calculations, nor does he clearly show his assumptions, nor give references.
Also, his logic seems spurious, as he (apparently) assumes a single demolition agent, as well as point of origin for the various-sized debris. I think he views cutter charges as simply freeing metal parts of the structure, as opposed to simultaneously freeing them and imparting momentum.
However, if I understand one of his basic points, I think he's actually undercut his argument, certainly in the case of the squibs. And that's because an undifferentiated squib field (by which I mean, various sized debris do not appear to have significant variations in horizontal displacement) implies a nearby point source of explosion
Look up coal dust explosions carbon black in the fire fighters account of it being on the stairs turning the stairs black can be explosive, all you have to do is have it mix with air and ignite, I have even made crude iron with the left over carbon black from Diesel exhaust systems.
A suspended dust explosion in the collapse is highly likely to occur, because of the collapse shaking the structures below it jet fuel is hardly the only fuel source in that building.
It was very crude iron, and it still contains a bunch of Fe203 which is why it still has a rusty hue.
The Mechanical energy generated in the collapse can cause other reactions ignoring that fact Ignores reality.
QUOTE (metamars+Aug 10 2007, 10:08 AM)
By "squib", I mean what Kevin Ryan referred to in his paper - air and debris being ejected outside the building, well below (40 floors worth, in one case, IIRC) the collapse front.
The only OCT notion to "explain" this that sounds even slightly plausible is an explosion of previously un-ignited jet fuel. And as to how plausible this theory is, I'd say "not very".
But the CT'ers have NOT shown that these "squibs" need to be explained.
What IS clear is they don't occur until well after the building IS collapsing.
Because we KNOW the building is collapsing SLOWER than gravity and we KNOW there are large shafts running down the building, but with floors to those shafts at different levels, we KNOW that things can OUTRUN the collapse and then impact floors at great speeds.
Thus, even without knowing EXACTLY what caused the "squibs" the most likely source is energy being released in the collapse as opposed to something which is hastening the collapse.
Further, we KNOW, based on the damage done by the previous bombing at the WTC, that failed to sever even ONE column, that a bomb sufficient to do any significant damage to the towers would NOT look like those pathetic "squibs".
So the ball REMAINS in the CT'er court to explain precisely why anyone should give a damn about those puffs of air and debris.
Arthur
The only OCT notion to "explain" this that sounds even slightly plausible is an explosion of previously un-ignited jet fuel. And as to how plausible this theory is, I'd say "not very".
But the CT'ers have NOT shown that these "squibs" need to be explained.
What IS clear is they don't occur until well after the building IS collapsing.
Because we KNOW the building is collapsing SLOWER than gravity and we KNOW there are large shafts running down the building, but with floors to those shafts at different levels, we KNOW that things can OUTRUN the collapse and then impact floors at great speeds.
Thus, even without knowing EXACTLY what caused the "squibs" the most likely source is energy being released in the collapse as opposed to something which is hastening the collapse.
Further, we KNOW, based on the damage done by the previous bombing at the WTC, that failed to sever even ONE column, that a bomb sufficient to do any significant damage to the towers would NOT look like those pathetic "squibs".
So the ball REMAINS in the CT'er court to explain precisely why anyone should give a damn about those puffs of air and debris.
Arthur
metamars
You're not paying much attention to what we are actually saying, are you??? The "squibs" are simply the air displaced by the pancaking floors/debris, which outpaced the outer frame collapse by various amounts in both buildings. No one here has claimed the "squibs" were the result of F/A explosives, those were happening in the core(mainly in the confining elevator shafts) and were mainly visible by their effects on the elevators(blown out) and people within them(burns) and the lobby's and subbasement's destruction. This makes much more sense than invisible, ninja thermite fairies.
The floor pancaking was initiated by the frame collapse, but with no ejection of mass it was a cumulative process that accelerated faster than the top block dropped(with it's mass ejections), the only VISIBLE indication of this process was the "squibs". But further evidence of it's action is in the vertical stripping of the floor supports(which had to occur while the frames were still upright) and the fact that all of the contents of the floors below the impact zones were found in strata in the basements AND NOWHERE ELSE( this means the outer frame had to be intact to funnel that debris). So the entire process of the floor collapse was over by the time the top block reached that particular outer frame member. It can be argued about how far ahead the collapsing floors were, but the evidence makes it certain that it preceded the top block collapse zone, and I would argue that it preceded it by multiple floors, especially in 1.
Grumpy
QUOTE
The only OCT notion to "explain" this that sounds even slightly plausible is an explosion of previously un-ignited jet fuel. And as to how plausible this theory is, I'd say "not very".
You're not paying much attention to what we are actually saying, are you??? The "squibs" are simply the air displaced by the pancaking floors/debris, which outpaced the outer frame collapse by various amounts in both buildings. No one here has claimed the "squibs" were the result of F/A explosives, those were happening in the core(mainly in the confining elevator shafts) and were mainly visible by their effects on the elevators(blown out) and people within them(burns) and the lobby's and subbasement's destruction. This makes much more sense than invisible, ninja thermite fairies.
The floor pancaking was initiated by the frame collapse, but with no ejection of mass it was a cumulative process that accelerated faster than the top block dropped(with it's mass ejections), the only VISIBLE indication of this process was the "squibs". But further evidence of it's action is in the vertical stripping of the floor supports(which had to occur while the frames were still upright) and the fact that all of the contents of the floors below the impact zones were found in strata in the basements AND NOWHERE ELSE( this means the outer frame had to be intact to funnel that debris). So the entire process of the floor collapse was over by the time the top block reached that particular outer frame member. It can be argued about how far ahead the collapsing floors were, but the evidence makes it certain that it preceded the top block collapse zone, and I would argue that it preceded it by multiple floors, especially in 1.
Grumpy
QUOTE (adoucette+Aug 10 2007, 04:44 PM)
Because we KNOW the building is collapsing SLOWER than gravity and we KNOW there are large shafts running down the building, but with floors to those shafts at different levels, we KNOW that things can OUTRUN the collapse and then impact floors at great speeds.
I'm not going to bother looking up how quickly air pressure can equilibrate in any plausible WTC scenario, but intuitively it's so rapid, "explanations" about "OUTRUN"ning a collapse front strike me as preposterous.
Why don't you put this question to your OCT fellow travelers that some experience with physics? I'd be surprised if they can do anything more than wave their hands in support of such a notion, though.
QUOTE
Further, we KNOW, based on the damage done by the previous bombing at the WTC, that failed to sever even ONE column, that a bomb sufficient to do any significant damage to the towers would NOT look like those pathetic "squibs".
Considering how similar WTC squibs are to non-WTC squibs, I find this strawman particularly disingenuous.
QUOTE (->
| QUOTE |
Further, we KNOW, based on the damage done by the previous bombing at the WTC, that failed to sever even ONE column, that a bomb sufficient to do any significant damage to the towers would NOT look like those pathetic "squibs". |
Considering how similar WTC squibs are to non-WTC squibs, I find this strawman particularly disingenuous.
So the ball REMAINS in the CT'er court to explain precisely why anyone should give a damn about those puffs of air and debris.
Arthur
As Bob Dylan might have said, had he been born more recently,
the answer, my friend
is blowing in the squib
the answer is blowing in the squib
QUOTE (metamars+Aug 10 2007, 07:08 AM)
... then I think that's ludicrous.
About 7% of the area of each floor was voids in the core. Check it in NCSTAR1--2A.
The air must escape somehow. The voids will suffice along with the windows. Whatever portion escapes through the voids over-pressurizes the lower portion of the tower. For this there is direct evidence:
(1) A survivor reported being blown down six flights of stairs. As a survivor, he had to run over to WTC 6, or else survive in the so-called lunar module, so he could not have been very far up as the collapse started. (I take this a quite a substantial over-pressurization quite far down, at least in the stairwells.
(2) A non-survivor took a photograph of dusty air being blown out of the lobby and several stories further up (glass was long gone). While there is no way to determine where the collapse front was, it at least was higher than anything visible in the photograph.
So I have no difficulty whatsoever with the air being blown out the ventilators at the mechanical floors. The air shafts above lead directly through the air handling equipment to these ventilators. The air being compressed just above blows out here.
Slightly more problematic is the smaller puffs further below the collapse front. I've read claims of 30, 40 and 50 floors below. Since there are only a couple of these, we can be quite sure that the lower portion of the tower was not over-pressurized to one psi, since that ought to be enough to break the glass and that event occurred only rarely. However, the initial shock to the tower of the airplane impact could well have cracked or broken the quarter inch plate glass in a few places about the structure. These, then, provided egress for the dusty air.
About 7% of the area of each floor was voids in the core. Check it in NCSTAR1--2A.
The air must escape somehow. The voids will suffice along with the windows. Whatever portion escapes through the voids over-pressurizes the lower portion of the tower. For this there is direct evidence:
(1) A survivor reported being blown down six flights of stairs. As a survivor, he had to run over to WTC 6, or else survive in the so-called lunar module, so he could not have been very far up as the collapse started. (I take this a quite a substantial over-pressurization quite far down, at least in the stairwells.
(2) A non-survivor took a photograph of dusty air being blown out of the lobby and several stories further up (glass was long gone). While there is no way to determine where the collapse front was, it at least was higher than anything visible in the photograph.
So I have no difficulty whatsoever with the air being blown out the ventilators at the mechanical floors. The air shafts above lead directly through the air handling equipment to these ventilators. The air being compressed just above blows out here.
Slightly more problematic is the smaller puffs further below the collapse front. I've read claims of 30, 40 and 50 floors below. Since there are only a couple of these, we can be quite sure that the lower portion of the tower was not over-pressurized to one psi, since that ought to be enough to break the glass and that event occurred only rarely. However, the initial shock to the tower of the airplane impact could well have cracked or broken the quarter inch plate glass in a few places about the structure. These, then, provided egress for the dusty air.
QUOTE (metamars+Aug 10 2007, 05:19 PM)
the answer, my friend
is blowing in the squib
the answer is blowing in the squib
But its NOT a SQUIB.
Its an explulsion of air and debris.
You can't call it a SQUIB unless you can PROVE that it is a Squib.
Which the CT'ers have UTTERLY failed to do.
The SIMPLE explanation is that it is an expulsion created by the physical events related to the towers collapse.
So even though there are multiple SIMPLE explanations, CTers go for the extremely UNLIKELY suggestion simply because it agrees with what their PRE-DETERMINED conclusion demands.
The CT'er method of picking on ANYTHING that is not easily explainable and then TWISTING that to somehow be EVIDENCE of something is pathetic.
Clearly the mark of DESPERATE people.
Arthur
is blowing in the squib
the answer is blowing in the squib
But its NOT a SQUIB.
Its an explulsion of air and debris.
You can't call it a SQUIB unless you can PROVE that it is a Squib.
Which the CT'ers have UTTERLY failed to do.
The SIMPLE explanation is that it is an expulsion created by the physical events related to the towers collapse.
So even though there are multiple SIMPLE explanations, CTers go for the extremely UNLIKELY suggestion simply because it agrees with what their PRE-DETERMINED conclusion demands.
The CT'er method of picking on ANYTHING that is not easily explainable and then TWISTING that to somehow be EVIDENCE of something is pathetic.
Clearly the mark of DESPERATE people.
Arthur
metamars
Let's see if I've got this straight, Puffs of air out of the windows of a collapsing building are preposterous, but non-nuclear(clean) mini-nukes are not??? Buildings collapsing due to plane impacts and fire is preposterous, but invisible, ninja thermite fairies are not??? Fuel/air explosions and fuel down the elevator shafts in a building that was splashed with 50 TONS of fuel are preposterous, but some nefarious agency(read INTFs)planting "squibs" undetected prior to the event is not???
Personally I think your BS meter is in dire need of recalibration(either that or you've got it hooked up with the polarity reversed).
Grumpy
QUOTE
I'm not going to bother looking up how quickly air pressure can equilibrate in any plausible WTC scenario, but intuitively it's so rapid, "explanations" about "OUTRUN"ning a collapse front strike me as preposterous.
Let's see if I've got this straight, Puffs of air out of the windows of a collapsing building are preposterous, but non-nuclear(clean) mini-nukes are not??? Buildings collapsing due to plane impacts and fire is preposterous, but invisible, ninja thermite fairies are not??? Fuel/air explosions and fuel down the elevator shafts in a building that was splashed with 50 TONS of fuel are preposterous, but some nefarious agency(read INTFs)planting "squibs" undetected prior to the event is not???
Personally I think your BS meter is in dire need of recalibration(either that or you've got it hooked up with the polarity reversed).
Grumpy
QUOTE (Grumpy+Aug 10 2007, 04:08 PM)
... you've got it hooked up with the polarity reversed.
QUOTE (David B. Benson+Aug 10 2007, 09:22 PM)
About 7% of the area of each floor was voids in the core. Check it in NCSTAR1--2A.
And I would expect that the area of the collapse front, over the voids in the core, but within the footprint of the buildings, is also 7%. Your point is? This suggests a pressure differential between core voids and core non-voids. Also, I suppose, you're suggesting a pressure differential between the core voids and non-core. However, as we have heard, again and again, that the WTC towers were mostly "empty space", what are you claiming that this pressure differential amounts to?
