QUOTE (Chainsaw,+Nov 23 2007, 09:00 PM)
I believe chemical reactions lead to heating producing Charcoal like deposits, those deposits remained hot and auto ignited on exposure to air, in the clean up.
As the clean up progressed new chemical reactions were created for a while, by the disturbance involved in the very clean up operations themselves.
Those could have kept the now hot Carbonized deposits, hot for a long time until they were exposed and auto ignited.
That's a nice description of how an oportunistic fire starts.
Arthur
As the clean up progressed new chemical reactions were created for a while, by the disturbance involved in the very clean up operations themselves.
Those could have kept the now hot Carbonized deposits, hot for a long time until they were exposed and auto ignited.
That's a nice description of how an oportunistic fire starts.
Arthur
QUOTE (adoucette+Nov 24 2007, 02:08 AM)
That's a nice description of how an oportunistic fire starts.
Arthur
The problem Arthur is NEU-FONZE is giving the burn rate for a fire with a continuous burn, at lowest smoldering rate, based on the carbon fuels available, so another mechanism has to be at play, a chemical one extending the fires duration.
Simple insulation of carbon coals can not be at play because the fire is releasing heat, and known though observations to be releasing heat.
So some other reactions have to be adding to the fires to produce extra heat to keep the unburned carbonized deposits at the temperature where when exposed, the carbons they will auto ignite.
What NEU-FONZE is actually saying is that there is something making the fires as you said more oportunistic, causing added heating and allowing the carbonized deposits to remain hot, until exposed.
I know he has been working on finding out the cause of the Oportunistic Carbonized coals problem, it is just not easy, only so much carbon fuel is availiable to be burned and we know that some of it was not consumed from pictures of the cleanup so there is a true deficiet here that can be explained though chemical reactions that also produce heat.
It is just complicated and hard to Quantifiy so NEU-FONZE has just simplified the problem in a search for a solution.
Arthur
The problem Arthur is NEU-FONZE is giving the burn rate for a fire with a continuous burn, at lowest smoldering rate, based on the carbon fuels available, so another mechanism has to be at play, a chemical one extending the fires duration.
Simple insulation of carbon coals can not be at play because the fire is releasing heat, and known though observations to be releasing heat.
So some other reactions have to be adding to the fires to produce extra heat to keep the unburned carbonized deposits at the temperature where when exposed, the carbons they will auto ignite.
What NEU-FONZE is actually saying is that there is something making the fires as you said more oportunistic, causing added heating and allowing the carbonized deposits to remain hot, until exposed.
I know he has been working on finding out the cause of the Oportunistic Carbonized coals problem, it is just not easy, only so much carbon fuel is availiable to be burned and we know that some of it was not consumed from pictures of the cleanup so there is a true deficiet here that can be explained though chemical reactions that also produce heat.
It is just complicated and hard to Quantifiy so NEU-FONZE has just simplified the problem in a search for a solution.
QUOTE (Chainsaw+,Nov 23 2007, 09:41 PM)
The problem Arthur is NEU-FONZE is giving the burn rate for a fire with a continuous burn, at lowest smoldering rate, based on the carbon fuels available, so another mechanism has to be at play, a chemical one extending the fires duration.
No,
Neu is giving an ACCELERATING burn rate. Its LINEAR in speed but its consuming an EXPONENTIAL amount of material as time goes on.
Again, that is NOT what the fires were like.
Consider it this way, as Neu says, a smoldering fire burns at 86 cm per day. But NOW, instead of putting it in a 25 meter heap, and setting fire bottom dead center and letting it burn EVER MORE MATERIAL each day, put that same amount of material in a LINE, 5 meters wide by 5 meters tall. Now start this line smoldering. Ok, now its smoldering on a frontal surface with an area of 25 sq meters. Pretty impressive, but, because its in a LINE, the VOLUME that is consumed per day now remains constant.
In this case, burning at a CONSTANT RATE it will take over 1,300 days to burn up the pile.
Ok, now divide the pile into 15 of these lines, set each one on fire and NOW it will take ~ 90 days for all the material in the 15 lines to be consumed.
But there weren't 15 fires burning the whole time.
So, divide the pile into just 5 of these lines but triple the average burn rate, because there were multiple fires and they weren't just smoldering in the pile.
It still takes 90 days, but at least NOW, we have something that is MUCH more like what actually happened in the pile.
Now as to Neu's second calculation:
The NYFD was in charge that day ,so their chiefs asked the demolition company's if they could get it down fast, and gave permission to do it .
Unfortunately this is just a pile of Bovine Poo that you made up.
There is no evidence that what you claim happened.
Just because it doesn't make sense to you to let the building burn, doesn't mean they didn't.
I have to say, I would find it FAR more incredulous that a demolition company would enter a BURNING building (that would have been burning for HOURS) that had unknown STRUCTURAL damage with a load of HE and det cord and then try to set demolition charges.
Even further, having DONE so, there is no reason that the demolition company personal who risked their lives for the NYFD would then keep their HEROICS SECRET.
We've been through this with you before, do you have ANYTHING NEW?
Arthur
Yes. This does not tally with the time available to prepare WTC7 for CD; and yes, the fact it was on fire compounds atmosphere's assertion to the point of being unbelievable.
Going to the website he gives underscores this. Of the examples of CDI's quick-response times, the best found is the first example, and it is not even close to the situation found at WTC7:
http://www.controlled-demolition.com/default.asp?reqLocId=11
Sheikh A. Alakl Residential and Commercial Center.......
Half of the 17-story Sheikh A. Alakl Apartment Building in Jeddah, Saudi Arabia collapsed when portions of the new reinforced concrete facility were overloaded during final stages of construction. At the request of Bechtel, Controlled Demolition Incorporated’s team mobilized to the site in less than 24 hours, prepared the central-core, flat slab, reinforced concrete structure in another 27 hours and put the balance of the building on the ground with absolute safety just 96 hours after the start of demolition preparations.
In addition, CD expert Danny Jowenko's reactions was one of astonishment when in his interview he learned WTC7 had been on fire that day. He knew it was a CD, and the fire made him all the more certain it had to have been prepped before 9/11.
No,
Neu is giving an ACCELERATING burn rate. Its LINEAR in speed but its consuming an EXPONENTIAL amount of material as time goes on.
Again, that is NOT what the fires were like.
Consider it this way, as Neu says, a smoldering fire burns at 86 cm per day. But NOW, instead of putting it in a 25 meter heap, and setting fire bottom dead center and letting it burn EVER MORE MATERIAL each day, put that same amount of material in a LINE, 5 meters wide by 5 meters tall. Now start this line smoldering. Ok, now its smoldering on a frontal surface with an area of 25 sq meters. Pretty impressive, but, because its in a LINE, the VOLUME that is consumed per day now remains constant.
In this case, burning at a CONSTANT RATE it will take over 1,300 days to burn up the pile.
Ok, now divide the pile into 15 of these lines, set each one on fire and NOW it will take ~ 90 days for all the material in the 15 lines to be consumed.
But there weren't 15 fires burning the whole time.
So, divide the pile into just 5 of these lines but triple the average burn rate, because there were multiple fires and they weren't just smoldering in the pile.
It still takes 90 days, but at least NOW, we have something that is MUCH more like what actually happened in the pile.
Now as to Neu's second calculation:
QUOTE (Neu+)
NIST estimate that there was initially about 50,000 kg of combustible material on each floor of WTC 1 & 2. If we assume that material from about 5 floors was consumed before the Towers collapsed, about 5,250,000 kg of “fuel” was initially available within the rubble from each Tower. This fuel, burning at a rate of 1.6 kg/s, would therefore be able to sustain the rubble pile fires for {5,250,000/1.6} seconds or 38 days.
Well first of all, he under estimates the fuel load. NIST assumed 4 lbs per sq ft for the 30,000 sq ft of tenent spaces. (they admit this is LIGHT compared to other building studies, but they were ONLY concerned with the tennent floors that were on fire in the WTC, not the entire building)
But still, 30,000 X 4 = 120,000 / 2.2 lbs/kg = 54,545 kg X 105 floors = 5,727,272 kg * 2= 11,454,545 kg / 1.6 kg/s = 7,159,090 seconds = 82 days, add in the excess material from the Marriott hotel, and the 6 subfloors and that's more like it.
Arthur
Well first of all, he under estimates the fuel load. NIST assumed 4 lbs per sq ft for the 30,000 sq ft of tenent spaces. (they admit this is LIGHT compared to other building studies, but they were ONLY concerned with the tennent floors that were on fire in the WTC, not the entire building)
But still, 30,000 X 4 = 120,000 / 2.2 lbs/kg = 54,545 kg X 105 floors = 5,727,272 kg * 2= 11,454,545 kg / 1.6 kg/s = 7,159,090 seconds = 82 days, add in the excess material from the Marriott hotel, and the 6 subfloors and that's more like it.
Arthur
QUOTE (adoucette+Sep 30 2007, 03:02 PM)
Well in essense you are, because you are claiming the explosives were planted after both towers came down so they could have safer access to the site for rescue operations.
But, after the towers came down the entire surrounding area was evacuated and access was controlled by the NYPD and FDNY.
Of course the Demolition company people would have had to be let in and they would have first had to pull strings with the BATF to get permission to obtain that much high explosives.
So, NO, they couldn't have gotten explosives to the building nor planted/wired them that morning without the NYPD and FDNY being aware of it.
Arthur
The NYFD was in charge that day ,so their chiefs asked the demolition company's if they could get it down fast, and gave permission to do it . Some of these company's have emergency services to act as fast as possible in situations where buildings are instable due to structural failure caused by earthquakes , explosions ,fires.
I can't post a link to the website of such a company yet .
But this the address with one "w" missing :
ww.controlled-demolition.com/default.asp?reqLocId=11
The fire department chiefs didn't want to loose people for the third time that day, by entering a building that was on fire without being sure it was not going to collapse. If building 7 was the first building on fire that day , they had started to fight the fires, I believe .
If FEMA would have been in charge that day , they probably would have wanted to save the building because of all the government agency offices.
I believe the fire department commanders wanted to save their men and still acted responsible by giving the order to bring it down with explosives .
When you decide to stop fighting the fires in a building that large , you get a completely other situation where something else has to be done . If you don't the situation becomes more and more disastrous. fires will spread through the whole building and you have the risk of an uncontrolled collapse.
I can not find uncontrolled collapses of buildings collapsing within their own footprint , anyone ? The Twin towers prove the chaos of an uncontrolled collapse .
Did they give the order to search for traces of explosives during the removal of the debris? You wont find it when you are not looking for it .
But, after the towers came down the entire surrounding area was evacuated and access was controlled by the NYPD and FDNY.
Of course the Demolition company people would have had to be let in and they would have first had to pull strings with the BATF to get permission to obtain that much high explosives.
So, NO, they couldn't have gotten explosives to the building nor planted/wired them that morning without the NYPD and FDNY being aware of it.
Arthur
The NYFD was in charge that day ,so their chiefs asked the demolition company's if they could get it down fast, and gave permission to do it . Some of these company's have emergency services to act as fast as possible in situations where buildings are instable due to structural failure caused by earthquakes , explosions ,fires.
I can't post a link to the website of such a company yet .
But this the address with one "w" missing :
ww.controlled-demolition.com/default.asp?reqLocId=11
The fire department chiefs didn't want to loose people for the third time that day, by entering a building that was on fire without being sure it was not going to collapse. If building 7 was the first building on fire that day , they had started to fight the fires, I believe .
If FEMA would have been in charge that day , they probably would have wanted to save the building because of all the government agency offices.
I believe the fire department commanders wanted to save their men and still acted responsible by giving the order to bring it down with explosives .
When you decide to stop fighting the fires in a building that large , you get a completely other situation where something else has to be done . If you don't the situation becomes more and more disastrous. fires will spread through the whole building and you have the risk of an uncontrolled collapse.
I can not find uncontrolled collapses of buildings collapsing within their own footprint , anyone ? The Twin towers prove the chaos of an uncontrolled collapse .
Did they give the order to search for traces of explosives during the removal of the debris? You wont find it when you are not looking for it .
Arthur:
No need to totally condemn my calculation without a fair trial! It is very approximate, I admit... It's just a way to get a rough idea of how long the rubble pile fires could burn, and what temperatures were possible.
I agree with you on one point at least! I think my estimate of the total fuel load is too low and if you correct for that, say by doubling it, the calculated burn time is actually quite close to what was observed.
And I agree with Chainsaw that some zones deep in the pile would have been starved for oxygen and simply carbonized the combustible materials. However, the pile was shifting and settling a lot of the time and clean up operations eventually exposed some of these hot spots which could then spontaneously re-ignite.
No need to totally condemn my calculation without a fair trial! It is very approximate, I admit... It's just a way to get a rough idea of how long the rubble pile fires could burn, and what temperatures were possible.
I agree with you on one point at least! I think my estimate of the total fuel load is too low and if you correct for that, say by doubling it, the calculated burn time is actually quite close to what was observed.
And I agree with Chainsaw that some zones deep in the pile would have been starved for oxygen and simply carbonized the combustible materials. However, the pile was shifting and settling a lot of the time and clean up operations eventually exposed some of these hot spots which could then spontaneously re-ignite.
QUOTE (NEU-FONZE+Nov 24 2007, 12:28 PM)
Arthur:
No need to totally condemn my calculation without a fair trial! It is very approximate, I admit... It's just a way to get a rough idea of how long the rubble pile fires could burn, and what temperatures were possible.
I agree with you on one point at least! I think my estimate of the total fuel load is too low and if you correct for that, say by doubling it, the calculated burn time is actually quite close to what was observed.
And I agree with Chainsaw that some zones deep in the pile would have been starved for oxygen and simply carbonized the combustible materials. However, the pile was shifting and settling a lot of the time and clean up operations eventually exposed some of these hot spots which could then spontaneously re-ignite.
NEU-FONZE, I do not think your fuel load can be doubled, since much of the fuel that Arthur mentions is in the lower levels and would be unavailable for common combustion do to the flooding of the bathtubs with water from broken pipes,rain and fire fighting operations.
Didn't water have to be pumped out of the lower levels in the clean up?
Wouldn't that reduce the amount of carbon fuels available for combustion and increase the likely hood of Metal-Chloride reactions?
That is one of the things that I looked at when trying to estimate the amount of fuels and duration of the fires in the debris pile.
I would appreciate and answer from anyone who has the answer to that question
Thank you.
No need to totally condemn my calculation without a fair trial! It is very approximate, I admit... It's just a way to get a rough idea of how long the rubble pile fires could burn, and what temperatures were possible.
I agree with you on one point at least! I think my estimate of the total fuel load is too low and if you correct for that, say by doubling it, the calculated burn time is actually quite close to what was observed.
And I agree with Chainsaw that some zones deep in the pile would have been starved for oxygen and simply carbonized the combustible materials. However, the pile was shifting and settling a lot of the time and clean up operations eventually exposed some of these hot spots which could then spontaneously re-ignite.
NEU-FONZE, I do not think your fuel load can be doubled, since much of the fuel that Arthur mentions is in the lower levels and would be unavailable for common combustion do to the flooding of the bathtubs with water from broken pipes,rain and fire fighting operations.
Didn't water have to be pumped out of the lower levels in the clean up?
Wouldn't that reduce the amount of carbon fuels available for combustion and increase the likely hood of Metal-Chloride reactions?
That is one of the things that I looked at when trying to estimate the amount of fuels and duration of the fires in the debris pile.
I would appreciate and answer from anyone who has the answer to that question
Thank you.
QUOTE (Chainsaw+,Nov 24 2007, 07:48 AM)
I do not think your fuel load can be doubled, since much of the fuel that Arthur mentions is in the lower levels and would be unavailable for common combustion do to the flooding of the bathtubs with water from broken pipes,rain and fire fighting operations.
No, Neu made a simple error in his estimation process, he figured out the amount of fuel for just one tower, but then forgot to double it.
This calculation:
30,000 sq ft of tennent space per floor X 4 lbs per sq ft = 120,000 lbs per floor / 2.2 lbs/kg = 54,545 kg X 105 floors = 5,727,272 kg * 2 towers = 11,454,545 kg / burn rate of 1.6 kg/second = 7,159,090 seconds / 86,400 seconds per day = 82 days,
Is for both towers.
It does NOT include the material in the Marriott hotel, the underground shopping levels, or the WTC 5 and WTC 6 buildings/contents.
Arthur
No, Neu made a simple error in his estimation process, he figured out the amount of fuel for just one tower, but then forgot to double it.
This calculation:
30,000 sq ft of tennent space per floor X 4 lbs per sq ft = 120,000 lbs per floor / 2.2 lbs/kg = 54,545 kg X 105 floors = 5,727,272 kg * 2 towers = 11,454,545 kg / burn rate of 1.6 kg/second = 7,159,090 seconds / 86,400 seconds per day = 82 days,
Is for both towers.
It does NOT include the material in the Marriott hotel, the underground shopping levels, or the WTC 5 and WTC 6 buildings/contents.