QUOTE
The air must escape somehow. The voids will suffice along with the windows. Whatever portion escapes through the voids over-pressurizes the lower portion of the tower. For this there is direct evidence:
(1) A survivor reported being blown down six flights of stairs. As a survivor, he had to run over to WTC 6, or else survive in the so-called lunar module, so he could not have been very far up as the collapse started. (I take this a quite a substantial over-pressurization quite far down, at least in the stairwells.
And somebody else (like myself) could take it as evidence of explosions, especially if (as I would expect) a serious analysis shows that any plausible gravity driven scenario would not have created any sort of wind such as you seem to imply.
Furthermore, due to the rapid rate that air pressure will equilibrate, why would not an advancing front result in a steadily increasing air pressure, rather than some sort of mysterious, squib-producing down draft?
Also, blown "down" through 6 flights of stairs is difficult to take literally. Most stairs that I've ever been in wrap around every floor. If this guy started to take a fall, he would soon have crashed against a wall, where the stairs makes a right angle turn. The implication is that the "wind" was so violent that he not only fell, but after smashing him against the wall, carried him off to the side and down again.
What sort of wind velocity does that imply? I'd guess at least a hurricane-strength wind (>74 mph). Considering the obesity epidemic in America, that guess may be way too low.* It also raises questions about how he survived, with enough intact bones to escape the building.
Actually, though, I'm glad you wrote this since:
QUOTE (->
| QUOTE |
The air must escape somehow. The voids will suffice along with the windows. Whatever portion escapes through the voids over-pressurizes the lower portion of the tower. For this there is direct evidence: (1) A survivor reported being blown down six flights of stairs. As a survivor, he had to run over to WTC 6, or else survive in the so-called lunar module, so he could not have been very far up as the collapse started. (I take this a quite a substantial over-pressurization quite far down, at least in the stairwells. |
And somebody else (like myself) could take it as evidence of explosions, especially if (as I would expect) a serious analysis shows that any plausible gravity driven scenario would not have created any sort of wind such as you seem to imply.
Furthermore, due to the rapid rate that air pressure will equilibrate, why would not an advancing front result in a steadily increasing air pressure, rather than some sort of mysterious, squib-producing down draft?
Also, blown "down" through 6 flights of stairs is difficult to take literally. Most stairs that I've ever been in wrap around every floor. If this guy started to take a fall, he would soon have crashed against a wall, where the stairs makes a right angle turn. The implication is that the "wind" was so violent that he not only fell, but after smashing him against the wall, carried him off to the side and down again.
What sort of wind velocity does that imply? I'd guess at least a hurricane-strength wind (>74 mph). Considering the obesity epidemic in America, that guess may be way too low.* It also raises questions about how he survived, with enough intact bones to escape the building.
Actually, though, I'm glad you wrote this since:
(2) A non-survivor took a photograph of dusty air being blown out of the lobby and several stories further up (glass was long gone). While there is no way to determine where the collapse front was, it at least was higher than anything visible in the photograph.
If the "glass was long gone", that may suggest a reason for some of the explosions. Blown glass in lower floors might allow a 'draft' through the building, as it collapses, which might make for a tidier CD (as such a 'safety valve' would mean less over-pressure throughout the building, which means fewer windows breaking before the collapse front reaches them.) Such 'tidiness' would not be desirable ito after the collapse/CD was completed, but rather while it was occurring. Too much air pressure, and there might have rings of outwardly exploding windows preceding the collapse front, all the way down (but not with debris). One doesn't want to make CD obvious, unless, of course, as in the case of WTC 7, one has the power and intention to keep it off of the evening news.
QUOTE
So I have no difficulty whatsoever with the air being blown out the ventilators at the mechanical floors. The air shafts above lead directly through the air handling equipment to these ventilators. The air being compressed just above blows out here.
You are using observations, which themselves are problematic ito a gravity driven scenario, to "explain" yet another observation which is problematic ito of gravity driven collapse. Since the basic task to to decide between competing hypotheses, using physics (where possible), I fail to see where you have advanced your argument.
If you want to do so, you should, e.g., demonstrate why a gravity driven collapse can blow a man not only down, but around 6 flights of stairs. Otherwise, you are basically restating the problem, not solving it.
And how can you do this without recourse to some fluid dynamics?
QUOTE (->
| QUOTE |
So I have no difficulty whatsoever with the air being blown out the ventilators at the mechanical floors. The air shafts above lead directly through the air handling equipment to these ventilators. The air being compressed just above blows out here. |
You are using observations, which themselves are problematic ito a gravity driven scenario, to "explain" yet another observation which is problematic ito of gravity driven collapse. Since the basic task to to decide between competing hypotheses, using physics (where possible), I fail to see where you have advanced your argument.
If you want to do so, you should, e.g., demonstrate why a gravity driven collapse can blow a man not only down, but around 6 flights of stairs. Otherwise, you are basically restating the problem, not solving it.
And how can you do this without recourse to some fluid dynamics?
Slightly more problematic is the smaller puffs further below the collapse front. I've read claims of 30, 40 and 50 floors below. Since there are only a couple of these, we can be quite sure that the lower portion of the tower was not over-pressurized to one psi, since that ought to be enough to break the glass and that event occurred only rarely. However, the initial shock to the tower of the airplane impact could well have cracked or broken the quarter inch plate glass in a few places about the structure. These, then, provided egress for the dusty air.
I don't find this convincing, at all.
* Well, not really, as fat tissue is lower density than muscle tissue.
QUOTE (metamars+Aug 10 2007, 10:24 PM)
Also, blown "down" through 6 flights of stairs is difficult to take literally. Most stairs that I've ever been in wrap around every floor. If this guy started to take a fall, he would soon have crashed against a wall, where the stairs makes a right angle turn. The implication is that the "wind" was so violent that he not only fell, but after smashing him against the wall, carried him off to the side and down again.
What sort of wind velocity does that imply? I'd guess at least a hurricane-strength wind (>74 mph). Considering the obesity epidemic in America, that guess may be way too low.* It also raises questions about how he survived, with enough intact bones to escape the building.
But an explosion also can't blow him round and round.
So PROBABLY the best idea is to ASK him to clarify what happened.
That's the problem with most of these type quotes, there is no cross examination to find out what actually happened vs what was a figure of speach.
Arthur
What sort of wind velocity does that imply? I'd guess at least a hurricane-strength wind (>74 mph). Considering the obesity epidemic in America, that guess may be way too low.* It also raises questions about how he survived, with enough intact bones to escape the building.
But an explosion also can't blow him round and round.
So PROBABLY the best idea is to ASK him to clarify what happened.
That's the problem with most of these type quotes, there is no cross examination to find out what actually happened vs what was a figure of speach.
Arthur
QUOTE (adoucette+Aug 10 2007, 01:44 PM)
If you want to see the impact angle of the plane see NIST NCSTAR 1-2B Fig E-24
The plane was on a downward angle ~ 10 deg below horizontal, and distributed fuel over 8 floors, including floors ABOVE where it hit.
I still wonder what newton thinks happens when fluid racing over a horizontal surface hits an open vertical shaft.
Arthur
i think it 'turns' 90 degrees. you know, ...the thing that lozenge said that the fuel did that wcfields tried to refute as stupid CTer nonsense.
the fuel was in the plane, and when the plane splattered like a water balloon, the fuel continued it's forward momentum until it hit something, and then deflected at the equal angle, for elevator shafts, that's basically ~90°.
i'm sure fuel would splash up as well as down. 90° up.
p.s.
QUOTE
But the CT'ers have NOT shown that these "squibs" need to be explained.
What IS clear is they don't occur until well after the building IS collapsing.
What IS clear is they don't occur until well after the building IS collapsing.
what is clear, is that you are not good at explaining what you see in videos.
"well after" is meaningless. that's okay, though. pedal what you will. keep digging that grave.
QUOTE (metamars+Aug 11 2007, 02:24 AM)
And I would expect that the area of the collapse front, over the voids in the core, but within the footprint of the buildings, is also 7%. Your point is? This suggests a pressure differential between core voids and core non-voids. Also, I suppose, you're suggesting a pressure differential between the core voids and non-core. However, as we have heard, again and again, that the WTC towers were mostly "empty space", what are you claiming that this pressure differential amounts to?
And somebody else (like myself) could take it as evidence of explosions, especially if (as I would expect) a serious analysis shows that any plausible gravity driven scenario would not have created any sort of wind such as you seem to imply.
Furthermore, due to the rapid rate that air pressure will equilibrate, why would not an advancing front result in a steadily increasing air pressure, rather than some sort of mysterious, squib-producing down draft?
Also, blown "down" through 6 flights of stairs is difficult to take literally. Most stairs that I've ever been in wrap around every floor. If this guy started to take a fall, he would soon have crashed against a wall, where the stairs makes a right angle turn. The implication is that the "wind" was so violent that he not only fell, but after smashing him against the wall, carried him off to the side and down again.
What sort of wind velocity does that imply? I'd guess at least a hurricane-strength wind (>74 mph). Considering the obesity epidemic in America, that guess may be way too low.* It also raises questions about how he survived, with enough intact bones to escape the building.
Actually, though, I'm glad you wrote this since:
If the "glass was long gone", that may suggest a reason for some of the explosions. Blown glass in lower floors might allow a 'draft' through the building, as it collapses, which might make for a tidier CD (as such a 'safety valve' would mean less over-pressure throughout the building, which means fewer windows breaking before the collapse front reaches them.) Such 'tidiness' would not be desirable ito after the collapse/CD was completed, but rather while it was occurring. Too much air pressure, and there might have rings of outwardly exploding windows preceding the collapse front, all the way down (but not with debris). One doesn't want to make CD obvious, unless, of course, as in the case of WTC 7, one has the power and intention to keep it off of the evening news.
You are using observations, which themselves are problematic ito a gravity driven scenario, to "explain" yet another observation which is problematic ito of gravity driven collapse. Since the basic task to to decide between competing hypotheses, using physics (where possible), I fail to see where you have advanced your argument.
If you want to do so, you should, e.g., demonstrate why a gravity driven collapse can blow a man not only down, but around 6 flights of stairs. Otherwise, you are basically restating the problem, not solving it.
And how can you do this without recourse to some fluid dynamics?
I don't find this convincing, at all.
* Well, not really, as fat tissue is lower density than muscle tissue.
QUOTE
And somebody else (like myself) could take it as evidence of explosions, especially if (as I would expect) a serious analysis shows that any plausible gravity driven scenario would not have created any sort of wind such as you seem to imply.
Has any Serious Analysis proved that air does not exist, given the variables to fluid dynamic flow, that is what you would have to do.
Please tell me when you do that I am lazy and could save a lot of energy by not breathing anymore.
I will not even comment on the rest of your post as most of it is irrelevant, any collapsing building will cause air movements, I have seen such from buildings of less than three stories that I have shoved in with a Bull Dozer.
We build buildings for the usable space inside, in other words for the spaces that contain air!
Ever tried to work or live inside a solid concrete cube?
QUOTE (newton+Aug 11 2007, 02:32 AM)
i think it 'turns' 90 degrees. you know, ...the thing that lozenge said that the fuel did that wcfields tried to refute as stupid CTer nonsense.
Actually what lozenge said was:
What I, and others have tried to point out is that GRAVITY will insure that fuel makes that INITIAL turn and there are THREE elevator shafts (and an unknown number of ventilation ducts) running from the impact zone to the basement.
So that shows that the "TOO MANY" qualifier is wrong.
NIST showed that the fuel made it to the shafts in 0.3 second, so that shows the "too much fuel burned up" is wrong
Then there are then MANY OTHER shafts that require but one more turn, something that gravity is pretty good on assisting with.
Which makes the entire quote, and your defense of it, more as you put it
What I, and others have tried to point out is that GRAVITY will insure that fuel makes that INITIAL turn and there are THREE elevator shafts (and an unknown number of ventilation ducts) running from the impact zone to the basement.
So that shows that the "TOO MANY" qualifier is wrong.
NIST showed that the fuel made it to the shafts in 0.3 second, so that shows the "too much fuel burned up" is wrong
Then there are then MANY OTHER shafts that require but one more turn, something that gravity is pretty good on assisting with.
Which makes the entire quote, and your defense of it, more as you put itstupid CTer nonsense
Arthur
Right, the Thermate Ninja Fairies were motivated to plant more explosives than was necessary to drop the building to make it look like explosives weren't used.
BS-meter polarity reversal, Grumpy was right.
Actually what lozenge said was:
QUOTE
I don't buy it: too many 90 degree turns, too much fuel being burned up in the fires at the top.
What I, and others have tried to point out is that GRAVITY will insure that fuel makes that INITIAL turn and there are THREE elevator shafts (and an unknown number of ventilation ducts) running from the impact zone to the basement.
So that shows that the "TOO MANY" qualifier is wrong.
NIST showed that the fuel made it to the shafts in 0.3 second, so that shows the "too much fuel burned up" is wrong
Then there are then MANY OTHER shafts that require but one more turn, something that gravity is pretty good on assisting with.
Which makes the entire quote, and your defense of it, more as you put it
QUOTE (->
| QUOTE |
| I don't buy it: too many 90 degree turns, too much fuel being burned up in the fires at the top. |
What I, and others have tried to point out is that GRAVITY will insure that fuel makes that INITIAL turn and there are THREE elevator shafts (and an unknown number of ventilation ducts) running from the impact zone to the basement.
So that shows that the "TOO MANY" qualifier is wrong.
NIST showed that the fuel made it to the shafts in 0.3 second, so that shows the "too much fuel burned up" is wrong
Then there are then MANY OTHER shafts that require but one more turn, something that gravity is pretty good on assisting with.
Which makes the entire quote, and your defense of it, more as you put itstupid CTer nonsense
Arthur
metamars
You keep bringing up "explosions" as if there was viable evidence of explosives being used. With the numerous instances(squibs, explosions in the stairwells, etc) there must be some sort of evidence that these explosives existed(not ambiguous claims of "it was like", "looked like" or "sounded like").
Since this is a science oreinted site we expect that claims of something's existence be supported by evidence, valid, testable, physical evidence. If you have valid physical evidence, present it.
Grumpy
You keep bringing up "explosions" as if there was viable evidence of explosives being used. With the numerous instances(squibs, explosions in the stairwells, etc) there must be some sort of evidence that these explosives existed(not ambiguous claims of "it was like", "looked like" or "sounded like").
Since this is a science oreinted site we expect that claims of something's existence be supported by evidence, valid, testable, physical evidence. If you have valid physical evidence, present it.
Grumpy
QUOTE (metamars+Aug 10 2007, 10:24 PM)
If the "glass was long gone", that may suggest a reason for some of the explosions. Blown glass in lower floors might allow a 'draft' through the building, as it collapses, which might make for a tidier CD (as such a 'safety valve' would mean less over-pressure throughout the building, which means fewer windows breaking before the collapse front reaches them.) Such 'tidiness' would not be desirable ito after the collapse/CD was completed, but rather while it was occurring. Too much air pressure, and there might have rings of outwardly exploding windows preceding the collapse front, all the way down (but not with debris). One doesn't want to make CD obvious, unless, of course, as in the case of WTC 7, one has the power and intention to keep it off of the evening news.
Friggin amazing.
Arthur
Friggin amazing.
Arthur
QUOTE
which might make for a tidier CD
Right, the Thermate Ninja Fairies were motivated to plant more explosives than was necessary to drop the building to make it look like explosives weren't used.
BS-meter polarity reversal, Grumpy was right.
QUOTE (adoucette+Aug 11 2007, 02:08 PM)
Actually what lozenge said was:
What I, and others have tried to point out is that GRAVITY will insure that fuel makes that INITIAL turn and there are THREE elevator shafts (and an unknown number of ventilation ducts) running from the impact zone to the basement.
So that shows that the "TOO MANY" qualifier is wrong.
NIST showed that the fuel made it to the shafts in 0.3 second, so that shows the "too much fuel burned up" is wrong
Then there are then MANY OTHER shafts that require but one more turn, something that gravity is pretty good on assisting with.
Which makes the entire quote, and your defense of it, more as you put it
What I, and others have tried to point out is that GRAVITY will insure that fuel makes that INITIAL turn and there are THREE elevator shafts (and an unknown number of ventilation ducts) running from the impact zone to the basement.
So that shows that the "TOO MANY" qualifier is wrong.
NIST showed that the fuel made it to the shafts in 0.3 second, so that shows the "too much fuel burned up" is wrong
Then there are then MANY OTHER shafts that require but one more turn, something that gravity is pretty good on assisting with.
Which makes the entire quote, and your defense of it, more as you put it
QUOTE (newton+)
stupid CTer nonsense
Arthur
Actually, I was referring to your contention that jet fuel could easily make it through the network of elevator shafts that DO NOT go directly to the lower levels.
Remember also that there is testimony from 911 survivors that many of the stairwells were blocked and impassable. The damage caused by the plane (in large part due to the momentum/mass of the fuel itself according to the Purdue study) would more likely obstruct the shafts rather than shear them off nicely for fuel to drop through. During the impact the fuel was also atomized "into a spray of fuel droplets" (NCSTAR1) and it stretches credulity to see how after the fuel impacts broke core columns/floors then atomized and partially ignited, it could come back together in the limited area of the access holes (that are not blockaded by debris) that lead downwards. Even if some of the jet fuel started downwards it would be spread on the walls/partially evaporate and tend to ignite from the upper fires - to have it then regroup in sufficient quantities 80 floors below to cause elevators (elevators - plural) to explode is a stretch to say the least. Especially considering this NIST quote: "Fortunately, there were not enough combustibles near elevators for major fires to start on the lower floors".
In the John Schroeder interview he notes how uninterested NIST was in his testimony when he was interviewed. From all the eyewitnesses, NIST could have probably pieced together a timeline with exactly which elevators exploded when, from where the supposed flash fires that blew out the lobby windows came from etc... Instead they just have a blanket statement of burning fuel shooting up and down the elevator shafts "blowing out doors and walls on other floors all the way down to the basement. Flash fires in the lobby blew out many of the plate glass windows." with no attempt to quantify anything (including how much fuel you would need to blow out multiple elevators as witnessed by Schroeder, let alone how this could happen 5 minutes after the supposed fireballs had traveled through the elevator shafts).
In any case, these issues are not self-evident so can we please keep the immature jeers and insults down to a minimum? It's interesting how conspicuously silent those same indignant posters are when unsubstantiated theories about "floors bageling ahead of the upper block" and "perimeter columns simply peeling outwards" are tossed around in this forum as if they are proven fact.
It would be the first time THIS government did such a thing.
Can you provide any other "evidence" to support this wild accusation?
And as for Lozenge's continuing assertion that the elevator shafts didn't line up vertically, one atop the other, that clearly shows that Lozenge STILL doesn't understand that his SCHEMATICS of the elevators weren't actual LAYOUTS of the elevators shafts, after FOUR ATTEMPTS on my part trying to explain the difference between a SCHEMATIC, which ONLY ILLUSTRATES A CONCEPT and a BLUEPRINT/ENGINEERING DRAWING that would be accurate, but confusing to those who have trouble understanding what they're looking at.
THOSE ELEVATOR SHAFTS LINED UP ONE ATOP THE OTHER!!!
Buy a clue!
Arthur[/QUOTE]
Actually, I was referring to your contention that jet fuel could easily make it through the network of elevator shafts that DO NOT go directly to the lower levels.
Oh really, where did I talk about a "network of elevator shafts"????
There are TOO MANY shafts that do go to the lobby, to worry about the ones who don't.
SEE POST: http://forum.physorg.com/index.php?showtop...ndpost&p=246429
Pay ATTENTION to the NIST LINKS.
Particularly the layout of the floors.
Pay attention to WHERE those elevator shafts end.
Pay attention to the ducting.
Pay attention.
Arthur
No, it isn't. WTC 7 fell because of the damage done when pieces of tower 1 ripped open the south wall and set it on fire. After burning for 7 1/2 hours(steel buildings are only rated to resist fire for 2 hours). There is no mistery to why it collapsed and there is no valid, PHYSICAL evidence of the use of explosives anywhere in the WTC complex.
By the way, still seeing firetrucks in the back window of BMWs???
lozenge124
No, it isn't. WTC 7 fell because of the damage done when pieces of tower 1 ripped open the south wall and set it on fire. After burning for 7 1/2 hours(steel buildings are only rated to resist fire for 2 hours). There is no mistery to why it collapsed and there is no valid, PHYSICAL evidence of the use of explosives anywhere in the WTC complex.
By the way, still seeing firetrucks in the back window of BMWs???
lozenge124
Remember also that there is testimony from 911 survivors that many of the stairwells were blocked and impassable.
Blocked or immpassible to a human being DOES NOT MEAN SEALED TO SUCH AN EXTENT THAT LIQUID FUEL COULD NOT POUR OR DRIP DOWNWARD THROUGH THEM. Geeze, I never thought you were THAT stupid.
50 TONS of fuel and you think NONE of it would spray, flow, pour or drip down through the disrupted(and far from sealed against liquids)elevator shafts???THAT IS JUST NONSENSE.
Liquids WILL reach the lowest level even if it has to perculate through several floors worth of rubble. It will pass through the 1/2 inch cracks between the floor and the elevator shafts, under elevator doors designed only to limit airflow(not to be water proof) and through expansion joints between concrete slabs. Fireballs going up and down elevator shafts were reported by many survivors on many floors.
That quote meant that it was a good thing there were few combustables outside of the elevators that the fireballs could set afire WHEN they blew out the elevators and doors or large fires would have been started on numerous floors in the lower section.
That quote meant that it was a good thing there were few combustables outside of the elevators that the fireballs could set afire WHEN they blew out the elevators and doors or large fires would have been started on numerous floors in the lower section.
Instead they just have a blanket statement of burning fuel shooting up and down the elevator shafts "blowing out doors and walls on other floors all the way down to the basement.
That statement just about says all that needs to be said. Fuel in the elevator shafts was responsible for NUMEROUS elevator/wall/door blowouts and, in the light of the whole event, chronicalling all of them is relatively unimportant. NIST knows where the damaging explosions originated from(elevator shafts), knows what caused them(fuel from the plane) and had reams of Eyewitness testimony to that effect(elevators blown out, doors blown out, fireballs erupting from shafts, people burned, etc, etc, all the way down to the subbasements. I'm sure NIST didn't think anyone would be so stupid as to deny what was witnessed by so many people. Scientists sometimes forget just how stupid some people can be and so fail to spell out what they consider obvious or self evident.
Fuel got into the elevator shafts and caused blowouts and fireballs all the way to the basements, this would have continued until no more fuel was available(probably until collapse), this is documented fact.
Grumpy
WTC7 is an obvious "viable evidence of explosives being used".
The way this building came down literally begged to be investigated (and this happening in one of the greatest crimes in history). So why was an investigation into its demise not looked into by the government until well over an half decade later when it should have been one of the very first things looked into? The suspicion surrounding it is far greater than that surrounding the twin towers' downfall. Can someone offer a credible answer to this question?
And why was the Bush administration completely averse to an investigation being done in the first place? They literally had to be forced into doing one...and the best they came up with was a travesty and a joke, the 9/11 Commission, as evidenced by their report. Feeble "political" or "incompetence" rationalizing given to explain the government's antagonistic stonewalling in this regard simply does not cut it; these are only excuses. The doubt and questions remain, and lest we forget, the Bush administration, the NeoCons, and others in consort with them have benefited greatly from this event, while to this day there still has not been a serious crime investigation done.
These are only two questions amongst a plethora that cast forbidding suspicion that elements within the US government were behind 9/11, that it was a false flag operation (or in their own words, a "new Pearl Harbor").
Bear in mind, this would not be the first time in history the power of government did such an atrocity against its own people.
THE PLANS OF THE HEART BELONG TO MAN
BUT THE ANSWER OF THE TONGUE IS FROM THE LORD
I wonder, if you have already been proven stupid, then why do you still post? If I were you I'd find a nice hole in the ground and hide in it.
I'm sorry newton, but you make no sense.
Something just occurred to me that I haven't seen discussed before.
The core columns had been supporting the upper block immediately prior to the collapse. This was an immense load, which would've compressed the core columns, shortening them by an amount proportional to the load, like a weight being supported by a spring, right?
But that was an awful long spring.
How much compression would that upper block have caused in the core structure? Inches, perhaps?
When the load was dropped, wouldn't that have caused the core to rebound vertically by that same amount?
If one core column broke and the one next to it hadn't broken yet, wouldn't that create a differential moment on the section of floor between the two points where the floor is connected to the two columns?
I'm thinking that perhaps the rebound of the core once it'd dropped it's overburden may have overstressed the floor supports and shattered the concrete floor slab(s).
DBB/Arthur - What sort of displacement(s) would we be looking at?
wow. sounds like a controlled demolition.
Wow, no, it doesn't.
I'd explain it to you if I thought for one moment that you were actually interested in the truth.
For the rest of us, what this implies is that the whole of the base of the core at the point where the upper block load is no longer being borne by the core columns would be acting like a spring under compression that's suddenly had a substantial release of some of its load, so it'll shoot upwards.
The rate that it shoots upwards is inversely proportional to the fraction of the remaining load to the original load, so it increases with floor height. The highest acceleration would be at the floor immediately below the dropped load. Say that the original load at floor X was 31 floors and the load at floor X after the dropped load was 1 floor, I'd expect the acceleration at floor X to be (initially) 31g's, attempting to accelerate floor X to the new position 0.877m/3 higher (about 1 foot). The supports for floor X aren't anywhere near that strong, so they'd fail, reducing the load on the core by one floor's worth, and the process would repeat for the floor below with similar results.
This assumes an instantaneous drop of load, which is, I recognize, unrealistic for the general case, but I'd expect something approaching this condition on at least some of the core columns, which would contribute to the core-side collapse.
The shearing noted wouldn't have been from floor impacts from above shearing them downwards, but would've been from core columns suddenly shooting up a foot, much faster that they could've accelerated the floors. (In the actual case, I'd expect a combination of the two mechanisms, with slower-unloaded core columns getting their floor supports sheared downwards from bagelling and the fast-unloaded core column floor supports getting sheared upwards from the mechanism described above.)
Differentials would've shattered the concrete between the two failure modes.
And,
8) It wasn't one of the tallest buildings in the world, so its designer could afford to make it more robust than something 110 stories tall.
They weren't destroyed CD-style. They collapsed from fire AND structural damage from impacts.
Brace yourself for this one, newton:
Have you ever noticed how "God" is "dog" spelled backwards?
Kinda makes you think, huh?
Arthur
Actually, I was referring to your contention that jet fuel could easily make it through the network of elevator shafts that DO NOT go directly to the lower levels.