Arthur
QUOTE (NEU-FONZE+Nov 24 2007, 07:28 AM)
Arthur:
No need to totally condemn my calculation without a fair trial! It is very approximate, I admit... It's just a way to get a rough idea of how long the rubble pile fires could burn, and what temperatures were possible.
I agree with you on one point at least! I think my estimate of the total fuel load is too low and if you correct for that, say by doubling it, the calculated burn time is actually quite close to what was observed.
And I agree with Chainsaw that some zones deep in the pile would have been starved for oxygen and simply carbonized the combustible materials. However, the pile was shifting and settling a lot of the time and clean up operations eventually exposed some of these hot spots which could then spontaneously re-ignite.
As you can see, I didn't condem your calculation of the amount of fuel per tower.
As to you then estimating that it burned at a constant linear rate but also consumed an INCREASING VOLUME per day, such that on the last day it would burn more in ONE MINUTE than it would in the entire first day, over 3,200 cubic meters of material.
YES, Neu, that is TOTALLY WITHOUT MERIT, and I'm surprised that you even consider postulating that there was an EXPONENTIAL quantity of material being consumed by day.
That most definately does not agree with the observations.
Arthur
No need to totally condemn my calculation without a fair trial! It is very approximate, I admit... It's just a way to get a rough idea of how long the rubble pile fires could burn, and what temperatures were possible.
I agree with you on one point at least! I think my estimate of the total fuel load is too low and if you correct for that, say by doubling it, the calculated burn time is actually quite close to what was observed.
And I agree with Chainsaw that some zones deep in the pile would have been starved for oxygen and simply carbonized the combustible materials. However, the pile was shifting and settling a lot of the time and clean up operations eventually exposed some of these hot spots which could then spontaneously re-ignite.
As you can see, I didn't condem your calculation of the amount of fuel per tower.
As to you then estimating that it burned at a constant linear rate but also consumed an INCREASING VOLUME per day, such that on the last day it would burn more in ONE MINUTE than it would in the entire first day, over 3,200 cubic meters of material.
YES, Neu, that is TOTALLY WITHOUT MERIT, and I'm surprised that you even consider postulating that there was an EXPONENTIAL quantity of material being consumed by day.
That most definately does not agree with the observations.
Arthur
QUOTE (atmosphere+Nov 24 2007, 07:09 AM)
The NYFD was in charge that day ,so their chiefs asked the demolition company's if they could get it down fast, and gave permission to do it .
Unfortunately this is just a pile of Bovine Poo that you made up.
There is no evidence that what you claim happened.
Just because it doesn't make sense to you to let the building burn, doesn't mean they didn't.
I have to say, I would find it FAR more incredulous that a demolition company would enter a BURNING building (that would have been burning for HOURS) that had unknown STRUCTURAL damage with a load of HE and det cord and then try to set demolition charges.
Even further, having DONE so, there is no reason that the demolition company personal who risked their lives for the NYFD would then keep their HEROICS SECRET.
We've been through this with you before, do you have ANYTHING NEW?
Arthur
Unfortunately this is just a pile of Bovine Poo that you made up.
There is no evidence that what you claim happened.
Just because it doesn't make sense to you to let the building burn, doesn't mean they didn't.
I have to say, I would find it FAR more incredulous that a demolition company would enter a BURNING building (that would have been burning for HOURS) that had unknown STRUCTURAL damage with a load of HE and det cord and then try to set demolition charges.
Even further, having DONE so, there is no reason that the demolition company personal who risked their lives for the NYFD would then keep their HEROICS SECRET.
We've been through this with you before, do you have ANYTHING NEW?
Arthur
Arthur:
I think you misunderstood my calculation. I did NOT claim an increasing rate of combustion. I postulated a constant burn rate of 1.6 kg/seconds for the entire duration of the rubble pile fires. The smoldering front advances at a constant rate too, just like a burning cigarette. There would be smoldering bands moving through the rubble pile, but the amount of material burning at a given time would be constant.
Chainsaw:
I did forget to include two towers in my calculation... But I agree that the combustion process was undoubtedly more than a simple hydrocarbon/cellulosics fire. There was HCl gas comming off the rubble pile for days after 9/11, probably as the result of PVC pyrolysis. The towers contained tons of PVC on every floor. Prof. Cahill from UC Davis reported metal chloride aerosols in air particulate samples well into October 2001 I believe.
There was also the blast furnace equilibrium reaction:
3Fe + 4H2O <-> Fe3O4 + 4H2
and similar reactions involving Al.
I think you misunderstood my calculation. I did NOT claim an increasing rate of combustion. I postulated a constant burn rate of 1.6 kg/seconds for the entire duration of the rubble pile fires. The smoldering front advances at a constant rate too, just like a burning cigarette. There would be smoldering bands moving through the rubble pile, but the amount of material burning at a given time would be constant.
Chainsaw:
I did forget to include two towers in my calculation... But I agree that the combustion process was undoubtedly more than a simple hydrocarbon/cellulosics fire. There was HCl gas comming off the rubble pile for days after 9/11, probably as the result of PVC pyrolysis. The towers contained tons of PVC on every floor. Prof. Cahill from UC Davis reported metal chloride aerosols in air particulate samples well into October 2001 I believe.
There was also the blast furnace equilibrium reaction:
3Fe + 4H2O <-> Fe3O4 + 4H2
and similar reactions involving Al.
QUOTE (adoucette+Nov 24 2007, 07:07 AM)
QUOTE (atmosphere @ Nov 24 2007+ 07:09 AM)
The NYFD was in charge that day ,so their chiefs asked the demolition company's if they could get it down fast, and gave permission to do it .
Unfortunately this is just a pile of Bovine Poo that you made up.
There is no evidence that what you claim happened.
Just because it doesn't make sense to you to let the building burn, doesn't mean they didn't.
I have to say, I would find it FAR more incredulous that a demolition company would enter a BURNING building (that would have been burning for HOURS) that had unknown STRUCTURAL damage with a load of HE and det cord and then try to set demolition charges.
Even further, having DONE so, there is no reason that the demolition company personal who risked their lives for the NYFD would then keep their HEROICS SECRET.
We've been through this with you before, do you have ANYTHING NEW?
Arthur
Yes. This does not tally with the time available to prepare WTC7 for CD; and yes, the fact it was on fire compounds atmosphere's assertion to the point of being unbelievable.
Going to the website he gives underscores this. Of the examples of CDI's quick-response times, the best found is the first example, and it is not even close to the situation found at WTC7:
http://www.controlled-demolition.com/default.asp?reqLocId=11
Sheikh A. Alakl Residential and Commercial Center.......
Half of the 17-story Sheikh A. Alakl Apartment Building in Jeddah, Saudi Arabia collapsed when portions of the new reinforced concrete facility were overloaded during final stages of construction. At the request of Bechtel, Controlled Demolition Incorporated’s team mobilized to the site in less than 24 hours, prepared the central-core, flat slab, reinforced concrete structure in another 27 hours and put the balance of the building on the ground with absolute safety just 96 hours after the start of demolition preparations.
In addition, CD expert Danny Jowenko's reactions was one of astonishment when in his interview he learned WTC7 had been on fire that day. He knew it was a CD, and the fire made him all the more certain it had to have been prepped before 9/11.
QUOTE (NEU-FONZE+Nov 24 2007, 11:22 AM)
I think you misunderstood my calculation. I did NOT claim an increasing rate of combustion. I postulated a constant burn rate of 1.6 kg/seconds for the entire duration of the rubble pile fires. The smoldering front advances at a constant rate too, just like a burning cigarette. There would be smoldering bands moving through the rubble pile, but the amount of material burning at a given time would be constant.
I didn't have a problem with your 1.6 kg/s, in fact I don't have a problem with most of the rubble pile analysis you've done.
But as to the smoldering front, you use the LINEAR example of a cigarette, but then your error came when you applied it to the bottom dead center of a half globe. This results, with a constant rate of flame propagation from the center, but because the flame is now consuming an ever expanding flame front, it results in an EXPONENTIAL increase in the amount of fuel burnt each day.
If you think my analysis is wrong, then simply explain how a fire burning at 86 cm per day could consume a 25 meter high pile if it DIDN'T consume more of the fuel each day.
Rather dull reading, but perhaps somebody will care to graph the measured and calculated drops versus time.
Editied to add: the clculated drops appear to have a systematic bias of -0.19 meters.
I'll check further and fix it tomorrow.
A demolition team could easily entered the building on the first couple of floors and the basement , there were no fires there !!! Also the fires just started that morning.
For fire fighters it was much more risky to do their job because the fires where localized around the areas where debris entered. They could be hit by falling debris or even face floors collapsing .
Heat and smoke go up ,which means that the basement and the first floors could be entered without any problems. They didn't tell Jowenko this in the interview.
Until this day he's even more convinced of a the controlled demolition of WTC 7 , after talking to other specialist and looking into all available information. Jowenko's work on video is even presented on the implosion world website , so I assume he knows some people over there. He says "American demolition company's can not speak the truth . When they do their history . Also the US government is an important costumer for those company's ,as can be concluded from the "controlled demolition " website . By the Way Jowenko is not the only European explosives expert having problems with the official story about WTC 7 . They do agree with the NIST report about the collapses of the towers. You can't blame them for being conspiracy theorist.
An American demolition team managed to get a job in Saudi Arabia done in a very short time. Most of the time was wasted in bringing their men and equipment on the scene. At 9/11 demolition teams rushed to the scene as soon as the first plane crashed into one of the towers. I believe they had the possibility to bring down WTC 7 in a couple of hours . You cant compare controlled demolitions under normal conditions with the situation at 9/11 .
Jowenko describes how it can be done in very short time . He still sticks to his comment's ( can be watched on You-tube) to this day , and still wants to answer questions about it. Just give him a call !
Do you have his number, I would like to discuss perimeters with him.
-Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree?
Yes, but then one has to have people WILLING to go into a DAMAGED/BURNING building and PLACE the explosives and wire them so they go off at the exact same time. NO ONE saw this happen and NONE of the people who supposedly did this HEROIC act have mentioned it (for NO apparent reason)
Finally, setting the explosives on one floor to cause the building to collapse would make ONE HECK OF A BIG BANG when they went off, something that is MISSING from the videos of the collapse and from the eyewitness testimony of the people who were there at the collapse.
-Fact is WTC 7 had relatively few columns
Not really, it had a floor area of almost an ACRE.
If it was a CD it would have been the LARGEST CD in history.
Which you claim was done in the SHORTEST time in CD history.
And in a Damaged/Burning building as well.
-fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
All true, but SO WHAT?
- Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
NO, it didn't.
It had a SUPERFICAL appearance of a controlled demolition.
It was not preceeded by a lot of men entering the building for days and days stringing explosives and det cord as ALL other CDs are.
The building was burning out of control for 7 hours like no other CD.
There were no Shockwave sounds from all the HE going off.
There was no high speed ejecta from the HE prior to the collapse.
The collapse took a long time (~ 18 secs, with the damage spreading through the structure relatively slowly well before the final curtain wall came down) much more indicitive of a progressive strutural collapse (IMHO) than a HE induced CD (particularly if the CD has to be hurried because of the building conditions).
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are my claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
That's apparently coming this spring.
There will be a public comment period on a draft report prior to that.
The current LACK of the NIST report on the WTC 7 collapse is NOT evidence of a CD though.
The WTC Tower steel, because they were building two almost identical buildings, and because the gross dimensions remained the same as you went up but the cross sections got smaller, was stamped with a building/floor code.
Hence one could tell from the stamp that it was WTC 1 or 2 steel.
There was no such stamp on the WTC 7 steel, thus the identification of steel once it left the site was problematic. I suspect this issue will be covered in the final WTC 7 report.
As to Jowenko, has HE written a peer reviewed paper explaining why he's CERTAIN it was CD? I must admit, all I've heard is his video and that is not at all convincing.
Your claim ISN'T as wild as claiming that explosives were planted before 9/11. Considering the building burnt for 7 hours out of control, that idea is so dumb it hardly warrents comment and you will only find your typical fringe loonies who will publicly support pre-planted explosives in WTC 7.
Arthur
-Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree?
-Fact is WTC 7 had relatively few columns
-fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
- Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are my claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree? [U] All you have to do is take out the weak cantilever beam structure, [/U]-Fact is WTC 7 had relatively few columns
Again the cantilever beam structure is all that has to be taken out.-
fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
Wrong there were signs of the building leaning to wards the damaged side near world trade 6
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
[U]True but not really a concern as most of the structures were evacuated and most were already damaged, setting off charges in a building before doing a full damage assessment.
IS Like going into a rocket ship that has a leaking hydrogen tank after the main engines are ignited, it is just dumb. [/U]
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
Fact is diesel fuel flowing down elevator shafts runs to the lowest part where there were electrical transformers that were energized and could possibly short. -
Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
[B]That is true but doesn't point to controlled demolition all that points to is lack of a peer reviewed paper![/B]A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
There is some, I believe however building 7 was not even considered important in early investigations because of cause and effect perimeters. Building 7 was only treated as a curiosity in the inital investigation because no lives were lost in that building, and if the towers never fell it would not have been damaged at all reguardless of anything done after! Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are mI do not believe he acturately understands the conditions that were in the buildings. y claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
I believe it is wild to believe the explosives were planted at all. [/U]
I solved the crush-up diffeq for the case of F/m being a constant and then expressing resistive force F as the ratio E1/h.
I've also used numerical solutions for the crush-up equation and a discrete algebraic model.
Cool, doesn't that give a constant effective acceleration? Maybe a small correction then should be added. I remember that you did a lot of work in the past, are you ever going to put that online at a central point ? I also hope to see DBBs work once somewhere.
ps.
I posted this before reading your latest posts, yeah I once wrote a similar relation (for constant acceleration) between E1,h,m,g, DBB found the 400MJ surprisingly good, because compaction was ignored.
E1=0 J/kg => T=5.475 seconds
E1/m=289 J/kg => T=6.504 seconds
E1/m=324 J/kg => T=6.771 seconds
There's a discrepancy. For E1=0, the duration for a crush up of 47 stories should be 6.02 seconds.
t = sqrt(2*H/g) = sqrt(2*47*3.78/9.81) = 6.02 s
For higher values of E1/m the result becomes complex which physically means that the collapse is arrested at a certain point, that would lead to a theoretical maximum equal to 6.771 seconds. I'm currently not sure about this, no time to think, the math says it.
That's not necessarily true. There are cases where the total collapse duration can be longer than the case for where the collapse just barely goes to completion at the top story. The crush-up may not go to completion when E1 is large enough, but it can still have a longer duration than for the case where it just barely goes to completion.
That may sound counter-intuitive, but if you solve the algebraic models or the crush-up diffeq for some various values of E1, it turns out to be the case.
I agree completely, and would add that nothing gets done in the real world without contracts in-place, especially regarding liabilities for injuries and potential loss of lives. While it's conceivable that one could find ninja-commando-fairies willing to risk their lives for marginal motives like trying to implode a burning building that's bound to collapse sooner or later, I've never heard of lawyers willing to draw up contracts limiting liabilities for that sort of thing in the time-frames available. If a lawyer rushes a contract, he risks losing his license to practice law.
While there may be heroes willing to risk their lives to plant explosives in a burning building, I doubt that there are lawyers willing to risk disbarment for participating in the same effort. (And remember, lawyers charge by the hour, so how much would they be paid for their efforts?) Without a contract, there would be no legal means of paying the ninja-commando-fairies, so that, alone, means it just didn't happen.
I agree completely, and would add that nothing gets done in the real world without contracts in-place, especially regarding liabilities for injuries and potential loss of lives. While it's conceivable that one could find ninja-commando-fairies willing to risk their lives for marginal motives like trying to implode a burning building that's bound to collapse sooner or later, I've never heard of lawyers willing to draw up contracts limiting liabilities for that sort of thing in the time-frames available. If a lawyer rushes a contract, he risks losing his license to practice law.
While there may be heroes willing to risk their lives to plant explosives in a burning building, I doubt that there are lawyers willing to risk disbarment for participating in the same effort. (And remember, lawyers charge by the hour, so how much would they be paid for their efforts?) Without a contract, there would be no legal means of paying the ninja-commando-fairies, so that, alone, means it just didn't happen.
Heroes do not go in burning buildings unless it is to save lives, not to blow up unoccupied buildings, that are collapsing in on themselves.
When the site is evacuated, and the pull comment is clearly pulling back the fire fighters trying to contain the fire from the outside of the building.
Saving lives that day was paramount not Building demolitions.
I tested both the Idea of preplanted charges and setting charges after the collapse of the towers, the explosive conditions present make it so stupid that it is not worth commenting on further.
An explosion of Carbons or diesel fuel vapor can set the charges off while your packing the charges inside the buildings in your own hands.
The emergency generators running, negate radio controls, detcord is a no no in that situation. Some one un noticed by all would have had to run wires to the detonator, or stayed behind and set off the charges.
Most people negate that there was an unknown amount of electromagnetic energy in that building, and that radio detonators can be triggered by that alone.
The situation is one that I know I would only undertake if It were to save lives not property, property can be replaced your life can not only insane and crazy people risk their life for Property.