Remember also that there is testimony from 911 survivors that many of the stairwells were blocked and impassable. The damage caused by the plane (in large part due to the momentum/mass of the fuel itself according to the Purdue study) would more likely obstruct the shafts rather than shear them off nicely for fuel to drop through. During the impact the fuel was also atomized "into a spray of fuel droplets" (NCSTAR1) and it stretches credulity to see how after the fuel impacts broke core columns/floors then atomized and partially ignited, it could come back together in the limited area of the access holes (that are not blockaded by debris) that lead downwards. Even if some of the jet fuel started downwards it would be spread on the walls/partially evaporate and tend to ignite from the upper fires - to have it then regroup in sufficient quantities 80 floors below to cause elevators (elevators - plural) to explode is a stretch to say the least. Especially considering this NIST quote: "Fortunately, there were not enough combustibles near elevators for major fires to start on the lower floors".
In the John Schroeder interview he notes how uninterested NIST was in his testimony when he was interviewed. From all the eyewitnesses, NIST could have probably pieced together a timeline with exactly which elevators exploded when, from where the supposed flash fires that blew out the lobby windows came from etc... Instead they just have a blanket statement of burning fuel shooting up and down the elevator shafts "blowing out doors and walls on other floors all the way down to the basement. Flash fires in the lobby blew out many of the plate glass windows." with no attempt to quantify anything (including how much fuel you would need to blow out multiple elevators as witnessed by Schroeder, let alone how this could happen 5 minutes after the supposed fireballs had traveled through the elevator shafts).
In any case, these issues are not self-evident so can we please keep the immature jeers and insults down to a minimum? It's interesting how conspicuously silent those same indignant posters are when unsubstantiated theories about "floors bageling ahead of the upper block" and "perimeter columns simply peeling outwards" are tossed around in this forum as if they are proven fact.
QUOTE (Grumpy+Aug 11 2007, 07:54 AM)
metamars
You keep bringing up "explosions" as if there was viable evidence of explosives being used.
Grumpy
WTC7 is an obvious "viable evidence of explosives being used".
The way this building came down literally begged to be investigated (and this happening in one of the greatest crimes in history). So why was an investigation into its demise not looked into by the government until well over an half decade later when it should have been one of the very first things looked into? The suspicion surrounding it is far greater than that surrounding the twin towers' downfall. Can someone offer a credible answer to this question?
And why was the Bush administration completely averse to an investigation being done in the first place? They literally had to be forced into doing one...and the best they came up with was a travesty and a joke, the 9/11 Commission, as evidenced by their report. Feeble "political" or "incompetence" rationalizing given to explain the government's antagonistic stonewalling in this regard simply does not cut it; these are only excuses. The doubt and questions remain, and lest we forget, the Bush administration, the NeoCons, and others in consort with them have benefited greatly from this event, while to this day there still has not been a serious crime investigation done.
These are only two questions amongst a plethora that cast forbidding suspicion that elements within the US government were behind 9/11, that it was a false flag operation (or in their own words, a "new Pearl Harbor").
Bear in mind, this would not be the first time in history the power of government did such an atrocity against its own people.
THE PLANS OF THE HEART BELONG TO MAN
BUT THE ANSWER OF THE TONGUE IS FROM THE LORD
You keep bringing up "explosions" as if there was viable evidence of explosives being used.
Grumpy
WTC7 is an obvious "viable evidence of explosives being used".
The way this building came down literally begged to be investigated (and this happening in one of the greatest crimes in history). So why was an investigation into its demise not looked into by the government until well over an half decade later when it should have been one of the very first things looked into? The suspicion surrounding it is far greater than that surrounding the twin towers' downfall. Can someone offer a credible answer to this question?
And why was the Bush administration completely averse to an investigation being done in the first place? They literally had to be forced into doing one...and the best they came up with was a travesty and a joke, the 9/11 Commission, as evidenced by their report. Feeble "political" or "incompetence" rationalizing given to explain the government's antagonistic stonewalling in this regard simply does not cut it; these are only excuses. The doubt and questions remain, and lest we forget, the Bush administration, the NeoCons, and others in consort with them have benefited greatly from this event, while to this day there still has not been a serious crime investigation done.
These are only two questions amongst a plethora that cast forbidding suspicion that elements within the US government were behind 9/11, that it was a false flag operation (or in their own words, a "new Pearl Harbor").
Bear in mind, this would not be the first time in history the power of government did such an atrocity against its own people.
THE PLANS OF THE HEART BELONG TO MAN
BUT THE ANSWER OF THE TONGUE IS FROM THE LORD
QUOTE (metamars+Aug 10 2007, 07:24 PM)
And I would expect that the area of the collapse front, over the voids in the core, but within the footprint of the buildings, is also 7%. Your point is?
This suggests a pressure differential between core voids and core non-voids. Also, I suppose, you're suggesting a pressure differential between the core voids and non-core. However, as we have heard, again and again, that the WTC towers were mostly "empty space", what are you claiming that this pressure differential amounts to?
(1) Some of the 12 acre-feet of air escaped down the voids, more than 7% IMO.
(2) Enough to blow the man down and around 6 flights of stairs and blow several floors high worth of materials out the lobby and also produce the puffs of air under contention. This is perforce going to have to be qualitative, conceptual physics.
As for the rest of your post, I found it too bizarre to bother responding to. However, I will add that just as it is known that elevator doors were blown open at the lobby level and also on floor 23, so it is possible that similar effects occurred on the floors with the small puffs of air. Hence some of the over-pressure went onto those floors. If one psi over-pressure sufficed to break windows, then it only requires an additional 6.8% pressure above one atm to accomplish this. This seems to be the simplest explanation.
This suggests a pressure differential between core voids and core non-voids. Also, I suppose, you're suggesting a pressure differential between the core voids and non-core. However, as we have heard, again and again, that the WTC towers were mostly "empty space", what are you claiming that this pressure differential amounts to?
(1) Some of the 12 acre-feet of air escaped down the voids, more than 7% IMO.
(2) Enough to blow the man down and around 6 flights of stairs and blow several floors high worth of materials out the lobby and also produce the puffs of air under contention. This is perforce going to have to be qualitative, conceptual physics.
As for the rest of your post, I found it too bizarre to bother responding to. However, I will add that just as it is known that elevator doors were blown open at the lobby level and also on floor 23, so it is possible that similar effects occurred on the floors with the small puffs of air. Hence some of the over-pressure went onto those floors. If one psi over-pressure sufficed to break windows, then it only requires an additional 6.8% pressure above one atm to accomplish this. This seems to be the simplest explanation.
QUOTE
Bear in mind, this would not be the first time in history the power of government did such an atrocity against its own people.
It would be the first time THIS government did such a thing.
Can you provide any other "evidence" to support this wild accusation?
And as for Lozenge's continuing assertion that the elevator shafts didn't line up vertically, one atop the other, that clearly shows that Lozenge STILL doesn't understand that his SCHEMATICS of the elevators weren't actual LAYOUTS of the elevators shafts, after FOUR ATTEMPTS on my part trying to explain the difference between a SCHEMATIC, which ONLY ILLUSTRATES A CONCEPT and a BLUEPRINT/ENGINEERING DRAWING that would be accurate, but confusing to those who have trouble understanding what they're looking at.
THOSE ELEVATOR SHAFTS LINED UP ONE ATOP THE OTHER!!!
Buy a clue!
QUOTE (lozenge124+Aug 11 2007, 04:16 PM)
Arthur[/QUOTE]
Actually, I was referring to your contention that jet fuel could easily make it through the network of elevator shafts that DO NOT go directly to the lower levels.
Oh really, where did I talk about a "network of elevator shafts"????
There are TOO MANY shafts that do go to the lobby, to worry about the ones who don't.
SEE POST: http://forum.physorg.com/index.php?showtop...ndpost&p=246429
Pay ATTENTION to the NIST LINKS.
Particularly the layout of the floors.
Pay attention to WHERE those elevator shafts end.
Pay attention to the ducting.
Pay attention.
Arthur
QUOTE (quicknthedead+Aug 11 2007, 04:36 PM)
So why was an investigation into its demise not looked into by the government until well over an half decade later when it should have been one of the very first things looked into?
NOPE.
The building was just fine until another building that was hit by a hijacked jet, collapsed and in doing so created a large but also somewhat unknown amount of structural damage to WTC 7 and set it on fire, which, because of the UNIQUE situation that day, was allowed to burn unchecked for many hours past the time that a steel building is REQUIRED to stand, such that its collapse was both expected and, in fact, almost inevitable.
Only to CT'ers with thier own agenda.
Arthur
NOPE.
The building was just fine until another building that was hit by a hijacked jet, collapsed and in doing so created a large but also somewhat unknown amount of structural damage to WTC 7 and set it on fire, which, because of the UNIQUE situation that day, was allowed to burn unchecked for many hours past the time that a steel building is REQUIRED to stand, such that its collapse was both expected and, in fact, almost inevitable.
QUOTE
WTC7 is an obvious "viable evidence of explosives being used".
Only to CT'ers with thier own agenda.
Arthur
QUOTE
WTC7 is an obvious "viable evidence of explosives being used".
No, it isn't. WTC 7 fell because of the damage done when pieces of tower 1 ripped open the south wall and set it on fire. After burning for 7 1/2 hours(steel buildings are only rated to resist fire for 2 hours). There is no mistery to why it collapsed and there is no valid, PHYSICAL evidence of the use of explosives anywhere in the WTC complex.
By the way, still seeing firetrucks in the back window of BMWs???
lozenge124
QUOTE (->
| QUOTE |
| WTC7 is an obvious "viable evidence of explosives being used". |
No, it isn't. WTC 7 fell because of the damage done when pieces of tower 1 ripped open the south wall and set it on fire. After burning for 7 1/2 hours(steel buildings are only rated to resist fire for 2 hours). There is no mistery to why it collapsed and there is no valid, PHYSICAL evidence of the use of explosives anywhere in the WTC complex.
By the way, still seeing firetrucks in the back window of BMWs???
lozenge124
Remember also that there is testimony from 911 survivors that many of the stairwells were blocked and impassable.
Blocked or immpassible to a human being DOES NOT MEAN SEALED TO SUCH AN EXTENT THAT LIQUID FUEL COULD NOT POUR OR DRIP DOWNWARD THROUGH THEM. Geeze, I never thought you were THAT stupid.
50 TONS of fuel and you think NONE of it would spray, flow, pour or drip down through the disrupted(and far from sealed against liquids)elevator shafts???THAT IS JUST NONSENSE.
Liquids WILL reach the lowest level even if it has to perculate through several floors worth of rubble. It will pass through the 1/2 inch cracks between the floor and the elevator shafts, under elevator doors designed only to limit airflow(not to be water proof) and through expansion joints between concrete slabs. Fireballs going up and down elevator shafts were reported by many survivors on many floors.
QUOTE
Especially considering this NIST quote: "Fortunately, there were not enough combustibles near elevators for major fires to start on the lower floors".
That quote meant that it was a good thing there were few combustables outside of the elevators that the fireballs could set afire WHEN they blew out the elevators and doors or large fires would have been started on numerous floors in the lower section.
QUOTE (->
| QUOTE |
| Especially considering this NIST quote: "Fortunately, there were not enough combustibles near elevators for major fires to start on the lower floors". |
That quote meant that it was a good thing there were few combustables outside of the elevators that the fireballs could set afire WHEN they blew out the elevators and doors or large fires would have been started on numerous floors in the lower section.
Instead they just have a blanket statement of burning fuel shooting up and down the elevator shafts "blowing out doors and walls on other floors all the way down to the basement.
That statement just about says all that needs to be said. Fuel in the elevator shafts was responsible for NUMEROUS elevator/wall/door blowouts and, in the light of the whole event, chronicalling all of them is relatively unimportant. NIST knows where the damaging explosions originated from(elevator shafts), knows what caused them(fuel from the plane) and had reams of Eyewitness testimony to that effect(elevators blown out, doors blown out, fireballs erupting from shafts, people burned, etc, etc, all the way down to the subbasements. I'm sure NIST didn't think anyone would be so stupid as to deny what was witnessed by so many people. Scientists sometimes forget just how stupid some people can be and so fail to spell out what they consider obvious or self evident.
Fuel got into the elevator shafts and caused blowouts and fireballs all the way to the basements, this would have continued until no more fuel was available(probably until collapse), this is documented fact.
Grumpy
QUOTE (deadnthedead+Aug 11 2007, 03:36 PM)
WTC7 is an obvious "viable evidence of explosives being used".
The way this building came down literally begged to be investigated (and this happening in one of the greatest crimes in history). So why was an investigation into its demise not looked into by the government until well over an half decade later when it should have been one of the very first things looked into? The suspicion surrounding it is far greater than that surrounding the twin towers' downfall. Can someone offer a credible answer to this question?
And why was the Bush administration completely averse to an investigation being done in the first place? They literally had to be forced into doing one...and the best they came up with was a travesty and a joke, the 9/11 Commission, as evidenced by their report. Feeble "political" or "incompetence" rationalizing given to explain the government's antagonistic stonewalling in this regard simply does not cut it; these are only excuses. The doubt and questions remain, and lest we forget, the Bush administration, the NeoCons, and others in consort with them have benefited greatly from this event, while to this day there still has not been a serious crime investigation done.