I think we're in complete agreement that the whole notion is ludicrous, I was merely pointing out that while there may be insane/crazy people willing to risk their lives for a pointless venture (collapsing a building already in the process of collapsing on its own), that the concept also presumes that people could find lawyers willing to risk disbarment to draw up a hastily-conceived contract to implement an ill-conceived notion, making it doubly improbable.
Heroic explosives experts, maybe.
Heroic lawyers, never in a million years.
Edited:
I think that you mean that when the velocity is near zero, say 0.1 m/s and E1 is fitted in a way that it stops at the next story with v=0 then the time is h/0.05, I think that is true, but if the collapse is rapid in the beginning then that will not happen I think
I ran my algebraic crush-up model for WTC7 where the mass per story is the same for all stories and equal to what Greening was using per story (510E6 kg / 110). E1 is considered the same for all stories.
For E1=1.85 GJ, the collapse duration is 7.2 s. The crush-up is just barely arrested at the top of the building. E1/m at the ground level is 8.5 J/kg.
For E1=3 GJ, the duration is 8.3 s. The collapse is arrested at the 44th story. Even though the collapse didn't go to completion, the duration is longer than 7.2 s. E1/m at the ground level is 13.8 J/kg.
For E1=1 GJ, the collapse goes to completion and the duration is 6.6 s. E1/m at the ground level is 4.6 J/kg.
The continuous model using diffeq gives similar but slightly longer durations. I can post some of the displacement and velocity curves for the diffeq solution if anyone is interested.
I didn't have a problem with your 1.6 kg/s, in fact I don't have a problem with most of the rubble pile analysis you've done.
But as to the smoldering front, you use the LINEAR example of a cigarette, but then your error came when you applied it to the bottom dead center of a half globe. This results, with a constant rate of flame propagation from the center, but because the flame is now consuming an ever expanding flame front, it results in an EXPONENTIAL increase in the amount of fuel burnt each day.
If you think my analysis is wrong, then simply explain how a fire burning at 86 cm per day could consume a 25 meter high pile if it DIDN'T consume more of the fuel each day.
QUOTE (Neu+)
the smoldering of compressed cellulose-based material proceeds at very consistent rates in the range 10^-3 cm/s. This implies that a 25-meter high rubble pile, rich in cellulose-based fuel, could burn in a smoldering fire lasting approximately 29 days!
DAY Burn Dist. Tot M^3 M^3 burnt per day
01 00.86 ....1 ...0
02 01.73 ...11 ...9
03 02.59 ...36 ..26
04 03.46 ...86 ..50
05 04.32 ..169 ..82
06 05.18 ..292 .123
07 06.05 ..463 .172
08 06.91 ..692 .228
09 07.78 ..985 .293
10 08.64 .1351 .366
11 09.50 .1798 .447
12 10.37 .2334 .536
13 11.23 .2968 .634
14 12.10 .3707 .739
15 12.96 .4559 .852
16 13.82 .5533 .974
17 14.69 .6636 1104
18 15.55 .7878 1241
19 16.42 .9265 1387
20 17.28 10806 1541
21 18.14 12510 1703
22 19.01 14383 1874
23 19.87 16435 2052
24 20.74 18673 2238
25 21.60 21106 2433
26 22.46 23741 2635
27 23.33 26588 2846
28 24.19 29652 3065
29 25.06 32944 3292
It was a simple error, don't get bent out of shape over it.
Arthur
CODE
DAY Burn Dist. Tot M^3 M^3 burnt per day
01 00.86 ....1 ...0
02 01.73 ...11 ...9
03 02.59 ...36 ..26
04 03.46 ...86 ..50
05 04.32 ..169 ..82
06 05.18 ..292 .123
07 06.05 ..463 .172
08 06.91 ..692 .228
09 07.78 ..985 .293
10 08.64 .1351 .366
11 09.50 .1798 .447
12 10.37 .2334 .536
13 11.23 .2968 .634
14 12.10 .3707 .739
15 12.96 .4559 .852
16 13.82 .5533 .974
17 14.69 .6636 1104
18 15.55 .7878 1241
19 16.42 .9265 1387
20 17.28 10806 1541
21 18.14 12510 1703
22 19.01 14383 1874
23 19.87 16435 2052
24 20.74 18673 2238
25 21.60 21106 2433
26 22.46 23741 2635
27 23.33 26588 2846
28 24.19 29652 3065
29 25.06 32944 3292
It was a simple error, don't get bent out of shape over it.
Arthur
Arthur:
My rubble pile smoldering model IS like a cigarette! I have a smoldering front in the rubble pile burning DOWN at a rate of 10^-3 cm per second. So in one day it burns down a distance of 60 x 60 x 24 x 10^-3 cm = 0.864 meters. On day 2 it burns down another 0.864 meters and so on. Hence, after 29 days it has burned a distance of 29 x 0.864 meters or 25 meters.
My rubble pile smoldering model IS like a cigarette! I have a smoldering front in the rubble pile burning DOWN at a rate of 10^-3 cm per second. So in one day it burns down a distance of 60 x 60 x 24 x 10^-3 cm = 0.864 meters. On day 2 it burns down another 0.864 meters and so on. Hence, after 29 days it has burned a distance of 29 x 0.864 meters or 25 meters.
QUOTE (NEU-FONZE+Nov 24 2007, 04:22 PM)
Arthur:
I think you misunderstood my calculation. I did NOT claim an increasing rate of combustion. I postulated a constant burn rate of 1.6 kg/seconds for the entire duration of the rubble pile fires. The smoldering front advances at a constant rate too, just like a burning cigarette. There would be smoldering bands moving through the rubble pile, but the amount of material burning at a given time would be constant.
Chainsaw:
I did forget to include two towers in my calculation... But I agree that the combustion process was undoubtedly more than a simple hydrocarbon/cellulosics fire. There was HCl gas comming off the rubble pile for days after 9/11, probably as the result of PVC pyrolysis. The towers contained tons of PVC on every floor. Prof. Cahill from UC Davis reported metal chloride aerosols in air particulate samples well into October 2001 I believe.
There was also the blast furnace equilibrium reaction:
3Fe + 4H2O <-> Fe3O4 + 4H2
and similar reactions involving Al.
NEU-FONZE & Arthur,
Do not worry about the fires, the fires were multi front fires each tower can in fact be seen as a separate fire, Adding them together only increases the fuel available for the total pile and we also do not know the exact fuel consumed in the fire in the pile or before the buildings fell all we have is an estimate.
I am going with what we do know from NEU-FONZE said Prof. Cahill from UC Davis he has the only true record of the types of reactions going on in the fire.
Assumptions of how much carbon based fuels there were are worthless because the burn rate does not matter if other reactions can cause carbonation as well as heat.
Auto ignition effects in that scenario could last for weeks or months practically with no carbon Combustion taking place at all.
Any comparisons of carbon fuels is simply a meaningless attempt to prove one point or another while the air data shows that reactions that produce heat and do not involve carbons were occurring.
To argue the point of carbon I have found though experimental data is pointless the rate varies so much dependent on what other reactions are taking place.
There is no way to know the fire behavior, in the piles rough assumptions is all that are possible. The weather even effects the reactions the amount of H2O to react with the chlorides, metals, and to produce this reaction, 3Fe + 4H2O <-> Fe3O4 + 4H2.
Does anyone here want to study the weather data and go over the given rainfall on the pile for each day, I know I do not want to take the time to do that.
Rain does not cool the fire in that environment it increases the carbonization and Chloride effects and increase heat in the rubble pile though in creased release of the energy in the metals, and other reactants in the rubble pile.
Only better air data could tell us the exact rate of combustion by products, that would give us a day by day rate, of combustion, and that data is not available.
This point is not really worth arguing because neither contention can actually be Quantified!
Only a day by day collection of CO2 Data, collected above and around the fires would lead to anything that could even remotely be Quantified.
I do not believe such data exists.
Were arguing at this point without the data a really mute point.
Sorry to Rant I just think it is better to go with known data-and experimental data, than estimates of what could have been, Rather than what was.
I think you misunderstood my calculation. I did NOT claim an increasing rate of combustion. I postulated a constant burn rate of 1.6 kg/seconds for the entire duration of the rubble pile fires. The smoldering front advances at a constant rate too, just like a burning cigarette. There would be smoldering bands moving through the rubble pile, but the amount of material burning at a given time would be constant.
Chainsaw:
I did forget to include two towers in my calculation... But I agree that the combustion process was undoubtedly more than a simple hydrocarbon/cellulosics fire. There was HCl gas comming off the rubble pile for days after 9/11, probably as the result of PVC pyrolysis. The towers contained tons of PVC on every floor. Prof. Cahill from UC Davis reported metal chloride aerosols in air particulate samples well into October 2001 I believe.
There was also the blast furnace equilibrium reaction:
3Fe + 4H2O <-> Fe3O4 + 4H2
and similar reactions involving Al.
NEU-FONZE & Arthur,
Do not worry about the fires, the fires were multi front fires each tower can in fact be seen as a separate fire, Adding them together only increases the fuel available for the total pile and we also do not know the exact fuel consumed in the fire in the pile or before the buildings fell all we have is an estimate.
I am going with what we do know from NEU-FONZE said Prof. Cahill from UC Davis he has the only true record of the types of reactions going on in the fire.
Assumptions of how much carbon based fuels there were are worthless because the burn rate does not matter if other reactions can cause carbonation as well as heat.
Auto ignition effects in that scenario could last for weeks or months practically with no carbon Combustion taking place at all.
Any comparisons of carbon fuels is simply a meaningless attempt to prove one point or another while the air data shows that reactions that produce heat and do not involve carbons were occurring.
To argue the point of carbon I have found though experimental data is pointless the rate varies so much dependent on what other reactions are taking place.
There is no way to know the fire behavior, in the piles rough assumptions is all that are possible. The weather even effects the reactions the amount of H2O to react with the chlorides, metals, and to produce this reaction, 3Fe + 4H2O <-> Fe3O4 + 4H2.
Does anyone here want to study the weather data and go over the given rainfall on the pile for each day, I know I do not want to take the time to do that.
Rain does not cool the fire in that environment it increases the carbonization and Chloride effects and increase heat in the rubble pile though in creased release of the energy in the metals, and other reactants in the rubble pile.
Only better air data could tell us the exact rate of combustion by products, that would give us a day by day rate, of combustion, and that data is not available.
This point is not really worth arguing because neither contention can actually be Quantified!
Only a day by day collection of CO2 Data, collected above and around the fires would lead to anything that could even remotely be Quantified.
I do not believe such data exists.
Were arguing at this point without the data a really mute point.
Sorry to Rant I just think it is better to go with known data-and experimental data, than estimates of what could have been, Rather than what was.
To correct a post of yesterday:
F(Z,S) = k*Z*S
To correct misconceptions about when Seffen's paper will appear in J. Engg. Mechanics:
Feb 2008.
F(Z,S) = k*Z*S
To correct misconceptions about when Seffen's paper will appear in J. Engg. Mechanics:
Feb 2008.
QUOTE (NEU-FONZE+Nov 24 2007, 01:48 PM)
Arthur:
My rubble pile smoldering model IS like a cigarette! I have a smoldering front in the rubble pile burning DOWN at a rate of 10^-3 cm per second. So in one day it burns down a distance of 60 x 60 x 24 x 10^-3 cm = 0.864 meters. On day 2 it burns down another 0.864 meters and so on. Hence, after 29 days it has burned a distance of 29 x 0.864 meters or 25 meters.
Yes, but if you slice that rubble pile into Twenty Nine 0.086 meter slices, each slice (going down) is LARGER than the one before it.
So if its consuming ALL of the material, in each .86 meter increment, the VOLUME of material burned each day is going up.
If it DOESN'T consume ALL the material in each .86 meter increment, then your 29 day estimate falls apart.
Take your pick.
Arthur
My rubble pile smoldering model IS like a cigarette! I have a smoldering front in the rubble pile burning DOWN at a rate of 10^-3 cm per second. So in one day it burns down a distance of 60 x 60 x 24 x 10^-3 cm = 0.864 meters. On day 2 it burns down another 0.864 meters and so on. Hence, after 29 days it has burned a distance of 29 x 0.864 meters or 25 meters.
Yes, but if you slice that rubble pile into Twenty Nine 0.086 meter slices, each slice (going down) is LARGER than the one before it.
So if its consuming ALL of the material, in each .86 meter increment, the VOLUME of material burned each day is going up.
If it DOESN'T consume ALL the material in each .86 meter increment, then your 29 day estimate falls apart.
Take your pick.
Arthur
QUOTE (Chainsaw,+Nov 24 2007, 02:17 PM)
Do not worry about the fires, the fires were multi front fires each tower can in fact be seen as a separate fire, Adding them together only increases the fuel available for the total pile and we also do not know the exact fuel consumed in the fire in the pile or before the buildings fell all we have is an estimate.
I'm not worried, I'm just pointing out the erroneous assumptions that indicated that a smoldering fire would have consumed all the available material in the pit in just 29 days.
Arthur
I'm not worried, I'm just pointing out the erroneous assumptions that indicated that a smoldering fire would have consumed all the available material in the pit in just 29 days.
Arthur
Assume constant local propagation rate. Spherical propagation in a volume consumes proportional to r^2, the total consumed proportional to r^3. Circular propagation on a surface consumes proportional to r, the total consumed being proportional to r^2.
No exponentials involved.
No exponentials involved.
Guys -
I'm the one who asked for someone less lazy than myself to do an *ESTIMATE* of the fuel consumption rate/insulation/temperature estimates in the rubble pile, and I want to thank NeuF for taking the first cut at the estimate I was too lazy to attempt.
Thank you, NeuF! You put us in the ballpark, which is as much as anyone could reasonably expect on a holiday, no less.
We all understand that the rubble pile was no closer to a hemisphere than a chicken is spherical, but the numbers at least gave us a point of departure for further, more sophisticated analyses (for which I am also grateful).
Estimates of fires are, as I pointed out when I first started posting on this topic many moons ago, are fundamentally suspect, as I've seen lots of fires (as we all have) and none of them could be described as "boxy-looking", yet all analyses assume cubical fires. Going from steady-state assumptions to chaotic dynamics usually includes lots of grains of salt and recognition that the linear (boxy) analyses provide data that's useful, and always wrong to some degree or another. The boxy-fire analyses' predictions are generally the numbers that the real fires avoid, much like teenagers' compliance with parental restrictions on what's acceptable behavior on dates.
The "boxy-fire" analyses gives me numbers that I generally multiply by three or so when estimating how hot the fires actually got, and I'm never surprised when that estimate is proved too low.
I'm generally more interested in phenomenology than curve-fitting, and I think we're already approaching a more realistic view of the fire in the rubble-pile than what we had before. I figure there were some unintended/happenstance foundries occurring in the million tons of rubble and burning fuel, plus a lot of nasty chemistry (esp., generation of chlorine from burning PVC and water vapor from burning hydrocarbons which formed HCl that ate the floor pans) plus sufficient hot-spot activity to melt whatever metals happened to be handy - lead from batteries, aluminum from everything, copper from wiring, and maybe even steel under rare (but not impossible) circumstances in the rubble pile.
It should also be noted that the fastest way to melt steel is to have electrical power lines short-out to the structure during a fire, and rubber insulation melts/burns at pretty low temperatures. There were lots of opportunities for that to happen, and coincidentally, the evidence for "crowbar shorts" to happen in a building would be the sounds of the circuit-breakers tripping. They sound like grenades going off. (So there's a source of BANGS in the WTC towers prior to the collapse, and there's a source for steel spheres and molten metal.)
Let's all remember the holiday spirit, here, and appreciate the honest efforts of our contributors.
Thanks again to all who've contributed to answering my question!
I'm the one who asked for someone less lazy than myself to do an *ESTIMATE* of the fuel consumption rate/insulation/temperature estimates in the rubble pile, and I want to thank NeuF for taking the first cut at the estimate I was too lazy to attempt.
Thank you, NeuF! You put us in the ballpark, which is as much as anyone could reasonably expect on a holiday, no less.
We all understand that the rubble pile was no closer to a hemisphere than a chicken is spherical, but the numbers at least gave us a point of departure for further, more sophisticated analyses (for which I am also grateful).
Estimates of fires are, as I pointed out when I first started posting on this topic many moons ago, are fundamentally suspect, as I've seen lots of fires (as we all have) and none of them could be described as "boxy-looking", yet all analyses assume cubical fires. Going from steady-state assumptions to chaotic dynamics usually includes lots of grains of salt and recognition that the linear (boxy) analyses provide data that's useful, and always wrong to some degree or another. The boxy-fire analyses' predictions are generally the numbers that the real fires avoid, much like teenagers' compliance with parental restrictions on what's acceptable behavior on dates.
The "boxy-fire" analyses gives me numbers that I generally multiply by three or so when estimating how hot the fires actually got, and I'm never surprised when that estimate is proved too low.
I'm generally more interested in phenomenology than curve-fitting, and I think we're already approaching a more realistic view of the fire in the rubble-pile than what we had before. I figure there were some unintended/happenstance foundries occurring in the million tons of rubble and burning fuel, plus a lot of nasty chemistry (esp., generation of chlorine from burning PVC and water vapor from burning hydrocarbons which formed HCl that ate the floor pans) plus sufficient hot-spot activity to melt whatever metals happened to be handy - lead from batteries, aluminum from everything, copper from wiring, and maybe even steel under rare (but not impossible) circumstances in the rubble pile.
It should also be noted that the fastest way to melt steel is to have electrical power lines short-out to the structure during a fire, and rubber insulation melts/burns at pretty low temperatures. There were lots of opportunities for that to happen, and coincidentally, the evidence for "crowbar shorts" to happen in a building would be the sounds of the circuit-breakers tripping. They sound like grenades going off. (So there's a source of BANGS in the WTC towers prior to the collapse, and there's a source for steel spheres and molten metal.)
Let's all remember the holiday spirit, here, and appreciate the honest efforts of our contributors.
Thanks again to all who've contributed to answering my question!
QUOTE (David B. Benson+Nov 24 2007, 02:44 PM)
Assume constant local propagation rate. Spherical propagation in a volume consumes proportional to r^2, the total consumed proportional to r^3. Circular propagation on a surface consumes proportional to r, the total consumed being proportional to r^2.
No exponentials involved.
True, I was using the term Exponential incorrectly.
The fact is though, the table of material consumed I posted is accurate and does increase each day and thus is NOT an indication of what happened in the pit, which is the REAL issue.
Arthur
No exponentials involved.
True, I was using the term Exponential incorrectly.
The fact is though, the table of material consumed I posted is accurate and does increase each day and thus is NOT an indication of what happened in the pit, which is the REAL issue.
Arthur
QUOTE (shagster+Nov 23 2007, 05:26 AM)
The crush-up model for WTC7 predicts a collapse duration of about 6.6 s if the E1/mh is considered constant and similar to the value of that for the upper regions of the WTC towers, if I did the math correctly.
The crush-up diffeq for a constant E1/mh simplifies to
t = sqrt(2H/[g-E1/(mh)])
where H is the building height, m is the mass above the collapse front, and h is the inter-story height.
For an E1/mh of 1.57 m/s^2, the collapse duration for WTC7 is about 6.6 seconds, which is close to the observed collapse duration of the final global crush-up of WTC7.
t = sqrt(2H/[g-E1/(mh)])
t= sqrt(2*178/[9.81-1.57])
t = 6.57 s
Doubling E1/mh doesn't have a large effect on the duration for WTC7 when E1/mh is small relative to g. The square root function in the crush-up equation also makes the duration insensitive to E1/mh.
Increasing E1/mh to 3 m/s^2 gives a WTC7 collapse duration of 7.2 s.
Reducing E1/mh to 0.8 m/s^2 gives a WTC7 collapse duration of 6.3 s.
When E1 is zero, the crush-up equation reduces to the familiar
t = sqrt(2H/g)
Shagster, how did you derive that equation, this is only valid for constant acceleration, but at the end if E1 is constant then the ratio E1/m(y) becomes infinite. The exact limit can be determined with the Bazant crush-up equation, I ran a simple vbscript and concluded that the E1/mass ratio was about 4 times more than the ones of wtc1,2, I could be completely wrong but it should be more because the building was massively strong, designed to survive earthquakes.
The crush-up diffeq for a constant E1/mh simplifies to
t = sqrt(2H/[g-E1/(mh)])
where H is the building height, m is the mass above the collapse front, and h is the inter-story height.
For an E1/mh of 1.57 m/s^2, the collapse duration for WTC7 is about 6.6 seconds, which is close to the observed collapse duration of the final global crush-up of WTC7.
t = sqrt(2H/[g-E1/(mh)])
t= sqrt(2*178/[9.81-1.57])
t = 6.57 s
Doubling E1/mh doesn't have a large effect on the duration for WTC7 when E1/mh is small relative to g. The square root function in the crush-up equation also makes the duration insensitive to E1/mh.
Increasing E1/mh to 3 m/s^2 gives a WTC7 collapse duration of 7.2 s.
Reducing E1/mh to 0.8 m/s^2 gives a WTC7 collapse duration of 6.3 s.
When E1 is zero, the crush-up equation reduces to the familiar
t = sqrt(2H/g)
Shagster, how did you derive that equation, this is only valid for constant acceleration, but at the end if E1 is constant then the ratio E1/m(y) becomes infinite. The exact limit can be determined with the Bazant crush-up equation, I ran a simple vbscript and concluded that the E1/mass ratio was about 4 times more than the ones of wtc1,2, I could be completely wrong but it should be more because the building was massively strong, designed to survive earthquakes.
QUOTE (David B. Benson+Nov 23 2007, 11:04 PM)
Oh yes. In determining the stretch, it is not assumed that all the materials remain in the crushed block. For example, both the office materials and the concrete, once sufficiently fine particles, could be blown out of the tower in the wind of the departing air.
It doesn't sound realistic to me. The particles are only fine if they are crushed completely, but at that time the air is already gone.
It doesn't sound realistic to me. The particles are only fine if they are crushed completely, but at that time the air is already gone.
QUOTE (einsteen+Nov 24 2007, 02:54 PM)
The particles are only fine if they are crushed completely, but at that time the air is already gone.
Only in a 'perfect' world.
(1) The trusses above are not completely crushed when the concrete is. Some some small volume of air is still to be expelled.
(2) Surely some of the escaping air goes up and out.
Only in a 'perfect' world.
(1) The trusses above are not completely crushed when the concrete is. Some some small volume of air is still to be expelled.
(2) Surely some of the escaping air goes up and out.
einsteen
Incorrect, only the particles which have been crushed fine are carried away with the air(a small percentage), the remainder(most of it) is left behind. The commutation that occurred during the collapse produced all sizes, they were separated by the moving air.
Grumpy
QUOTE
The particles are only fine if they are crushed completely, but at that time the air is already gone.
Incorrect, only the particles which have been crushed fine are carried away with the air(a small percentage), the remainder(most of it) is left behind. The commutation that occurred during the collapse produced all sizes, they were separated by the moving air.
Grumpy
But how much will that be ? You can neglect that amount. I'm back in a few minutes with some screendumps.
I decided to make an animated gif, David can't watch videos
http://i16.tinypic.com/8egoq3l.gif
- These are no fine particles, because they follow a parabolic track. We see a couple of independent parts each following their track.
- The centre of mass is still at around the middle of wtc2, as expected when mass is ejected in all directories.
- How can fine particles damage wtc7 ?
http://i16.tinypic.com/8egoq3l.gif
- These are no fine particles, because they follow a parabolic track. We see a couple of independent parts each following their track.
- The centre of mass is still at around the middle of wtc2, as expected when mass is ejected in all directories.
- How can fine particles damage wtc7 ?
QUOTE (einsteen+Nov 24 2007, 11:19 PM)
I decided to make an animated gif, David can't watch videos
http://i16.tinypic.com/8egoq3l.gif
- These are no fine particles, because they follow a parabolic track. We see a couple of independent parts each following their track.
- The centre of mass is still at around the middle of wtc2, as expected when mass is ejected in all directories.
- How can fine particles damage wtc7 ?
einsteen
Look
at the fluid flow effects the leading edge has parts of steel Columns and beams those would hit WTC 6 and be deflected into WTC 7s lower cantilevered beam structure.
IT is important to note that the lower beam structure failure would lead to a collapse progressive from one side to the other, it is hard to tell from that gif though if that is what I am seeing, However it looks like it.
http://i16.tinypic.com/8egoq3l.gif
- These are no fine particles, because they follow a parabolic track. We see a couple of independent parts each following their track.
- The centre of mass is still at around the middle of wtc2, as expected when mass is ejected in all directories.
- How can fine particles damage wtc7 ?
einsteen
Look
at the fluid flow effects the leading edge has parts of steel Columns and beams those would hit WTC 6 and be deflected into WTC 7s lower cantilevered beam structure.
IT is important to note that the lower beam structure failure would lead to a collapse progressive from one side to the other, it is hard to tell from that gif though if that is what I am seeing, However it looks like it.
QUOTE (einsteen+Nov 24 2007, 04:19 PM)
- These are no fine particles, because ,,,
- How can fine particles damage wtc7 ?
At that resolution you simply cannot see such.
Can't, unless massive quantities. Large sections of the north wall of WTC 1 did.
=======
Anyway, my comments were directed towards determining the stretch.
Thanks for maiking the .gif file. It was interesting to watch.
- How can fine particles damage wtc7 ?
At that resolution you simply cannot see such.
Can't, unless massive quantities. Large sections of the north wall of WTC 1 did.
=======
Anyway, my comments were directed towards determining the stretch.
Thanks for maiking the .gif file. It was interesting to watch.
QUOTE (David B. Benson+Nov 24 2007, 11:41 PM)
At that resolution you simply cannot see such.
Can't, unless massive quantities. Large sections of the north wall of WTC 1 did.
=======
Anyway, mu comments were directed towards determining the stretch.
Thanks for maiking the .gif file. It was interesting to watch.
DBB, I was referring to the fluid dynamic effects caused by the aerodynamic effect created by large pieces falling rapidly though air crating a vacuum of low pressure area behind the object.
Even in the gif I thought that I saw some of those, they can indicate where large pieces in the debris cloud are, however it would take a better resolution than in the e gif, as you stated.
I will have to look at the video some more. I had not noticed those before.
Can't, unless massive quantities. Large sections of the north wall of WTC 1 did.
=======
Anyway, mu comments were directed towards determining the stretch.
Thanks for maiking the .gif file. It was interesting to watch.
DBB, I was referring to the fluid dynamic effects caused by the aerodynamic effect created by large pieces falling rapidly though air crating a vacuum of low pressure area behind the object.
Even in the gif I thought that I saw some of those, they can indicate where large pieces in the debris cloud are, however it would take a better resolution than in the e gif, as you stated.
I will have to look at the video some more. I had not noticed those before.
QUOTE (Chainsaw,+Nov 24 2007, 04:54 PM)
DBB, I was referring to the fluid dynamic effects caused by the aerodynamic effect created by large pieces falling rapidly though air crating a vacuum of low pressure area behind the object.
Most of the crushed materials were in pieces too large to fit through the windows. (Otherwise, one would see much more of it.) Every time a sizable section of exterior wall separated, this left a big hole through which the crushed materials could escape.
In a still posted by metamars this effect was more obvious than this one.
Given the amount of window area in the exterior walls sections, it is most unclear how much of this aerodynamic effect would have occurred. But it is certainly of interest.
Most of the crushed materials were in pieces too large to fit through the windows. (Otherwise, one would see much more of it.) Every time a sizable section of exterior wall separated, this left a big hole through which the crushed materials could escape.
In a still posted by metamars this effect was more obvious than this one.
Given the amount of window area in the exterior walls sections, it is most unclear how much of this aerodynamic effect would have occurred. But it is certainly of interest.
Here is a run with a standard deviation of only 0.195 meters, only three-quarters of a pixel. The columns are: time in seconds, measured drop in meters, calculated drop in meters, crushing front depth below original position of a (nominal) top in meters, speed in m/s. (The crushing front depth is useful only for comparisons. About 17 stories were crushed in the 3.82 seconds.)
0.00 0.190 0.001 79.926 0.446
0.06 0.260 0.024 79.972 1.055
0.09 0.246 0.037 79.998 1.271
0.25 0.444 0.202 80.329 2.847
0.28 0.449 0.260 80.445 3.222
0.29 0.520 0.268 80.460 3.269
0.41 0.759 0.496 80.910 4.418
0.45 0.857 0.610 81.134 4.888
0.50 0.898 0.740 81.388 5.375
0.52 1.062 0.792 81.489 5.555
0.65 1.396 1.188 82.252 6.769
0.68 1.415 1.317 82.498 7.116
0.70 1.626 1.390 82.636 7.305
0.79 1.972 1.737 83.290 8.135
0.84 2.126 1.974 83.730 8.649
0.88 2.211 2.159 84.072 9.029
0.89 2.471 2.218 84.181 9.146
1.00 3.013 2.799 85.233 10.212
1.04 3.173 3.036 85.656 10.611
1.04 3.090 3.072 85.719 10.669
1.09 3.576 3.352 86.214 11.114
1.21 4.284 4.171 87.631 12.301
1.21 4.266 4.198 87.677 12.338
1.24 4.573 4.387 87.998 12.590
1.34 5.332 5.174 89.311 13.575
1.36 5.384 5.359 89.615 13.793
1.41 5.807 5.726 90.213 14.211
1.44 6.286 6.059 90.749 14.576
1.53 6.900 6.843 91.989 15.384
1.56 7.413 7.185 92.522 15.706
1.59 7.615 7.528 93.054 16.012
1.63 8.150 7.909 93.639 16.334
1.69 8.628 8.614 94.714 16.884
1.74 9.342 9.124 95.482 17.250
1.78 9.741 9.659 96.280 17.609
1.82 10.339 10.034 96.835 17.847
1.82 10.048 10.134 96.983 17.909
1.90 11.249 11.010 98.268 18.420
1.95 11.708 11.650 99.195 18.763
1.95 11.738 11.764 99.359 18.822
1.99 12.485 12.265 100.079 19.072
2.07 13.292 13.298 101.549 19.551
2.07 13.504 13.300 101.551 19.552
2.13 14.349 14.162 102.762 19.918
2.14 14.374 14.314 102.974 19.979
2.20 15.281 15.129 104.108 20.297
2.20 15.248 15.158 104.148 20.308
2.25 16.170 15.955 105.247 20.597
2.29 16.672 16.590 106.114 20.815
2.30 16.531 16.611 106.143 20.823
2.31 17.124 16.887 106.519 20.914
2.36 17.925 17.609 107.497 21.144
2.41 18.682 18.353 108.499 21.370
2.43 18.763 18.660 108.909 21.459
2.45 19.133 19.048 109.426 21.570
2.48 19.810 19.572 110.123 21.715
2.52 20.377 20.146 110.883 21.868
2.55 20.938 20.697 111.609 22.010
2.61 22.130 21.765 113.007 22.271
2.62 22.116 21.905 113.189 22.304
2.64 22.485 22.249 113.636 22.384
2.70 23.539 23.181 114.841 22.593
2.75 24.513 24.213 116.167 22.812
2.77 24.840 24.465 116.489 22.863
2.80 25.416 25.082 117.276 22.986
2.85 26.401 25.961 118.390 23.156
2.85 26.370 26.028 118.475 23.168
2.92 27.700 27.331 120.115 23.405
2.93 27.817 27.414 120.218 23.419
2.96 28.404 28.061 121.028 23.531
2.98 28.813 28.426 121.483 23.592
3.06 30.191 29.867 123.268 23.825
3.07 30.538 30.023 123.461 23.849
3.07 30.429 30.126 123.588 23.865
3.15 32.223 31.684 125.499 24.098
3.17 32.467 32.142 126.057 24.164
3.22 33.285 33.020 127.125 24.286
3.25 34.331 33.724 127.976 24.381
3.29 34.885 34.481 128.888 24.481
3.35 36.216 35.692 130.342 24.634
3.36 36.013 35.990 130.697 24.671
3.37 36.491 36.149 130.887 24.690
3.46 38.368 37.980 133.061 24.905
3.48 38.776 38.330 133.475 24.945
3.49 38.805 38.571 133.760 24.972
3.55 40.231 39.847 135.260 25.112
3.61 41.580 41.120 136.748 25.245
3.63 41.661 41.704 137.428 25.305
3.65 42.338 42.121 137.912 25.346
3.68 43.228 42.770 138.665 25.410
3.73 44.068 43.929 140.002 25.521
3.74 44.522 43.961 140.040 25.524
3.76 44.453 44.421 140.569 25.568
3.82 45.953 45.785 142.133 25.692
CODE
0.00 0.190 0.001 79.926 0.446
0.06 0.260 0.024 79.972 1.055
0.09 0.246 0.037 79.998 1.271
0.25 0.444 0.202 80.329 2.847
0.28 0.449 0.260 80.445 3.222
0.29 0.520 0.268 80.460 3.269
0.41 0.759 0.496 80.910 4.418
0.45 0.857 0.610 81.134 4.888
0.50 0.898 0.740 81.388 5.375
0.52 1.062 0.792 81.489 5.555
0.65 1.396 1.188 82.252 6.769
0.68 1.415 1.317 82.498 7.116
0.70 1.626 1.390 82.636 7.305
0.79 1.972 1.737 83.290 8.135
0.84 2.126 1.974 83.730 8.649
0.88 2.211 2.159 84.072 9.029
0.89 2.471 2.218 84.181 9.146
1.00 3.013 2.799 85.233 10.212
1.04 3.173 3.036 85.656 10.611
1.04 3.090 3.072 85.719 10.669
1.09 3.576 3.352 86.214 11.114
1.21 4.284 4.171 87.631 12.301
1.21 4.266 4.198 87.677 12.338
1.24 4.573 4.387 87.998 12.590
1.34 5.332 5.174 89.311 13.575
1.36 5.384 5.359 89.615 13.793
1.41 5.807 5.726 90.213 14.211
1.44 6.286 6.059 90.749 14.576
1.53 6.900 6.843 91.989 15.384
1.56 7.413 7.185 92.522 15.706
1.59 7.615 7.528 93.054 16.012
1.63 8.150 7.909 93.639 16.334
1.69 8.628 8.614 94.714 16.884
1.74 9.342 9.124 95.482 17.250
1.78 9.741 9.659 96.280 17.609
1.82 10.339 10.034 96.835 17.847
1.82 10.048 10.134 96.983 17.909
1.90 11.249 11.010 98.268 18.420
1.95 11.708 11.650 99.195 18.763
1.95 11.738 11.764 99.359 18.822
1.99 12.485 12.265 100.079 19.072
2.07 13.292 13.298 101.549 19.551
2.07 13.504 13.300 101.551 19.552
2.13 14.349 14.162 102.762 19.918
2.14 14.374 14.314 102.974 19.979
2.20 15.281 15.129 104.108 20.297
2.20 15.248 15.158 104.148 20.308
2.25 16.170 15.955 105.247 20.597
2.29 16.672 16.590 106.114 20.815
2.30 16.531 16.611 106.143 20.823
2.31 17.124 16.887 106.519 20.914
2.36 17.925 17.609 107.497 21.144
2.41 18.682 18.353 108.499 21.370
2.43 18.763 18.660 108.909 21.459
2.45 19.133 19.048 109.426 21.570
2.48 19.810 19.572 110.123 21.715
2.52 20.377 20.146 110.883 21.868
2.55 20.938 20.697 111.609 22.010
2.61 22.130 21.765 113.007 22.271
2.62 22.116 21.905 113.189 22.304
2.64 22.485 22.249 113.636 22.384
2.70 23.539 23.181 114.841 22.593
2.75 24.513 24.213 116.167 22.812
2.77 24.840 24.465 116.489 22.863
2.80 25.416 25.082 117.276 22.986
2.85 26.401 25.961 118.390 23.156
2.85 26.370 26.028 118.475 23.168
2.92 27.700 27.331 120.115 23.405
2.93 27.817 27.414 120.218 23.419
2.96 28.404 28.061 121.028 23.531
2.98 28.813 28.426 121.483 23.592
3.06 30.191 29.867 123.268 23.825
3.07 30.538 30.023 123.461 23.849
3.07 30.429 30.126 123.588 23.865
3.15 32.223 31.684 125.499 24.098
3.17 32.467 32.142 126.057 24.164
3.22 33.285 33.020 127.125 24.286
3.25 34.331 33.724 127.976 24.381
3.29 34.885 34.481 128.888 24.481
3.35 36.216 35.692 130.342 24.634
3.36 36.013 35.990 130.697 24.671
3.37 36.491 36.149 130.887 24.690
3.46 38.368 37.980 133.061 24.905
3.48 38.776 38.330 133.475 24.945
3.49 38.805 38.571 133.760 24.972
3.55 40.231 39.847 135.260 25.112
3.61 41.580 41.120 136.748 25.245
3.63 41.661 41.704 137.428 25.305
3.65 42.338 42.121 137.912 25.346
3.68 43.228 42.770 138.665 25.410
3.73 44.068 43.929 140.002 25.521
3.74 44.522 43.961 140.040 25.524
3.76 44.453 44.421 140.569 25.568
3.82 45.953 45.785 142.133 25.692
Rather dull reading, but perhaps somebody will care to graph the measured and calculated drops versus time.