These are only two questions amongst a plethora that cast forbidding suspicion that elements within the US government were behind 9/11, that it was a false flag operation (or in their own words, a "new Pearl Harbor").
Bear in mind, this would not be the first time in history the power of government did such an atrocity against its own people.
THE PLANS OF THE HEART BELONG TO MAN
BUT THE ANSWER OF THE TONGUE IS FROM THE LORD
I wonder, if you have already been proven stupid, then why do you still post? If I were you I'd find a nice hole in the ground and hide in it.
Properly starting the collapse calculation from floor 98 reduces E1 even further:
E1 = 348.3 megajoules
for the first 3 seconds of the drop of WTC 1.
E1 = 348.3 megajoules
for the first 3 seconds of the drop of WTC 1.
Dude, I can't believe this post is still going. I have proven them wrong, Grumpy has proven them wrong, adoucette has proven them wrong. I'm sure you have several times. It's like beating a dead horse until it starts to smell, then grabbing a shovel and whacking it with it.
Re 7
No damage my big ol' butt!!!
Grumpy
No damage my big ol' butt!!!
Grumpy
QUOTE (David B. Benson+Aug 9 2007, 11:08 PM)
Corrected estimate of E1 is only 72% of the previous estimate. The new estimate is
367 megajoules,
which is the smallest estimate I have (so far) seen. This is good, because it drives down the embarrassingly large amount of unexplained energy consumption.
That's great David, I've some questions, you found the acceleration
1) What is the value of the acceleration you found ?
2) Since the mass of the top block is unknown (recent estimates say that the whole building might be a factor lower) it would make more sense to use the ratio of it as a value and use that in the rest of the calculations.
3) How is the vlaue determined, is the F(y) function assumed to be constant, is it a peak force, i.e. a delta function or is a lineair function at the whole elastic phase used and then a plasti part and then a total break ?
4) Is the thickness of the floors included, I think it is not really relevant but is it ?
Since this is a weak and extremely damaged story my conclusion is that an intact story would be a factor stronger and E_intact_story > E1=E_14
5) In reality would the value not increase if you go to the bottom, that might be an explanation (Newtons Bit@jref came with that) why the energy is dissipated in steps. But I'm not convinced.
btw I hate the notation E1, NEU-FONZE why did you choose it, you are a professional..
367 megajoules,
which is the smallest estimate I have (so far) seen. This is good, because it drives down the embarrassingly large amount of unexplained energy consumption.
That's great David, I've some questions, you found the acceleration
1) What is the value of the acceleration you found ?
2) Since the mass of the top block is unknown (recent estimates say that the whole building might be a factor lower) it would make more sense to use the ratio of it as a value and use that in the rest of the calculations.
3) How is the vlaue determined, is the F(y) function assumed to be constant, is it a peak force, i.e. a delta function or is a lineair function at the whole elastic phase used and then a plasti part and then a total break ?
4) Is the thickness of the floors included, I think it is not really relevant but is it ?
Since this is a weak and extremely damaged story my conclusion is that an intact story would be a factor stronger and E_intact_story > E1=E_14
5) In reality would the value not increase if you go to the bottom, that might be an explanation (Newtons Bit@jref came with that) why the energy is dissipated in steps. But I'm not convinced.
btw I hate the notation E1, NEU-FONZE why did you choose it, you are a professional..
QUOTE (David B. Benson+Aug 9 2007, 10:49 PM)
(2) That is attempting to discuss collapse initiation, not the progressive collapse itself.
Indeed, I tried to understand initiation, I don't understand a single word of that theory, outward bowing in the elastic phase, trusses that sag in and finally deliver a shrinking force to pull them in. It doesn't make sense for me, but of course I'm a little bit lazy and need to read 10,000 papers.
Indeed, I tried to understand initiation, I don't understand a single word of that theory, outward bowing in the elastic phase, trusses that sag in and finally deliver a shrinking force to pull them in. It doesn't make sense for me, but of course I'm a little bit lazy and need to read 10,000 papers.
QUOTE (einsteen+Aug 13 2007, 03:15 PM)
Indeed, I tried to understand initiation, I don't understand a single word of that theory, outward bowing in the elastic phase, trusses that sag in and finally deliver a shrinking force to pull them in. It doesn't make sense for me, but of course I'm a little bit lazy and need to read 10,000 papers.
Initiation, is basically the bowing of the trusses increasing the tension on the interior core beams, adding to the buckling. The beams can only resist so much side tension before the welds fail.
Initiation, is basically the bowing of the trusses increasing the tension on the interior core beams, adding to the buckling. The beams can only resist so much side tension before the welds fail.
QUOTE (einsteen+Aug 13 2007, 08:11 AM)
1) What is the value of the acceleration you found ?
2) Since the mass of the top block is unknown (recent estimates say that the whole building might be a factor lower) it would make more sense to use the ratio of it as a value and use that in the rest of the calculations.
3) How is the vlaue[sic] determined, is the F(y) function assumed to be constant, is it a peak force, i.e. a delta function or is a lineair[sic] function at the whole elastic phase used and then a plasti[sic] part and then a total break ?
4) Is the thickness of the floors included, I think it is not really relevant but is it ?
5) In reality would the value not increase if you go to the bottom, that might be an explanation (Newtons Bit@jref came with that) why the energy is dissipated in steps. But I'm not convinced.
1) Same as before, about (2/3)g for WTC 1.
2) The mass is known. See NCSTAR1--6 or NCSTAR1--6D. Precisely, 33,178 tonnes for WTC 1.
3) The resistive force is taken to be constant for the period of measurement, 3 seconds. In this time 10 floors are crushed, and all are trussed floors. (WTC 1)
4) The B & V crush-down equation assumes a homogeneous structure, so the question is not relevant.
5) The resistive force does increase as the collapse progresses downwards. See the BLGB paper for details. (I only do the first 3 seconds.) However, it is abundantly clear that energy is expended continuously. The step model is merely a convenience.
2) Since the mass of the top block is unknown (recent estimates say that the whole building might be a factor lower) it would make more sense to use the ratio of it as a value and use that in the rest of the calculations.
3) How is the vlaue[sic] determined, is the F(y) function assumed to be constant, is it a peak force, i.e. a delta function or is a lineair[sic] function at the whole elastic phase used and then a plasti[sic] part and then a total break ?
4) Is the thickness of the floors included, I think it is not really relevant but is it ?
5) In reality would the value not increase if you go to the bottom, that might be an explanation (Newtons Bit@jref came with that) why the energy is dissipated in steps. But I'm not convinced.
1) Same as before, about (2/3)g for WTC 1.
2) The mass is known. See NCSTAR1--6 or NCSTAR1--6D. Precisely, 33,178 tonnes for WTC 1.
3) The resistive force is taken to be constant for the period of measurement, 3 seconds. In this time 10 floors are crushed, and all are trussed floors. (WTC 1)
4) The B & V crush-down equation assumes a homogeneous structure, so the question is not relevant.
5) The resistive force does increase as the collapse progresses downwards. See the BLGB paper for details. (I only do the first 3 seconds.) However, it is abundantly clear that energy is expended continuously. The step model is merely a convenience.
QUOTE (Chainsaw,+Aug 13 2007, 09:51 AM)
Initiation, is basically the bowing of the trusses increasing the tension on the interior core beams, adding to the buckling. The beams can only resist so much side tension before the welds fail.
Interesting speculation. NIST states that the pull-in force applied to the exterior wall pulled the walls in and then the walls buckled. This event is considered to be the collapse initiation time.
However, in WTC 1, about 2 seconds earlier there were expulsions of smoke and flame on floors 98 and 97. This, to me, appears to be due to a partial floor collapse. There is a distinct possibility that at this time the antenna tower began to lean sufficiently far to the south that we will be able to detect it in a video. Such a lean implies some additional compression of core columns, which then, via hat truss transfer, could increase the loads on the exterior walls, finally causing the walls to buckle.
All just additional speculation at this time...
Interesting speculation. NIST states that the pull-in force applied to the exterior wall pulled the walls in and then the walls buckled. This event is considered to be the collapse initiation time.
However, in WTC 1, about 2 seconds earlier there were expulsions of smoke and flame on floors 98 and 97. This, to me, appears to be due to a partial floor collapse. There is a distinct possibility that at this time the antenna tower began to lean sufficiently far to the south that we will be able to detect it in a video. Such a lean implies some additional compression of core columns, which then, via hat truss transfer, could increase the loads on the exterior walls, finally causing the walls to buckle.
All just additional speculation at this time...
QUOTE (einsteen+Aug 13 2007, 08:11 AM)
Since this is a weak and extremely damaged story my conclusion is that an intact story would be a factor stronger and E_intact_story > E1=E_14
Not how E1 is determined. First of all, assume it is constant for the 3 seconds of data. Then obtain the best fit between the crush-down equation and the data measured by NEU-FONZE. The only parameter to adjust is, in effect, E1.
The collapse of WTC 1 is taken to start at floor 98, according to NIST. I certainly agree that floors 98 and 97 were weak and extremely damaged. That is why to collapse begins there, IMO. But the determination of E1 is an average over the next 10 floors down, most of which were intact.
Not how E1 is determined. First of all, assume it is constant for the 3 seconds of data. Then obtain the best fit between the crush-down equation and the data measured by NEU-FONZE. The only parameter to adjust is, in effect, E1.
The collapse of WTC 1 is taken to start at floor 98, according to NIST. I certainly agree that floors 98 and 97 were weak and extremely damaged. That is why to collapse begins there, IMO. But the determination of E1 is an average over the next 10 floors down, most of which were intact.
Absolutely David. The first stories where very weak and when the velocity increases the collapsing mass also does. After a couple of stories that collaping mass increases dramatically and the ratio with the E values will be relevant.
I this the formula you use ?
E=h_story*Mass_block*(g-a_wtc1)
The mass you mentioned implies that the building is 2.6*10^8 kg instead of 5.1*10^8 kg, but if I use your values the above gives 400 MJ
- There are some points to add, the measure of the antenna is a nice approach but also the drop of the hat-truss should be done later, at the left and right side for example because since that antenna topples exactly to the opposite side as the video it already moves before the movement of the hat truss can be seen.
- If the acceleration is not constant in time, i.e. a=a(t) then the fitting at t=0 is a problem, on the one hand you need more points for a reliable value but if you have more points you include those far away from the initial acceleration. Is it an idea to use the x(t) function from the model itself and try to fit that one the drop diagram of the building? In that case it is even possible to say something about the implicit function E(x), although that will be far from trivial...
I this the formula you use ?
E=h_story*Mass_block*(g-a_wtc1)
The mass you mentioned implies that the building is 2.6*10^8 kg instead of 5.1*10^8 kg, but if I use your values the above gives 400 MJ
- There are some points to add, the measure of the antenna is a nice approach but also the drop of the hat-truss should be done later, at the left and right side for example because since that antenna topples exactly to the opposite side as the video it already moves before the movement of the hat truss can be seen.
- If the acceleration is not constant in time, i.e. a=a(t) then the fitting at t=0 is a problem, on the one hand you need more points for a reliable value but if you have more points you include those far away from the initial acceleration. Is it an idea to use the x(t) function from the model itself and try to fit that one the drop diagram of the building? In that case it is even possible to say something about the implicit function E(x), although that will be far from trivial...
QUOTE (David B. Benson+Aug 13 2007, 09:24 PM)
Interesting speculation. NIST states that the pull-in force applied to the exterior wall pulled the walls in and then the walls buckled. This event is considered to be the collapse initiation time.
However, in WTC 1, about 2 seconds earlier there were expulsions of smoke and flame on floors 98 and 97. This, to me, appears to be due to a partial floor collapse. There is a distinct possibility that at this time the antenna tower began to lean sufficiently far to the south that we will be able to detect it in a video. Such a lean implies some additional compression of core columns, which then, via hat truss transfer, could increase the loads on the exterior walls, finally causing the walls to buckle.
All just additional speculation at this time...
If I have anymore Ideas I will pass them along, just noticing that floors dropping would help to put pressure on the perimeter columns and Core Columns, and the most likely failure point is the floor cross beams, that also allows the side of the core columns to give way, and that is the weakest point, so that asymmetrical collapse is transfered to symmetrical collapse with the least tans fer of energy.
In other words disconnect the points that give the beams the ability to resist side loading and the beams fail from the weight sooner. with less of a fulcrum the beams remain UN bowed because the Buckling needed to snap the welds is not as great as in the side that has the most weld contact area.
However, in WTC 1, about 2 seconds earlier there were expulsions of smoke and flame on floors 98 and 97. This, to me, appears to be due to a partial floor collapse. There is a distinct possibility that at this time the antenna tower began to lean sufficiently far to the south that we will be able to detect it in a video. Such a lean implies some additional compression of core columns, which then, via hat truss transfer, could increase the loads on the exterior walls, finally causing the walls to buckle.
All just additional speculation at this time...
If I have anymore Ideas I will pass them along, just noticing that floors dropping would help to put pressure on the perimeter columns and Core Columns, and the most likely failure point is the floor cross beams, that also allows the side of the core columns to give way, and that is the weakest point, so that asymmetrical collapse is transfered to symmetrical collapse with the least tans fer of energy.
In other words disconnect the points that give the beams the ability to resist side loading and the beams fail from the weight sooner. with less of a fulcrum the beams remain UN bowed because the Buckling needed to snap the welds is not as great as in the side that has the most weld contact area.