Editied to add: the clculated drops appear to have a systematic bias of -0.19 meters.
I'll check further and fix it tomorrow.
QUOTE (quicknthedead+Nov 24 2007, 04:59 PM)
Unfortunately this is just a pile of Bovine Poo that you made up.
There is no evidence that what you claim happened.
Just because it doesn't make sense to you to let the building burn, doesn't mean they didn't.
I have to say, I would find it FAR more incredulous that a demolition company would enter a BURNING building (that would have been burning for HOURS) that had unknown STRUCTURAL damage with a load of HE and det cord and then try to set demolition charges.
Even further, having DONE so, there is no reason that the demolition company personal who risked their lives for the NYFD would then keep their HEROICS SECRET.
We've been through this with you before, do you have ANYTHING NEW?
Arthur
Yes. This does not tally with the time available to prepare WTC7 for CD; and yes, the fact it was on fire compounds atmosphere's assertion to the point of being unbelievable.
Going to the website he gives underscores this. Of the examples of CDI's quick-response times, the best found is the first example, and it is not even close to the situation found at WTC7:
Sheikh A. Alakl Residential and Commercial Center.......
Half of the 17-story Sheikh A. Alakl Apartment Building in Jeddah, Saudi Arabia collapsed when portions of the new reinforced concrete facility were overloaded during final stages of construction. At the request of Bechtel, Controlled Demolition Incorporated’s team mobilized to the site in less than 24 hours, prepared the central-core, flat slab, reinforced concrete structure in another 27 hours and put the balance of the building on the ground with absolute safety just 96 hours after the start of demolition preparations.
In addition, CD expert Danny Jowenko's reactions was one of astonishment when in his interview he learned WTC7 had been on fire that day. He knew it was a CD, and the fire made him all the more certain it had to have been prepped before 9/11.
A demolition team could easily entered the building on the first couple of floors and the basement , there were no fires there !!! Also the fires just started that morning.
For fire fighters it was much more risky to do their job because the fires where localized around the areas where debris entered. They could be hit by falling debris or even face floors collapsing .
Heat and smoke go up ,which means that the basement and the first floors could be entered without any problems. They didn't tell Jowenko this in the interview.
Until this day he's even more convinced of a the controlled demolition of WTC 7 , after talking to other specialist and looking into all available information. Jowenko's work on video is even presented on the implosion world website , so I assume he knows some people over there. He says "American demolition company's can not speak the truth . When they do their history . Also the US government is an important costumer for those company's ,as can be concluded from the "controlled demolition " website . By the Way Jowenko is not the only European explosives expert having problems with the official story about WTC 7 . They do agree with the NIST report about the collapses of the towers. You can't blame them for being conspiracy theorist.
An American demolition team managed to get a job in Saudi Arabia done in a very short time. Most of the time was wasted in bringing their men and equipment on the scene. At 9/11 demolition teams rushed to the scene as soon as the first plane crashed into one of the towers. I believe they had the possibility to bring down WTC 7 in a couple of hours . You cant compare controlled demolitions under normal conditions with the situation at 9/11 .
Jowenko describes how it can be done in very short time . He still sticks to his comment's ( can be watched on You-tube) to this day , and still wants to answer questions about it. Just give him a call !
There is no evidence that what you claim happened.
Just because it doesn't make sense to you to let the building burn, doesn't mean they didn't.
I have to say, I would find it FAR more incredulous that a demolition company would enter a BURNING building (that would have been burning for HOURS) that had unknown STRUCTURAL damage with a load of HE and det cord and then try to set demolition charges.
Even further, having DONE so, there is no reason that the demolition company personal who risked their lives for the NYFD would then keep their HEROICS SECRET.
We've been through this with you before, do you have ANYTHING NEW?
Arthur
Yes. This does not tally with the time available to prepare WTC7 for CD; and yes, the fact it was on fire compounds atmosphere's assertion to the point of being unbelievable.
Going to the website he gives underscores this. Of the examples of CDI's quick-response times, the best found is the first example, and it is not even close to the situation found at WTC7:
Sheikh A. Alakl Residential and Commercial Center.......
Half of the 17-story Sheikh A. Alakl Apartment Building in Jeddah, Saudi Arabia collapsed when portions of the new reinforced concrete facility were overloaded during final stages of construction. At the request of Bechtel, Controlled Demolition Incorporated’s team mobilized to the site in less than 24 hours, prepared the central-core, flat slab, reinforced concrete structure in another 27 hours and put the balance of the building on the ground with absolute safety just 96 hours after the start of demolition preparations.
In addition, CD expert Danny Jowenko's reactions was one of astonishment when in his interview he learned WTC7 had been on fire that day. He knew it was a CD, and the fire made him all the more certain it had to have been prepped before 9/11.
A demolition team could easily entered the building on the first couple of floors and the basement , there were no fires there !!! Also the fires just started that morning.
For fire fighters it was much more risky to do their job because the fires where localized around the areas where debris entered. They could be hit by falling debris or even face floors collapsing .
Heat and smoke go up ,which means that the basement and the first floors could be entered without any problems. They didn't tell Jowenko this in the interview.
Until this day he's even more convinced of a the controlled demolition of WTC 7 , after talking to other specialist and looking into all available information. Jowenko's work on video is even presented on the implosion world website , so I assume he knows some people over there. He says "American demolition company's can not speak the truth . When they do their history . Also the US government is an important costumer for those company's ,as can be concluded from the "controlled demolition " website . By the Way Jowenko is not the only European explosives expert having problems with the official story about WTC 7 . They do agree with the NIST report about the collapses of the towers. You can't blame them for being conspiracy theorist.
An American demolition team managed to get a job in Saudi Arabia done in a very short time. Most of the time was wasted in bringing their men and equipment on the scene. At 9/11 demolition teams rushed to the scene as soon as the first plane crashed into one of the towers. I believe they had the possibility to bring down WTC 7 in a couple of hours . You cant compare controlled demolitions under normal conditions with the situation at 9/11 .
Jowenko describes how it can be done in very short time . He still sticks to his comment's ( can be watched on You-tube) to this day , and still wants to answer questions about it. Just give him a call !
QUOTE (atmosphere+Nov 25 2007, 04:48 PM)
A demolition team could easily entered the building on the first couple of floors and the basement , there were no fires there !!! Also the fires just started that morning.
For fire fighters it was much more risky to do their job because the fires where localized around the areas where debris entered. They could be hit by falling debris or even face floors collapsing .
Heat and smoke go up ,which means that the basement and the first floors could be entered without any problems. They didn't tell Jowenko this in the interview.
Until this day he's even more convinced of a the controlled demolition of WTC 7 , after talking to other specialist and looking into all available information. Jowenko's work on video is even presented on the implosion world website , so I assume he knows some people over there. He says "American demolition company's can not speak the truth . When they do their history . Also the US government is an important costumer for those company's ,as can be concluded from the "controlled demolition " website . By the Way Jowenko is not the only European explosives expert having problems with the official story about WTC 7 . They do agree with the NIST report about the collapses of the towers. You can't blame them for being conspiracy theorist.
An American demolition team managed to get a job in Saudi Arabia done in a very short time. Most of the time was wasted in bringing their men and equipment on the scene. At 9/11 demolition teams rushed to the scene as soon as the first plane crashed into one of the towers. I believe they had the possibility to bring down WTC 7 in a couple of hours . You cant compare controlled demolitions under normal conditions with the situation at 9/11 .
Jowenko describes how it can be done in very short time . He still sticks to his comment's ( can be watched on You-tube) to this day , and still wants to answer questions about it. Just give him a call !
Do you have his number, I would like to discuss perimeters with him.
QUOTE (atmosphere+Nov 25 2007, 11:48 AM)
A demolition team could easily entered the building on the first couple of floors and the basement , there were no fires there !!! Also the fires just started that morning.
For fire fighters it was much more risky to do their job because the fires where localized around the areas where debris entered. They could be hit by falling debris or even face floors collapsing .
Heat and smoke go up ,which means that the basement and the first floors could be entered without any problems. They didn't tell Jowenko this in the interview.
Until this day he's even more convinced of a the controlled demolition of WTC 7 , after talking to other specialist and looking into all available information. Jowenko's work on video is even presented on the implosion world website , so I assume he knows some people over there. He says "American demolition company's can not speak the truth . When they do their history . Also the US government is an important costumer for those company's ,as can be concluded from the "controlled demolition " website . By the Way Jowenko is not the only European explosives expert having problems with the official story about WTC 7 . They do agree with the NIST report about the collapses of the towers. You can't blame them for being conspiracy theorist.
An American demolition team managed to get a job in Saudi Arabia done in a very short time. Most of the time was wasted in bringing their men and equipment on the scene. At 9/11 demolition teams rushed to the scene as soon as the first plane crashed into one of the towers. I believe they had the possibility to bring down WTC 7 in a couple of hours . You cant compare controlled demolitions under normal conditions with the situation at 9/11 .
Jowenko describes how it can be done in very short time . He still sticks to his comment's ( can be watched on You-tube) to this day , and still wants to answer questions about it. Just give him a call !
Again, nothing but SUPPOSITION.
NO FACTS.
NOTHING at all that supports your wild claims.
Jowenko is obviously not too bright if he claims he can tell its a CD from the videos.
More so if he thinks that CD companies do much work for the FEDERAL govt.
The VAST majority of their work is done for PRIVATE companies and only require LOCAL approval (in fact I've never seen a implosion done by a CD company of a FEDERAL building).
Getting BATF approval for use of explosives simply means showing you have the need, training and approved storage and transportation facilities.
Arthur
For fire fighters it was much more risky to do their job because the fires where localized around the areas where debris entered. They could be hit by falling debris or even face floors collapsing .
Heat and smoke go up ,which means that the basement and the first floors could be entered without any problems. They didn't tell Jowenko this in the interview.
Until this day he's even more convinced of a the controlled demolition of WTC 7 , after talking to other specialist and looking into all available information. Jowenko's work on video is even presented on the implosion world website , so I assume he knows some people over there. He says "American demolition company's can not speak the truth . When they do their history . Also the US government is an important costumer for those company's ,as can be concluded from the "controlled demolition " website . By the Way Jowenko is not the only European explosives expert having problems with the official story about WTC 7 . They do agree with the NIST report about the collapses of the towers. You can't blame them for being conspiracy theorist.
An American demolition team managed to get a job in Saudi Arabia done in a very short time. Most of the time was wasted in bringing their men and equipment on the scene. At 9/11 demolition teams rushed to the scene as soon as the first plane crashed into one of the towers. I believe they had the possibility to bring down WTC 7 in a couple of hours . You cant compare controlled demolitions under normal conditions with the situation at 9/11 .
Jowenko describes how it can be done in very short time . He still sticks to his comment's ( can be watched on You-tube) to this day , and still wants to answer questions about it. Just give him a call !
Again, nothing but SUPPOSITION.
NO FACTS.
NOTHING at all that supports your wild claims.
Jowenko is obviously not too bright if he claims he can tell its a CD from the videos.
More so if he thinks that CD companies do much work for the FEDERAL govt.
The VAST majority of their work is done for PRIVATE companies and only require LOCAL approval (in fact I've never seen a implosion done by a CD company of a FEDERAL building).
Getting BATF approval for use of explosives simply means showing you have the need, training and approved storage and transportation facilities.
Arthur
QUOTE (Chainsaw,+Nov 25 2007, 05:05 PM)
Do you have his number, I would like to discuss perimeters with him.
Jowenko Explosieve Demolitie BV
Veersewg 107
4351SL Veere
tel.(0118)612735
fax.(0118)612779
He lives just 3 miles away from me , so it wasn't very hard to find his number.
Jowenko Explosieve Demolitie BV
Veersewg 107
4351SL Veere
tel.(0118)612735
fax.(0118)612779
He lives just 3 miles away from me , so it wasn't very hard to find his number.
QUOTE (adoucette+Nov 25 2007, 11:19 AM)
Again, nothing but SUPPOSITION.
Jowenko is obviously not too bright if he claims he can tell its a CD from the videos.
Look who's talking.
He is an expert with authority in his field (you are not), and can tell it is one from the videos (along with millions of others who have seen the collapse), reason enough to get a new 9/11 crime investigation going (there has never been one yet).
{The 9/11 Commission Report is a rag comparable to the Warren Commission Report}
Jowenko is obviously not too bright if he claims he can tell its a CD from the videos.
Look who's talking.
He is an expert with authority in his field (you are not), and can tell it is one from the videos (along with millions of others who have seen the collapse), reason enough to get a new 9/11 crime investigation going (there has never been one yet).
{The 9/11 Commission Report is a rag comparable to the Warren Commission Report}
QUOTE (adoucette+Nov 25 2007, 06:19 PM)
Again, nothing but SUPPOSITION.
NO FACTS.
NOTHING at all that supports your wild claims.
Jowenko is obviously not too bright if he claims he can tell its a CD from the videos.
More so if he thinks that CD companies do much work for the FEDERAL govt.
The VAST majority of their work is done for PRIVATE companies and only require LOCAL approval (in fact I've never seen a implosion done by a CD company of a FEDERAL building).
Getting BATF approval for use of explosives simply means showing you have the need, training and approved storage and transportation facilities.
Arthur
-Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree?
-Fact is WTC 7 had relatively few columns
-fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
- Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are my claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
NO FACTS.
NOTHING at all that supports your wild claims.
Jowenko is obviously not too bright if he claims he can tell its a CD from the videos.
More so if he thinks that CD companies do much work for the FEDERAL govt.
The VAST majority of their work is done for PRIVATE companies and only require LOCAL approval (in fact I've never seen a implosion done by a CD company of a FEDERAL building).
Getting BATF approval for use of explosives simply means showing you have the need, training and approved storage and transportation facilities.
Arthur
-Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree?