I think the falling of the floors could be compared to a technique of braking stacked bricks by use of a karate chop.
The outer edge of the floors would hold, but the center begins to compound the forces as they fall from one floor to the next.
As I suggested before it may act like an implosion as each floor pulls the outer walls inward while each floor fails to hold.
The outer edge of the floors would hold, but the center begins to compound the forces as they fall from one floor to the next.
As I suggested before it may act like an implosion as each floor pulls the outer walls inward while each floor fails to hold.
Einsteen:
You say: "btw I hate the notation E1, NEU-FONZE why did you choose it, you are a professional.. "
What's wrong with it?!?
It represents the effective energy to collapse ONE floor. It's a theoretical concept. It involves an amount of ENERGY, so I used "E"...
Einsteen, what notation would you prefer?
You say: "btw I hate the notation E1, NEU-FONZE why did you choose it, you are a professional.. "
What's wrong with it?!?
It represents the effective energy to collapse ONE floor. It's a theoretical concept. It involves an amount of ENERGY, so I used "E"...
Einsteen, what notation would you prefer?
I'm sorry, I downloaded the article very long time ago and was convinced that it contained E1 instead of the notation with the lower index E_1 (in TeX), maybe I was confused because that cannot be written here, apologize, I wanted to make a kind of nitpicker joke, but it was already good in the article of course.. just googled it back... Of course it is the best notation..hell I have to prepare those kinds of jokes better
Cheers,
Ed (having a tomato red face now)
Cheers,
Ed (having a tomato red face now)
QUOTE (einsteen+Aug 14 2007, 01:43 AM)
I[sic] this the formula you use ?
- If the acceleration is not constant in time, ...
No. The formula is the crush-down differential equation from the paper by Bazant & Verdure, which you can find on Professor Bazant's web site.
The acceleration is not constant, beginning high and surging negatively as time progresses.
- If the acceleration is not constant in time, ...
No. The formula is the crush-down differential equation from the paper by Bazant & Verdure, which you can find on Professor Bazant's web site.
The acceleration is not constant, beginning high and surging negatively as time progresses.
QUOTE (rethinker+Aug 14 2007, 05:43 AM)
The outer edge of the floors would hold, but the center begins to compound the forces as they fall from one floor to the next.
As I suggested before it may act like an implosion as each floor pulls the outer walls inward while each floor fails to hold.
The outer edge of the trusses sat on truss seats. There is visual evidence that these failed. Due to the tilt, it is clear that the upper exterior walls simply sliced the trusses from the seats. For example, the floor which took the longest time to be crushed was floor 97 of WTC 1. Even so, the south half of the floor was crushed in only 0.4 seconds.
From the videos, the exterior walls went outwards, not inwards.
As I suggested before it may act like an implosion as each floor pulls the outer walls inward while each floor fails to hold.
The outer edge of the trusses sat on truss seats. There is visual evidence that these failed. Due to the tilt, it is clear that the upper exterior walls simply sliced the trusses from the seats. For example, the floor which took the longest time to be crushed was floor 97 of WTC 1. Even so, the south half of the floor was crushed in only 0.4 seconds.
From the videos, the exterior walls went outwards, not inwards.
I got the result from NF's stepwise model.
You say that the acceleration decreases ? I've worked out the discrete model in detail, what am I doing wrong ? I get the exact Greening end velocity at a fall of 96 floors, i.e. about 51 m/s, if I compare it with 2g/3 then I would say that the collapse model's acceleration increases, which is also consistent with constant E1 and increasing collapsing mass, the ratio goes to zero.
maple plot http://i17.tinypic.com/6czec03.gif
Derivation will follow later (is a very general formula where I added w=1, i.e. no mass ejected)
ps. Hell I used the identity a=v^2/2l to plot the distance (in k units) - velocity function,
It's too late and I had a long day solving software conflicts, I think I have to take it easy....later
psII. of course it decreases because if you plot a couple of velocities as function of the floor for g, 2g/3 etc it is the slope that matters at that point and not the velocity. Or ?? Now really bed...
You say that the acceleration decreases ? I've worked out the discrete model in detail, what am I doing wrong ? I get the exact Greening end velocity at a fall of 96 floors, i.e. about 51 m/s, if I compare it with 2g/3 then I would say that the collapse model's acceleration increases, which is also consistent with constant E1 and increasing collapsing mass, the ratio goes to zero.
maple plot http://i17.tinypic.com/6czec03.gif
Derivation will follow later (is a very general formula where I added w=1, i.e. no mass ejected)
ps. Hell I used the identity a=v^2/2l to plot the distance (in k units) - velocity function,
It's too late and I had a long day solving software conflicts, I think I have to take it easy....laterpsII. of course it decreases because if you plot a couple of velocities as function of the floor for g, 2g/3 etc it is the slope that matters at that point and not the velocity. Or ?? Now really bed...
QUOTE (einsteen+Aug 14 2007, 01:43 AM)
E=h_story*Mass_block*(g-a_wtc1)
The mass you mentioned implies that the building is 2.6*10^8 kg instead of 5.1*10^8 kg, but if I use your values the above gives 400 MJ
This formula is a surprisingly good approximation, once one properly accounts for the stretch, s, by multiplying by (1-s). I use s = 0.14, which gives, then, (0.86)400 = 344 MJ. Almost the calculated 348 MJ!
shagster, using NIST's database and SAP2000 program worked out that each tower massed, with contents, close to 300,000 tonnes. The mass per story in general increases downwards...
The mass you mentioned implies that the building is 2.6*10^8 kg instead of 5.1*10^8 kg, but if I use your values the above gives 400 MJ
This formula is a surprisingly good approximation, once one properly accounts for the stretch, s, by multiplying by (1-s). I use s = 0.14, which gives, then, (0.86)400 = 344 MJ. Almost the calculated 348 MJ!
shagster, using NIST's database and SAP2000 program worked out that each tower massed, with contents, close to 300,000 tonnes. The mass per story in general increases downwards...
yeah. the mass increases downwards. try and crush a pyramid with the *missing* cap.
I'm sorry newton, but you make no sense.
sorry. missing capstone.
now it makes sense.
now it makes sense.
QUOTE (newton+Aug 15 2007, 12:03 PM)
sorry. missing capstone.
now it makes sense.
NOPE.
The MAJORITY of the steel structure was not CRUSHED.
The concrete and contents were crushed, but they DID NOT increase in strength as you go down. The fact that acre size sheets of 4" lightweight concrete did in fact crumble is not at all surprising (well except to CTers)
The Perimeter columns were, for the most part, splayed outward and were neither crushed nor seriously bent. The most common damage seen in multitudes of the perimeter trees was simply bolt failure and truss seat failure.
The Core columns were broken by the kinetic forces of the collapse, but again, not CRUSHED.
Again not surprising considering the amount of energy available.
Arthur
now it makes sense.
NOPE.
The MAJORITY of the steel structure was not CRUSHED.
The concrete and contents were crushed, but they DID NOT increase in strength as you go down. The fact that acre size sheets of 4" lightweight concrete did in fact crumble is not at all surprising (well except to CTers)
The Perimeter columns were, for the most part, splayed outward and were neither crushed nor seriously bent. The most common damage seen in multitudes of the perimeter trees was simply bolt failure and truss seat failure.
The Core columns were broken by the kinetic forces of the collapse, but again, not CRUSHED.
Again not surprising considering the amount of energy available.
Arthur
QUOTE (adoucette+Aug 15 2007, 04:21 PM)
The Perimeter columns were, for the most part, splayed outward and were neither crushed nor seriously bent. The most common damage seen in multitudes of the perimeter trees was simply bolt failure and truss seat failure.
The Core columns were broken by the kinetic forces of the collapse, but again, not CRUSHED.
Again not surprising considering the amount of energy available.
It is not just a question of how much energy is available, it is also a question of how it is distributed and directed.
If you consider that the perimeter and core columns were vertical, and that the kinetic energy of the upper block was also vertical - in the same vector direction as gravity - it becomes problematic to explain how the columns could fail at the bolt connections without displaying any bending. Can you push downwards on two vertically bolted columns and break the joint between the two without any column bending?
Another surprising feature under these considerations is the "floor by floor" progressive nature of the collapse - if the crushing force is vertical, how can it knock out the column bolt connections on one horizontal level (one floor) without causing any damage further down?
To break off the perimeter column sections as described ("bolt failure and truss seat failure", plus progressive collapse) you need a large horizontal force component. There may have been enough energy available as the upper block's potential energy was converted into kinetic energy, but it was mostly directed vertically, and no mechanism has yet been proposed for how this energy could manifest itself in horizontal component forces directed outwards...
Energetic consideration are necessary conditions, but not sufficient.
The Core columns were broken by the kinetic forces of the collapse, but again, not CRUSHED.
Again not surprising considering the amount of energy available.
It is not just a question of how much energy is available, it is also a question of how it is distributed and directed.
If you consider that the perimeter and core columns were vertical, and that the kinetic energy of the upper block was also vertical - in the same vector direction as gravity - it becomes problematic to explain how the columns could fail at the bolt connections without displaying any bending. Can you push downwards on two vertically bolted columns and break the joint between the two without any column bending?
Another surprising feature under these considerations is the "floor by floor" progressive nature of the collapse - if the crushing force is vertical, how can it knock out the column bolt connections on one horizontal level (one floor) without causing any damage further down?
To break off the perimeter column sections as described ("bolt failure and truss seat failure", plus progressive collapse) you need a large horizontal force component. There may have been enough energy available as the upper block's potential energy was converted into kinetic energy, but it was mostly directed vertically, and no mechanism has yet been proposed for how this energy could manifest itself in horizontal component forces directed outwards...
Energetic consideration are necessary conditions, but not sufficient.
QUOTE (lozenge124+Aug 15 2007, 01:40 PM)
It is not just a question of how much energy is available, it is also a question of how it is distributed and directed.
Energetic consideration are necessary conditions, but not sufficient.
Energy is a scalar quantity.
Yes, the forces must be considered.
The external truss seat failure was vertical below floor 98 in WTC 1.
The pressure of the crushed mass has been proposed, several times now, as the means by which the exterior walls sections were forced apart.
Energetic consideration are necessary conditions, but not sufficient.
Energy is a scalar quantity.
Yes, the forces must be considered.
The external truss seat failure was vertical below floor 98 in WTC 1.
The pressure of the crushed mass has been proposed, several times now, as the means by which the exterior walls sections were forced apart.
QUOTE (lozenge124+Aug 15 2007, 04:40 PM)
It is not just a question of how much energy is available, it is also a question of how it is distributed and directed.
If you consider that the perimeter and core columns were vertical, and that the kinetic energy of the upper block was also vertical - in the same vector direction as gravity - it becomes problematic to explain how the columns could fail at the bolt connections without displaying any bending. Can you push downwards on two vertically bolted columns and break the joint between the two without any column bending?
Not really.
The in-line vertical splices were not as robust as the attachment points of the load bearing horizontal beams in the core. The rapidly descending mass would have exerted significant loads via these members upon the splices.
Arthur
If you consider that the perimeter and core columns were vertical, and that the kinetic energy of the upper block was also vertical - in the same vector direction as gravity - it becomes problematic to explain how the columns could fail at the bolt connections without displaying any bending. Can you push downwards on two vertically bolted columns and break the joint between the two without any column bending?
Not really.
The in-line vertical splices were not as robust as the attachment points of the load bearing horizontal beams in the core. The rapidly descending mass would have exerted significant loads via these members upon the splices.
Arthur
QUOTE
The in-line vertical splices were not as robust as the attachment points of the load bearing horizontal beams in the core. The rapidly descending mass would have exerted significant loads via these members upon the splices.
Something just occurred to me that I haven't seen discussed before.
The core columns had been supporting the upper block immediately prior to the collapse. This was an immense load, which would've compressed the core columns, shortening them by an amount proportional to the load, like a weight being supported by a spring, right?
But that was an awful long spring.
How much compression would that upper block have caused in the core structure? Inches, perhaps?
When the load was dropped, wouldn't that have caused the core to rebound vertically by that same amount?
If one core column broke and the one next to it hadn't broken yet, wouldn't that create a differential moment on the section of floor between the two points where the floor is connected to the two columns?
I'm thinking that perhaps the rebound of the core once it'd dropped it's overburden may have overstressed the floor supports and shattered the concrete floor slab(s).
DBB/Arthur - What sort of displacement(s) would we be looking at?
W.C.Elliot, it is indeed a complex situation to understand what happened with those cores. Don't forgot that all the trusses were welded to it, it is a complex composite structure and those Euler buckling formula's do not apply for such a structure. It is interesting however that (assuming the initial acceleration is about 2g/3) an E1 value of 400MJ can be derived, this is the real energy lost to crush the material between two floors and/or to detach it from the building. It is an extremely important value because it shows that it is not a matter of a total bypass of the core columns. It also does not make sense that they are bypassed because that does not happen in at least 50% of the collapse. The important thing is that we have an empirical value, in fact a measurement of that value. Even if the cores are totally bypassed one must accept that, in spite of the fact that they are bypassed, still 400MJ is consumed/dissipated in the stepwise collapse.
einsteen - Thanks, but I'm pretty sure we're talking about two different things.
As an illustration, there was a case where hundreds of people were playing Tug-of-War with a nylon rope. Stressed beyond the rope's breaking point, it snapped, and the energy stored in the rope caused it to shoot through the hands of the participants, injuring many, and most of them were the ones closest to the breakpoint of the rope.
Visualize the mechanics of the situation, now replace the rope-in-tension with core-columns-in-compression, and replace the ropes-shooting-through-hands phenomenon with core-suddenly-thrusting-upwards-shearing-floor-supports.
This would be easier for me to visualize if I had an estimate of how much total displacement the overburden of the dropping mass was. I'm guessing it may be as much as several inches, but even if it's less, this could help to explain the comminution of the floors' concrete.
As an illustration, there was a case where hundreds of people were playing Tug-of-War with a nylon rope. Stressed beyond the rope's breaking point, it snapped, and the energy stored in the rope caused it to shoot through the hands of the participants, injuring many, and most of them were the ones closest to the breakpoint of the rope.
Visualize the mechanics of the situation, now replace the rope-in-tension with core-columns-in-compression, and replace the ropes-shooting-through-hands phenomenon with core-suddenly-thrusting-upwards-shearing-floor-supports.
This would be easier for me to visualize if I had an estimate of how much total displacement the overburden of the dropping mass was. I'm guessing it may be as much as several inches, but even if it's less, this could help to explain the comminution of the floors' concrete.
I'm sorry, yeah I now knows what rebound means...
That rebound process then should take place at each collision.. Indeed the stepwise collapse implies that the rest of the building is still in the elastic phase, but if the core columns are compressed a little bit there will also be movement of the welds and the attached mass, mass is very slow of course, I don't know man... will be a matter of doing the hard and dirty work, brute calculations....
That rebound process then should take place at each collision.. Indeed the stepwise collapse implies that the rest of the building is still in the elastic phase, but if the core columns are compressed a little bit there will also be movement of the welds and the attached mass, mass is very slow of course, I don't know man... will be a matter of doing the hard and dirty work, brute calculations....
QUOTE (wcelliott+Aug 15 2007, 11:15 PM)
But that was an awful long spring.
How much compression would that upper block have caused in the core structure? Inches, perhaps?
When the load was dropped, wouldn't that have caused the core to rebound vertically by that same amount?
If one core column broke and the one next to it hadn't broken yet, wouldn't that create a differential moment on the section of floor between the two points where the floor is connected to the two columns?
438.3 meters for WTC 1, from the top to the bottom of the lowest sub-basement.
Assuming the elastic limit is at a compression ratio of 0.002, a maximum of 0.877 meters. I estimate about 1/3 of that under normal operating conditions. However, the one degree tilt of the top of WTC 1 just prior to collapse initiation already consumes about 0.55 meters of that limit.
Yes.
Yes.
How much compression would that upper block have caused in the core structure? Inches, perhaps?
When the load was dropped, wouldn't that have caused the core to rebound vertically by that same amount?
If one core column broke and the one next to it hadn't broken yet, wouldn't that create a differential moment on the section of floor between the two points where the floor is connected to the two columns?
438.3 meters for WTC 1, from the top to the bottom of the lowest sub-basement.
Assuming the elastic limit is at a compression ratio of 0.002, a maximum of 0.877 meters. I estimate about 1/3 of that under normal operating conditions. However, the one degree tilt of the top of WTC 1 just prior to collapse initiation already consumes about 0.55 meters of that limit.
Yes.
Yes.
QUOTE (wcelliott+Aug 16 2007, 01:58 PM)
einsteen - Thanks, but I'm pretty sure we're talking about two different things.
As an illustration, there was a case where hundreds of people were playing Tug-of-War with a nylon rope. Stressed beyond the rope's breaking point, it snapped, and the energy stored in the rope caused it to shoot through the hands of the participants, injuring many, and most of them were the ones closest to the breakpoint of the rope.
Visualize the mechanics of the situation, now replace the rope-in-tension with core-columns-in-compression, and replace the ropes-shooting-through-hands phenomenon with core-suddenly-thrusting-upwards-shearing-floor-supports.
This would be easier for me to visualize if I had an estimate of how much total displacement the overburden of the dropping mass was. I'm guessing it may be as much as several inches, but even if it's less, this could help to explain the comminution of the floors' concrete.
That was something that was discussed a while back. I would expect longitudinal, lateral, and torsional waves to be propagating up and down the columns of the towers during collapse. The floor-to-column connections and the column splices might have some ability to withstand longitudinal waves but lateral and torsional waves could easily fracture the connections. Lateral waves were seen going up and down the remnant of the core of WTC1 for a few seconds before it finally collapsed. Some of the splices near the ground level probably failed and caused it to collapse bottom to top.
Similar vibrations were seen on the north perimeter wall of WTC1 near the aircraft impact region down to about the mechanical levels at 75/76 during the first few seconds of collapse. That section of wall wavers and then appears to fall relatively straight down. The vibrations probably caused the splices to fail near the mechanical level.
As an illustration, there was a case where hundreds of people were playing Tug-of-War with a nylon rope. Stressed beyond the rope's breaking point, it snapped, and the energy stored in the rope caused it to shoot through the hands of the participants, injuring many, and most of them were the ones closest to the breakpoint of the rope.
Visualize the mechanics of the situation, now replace the rope-in-tension with core-columns-in-compression, and replace the ropes-shooting-through-hands phenomenon with core-suddenly-thrusting-upwards-shearing-floor-supports.
This would be easier for me to visualize if I had an estimate of how much total displacement the overburden of the dropping mass was. I'm guessing it may be as much as several inches, but even if it's less, this could help to explain the comminution of the floors' concrete.
That was something that was discussed a while back. I would expect longitudinal, lateral, and torsional waves to be propagating up and down the columns of the towers during collapse. The floor-to-column connections and the column splices might have some ability to withstand longitudinal waves but lateral and torsional waves could easily fracture the connections. Lateral waves were seen going up and down the remnant of the core of WTC1 for a few seconds before it finally collapsed. Some of the splices near the ground level probably failed and caused it to collapse bottom to top.
Similar vibrations were seen on the north perimeter wall of WTC1 near the aircraft impact region down to about the mechanical levels at 75/76 during the first few seconds of collapse. That section of wall wavers and then appears to fall relatively straight down. The vibrations probably caused the splices to fail near the mechanical level.
QUOTE (shagster+Aug 16 2007, 04:56 PM)
That was something that was discussed a while back. I would expect longitudinal, lateral, and torsional waves to be propagating up and down the columns of the towers during collapse. The floor-to-column connections and the column splices might have some ability to withstand longitudinal waves but lateral and torsional waves could easily fracture the connections. Lateral waves were seen going up and down the remnant of the core of WTC1 for a few seconds before it finally collapsed. Some of the splices near the ground level probably failed and caused it to collapse bottom to top.
Similar vibrations were seen on the north perimeter wall of WTC1 near the aircraft impact region down to about the mechanical levels at 75/76 during the first few seconds of collapse. That section of wall wavers and then appears to fall relatively straight down. The vibrations probably caused the splices to fail near the mechanical level.
wow. sounds like a controlled demolition.
are these "observed" waves in the all-seeing NIST report? i don't remember reading or hearing anything about fracture waves(elliot, i believe), or waves being OBSERVED.
as the OCT 'progresses', it becomes increasingly(and laughingly desperate) like a 'natural' explanation for a 'artificial' phenomena.
and how about this completely unsupported statement of unfact..."lateral and torsional waves could easily fracture the connections."
see ya 'round, OCT-opus-sees.
Similar vibrations were seen on the north perimeter wall of WTC1 near the aircraft impact region down to about the mechanical levels at 75/76 during the first few seconds of collapse. That section of wall wavers and then appears to fall relatively straight down. The vibrations probably caused the splices to fail near the mechanical level.
wow. sounds like a controlled demolition.
are these "observed" waves in the all-seeing NIST report? i don't remember reading or hearing anything about fracture waves(elliot, i believe), or waves being OBSERVED.
as the OCT 'progresses', it becomes increasingly(and laughingly desperate) like a 'natural' explanation for a 'artificial' phenomena.
and how about this completely unsupported statement of unfact..."lateral and torsional waves could easily fracture the connections."
see ya 'round, OCT-opus-sees.
QUOTE (newton+Aug 16 2007, 11:06 AM)
wow.
shagster observed these in certain videos he watched.
Astaneh mentions in his final report that the vertical connections between core column members were just construction splices. And we know that the exterior wall panels were bolted together, largely falling apart at the bolts.
Wow.
shagster observed these in certain videos he watched.
Astaneh mentions in his final report that the vertical connections between core column members were just construction splices. And we know that the exterior wall panels were bolted together, largely falling apart at the bolts.
Wow.
QUOTE
wow. sounds like a controlled demolition.
Wow, no, it doesn't.
I'd explain it to you if I thought for one moment that you were actually interested in the truth.
For the rest of us, what this implies is that the whole of the base of the core at the point where the upper block load is no longer being borne by the core columns would be acting like a spring under compression that's suddenly had a substantial release of some of its load, so it'll shoot upwards.
The rate that it shoots upwards is inversely proportional to the fraction of the remaining load to the original load, so it increases with floor height. The highest acceleration would be at the floor immediately below the dropped load. Say that the original load at floor X was 31 floors and the load at floor X after the dropped load was 1 floor, I'd expect the acceleration at floor X to be (initially) 31g's, attempting to accelerate floor X to the new position 0.877m/3 higher (about 1 foot). The supports for floor X aren't anywhere near that strong, so they'd fail, reducing the load on the core by one floor's worth, and the process would repeat for the floor below with similar results.
This assumes an instantaneous drop of load, which is, I recognize, unrealistic for the general case, but I'd expect something approaching this condition on at least some of the core columns, which would contribute to the core-side collapse.
The shearing noted wouldn't have been from floor impacts from above shearing them downwards, but would've been from core columns suddenly shooting up a foot, much faster that they could've accelerated the floors. (In the actual case, I'd expect a combination of the two mechanisms, with slower-unloaded core columns getting their floor supports sheared downwards from bagelling and the fast-unloaded core column floor supports getting sheared upwards from the mechanism described above.)
Differentials would've shattered the concrete between the two failure modes.
QUOTE (newton+Aug 16 2007, 06:06 PM)
are these "observed" waves in the all-seeing NIST report? i don't remember reading or hearing anything about fracture waves(elliot, i believe), or waves being OBSERVED.
My 911 folder contains over 1600 files, of course not all wtc related, but I have never have seen these effects, that would also be impossible, per story that is a resolution of 0.028 pixel which is lower than the random noise and fluctuations around. Only indirect effects of it could be observed, not the squibs and some random smoke, it would be a much more homogenous effect. Btw a spring model would not lead to the observed collapse.
My 911 folder contains over 1600 files, of course not all wtc related, but I have never have seen these effects, that would also be impossible, per story that is a resolution of 0.028 pixel which is lower than the random noise and fluctuations around. Only indirect effects of it could be observed, not the squibs and some random smoke, it would be a much more homogenous effect. Btw a spring model would not lead to the observed collapse.
QUOTE (lozenge124+Aug 16 2007, 08:40 AM)
It is not just a question of how much energy is available, it is also a question of how it is distributed and directed.
If you consider that the perimeter and core columns were vertical, and that the kinetic energy of the upper block was also vertical - in the same vector direction as gravity - it becomes problematic to explain how the columns could fail at the bolt connections without displaying any bending. Can you push downwards on two vertically bolted columns and break the joint between the two without any column bending?
Another surprising feature under these considerations is the "floor by floor" progressive nature of the collapse - if the crushing force is vertical, how can it knock out the column bolt connections on one horizontal level (one floor) without causing any damage further down?
To break off the perimeter column sections as described ("bolt failure and truss seat failure", plus progressive collapse) you need a large horizontal force component. There may have been enough energy available as the upper block's potential energy was converted into kinetic energy, but it was mostly directed vertically, and no mechanism has yet been proposed for how this energy could manifest itself in horizontal component forces directed outwards...
Energetic consideration are necessary conditions, but not sufficient.
Not really.
Elastic/Plastic failure only generaly occurs in stress-strain regimes where a significant amount of time is involved (bending takes time).
Brittle failure takes far less time, and is more likely when you apply a large, sudden force over a small surface area.
Somewhere around I have (or had) a bolt from a railway track that was sheared off in an earthquake.
If you consider that the perimeter and core columns were vertical, and that the kinetic energy of the upper block was also vertical - in the same vector direction as gravity - it becomes problematic to explain how the columns could fail at the bolt connections without displaying any bending. Can you push downwards on two vertically bolted columns and break the joint between the two without any column bending?
Another surprising feature under these considerations is the "floor by floor" progressive nature of the collapse - if the crushing force is vertical, how can it knock out the column bolt connections on one horizontal level (one floor) without causing any damage further down?
To break off the perimeter column sections as described ("bolt failure and truss seat failure", plus progressive collapse) you need a large horizontal force component. There may have been enough energy available as the upper block's potential energy was converted into kinetic energy, but it was mostly directed vertically, and no mechanism has yet been proposed for how this energy could manifest itself in horizontal component forces directed outwards...
Energetic consideration are necessary conditions, but not sufficient.
Not really.
Elastic/Plastic failure only generaly occurs in stress-strain regimes where a significant amount of time is involved (bending takes time).
Brittle failure takes far less time, and is more likely when you apply a large, sudden force over a small surface area.