-Fact is WTC 7 had relatively few columns
-fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
- Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are my claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
QUOTE (quicknthedead+Nov 25 2007, 02:35 PM)
He is an expert with authority in his field (you are not), and can tell it is one from the videos
Really?
I must have missed his SCIENTIFIC EXPLANTION as to why he can tell for CERTAIN that its a CD.
Arthur
Really?
I must have missed his SCIENTIFIC EXPLANTION as to why he can tell for CERTAIN that its a CD.
Arthur
there are lots of way's a demolition company can be involved with the government . Just a few examples :
Demolition Inc., was subcontracted by Tully Construction to coordinate the removal of rubble from Ground Zero and the disposal of the structural steel in the months following the attack.
QUOTE
Department of Justice
Professionalism, integrity and security are critical to Department of Justice investigations. Controlled Demolition Incorporated (CDI) has the appropriate clearances and internal controls to support federal agencies involved in domestic or foreign investigations which involve the gathering of criminal evidence critical to our precepts of due process. The Loizeaux Group’s controlled, professional services and unmatched communication skills can support critical operations under tenuous circumstances.
Department of State
US Foreign Policy initiatives are generally the first forum in which the American tax dollar influences relations with other countries. Time is frequently of the essence in the negotiation and implementation of agreements between countries. Controlled Demolition Incorporated (CDI) has, on several occasions, provided negotiation backup and field performance support for US Department of State contracts which are critical to US Government interests. From the design of and modification to missile fabrication facilities in South Africa to the elimination of weapons of mass destruction in Central European countries, Controlled Demolition Incorporated has the technical expertise and international network to assist in budgeting and, subsequently, implementing agreements which make the world a safer place.
Professionalism, integrity and security are critical to Department of Justice investigations. Controlled Demolition Incorporated (CDI) has the appropriate clearances and internal controls to support federal agencies involved in domestic or foreign investigations which involve the gathering of criminal evidence critical to our precepts of due process. The Loizeaux Group’s controlled, professional services and unmatched communication skills can support critical operations under tenuous circumstances.
Department of State
US Foreign Policy initiatives are generally the first forum in which the American tax dollar influences relations with other countries. Time is frequently of the essence in the negotiation and implementation of agreements between countries. Controlled Demolition Incorporated (CDI) has, on several occasions, provided negotiation backup and field performance support for US Department of State contracts which are critical to US Government interests. From the design of and modification to missile fabrication facilities in South Africa to the elimination of weapons of mass destruction in Central European countries, Controlled Demolition Incorporated has the technical expertise and international network to assist in budgeting and, subsequently, implementing agreements which make the world a safer place.
Demolition Inc., was subcontracted by Tully Construction to coordinate the removal of rubble from Ground Zero and the disposal of the structural steel in the months following the attack.
QUOTE (atmosphere+Nov 25 2007, 02:41 PM)
-Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree?
Yes, but then one has to have people WILLING to go into a DAMAGED/BURNING building and PLACE the explosives and wire them so they go off at the exact same time. NO ONE saw this happen and NONE of the people who supposedly did this HEROIC act have mentioned it (for NO apparent reason)
Finally, setting the explosives on one floor to cause the building to collapse would make ONE HECK OF A BIG BANG when they went off, something that is MISSING from the videos of the collapse and from the eyewitness testimony of the people who were there at the collapse.
QUOTE (atmosphere+Nov 25 2007, 02:41 PM)
-Fact is WTC 7 had relatively few columns
Not really, it had a floor area of almost an ACRE.
If it was a CD it would have been the LARGEST CD in history.
Which you claim was done in the SHORTEST time in CD history.
And in a Damaged/Burning building as well.
QUOTE (atmosphere+Nov 25 2007, 02:41 PM)
-fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
All true, but SO WHAT?
QUOTE (atmosphere+Nov 25 2007, 02:41 PM)
- Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
NO, it didn't.
It had a SUPERFICAL appearance of a controlled demolition.
It was not preceeded by a lot of men entering the building for days and days stringing explosives and det cord as ALL other CDs are.
The building was burning out of control for 7 hours like no other CD.
There were no Shockwave sounds from all the HE going off.
There was no high speed ejecta from the HE prior to the collapse.
The collapse took a long time (~ 18 secs, with the damage spreading through the structure relatively slowly well before the final curtain wall came down) much more indicitive of a progressive strutural collapse (IMHO) than a HE induced CD (particularly if the CD has to be hurried because of the building conditions).
QUOTE (atmosphere+Nov 25 2007, 02:41 PM)
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are my claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
That's apparently coming this spring.
There will be a public comment period on a draft report prior to that.
The current LACK of the NIST report on the WTC 7 collapse is NOT evidence of a CD though.
The WTC Tower steel, because they were building two almost identical buildings, and because the gross dimensions remained the same as you went up but the cross sections got smaller, was stamped with a building/floor code.
Hence one could tell from the stamp that it was WTC 1 or 2 steel.
There was no such stamp on the WTC 7 steel, thus the identification of steel once it left the site was problematic. I suspect this issue will be covered in the final WTC 7 report.
As to Jowenko, has HE written a peer reviewed paper explaining why he's CERTAIN it was CD? I must admit, all I've heard is his video and that is not at all convincing.
Your claim ISN'T as wild as claiming that explosives were planted before 9/11. Considering the building burnt for 7 hours out of control, that idea is so dumb it hardly warrents comment and you will only find your typical fringe loonies who will publicly support pre-planted explosives in WTC 7.
Arthur
QUOTE (atmosphere+Nov 25 2007, 06:51 PM)
Jowenko Explosieve Demolitie BV
Veersewg 107
4351SL Veere
tel.(0118)612735
fax.(0118)612779
He lives just 3 miles away from me , so it wasn't very hard to find his number.
That is great I just want to ask what explosive he has that defies the physical constants and laws of the universe, that is all.
I tested both TNT and RDX in high sulfur diesel fuel fires, and in impacts it is unlikely that they survive either.
RDX degrading was especially venerable to the high sulfur diesel fuel fires.
Also there were most probably problems in the power station under 7 and transformer shorting might have been common down there in fact I may have found some evidence of that!
I do not think that armored shaped charges could even survive those conditions, I just wanted to know what Jowenko thinks will work and patent it in the USA I can make a bundle.
If you want you can copy this post and have him answer those questions and see if he can come up with an answer it would save me a phone call and valuable time.
I have copied the Number and indeed intend on calling as soon as possible.
Veersewg 107
4351SL Veere
tel.(0118)612735
fax.(0118)612779
He lives just 3 miles away from me , so it wasn't very hard to find his number.
That is great I just want to ask what explosive he has that defies the physical constants and laws of the universe, that is all.
I tested both TNT and RDX in high sulfur diesel fuel fires, and in impacts it is unlikely that they survive either.
RDX degrading was especially venerable to the high sulfur diesel fuel fires.
Also there were most probably problems in the power station under 7 and transformer shorting might have been common down there in fact I may have found some evidence of that!
I do not think that armored shaped charges could even survive those conditions, I just wanted to know what Jowenko thinks will work and patent it in the USA I can make a bundle.
If you want you can copy this post and have him answer those questions and see if he can come up with an answer it would save me a phone call and valuable time.
I have copied the Number and indeed intend on calling as soon as possible.
QUOTE (atmosphere+Nov 25 2007, 02:57 PM)
there are lots of way's a demolition company can be involved with the government .
So what?
That doesn't mean the Govt can control what the EMPLOYEES of the demolition company say to the press.
And if they DID talk, there is NO WAY the Govt could then hold it against the company.
Between the Govt Acct Office (GAO) and the bidding process for govt contracts, and contract law, pretty much prevents the kind of Govt coersion you seem to think is rampant in the US.
You have YET to give any reasonable explanation as to why the supposedly HEROIC acts of these brave men would be covered up.
You haven't even given a reasonable explanation as to why the Govt would want to cover it up.
Arthur
So what?
That doesn't mean the Govt can control what the EMPLOYEES of the demolition company say to the press.
And if they DID talk, there is NO WAY the Govt could then hold it against the company.
Between the Govt Acct Office (GAO) and the bidding process for govt contracts, and contract law, pretty much prevents the kind of Govt coersion you seem to think is rampant in the US.
You have YET to give any reasonable explanation as to why the supposedly HEROIC acts of these brave men would be covered up.
You haven't even given a reasonable explanation as to why the Govt would want to cover it up.
Arthur
QUOTE (adoucette+Nov 25 2007, 02:23 PM)
You haven't even given a reasonable explanation as to why the Govt would want to cover it up.
There were at least three governments or quasi=govenments involved: USG, NYCG, PANYNJ. Maybe also NYG.
Is he trying to say all of them were in on it?
There were at least three governments or quasi=govenments involved: USG, NYCG, PANYNJ. Maybe also NYG.
Is he trying to say all of them were in on it?
QUOTE (atmosphere+Nov 25 2007, 07:41 PM)
-Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree?
-Fact is WTC 7 had relatively few columns
-fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
- Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are my claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
Fact is a building like WTC 7 can be brought down with explosives planted only on the first few floors , agree? [U] All you have to do is take out the weak cantilever beam structure, [/U]-Fact is WTC 7 had relatively few columns
Again the cantilever beam structure is all that has to be taken out.-
fact is nobody knew for sure it was going to collapse, and if it did ,how and when it would collapse.
Wrong there were signs of the building leaning to wards the damaged side near world trade 6
-fact is an uncontrolled collapse can cause a lot of damage to surrounding buildings .
[U]True but not really a concern as most of the structures were evacuated and most were already damaged, setting off charges in a building before doing a full damage assessment.
IS Like going into a rocket ship that has a leaking hydrogen tank after the main engines are ignited, it is just dumb. [/U]
-Fact is that fires will spread to the floors above when nobody fights them and the sprinkler system is broken.
Fact is diesel fuel flowing down elevator shafts runs to the lowest part where there were electrical transformers that were energized and could possibly short. -
Fact is that the collapse has the appearance of a controlled demolition( doesn't proof anything, I know) , and also had the results of a controlled demolition.
-Fact is that there is no peer reviewed paper explaining the collapse based on facts , I've only seen "probable cause of collapse " papers .
[B]That is true but doesn't point to controlled demolition all that points to is lack of a peer reviewed paper![/B]A serious question : Is there any steel recovered for investigation ? NIST had lots of steel from the towers to investigate is this also the case with building 7's investigation ? I'm get conflicting answers to this question so far .
There is some, I believe however building 7 was not even considered important in early investigations because of cause and effect perimeters. Building 7 was only treated as a curiosity in the inital investigation because no lives were lost in that building, and if the towers never fell it would not have been damaged at all reguardless of anything done after! Jowenko does not base his opinion on just a video , he analyzed the damage reports and the buildings structure and more .
Why are mI do not believe he acturately understands the conditions that were in the buildings. y claims 'wild" . I think its more wild to claim explosives were planted before 9/11.
I believe it is wild to believe the explosives were planted at all. [/U]
QUOTE (atmosphere+Nov 25 2007, 07:57 PM)
there are lots of way's a demolition company can be involved with the government . Just a few examples :
Demolition Inc., was subcontracted by Tully Construction to coordinate the removal of rubble from Ground Zero and the disposal of the structural steel in the months following the attack.
atmosphere
When did you and Jowenko start investigating building 7, what date? please I want to see how much time you actually spent on this reviewing all the evidence?
Please Humor me in this, please.
Demolition Inc., was subcontracted by Tully Construction to coordinate the removal of rubble from Ground Zero and the disposal of the structural steel in the months following the attack.
atmosphere
When did you and Jowenko start investigating building 7, what date? please I want to see how much time you actually spent on this reviewing all the evidence?
Please Humor me in this, please.
I revised the computation of the stretch to involve another parameter, representing the minimum stretch.
s(Z,S) = (s0-s2)exp(-s1*Z*S*S) + s2
With the B&V crush-down equation, s0 = 0.5008, s2 = 0.0061. (s2 is smaller than the minimum observed of 0.047)
With the Seffen crush-down equation, s0 = 0.4933, s2 = 0.0459.
These results suggest that the minimum stretch was reached rather rapidly during the collapse of WTC 1.
s(Z,S) = (s0-s2)exp(-s1*Z*S*S) + s2
With the B&V crush-down equation, s0 = 0.5008, s2 = 0.0061. (s2 is smaller than the minimum observed of 0.047)
With the Seffen crush-down equation, s0 = 0.4933, s2 = 0.0459.
These results suggest that the minimum stretch was reached rather rapidly during the collapse of WTC 1.
atmosphere
I am in the Central time zone what time would be the best to call,
Jowenko?
I really do want to ask him how you set the explosives in the case of buildings 7 since I know that even the soot in the buildings can cause an explosion that can set the charges off when they are being installed.
I am in the Central time zone what time would be the best to call,
Jowenko?
I really do want to ask him how you set the explosives in the case of buildings 7 since I know that even the soot in the buildings can cause an explosion that can set the charges off when they are being installed.
QUOTE (David B. Benson+Nov 25 2007, 03:59 PM)
I revised the computation of the stretch to involve another parameter, representing the minimum stretch.
s(Z,S) = (s0-s2)exp(-s1*Z*S*S) + s2
With the B&V crush-down equation, s0 = 0.5008, s2 = 0.0061. (s2 is smaller than the minimum observed of 0.047)
With the Seffen crush-down equation, s0 = 0.4933, s2 = 0.0459.
These results suggest that the minimum stretch was reached rather rapidly during the collapse of WTC 1.
But no. For both crush-down equations, the stretch at 3.82 seconds is 0.266, i.e., about one-half or a bit more of the initial value.
Edited to add: For a better choice of parameters, the minimum stretch is taken as 0.0781 (B&V), 0.1063 (Seffen), which seems quite reasonable in light of the discussion here. And also, the standard deviation decreases to 0.182, i.e., seven-tenths of a pixel.
s(Z,S) = (s0-s2)exp(-s1*Z*S*S) + s2
With the B&V crush-down equation, s0 = 0.5008, s2 = 0.0061. (s2 is smaller than the minimum observed of 0.047)
With the Seffen crush-down equation, s0 = 0.4933, s2 = 0.0459.
These results suggest that the minimum stretch was reached rather rapidly during the collapse of WTC 1.
But no. For both crush-down equations, the stretch at 3.82 seconds is 0.266, i.e., about one-half or a bit more of the initial value.
Edited to add: For a better choice of parameters, the minimum stretch is taken as 0.0781 (B&V), 0.1063 (Seffen), which seems quite reasonable in light of the discussion here. And also, the standard deviation decreases to 0.182, i.e., seven-tenths of a pixel.
Is someone claiming they heard detonations going off in WTC7, or are these more of the "silent ninja explosives" that the CDiots seem to think are readily-available?
Also, one of the main concerns that professional controlled-demolition teams have is the flying debris (especially broken glass) that can travel hundreds of yards, which is one reason they strictly enforce removing all glass from buildings they're demolishing, and strict enforcement of perimeter control, keeping civilians FAR away from any CD. Is there any evidence AT ALL that anyone tried removing the windows or keeping civilians at a safe distance? Failure to do so would expose the CD company to unlimited liability, if a shard of broken glass flew 200 yards and hitting someone in the eye, they could easily sue for millions of dollars and easily win the lawsuit. The CD company would lose its license for violating established safe-practices. Negotiating the liability release contract would, itself, require more time than it took for WTC7 to collapse on its own. Lawyers on both sides would have to be involved. Nothing fast happens when lawyers are involved. (That was the problem with Katrina, the rescue effort was organized by lawyers, and the doctors/nurses who stayed behind and did their honest best-efforts to provide the best-possible health care for the Katrina victims are facing malpractice lawsuits for violating health care protocols designed for perfectly-operating hospitals, and the flooding conditions rendered those protocols impossible to implement. The smart doctors simply abandoned their posts, the ones who stayed behind are the ones who got in trouble,)
Also, one of the main concerns that professional controlled-demolition teams have is the flying debris (especially broken glass) that can travel hundreds of yards, which is one reason they strictly enforce removing all glass from buildings they're demolishing, and strict enforcement of perimeter control, keeping civilians FAR away from any CD. Is there any evidence AT ALL that anyone tried removing the windows or keeping civilians at a safe distance? Failure to do so would expose the CD company to unlimited liability, if a shard of broken glass flew 200 yards and hitting someone in the eye, they could easily sue for millions of dollars and easily win the lawsuit. The CD company would lose its license for violating established safe-practices. Negotiating the liability release contract would, itself, require more time than it took for WTC7 to collapse on its own. Lawyers on both sides would have to be involved. Nothing fast happens when lawyers are involved. (That was the problem with Katrina, the rescue effort was organized by lawyers, and the doctors/nurses who stayed behind and did their honest best-efforts to provide the best-possible health care for the Katrina victims are facing malpractice lawsuits for violating health care protocols designed for perfectly-operating hospitals, and the flooding conditions rendered those protocols impossible to implement. The smart doctors simply abandoned their posts, the ones who stayed behind are the ones who got in trouble,)
QUOTE (wcelliott+Nov 26 2007, 04:08 AM)
Is someone claiming they heard detonations going off in WTC7, or are these more of the "silent ninja explosives" that the CDiots seem to think are readily-available?
Also, one of the main concerns that professional controlled-demolition teams have is the flying debris (especially broken glass) that can travel hundreds of yards, which is one reason they strictly enforce removing all glass from buildings they're demolishing, and strict enforcement of perimeter control, keeping civilians FAR away from any CD. Is there any evidence AT ALL that anyone tried removing the windows or keeping civilians at a safe distance? Failure to do so would expose the CD company to unlimited liability, if a shard of broken glass flew 200 yards and hitting someone in the eye, they could easily sue for millions of dollars and easily win the lawsuit. The CD company would lose its license for violating established safe-practices. Negotiating the liability release contract would, itself, require more time than it took for WTC7 to collapse on its own. Lawyers on both sides would have to be involved. Nothing fast happens when lawyers are involved. (That was the problem with Katrina, the rescue effort was organized by lawyers, and the doctors/nurses who stayed behind and did their honest best-efforts to provide the best-possible health care for the Katrina victims are facing malpractice lawsuits for violating health care protocols designed for perfectly-operating hospitals, and the flooding conditions rendered those protocols impossible to implement. The smart doctors simply abandoned their posts, the ones who stayed behind are the ones who got in trouble,)
Hi wcelliot!
And not only 'flying glass' shards, either!
Some years ago here in Australia, in our ACT (Australian Capital Territory), there was a controlled demo which produced flying chunks of concrete that hit (and killed one of!) many spectators that had collected ACROSS THE RIVER many hundreds of meters away....supposedly in a 'safe zone'!
Such is the force/hazard of High Explosives 'sloppily/hastily' placed, even though they had PLENTY of time to place them and cleared the building of any loose/glass etc materials beforehand.
Gotta run. Cheers all!
RC.
.
Also, one of the main concerns that professional controlled-demolition teams have is the flying debris (especially broken glass) that can travel hundreds of yards, which is one reason they strictly enforce removing all glass from buildings they're demolishing, and strict enforcement of perimeter control, keeping civilians FAR away from any CD. Is there any evidence AT ALL that anyone tried removing the windows or keeping civilians at a safe distance? Failure to do so would expose the CD company to unlimited liability, if a shard of broken glass flew 200 yards and hitting someone in the eye, they could easily sue for millions of dollars and easily win the lawsuit. The CD company would lose its license for violating established safe-practices. Negotiating the liability release contract would, itself, require more time than it took for WTC7 to collapse on its own. Lawyers on both sides would have to be involved. Nothing fast happens when lawyers are involved. (That was the problem with Katrina, the rescue effort was organized by lawyers, and the doctors/nurses who stayed behind and did their honest best-efforts to provide the best-possible health care for the Katrina victims are facing malpractice lawsuits for violating health care protocols designed for perfectly-operating hospitals, and the flooding conditions rendered those protocols impossible to implement. The smart doctors simply abandoned their posts, the ones who stayed behind are the ones who got in trouble,)
Hi wcelliot!
And not only 'flying glass' shards, either!
Some years ago here in Australia, in our ACT (Australian Capital Territory), there was a controlled demo which produced flying chunks of concrete that hit (and killed one of!) many spectators that had collected ACROSS THE RIVER many hundreds of meters away....supposedly in a 'safe zone'!
Such is the force/hazard of High Explosives 'sloppily/hastily' placed, even though they had PLENTY of time to place them and cleared the building of any loose/glass etc materials beforehand.
Gotta run. Cheers all!
RC.
.
When wtc7 was going to collapse, they cleared the streets, a collapse zone has been set up. Theoretically in a gravitational collapse no material can reach ground zero further away than the highest height, i.e. 174 meter in the wtc7 case.
QUOTE (einsteen+Nov 26 2007, 06:25 AM)
When wtc7 was going to collapse, they cleared the streets, a collapse zone has been set up. Theoretically in a gravitational collapse no material can reach ground zero further away than the highest height, i.e. 174 meter in the wtc7 case.
It seems wtc7 was in fact a controlled demolition due to its rapid descent and sudden movement.
Here is WTC 7 Compared to CD
The same can be said of the Twin Towers.
North Tower Compared to CD
In this video the comparison is rich. Both buildings display large plumes of exploding debris in a horizontal line followed by the appearance of zero resistance to the imploding structure.
It seems wtc7 was in fact a controlled demolition due to its rapid descent and sudden movement.
Here is WTC 7 Compared to CD
The same can be said of the Twin Towers.
North Tower Compared to CD
In this video the comparison is rich. Both buildings display large plumes of exploding debris in a horizontal line followed by the appearance of zero resistance to the imploding structure.
QUOTE (einsteen+Nov 24 2007, 09:11 PM)
Shagster, how did you derive that equation, this is only valid for constant acceleration, but at the end if E1 is constant then the ratio E1/m(y) becomes infinite. The exact limit can be determined with the Bazant crush-up equation, I ran a simple vbscript and concluded that the E1/mass ratio was about 4 times more than the ones of wtc1,2, I could be completely wrong but it should be more because the building was massively strong, designed to survive earthquakes.
I solved the crush-up diffeq for the case of F/m being a constant and then expressing resistive force F as the ratio E1/h.
I've also used numerical solutions for the crush-up equation and a discrete algebraic model.
I solved the crush-up diffeq for the case of F/m being a constant and then expressing resistive force F as the ratio E1/h.
I've also used numerical solutions for the crush-up equation and a discrete algebraic model.
The crush-up diffeq is derived in the BV paper. The crush-up diffeq for zero stretch is:
y'' = -g + F/m
where y is the distance from the ground level to the top of the building and g is acceleration due to gravity. F is the resistive force and m is the mass of the falling section at any given instant.
If F/m is considered constant, then every term on the right side of the diffeq above is a constant.
The boundary conditions for a collapse that starts at the ground level with zero velocity are:
v=y'=0 at t=0
y=H at t=0
where H is the original building height. y is zero at the end of collapse. Integrating the crush-up differential equation twice and applying the boundary conditions gives the solution and collapse duration:
t = sqrt(2H/[g-(F/m)])
For F=0, the collapse occurs at free-fall rate and the duration is:
t = sqrt(2H/g)
E1 is the integral of F through a distance of the inter-story height h. Resistive force F at a particular position in the tower can be expressed as an energy E1 divided by h at that position. To be mathematically pure, one would use a differential dE1/dh to describe the resistive force at a particular point. For a tower with many stories and where F changes gradually, E1/h is sufficient.
If F/m is considered constant and h is a constant, then F/m can be expressed as E1/mh which is also a constant.
t = sqrt(2H/[g-(E1/mh)])
When E1/mh is a constant, E1 decreases with building height in a way that keeps E1/mh constant. For a tower where all stories have the same mass, E1 at mid-tower height would be half of its value at the ground level, because the mass above the mid-tower height is half the total tower mass.
When E1/mh is constant during a crush-up, the acceleration is constant throughout the collapse and the collapse goes to completion.
y'' = -g + F/m
where y is the distance from the ground level to the top of the building and g is acceleration due to gravity. F is the resistive force and m is the mass of the falling section at any given instant.
If F/m is considered constant, then every term on the right side of the diffeq above is a constant.
The boundary conditions for a collapse that starts at the ground level with zero velocity are:
v=y'=0 at t=0
y=H at t=0
where H is the original building height. y is zero at the end of collapse. Integrating the crush-up differential equation twice and applying the boundary conditions gives the solution and collapse duration:
t = sqrt(2H/[g-(F/m)])
For F=0, the collapse occurs at free-fall rate and the duration is:
t = sqrt(2H/g)
E1 is the integral of F through a distance of the inter-story height h. Resistive force F at a particular position in the tower can be expressed as an energy E1 divided by h at that position. To be mathematically pure, one would use a differential dE1/dh to describe the resistive force at a particular point. For a tower with many stories and where F changes gradually, E1/h is sufficient.
If F/m is considered constant and h is a constant, then F/m can be expressed as E1/mh which is also a constant.
t = sqrt(2H/[g-(E1/mh)])
When E1/mh is a constant, E1 decreases with building height in a way that keeps E1/mh constant. For a tower where all stories have the same mass, E1 at mid-tower height would be half of its value at the ground level, because the mass above the mid-tower height is half the total tower mass.
When E1/mh is constant during a crush-up, the acceleration is constant throughout the collapse and the collapse goes to completion.
QUOTE (NEU-FONZE+Nov 23 2007, 01:06 PM)
Shagster:
In my latest foray on the WTC 7 problem I ran my spreadsheet program with the following parameters:
40 floors in crush up mode.
Mass of 40 floors = 185,454,560 kg
Height of 1 floor = 3.96 meters
E1 = 1.8 GJ (To allow for extra strength of WTC 7 vs. WTC 1 & 2)
I let E1 decrease somewhat going down the building (Sorry I don't have the exact numbers handy)
Collapse time = 6.65 seconds (Then you have to consider what happens to the 7 floors at the base of the building!)
The effective g over the first half of the collapse is over 7 m/s^2 which is higher than WTC 1 & 2 because WTC 7 had the heaviest hammer (3 times heavier than WTC 1)
The height vs. time plot shows a nice up-turn at the end of the collapse profile, (unlike WTC 1 & 2 which show a monotonic increase all the way down).
I've also used a discrete algebraic crush-up model for WTC7 which has given similar results to what you posted. It allows one to change E1 and story mass on a story-by-story basis, which makes it more flexible than the simplified diffeq crush-up model that I posted about earlier.
The values that you used in a discrete model can be tried in the simplified diffeq crush-up model with E1/mh being a constant. That means E1 decreases linearly up the tower and is proportional to the mass above the collapse front. That's similar to your decrease of E1 with building height but not exactly the same.
Using your values with E1 taken as the value at the bottom of the 40 stories,
E1/mh = 1.8GJ/(185E6kg*3.96m) = 2.45 m/s^2
The diffeq crush-up model for constant E1/mh is
t = sqrt(2H/[g-E1/(mh)])
t = sqrt(2*40*3.96 / [9.81-2.45])
t = 6.6 s
That's close to your value of 6.65 s in your algebraic model.
The acceleration in this model is constant throughout collapse and is
9.81 - 2.45 = 7.36 m/s^2
That's also close to the acceleration of 7 m/s2 during the first half of the collapse in your algebraic model.
In my latest foray on the WTC 7 problem I ran my spreadsheet program with the following parameters:
40 floors in crush up mode.
Mass of 40 floors = 185,454,560 kg
Height of 1 floor = 3.96 meters
E1 = 1.8 GJ (To allow for extra strength of WTC 7 vs. WTC 1 & 2)
I let E1 decrease somewhat going down the building (Sorry I don't have the exact numbers handy)
Collapse time = 6.65 seconds (Then you have to consider what happens to the 7 floors at the base of the building!)
The effective g over the first half of the collapse is over 7 m/s^2 which is higher than WTC 1 & 2 because WTC 7 had the heaviest hammer (3 times heavier than WTC 1)
The height vs. time plot shows a nice up-turn at the end of the collapse profile, (unlike WTC 1 & 2 which show a monotonic increase all the way down).
I've also used a discrete algebraic crush-up model for WTC7 which has given similar results to what you posted. It allows one to change E1 and story mass on a story-by-story basis, which makes it more flexible than the simplified diffeq crush-up model that I posted about earlier.
The values that you used in a discrete model can be tried in the simplified diffeq crush-up model with E1/mh being a constant. That means E1 decreases linearly up the tower and is proportional to the mass above the collapse front. That's similar to your decrease of E1 with building height but not exactly the same.
Using your values with E1 taken as the value at the bottom of the 40 stories,
E1/mh = 1.8GJ/(185E6kg*3.96m) = 2.45 m/s^2
The diffeq crush-up model for constant E1/mh is
t = sqrt(2H/[g-E1/(mh)])
t = sqrt(2*40*3.96 / [9.81-2.45])
t = 6.6 s
That's close to your value of 6.65 s in your algebraic model.
The acceleration in this model is constant throughout collapse and is
9.81 - 2.45 = 7.36 m/s^2
That's also close to the acceleration of 7 m/s2 during the first half of the collapse in your algebraic model.
NF,
If I did the math correctly, the value of E1 that you used for WTC7 is about 63% higher than the value you used for WTC2. E1=1.8GJ is supporting 40 stories in the case of WTC7 compared with E1=0.8GJ supporting 29 stories for WTC2. For the same mass per story for WTC7 and the towers,
(1.8/40) / (0.8/29) = 1.63
Even with that higher value of E1 for WTC7 compared with the towers, the crush-up models for WTC7 still show a collapse duration of about 6.6 seconds, which is close to the observed duration of the final global collapse of WTC7.
There are still the other 7 stories, so the E1 value for 40 stories may have been a little lower than 1.8 GJ.
If I did the math correctly, the value of E1 that you used for WTC7 is about 63% higher than the value you used for WTC2. E1=1.8GJ is supporting 40 stories in the case of WTC7 compared with E1=0.8GJ supporting 29 stories for WTC2. For the same mass per story for WTC7 and the towers,
(1.8/40) / (0.8/29) = 1.63
Even with that higher value of E1 for WTC7 compared with the towers, the crush-up models for WTC7 still show a collapse duration of about 6.6 seconds, which is close to the observed duration of the final global collapse of WTC7.
There are still the other 7 stories, so the E1 value for 40 stories may have been a little lower than 1.8 GJ.
QUOTE (shagster+Nov 26 2007, 09:19 AM)
I solved the crush-up diffeq for the case of F/m being a constant and then expressing resistive force F as the ratio E1/h.
I've also used numerical solutions for the crush-up equation and a discrete algebraic model.
Cool, doesn't that give a constant effective acceleration? Maybe a small correction then should be added. I remember that you did a lot of work in the past, are you ever going to put that online at a central point ? I also hope to see DBBs work once somewhere.
ps.
I posted this before reading your latest posts, yeah I once wrote a similar relation (for constant acceleration) between E1,h,m,g, DBB found the 400MJ surprisingly good, because compaction was ignored.
Einsteen,
Do have software that automatically tiles those stills into a checkboard pattern?
Do have software that automatically tiles those stills into a checkboard pattern?
QUOTE (einsteen+Nov 26 2007, 09:41 AM)
Cool, doesn't that give a constant effective acceleration? Maybe a small correction then should be added. I remember that you did a lot of work in the past, are you ever going to put that online at a central point ? I also hope to see DBBs work once somewhere.
Yes, the acceleration is constant in that type of model. It's not necessarily a more accurate model. It's simple and doesn't require solving a diffeq using numerical methods and doesn't require a program to solve a discrete algebraic model. It also gives some insight into the meaning of E1/mh.
I've been meaning to put up a webpage. I've discussed it with DBB and others. Perhaps DBB and I could put up a webpage together.
Yes, the acceleration is constant in that type of model. It's not necessarily a more accurate model. It's simple and doesn't require solving a diffeq using numerical methods and doesn't require a program to solve a discrete algebraic model. It also gives some insight into the meaning of E1/mh.
I've been meaning to put up a webpage. I've discussed it with DBB and others. Perhaps DBB and I could put up a webpage together.
The total amount of falling mass that is being resisted by 400 MJ per story needs to be known. The ratio of F/m or E1/m is what matters. I don't remember offhand what value of mass for the upper block that DBB was using.
QUOTE (shagster+Nov 26 2007, 09:41 AM)
Einsteen,
Do have software that automatically tiles those stills into a checkboard pattern?
I guess checkboard is chessboard. OneWhiteEye gave me some scripts to merge 1xN bitmaps but I didn't use that for this.
If you have jpg/bmp/gif files. for example 001.bmp, 002.bmp etc then create
a blank text file with the extension .html or .htm and place for example the following into it
Then open the html file with internet explorer and adjusting the width you
can determine how it appears. I'm sure with OneWhiteEye's script it can be
done with a mouseclick, but I never went deep into Ruby (this last part could be taken out of context, lol), this is what I mean
and so on, and then making a screendump, primitive but it works.
ps. it looks like they have the same width here
Do have software that automatically tiles those stills into a checkboard pattern?
I guess checkboard is chessboard. OneWhiteEye gave me some scripts to merge 1xN bitmaps but I didn't use that for this.
If you have jpg/bmp/gif files. for example 001.bmp, 002.bmp etc then create
a blank text file with the extension .html or .htm and place for example the following into it
CODE
<img src="001.bmp">
<img src="002.bmp">
...
<img src="999.bmp">
<img src="002.bmp">
...
<img src="999.bmp">
Then open the html file with internet explorer and adjusting the width you
can determine how it appears. I'm sure with OneWhiteEye's script it can be
done with a mouseclick, but I never went deep into Ruby (this last part could be taken out of context, lol), this is what I mean
and so on, and then making a screendump, primitive but it works.
ps. it looks like they have the same width here
Shagster:
Thanks for your excellent posts on the theory of crush-up calculations as in WTC 7.
I am trying to remember why I used 1.8 GJ for the E1 in WTC 7! ( Do I have early-stage Alzheimers? I hope not!!)
However, I do believe WTC 7 was a heavier type of construction than the twin towers...
Do you have any info on this?