Somewhere around I have (or had) a bolt from a railway track that was sheared off in an earthquake.
Video from the north side of WTC1 shows two sections of perimeter wall just below the aircraft impact region wavering before finally falling about 5 to 6 seconds into the collapse. It shows that the front was able to bypass sections of perimeter wall. The upper block tilted to the south, so it's not surprising that the block missed some sections of the north wall.
Either the wavering of columns broke the splices or the pile of accumulating falling mass pushed outward enough on the columns to break the splices.
The columns of the core remnant of WTC1 showed a similar wavering behavior before the remnant finally collapsed from bottom to top after the end of the main collapse.
This isn't the same as Cherepanov's 'fracture wave' theory. It's a case where unsupported columns many stories high wavered enough to break the column splices.
http://s134.photobucket.com/albums/q91/sha...WTC1NWperi1.flv
Either the wavering of columns broke the splices or the pile of accumulating falling mass pushed outward enough on the columns to break the splices.
The columns of the core remnant of WTC1 showed a similar wavering behavior before the remnant finally collapsed from bottom to top after the end of the main collapse.
This isn't the same as Cherepanov's 'fracture wave' theory. It's a case where unsupported columns many stories high wavered enough to break the column splices.
http://s134.photobucket.com/albums/q91/sha...WTC1NWperi1.flv
NIST looked at the issue of the bolted column splices and stated that a bending of about 1.7 degrees was enough to compromise the bolted splices. A group at MIT came up with a similar value. That's a fairly low angle needed to fail the splices. The splices had strength when the ends of the columns were firmly mated via the bolts. A small amount of bending stretches the bolts and then the ends are no longer firmly mated. The strength of the splice at that point becomes closer to that of the bolts, which is a small fraction of the intended strength of the splice. That failure mode was evident in all the failed splices seen in the rubble.
Just wanted to add this, the Micro-spheres seem to have an organic origin, there are several reactions that can produce them from almost anything that was once composed of living cells including oils used in wood finishes, and bacteria.
They do however point to temperatures in excess of 1400c.
They do however point to temperatures in excess of 1400c.
The Deutsche Bank Building, a steel frame skyscraper has a 7 alarm fire raging for hours
wcbstv.com/topstories/local_story_230171152.html
No collapse.
wcbstv.com/topstories/local_story_230171152.html
No collapse.
So?
The building was VACANT.
Had been vacant for some time and was in the process of being demolished.
Meaning MOST of the fuel (office material) would have long since been removed.
And of course there was no significant damage from a plane impact either.
Arthur
The building was VACANT.
Had been vacant for some time and was in the process of being demolished.
Meaning MOST of the fuel (office material) would have long since been removed.
And of course there was no significant damage from a plane impact either.
Arthur
QUOTE (Chainsaw,+Aug 20 2007, 02:41 AM)
Just wanted to add this, the Micro-spheres seem to have an organic origin, there are several reactions that can produce them from almost anything that was once composed of living cells including oils used in wood finishes, and bacteria.
They do however point to temperatures in excess of 1400c.
Localized contact point temperatures maybe.
They do however point to temperatures in excess of 1400c.
Localized contact point temperatures maybe.
QUOTE (Daru+Aug 19 2007, 10:20 AM)
The Deutsche Bank Building, a steel frame skyscraper has a 7 alarm fire raging for hours
wcbstv.com/topstories/local_story_230171152.html
No collapse.
My car has a gas leak and catches on fire one day. It smolders all day before I put it out. My next car catches on fire and explodes in a few minutes. What in God's name made different results? They're both cars.
You make as much sense as a 20 year old rich girl banging an 80 year old broke d!ck. What the hell?
wcbstv.com/topstories/local_story_230171152.html
No collapse.
My car has a gas leak and catches on fire one day. It smolders all day before I put it out. My next car catches on fire and explodes in a few minutes. What in God's name made different results? They're both cars.
You make as much sense as a 20 year old rich girl banging an 80 year old broke d!ck. What the hell?
QUOTE (Trippy+Aug 19 2007, 06:46 PM)
Localized contact point temperatures maybe.
Exactly, steel oxidation is more likely to create the spheres than aluminum Oxidation, the way to prove they are organic is to forget about the Fe, and the Al and see if the ratio of other elements matches that in organic life.
It is just simple cell biology without those compounds no cell will function, from red blood cells to read tomatoes those elements are all part of cellular chemistry.
Exactly, steel oxidation is more likely to create the spheres than aluminum Oxidation, the way to prove they are organic is to forget about the Fe, and the Al and see if the ratio of other elements matches that in organic life.
It is just simple cell biology without those compounds no cell will function, from red blood cells to read tomatoes those elements are all part of cellular chemistry.
QUOTE (Chainsaw,+Aug 20 2007, 07:47 AM)
Exactly, steel oxidation is more likely to create the spheres than aluminum Oxidation, the way to prove they are organic is to forget about the Fe, and the Al and see if the ratio of other elements matches that in organic life.
It is just simple cell biology without those compounds no cell will function, from red blood cells to read tomatoes those elements are all part of cellular chemistry.
Bare in mind however, the other alternative.
As I pointed out before, what I have seen of the composition is also completely consistent with Stuctural Steel + Duralumin + Gypsum.
It is just simple cell biology without those compounds no cell will function, from red blood cells to read tomatoes those elements are all part of cellular chemistry.
Bare in mind however, the other alternative.
As I pointed out before, what I have seen of the composition is also completely consistent with Stuctural Steel + Duralumin + Gypsum.
I knew someone would bring up the Deutsche Bank.
1) The building was NOT a tube in a tube design. It was a web design which disperses load more evenly.
2) The fires were on the upper floors. The fire affected steel did not have anywhere near the same weight on them as the WTC7.
3) The towers had it's fireproofing removed by on the impact of the planes. Not so for the Deutsche Bank.
4) The fires were being fought which is why 2 firemen died.
6) There was no con ed substation to build the core columns around as with the WTC 7.
7) Those steel beams already had floors removed above them. The steel started with a lighter load before the fire.
1) The building was NOT a tube in a tube design. It was a web design which disperses load more evenly.
2) The fires were on the upper floors. The fire affected steel did not have anywhere near the same weight on them as the WTC7.
3) The towers had it's fireproofing removed by on the impact of the planes. Not so for the Deutsche Bank.
4) The fires were being fought which is why 2 firemen died.
6) There was no con ed substation to build the core columns around as with the WTC 7.
7) Those steel beams already had floors removed above them. The steel started with a lighter load before the fire.
QUOTE
7) Those steel beams already had floors removed above them. The steel started with a lighter load before the fire.
And,
8) It wasn't one of the tallest buildings in the world, so its designer could afford to make it more robust than something 110 stories tall.
9, 10 & 11. A fire can not destroy a steel structure CD style.
QUOTE
9, 10 & 11. A fire can not destroy a steel structure CD style.
They weren't destroyed CD-style. They collapsed from fire AND structural damage from impacts.
daru
I didn't see anywhere in the article any mention of a 757 full of fuel hitting that building setting it on fire all at once or another building falling on it. I don't believe that building was tube in a tube construction either so what is your point, DAru.
Grumpy
I didn't see anywhere in the article any mention of a 757 full of fuel hitting that building setting it on fire all at once or another building falling on it. I don't believe that building was tube in a tube construction either so what is your point, DAru.
Grumpy
I would just add that it was 41-floors but is being dimantled a floor at a time, and is now 26 floors.
QUOTE (Daru+Aug 19 2007, 03:20 PM)
The Deutsche Bank Building, a steel frame skyscraper has a 7 alarm fire raging for hours
wcbstv.com/topstories/local_story_230171152.html
No collapse.
looks like god has built another potent message into the fabric of reality.
awesome .gif.
and, of course, steel frame buildings don't collapse like brittle, fracturing china.
awesome load bearing capacity.
wcbstv.com/topstories/local_story_230171152.html
No collapse.
looks like god has built another potent message into the fabric of reality.
awesome .gif.
and, of course, steel frame buildings don't collapse like brittle, fracturing china.
awesome load bearing capacity.
QUOTE (Trippy+Aug 19 2007, 08:05 PM)
Bare in mind however, the other alternative.
As I pointed out before, what I have seen of the composition is also completely consistent with Stuctural Steel + Duralumin + Gypsum.
Yes it is at temperatures well over 2000c the aluminum oxide must be molten to allow the steel to combine with the aluminum to form the spheres, I just think that 1400c would be an easier temperature range and would occur with virtually any organic.
Then again were only talking over 600c in difference here.
As I pointed out before, what I have seen of the composition is also completely consistent with Stuctural Steel + Duralumin + Gypsum.
Yes it is at temperatures well over 2000c the aluminum oxide must be molten to allow the steel to combine with the aluminum to form the spheres, I just think that 1400c would be an easier temperature range and would occur with virtually any organic.
Then again were only talking over 600c in difference here.
New Haven Coliseum.
http://www.youtube.com/watch?v=RPeNyw1VtIA
It was only a few stories tall but generated a lot of dust at the end of the collapse.
http://www.youtube.com/watch?v=RPeNyw1VtIA
It was only a few stories tall but generated a lot of dust at the end of the collapse.
Trippy:
The WTC micro-spheres appear to contain significant amounts of potassium as well as iron and aluminum. Where does the potassium come from?
The WTC micro-spheres appear to contain significant amounts of potassium as well as iron and aluminum. Where does the potassium come from?
QUOTE (shagster+Aug 20 2007, 01:05 PM)
New Haven Coliseum.
http://www.youtube.com/watch?v=RPeNyw1VtIA
It was only a few stories tall but generated a lot of dust at the end of the collapse.
i would guess the dirt is very dry in that demo.
landmark demo on youtube
count the time of descent. 8 seconds. longer than wtc7, which was taller by 17 stories, or about 150%.
CDI-diots indeed.
http://www.youtube.com/watch?v=RPeNyw1VtIA
It was only a few stories tall but generated a lot of dust at the end of the collapse.
i would guess the dirt is very dry in that demo.
landmark demo on youtube
count the time of descent. 8 seconds. longer than wtc7, which was taller by 17 stories, or about 150%.
CDI-diots indeed.
newton
WTC 7 took over 18 seconds to collapse, of which only the last 6 are visible in the video. The East penthouse collapsed into a huge hole some 12 seconds before that, so where did the hole come from???(hint...from the progressive collapse not seen by the camera, but caught on the siesmic record).
Don't you ever get tired of peeking out through your belly button to see where you are going???
Grumpy
QUOTE
count the time of descent. 8 seconds. longer than wtc7, which was taller by 17 stories, or about 150%.
CDI-diots indeed.
CDI-diots indeed.
WTC 7 took over 18 seconds to collapse, of which only the last 6 are visible in the video. The East penthouse collapsed into a huge hole some 12 seconds before that, so where did the hole come from???(hint...from the progressive collapse not seen by the camera, but caught on the siesmic record).
Don't you ever get tired of peeking out through your belly button to see where you are going???
Grumpy
Eh... they took down the penthouse first ... for whatever reason... then they pulled the building and it fell in 6.5 sec.
QUOTE
looks like god has built another potent message into the fabric of reality.
Brace yourself for this one, newton:
Have you ever noticed how "God" is "dog" spelled backwards?
Kinda makes you think, huh?
DAru
"they" didn't take out anything, the penthouse fell because the building under it WAS GONE, it collapsed more than 10 seconds before the visible collapse shown in the video, DAru.
Grumpy
"they" didn't take out anything, the penthouse fell because the building under it WAS GONE, it collapsed more than 10 seconds before the visible collapse shown in the video, DAru.
Grumpy
QUOTE (Grumpy+Aug 20 2007, 03:01 PM)
newton
WTC 7 took over 18 seconds to collapse, of which only the last 6 are visible in the video. The East penthouse collapsed into a huge hole some 12 seconds before that, so where did the hole come from???(hint...from the progressive collapse not seen by the camera, but caught on the siesmic record).
Don't you ever get tired of peeking out through your belly button to see where you are going???
Grumpy
well, SAYS YOU.
the outer walls of wtc7 fell with ZERO resistance from themselves, or anything else.
if i include the time from the first charges going off(presumably, some things begin to fall, out of sight) until the roof hits the ground, the landmark took from 11 seconds in, 'til 25 seconds in on the video, for a total of fourteen seconds.
daru, the reason they started with the core on tower seven, is so that everything falls in on itself. they clear out the support from the centre, and everything leans in.
WTC 7 took over 18 seconds to collapse, of which only the last 6 are visible in the video. The East penthouse collapsed into a huge hole some 12 seconds before that, so where did the hole come from???(hint...from the progressive collapse not seen by the camera, but caught on the siesmic record).
Don't you ever get tired of peeking out through your belly button to see where you are going???
Grumpy
well, SAYS YOU.
the outer walls of wtc7 fell with ZERO resistance from themselves, or anything else.
if i include the time from the first charges going off(presumably, some things begin to fall, out of sight) until the roof hits the ground, the landmark took from 11 seconds in, 'til 25 seconds in on the video, for a total of fourteen seconds.
daru, the reason they started with the core on tower seven, is so that everything falls in on itself. they clear out the support from the centre, and everything leans in.
newton, meet DAru. Now here's some crayons, go sit at the table and try to keep between the lines. NO, newton, don't eat them!!! I know it looks like an Orange, but you color with them, they taste really bad!!!
Grumpy
Grumpy
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