Thanks for your excellent posts on the theory of crush-up calculations as in WTC 7.
I am trying to remember why I used 1.8 GJ for the E1 in WTC 7! ( Do I have early-stage Alzheimers? I hope not!!)
However, I do believe WTC 7 was a heavier type of construction than the twin towers...
Do you have any info on this?
QUOTE (NEU-FONZE+Nov 26 2007, 08:00 AM)
However, I do believe WTC 7 was a heavier type of construction than the twin towers...
Unlikely, IMO. Engineers build the lightest structure which is supposed to stand up under the expected loads. In particular, the wind load on WTC 7 would be less than the towers.
It is true that most of WTC 7 used post-n-beam construction, rather than trusses, but there was, IMHO, a rather large distance between the beams.
Unlikely, IMO. Engineers build the lightest structure which is supposed to stand up under the expected loads. In particular, the wind load on WTC 7 would be less than the towers.
It is true that most of WTC 7 used post-n-beam construction, rather than trusses, but there was, IMHO, a rather large distance between the beams.
WTC 7 had a VERY complex structure and there is no easy way to describe it as it really started out as a MUCH smaller building and then was modified into the building we call WTC 7
See http://www.fema.gov/pdf/library/fema403_ch5.pdf
It will give you an idea of the complex construction involved in the tower.
It will also give you an idea of why this has been a difficult analysis.
Arthur
See http://www.fema.gov/pdf/library/fema403_ch5.pdf
It will give you an idea of the complex construction involved in the tower.
It will also give you an idea of why this has been a difficult analysis.
Arthur
QUOTE (memeticverb+Nov 26 2007, 12:17 AM)
It seems wtc7 was in fact a controlled demolition due to its rapid descent and sudden movement.
The same can be said of the Twin Towers.
... the appearance of zero resistance to the imploding structure.
Might seem that way, but that doesn't take into account the damage and subsequent fires.
Same here. Damage plus fires.
Nope. Actual measurements have been taken for the first few seconds and the resistance is greater than zero by a substantial margin.
The same can be said of the Twin Towers.
... the appearance of zero resistance to the imploding structure.
Might seem that way, but that doesn't take into account the damage and subsequent fires.
Same here. Damage plus fires.
Nope. Actual measurements have been taken for the first few seconds and the resistance is greater than zero by a substantial margin.
Hello to all,
Can anyone tell me when I can post links to this forum?
Can anyone tell me when I can post links to this forum?
Is it after a certain number of posts or something?
I put together a post with some pictures and links, which isn't effective without them.
I don't know how many posts you have to make before links are allowed. Not too many. You can put them in without the prefix, as in www.xxxx.com, in the meantime.
QUOTE (David B. Benson+Nov 25 2007, 12:38 AM)
Rather dull reading, but perhaps somebody will care to graph the measured and calculated drops versus time.
The measured and calculated values, when plotted together, pretty much lay on top of each other so that isn't too illuminating. Here is a stacked plot; from bottom to top this is measured, calculated, the difference resulting from measured minus calculated, and the difference divided by the sum of measured and calculated values.
http://i13.tinypic.com/81hit6c.png
The measured and calculated values, when plotted together, pretty much lay on top of each other so that isn't too illuminating. Here is a stacked plot; from bottom to top this is measured, calculated, the difference resulting from measured minus calculated, and the difference divided by the sum of measured and calculated values.
http://i13.tinypic.com/81hit6c.png
thanks onewhiteeye
QUOTE (OneWhiteEye+Nov 26 2007, 05:39 PM)
The measured and calculated values, when plotted together, pretty much lay on top of each other so that isn't too illuminating. Here is a stacked plot; from bottom to top this is measured, calculated, the difference resulting from measured minus calculated, and the difference divided by the sum of measured and calculated values.
http://i13.tinypic.com/81hit6c.png
Thank you! Quite useful!
http://i13.tinypic.com/81hit6c.png
Thank you! Quite useful!
maybe after 10? 
QUOTE (David B. Benson+Nov 27 2007, 01:08 AM)
Thank you! Quite useful!
You're welcome.
hardlines, why not hop over to some useless thread, pop in a half-dozen character attacks, then come back here and try to post your goods?
You're welcome.
hardlines, why not hop over to some useless thread, pop in a half-dozen character attacks, then come back here and try to post your goods?
QUOTE (OneWhiteEye+Nov 27 2007, 01:12 AM)
You're welcome.
hardlines, why not hop over to some useless thread, pop in a half-dozen character attacks, then come back here and try to post your goods?
yeah might have to, it ain't after 10
hardlines, why not hop over to some useless thread, pop in a half-dozen character attacks, then come back here and try to post your goods?
yeah might have to, it ain't after 10
shagster, NEU-FONZE, einsteen: great discussion, very interesting.
Well, still no good after 20 posts, thats enough spamming for me for one day.
Maybe later, won't be the same with showing the images.
Maybe later, won't be the same with showing the images.
The exact determination of E1/M for wtc7
using the discrete Bazant/Greening model
Ok this is a quick attempt.. not using a constant acceleration and I have no LaTeX at the moment...
It has 47 stories above ground zero and started in fact with
v0=0
Then for the next speed we have
v1^2=v_0^2+2(gh-E1/47m)
with E1 the famous energy value, m the mass of a floor, E1,m constant
throughout the whole building, further
h=147/47
g=9.80665
Then the recursive relation gives
v2^2=v1^2+2(gh-E1/46m)=2(gh-E1/47m)+2(gh-E1/46m)
v3^2=v2^2+2(gh-E1/45m)=2(gh-E1/47m)+2(gh-E1/46m)+2(gh-E1/45m)
and so on.
This means that if we arrive at story n, we get
vn^2=2gh*n-2(E1/m)[1/(48-n)+...+1/47]
for the speed at that place.
The total collapse time then is (for a parabole the time is exactly the ratio of
h and the average speed), that will be (for wtc1,2 that cannot be done)
T=2h/(v0+v1)+2h/(v1+v2)+2h/(v2+v3)+...+2h/(v46+v47)
If I use MAPLE to sum those times I get
E1/m=0 J/kg => T=5.475 seconds
E1/m=289 J/kg => T=6.504 seconds
E1/m=324 J/kg => T=6.771 seconds
For higher values of E1/m the result becomes complex which physically
means that the collapse is arrested at a certain point, that would lead to
a theoretical maximum equal to 6.771 seconds. I'm currently not sure
about this, no time to think, the math says it.
The Maple plot gives
http://i6.tinypic.com/87lr8tl.gif
If the collapse time is 6.5 seconds then multiplication with 47 leads to
E1/M=6.14 J/kg
That is the same value that I determined with my crappy visual basic script if I remember well. For wtc1,2 this was roughly 1.5 J/kg
If the analysis is correct then we can conclude wtc7 was extremely strong.
using the discrete Bazant/Greening model
Ok this is a quick attempt.. not using a constant acceleration and I have no LaTeX at the moment...
It has 47 stories above ground zero and started in fact with
v0=0
Then for the next speed we have
v1^2=v_0^2+2(gh-E1/47m)
with E1 the famous energy value, m the mass of a floor, E1,m constant
throughout the whole building, further
h=147/47
g=9.80665
Then the recursive relation gives
v2^2=v1^2+2(gh-E1/46m)=2(gh-E1/47m)+2(gh-E1/46m)
v3^2=v2^2+2(gh-E1/45m)=2(gh-E1/47m)+2(gh-E1/46m)+2(gh-E1/45m)
and so on.
This means that if we arrive at story n, we get
vn^2=2gh*n-2(E1/m)[1/(48-n)+...+1/47]
for the speed at that place.
The total collapse time then is (for a parabole the time is exactly the ratio of
h and the average speed), that will be (for wtc1,2 that cannot be done)
T=2h/(v0+v1)+2h/(v1+v2)+2h/(v2+v3)+...+2h/(v46+v47)
If I use MAPLE to sum those times I get
E1/m=0 J/kg => T=5.475 seconds
E1/m=289 J/kg => T=6.504 seconds
E1/m=324 J/kg => T=6.771 seconds
For higher values of E1/m the result becomes complex which physically
means that the collapse is arrested at a certain point, that would lead to
a theoretical maximum equal to 6.771 seconds. I'm currently not sure
about this, no time to think, the math says it.
The Maple plot gives
http://i6.tinypic.com/87lr8tl.gif
If the collapse time is 6.5 seconds then multiplication with 47 leads to
E1/M=6.14 J/kg
That is the same value that I determined with my crappy visual basic script if I remember well. For wtc1,2 this was roughly 1.5 J/kg
If the analysis is correct then we can conclude wtc7 was extremely strong.
QUOTE (einsteen+Nov 27 2007, 11:43 AM)
E1=0 J/kg => T=5.475 seconds
E1/m=289 J/kg => T=6.504 seconds
E1/m=324 J/kg => T=6.771 seconds
There's a discrepancy. For E1=0, the duration for a crush up of 47 stories should be 6.02 seconds.
t = sqrt(2*H/g) = sqrt(2*47*3.78/9.81) = 6.02 s
OOOOppps Shagster, I used 147m instead of 174m.... and I cannot edit the above
Here are the corrected values:
E1/m=0 J/kg => T=5.96 seconds
E1/m=197 J/kg => T=6.50 seconds
E1/m=384 J/kg => T=7.38 seconds (maximum before the value becomes complex)
Hence
E1/M=4.19 J/kg
My vbscript (posted here) was indeed crappy because I took the 147 meter from that one.
Free fall time is sqrt(2*174/g)=5.96 seconds
Then roughly, I would say that.....
{E1/M}_{wtc7}=2.8*{E1/M}_{wtc1,wtc2}
E1/m=0 J/kg => T=5.96 seconds
E1/m=197 J/kg => T=6.50 seconds
E1/m=384 J/kg => T=7.38 seconds (maximum before the value becomes complex)
Hence
E1/M=4.19 J/kg
My vbscript (posted here) was indeed crappy because I took the 147 meter from that one.
Free fall time is sqrt(2*174/g)=5.96 seconds
Then roughly, I would say that.....
{E1/M}_{wtc7}=2.8*{E1/M}_{wtc1,wtc2}
Where did you get the value of 1.5 J/kg for WTC1 and WTC2?
Greening's model and his measured drop data for WTC2 show that E1/m is about 5.9 J/kg.
Greening's model and his measured drop data for WTC2 show that E1/m is about 5.9 J/kg.
Greening was using an E1 of about 0.8 GJ for WTC2 to make the predicted collapse curve match his measured data for the first 4 seconds. The upper block was 29 stories.
E1/m at the bottom of the upper block for that case is
E1/m = 0.8 GJ / (510E6 * 29/110) = 0.8 GJ / 134E6 kg = 5.9 J/kg
E1/m at the bottom of the upper block for that case is
E1/m = 0.8 GJ / (510E6 * 29/110) = 0.8 GJ / 134E6 kg = 5.9 J/kg
QUOTE (Chainsaw,+Nov 25 2007, 08:39 PM)
That is great I just want to ask what explosive he has that defies the physical constants and laws of the universe, that is all.
I tested both TNT and RDX in high sulfur diesel fuel fires, and in impacts it is unlikely that they survive either.
RDX degrading was especially venerable to the high sulfur diesel fuel fires.
Also there were most probably problems in the power station under 7 and transformer shorting might have been common down there in fact I may have found some evidence of that!
I do not think that armored shaped charges could even survive those conditions, I just wanted to know what Jowenko thinks will work and patent it in the USA I can make a bundle.
If you want you can copy this post and have him answer those questions and see if he can come up with an answer it would save me a phone call and valuable time.
I have copied the Number and indeed intend on calling as soon as possible.
Youre on the wrong track because Jowenko doesn't think explosives were planted before 9/11
When he heard of that theory he said the same things as you " the primairy charges cant stand heat above 250 degrees, they will detonate " and secundairy charges will burn at that temp.
I tested both TNT and RDX in high sulfur diesel fuel fires, and in impacts it is unlikely that they survive either.
RDX degrading was especially venerable to the high sulfur diesel fuel fires.
Also there were most probably problems in the power station under 7 and transformer shorting might have been common down there in fact I may have found some evidence of that!
I do not think that armored shaped charges could even survive those conditions, I just wanted to know what Jowenko thinks will work and patent it in the USA I can make a bundle.
If you want you can copy this post and have him answer those questions and see if he can come up with an answer it would save me a phone call and valuable time.
I have copied the Number and indeed intend on calling as soon as possible.
Youre on the wrong track because Jowenko doesn't think explosives were planted before 9/11
When he heard of that theory he said the same things as you " the primairy charges cant stand heat above 250 degrees, they will detonate " and secundairy charges will burn at that temp.
QUOTE (adoucette+Nov 25 2007, 08:11 PM)
Yes, but then one has to have people WILLING to go into a DAMAGED/BURNING building and PLACE the explosives and wire them so they go off at the exact same time. NO ONE saw this happen and NONE of the people who supposedly did this HEROIC act have mentioned it (for NO apparent reason)
Finally, setting the explosives on one floor to cause the building to collapse would make ONE HECK OF A BIG BANG when they went off, something that is MISSING from the videos of the collapse and from the eyewitness testimony of the people who were there at the collapse.
Not really, it had a floor area of almost an ACRE.
If it was a CD it would have been the LARGEST CD in history.
Which you claim was done in the SHORTEST time in CD history.
And in a Damaged/Burning building as well.
People entered burning buildings before that day ,buildings with larger fires .
a number of first responders report explosions
you can't compare a normal controlled demolition with the one of WTC 7 at 9/11.
For bringing down building 7 they didn't need to do all the work to prevent breaking windows of other buildings , they didn't need to blow everything into small pieces . Normally they often do this to be able to load the debris directly on trucks. These things normally take a lot of preparing time
In the polluted environment at ground zero that day all they had to do is place explosives on the central columns and or cut some in -V- shape. WTC 7 had large wide span areas and therefore relatively few columns . All of this makes a fast demolition with explosives possible .
If you bring down a building like that with explosives you end up with the same scenario as seen on 9/11
Finally, setting the explosives on one floor to cause the building to collapse would make ONE HECK OF A BIG BANG when they went off, something that is MISSING from the videos of the collapse and from the eyewitness testimony of the people who were there at the collapse.
Not really, it had a floor area of almost an ACRE.
If it was a CD it would have been the LARGEST CD in history.
Which you claim was done in the SHORTEST time in CD history.
And in a Damaged/Burning building as well.
People entered burning buildings before that day ,buildings with larger fires .
a number of first responders report explosions
you can't compare a normal controlled demolition with the one of WTC 7 at 9/11.
For bringing down building 7 they didn't need to do all the work to prevent breaking windows of other buildings , they didn't need to blow everything into small pieces . Normally they often do this to be able to load the debris directly on trucks. These things normally take a lot of preparing time
In the polluted environment at ground zero that day all they had to do is place explosives on the central columns and or cut some in -V- shape. WTC 7 had large wide span areas and therefore relatively few columns . All of this makes a fast demolition with explosives possible .
If you bring down a building like that with explosives you end up with the same scenario as seen on 9/11
Shagster, the difference is in the factor 110/29, I had to say it referred to the whole building's mass.
QUOTE (einsteen+Nov 27 2007, 05:07 PM)
Shagster, the difference is in the factor 110/29, I had to say it referred to the whole building's mass.
That assumes that the value of of E1 at the ground level of WTC2 is 0.8 GJ, the same as that for the bottom of the upper block of WTC2. E1/m for WTC2 in that case would be close to 1.5 J/kg at the base of WTC2.
That assumes that the value of of E1 at the ground level of WTC2 is 0.8 GJ, the same as that for the bottom of the upper block of WTC2. E1/m for WTC2 in that case would be close to 1.5 J/kg at the base of WTC2.
QUOTE (einsteen+Nov 27 2007, 11:43 AM)
For higher values of E1/m the result becomes complex which physically means that the collapse is arrested at a certain point, that would lead to a theoretical maximum equal to 6.771 seconds. I'm currently not sure about this, no time to think, the math says it.
That's not necessarily true. There are cases where the total collapse duration can be longer than the case for where the collapse just barely goes to completion at the top story. The crush-up may not go to completion when E1 is large enough, but it can still have a longer duration than for the case where it just barely goes to completion.
That may sound counter-intuitive, but if you solve the algebraic models or the crush-up diffeq for some various values of E1, it turns out to be the case.
QUOTE (atmosphere+Nov 27 2007, 04:31 PM)
People entered burning buildings before that day ,buildings with larger fires .
a number of first responders report explosions
you can't compare a normal controlled demolition with the one of WTC 7 at 9/11.
For bringing down building 7 they didn't need to do all the work to prevent breaking windows of other buildings , they didn't need to blow everything into small pieces . Normally they often do this to be able to load the debris directly on trucks. These things normally take a lot of preparing time
In the polluted environment at ground zero that day all they had to do is place explosives on the central columns and or cut some in -V- shape. WTC 7 had large wide span areas and therefore relatively few columns . All of this makes a fast demolition with explosives possible .
If you bring down a building like that with explosives you end up with the same scenario as seen on 9/11
Do you wish to explain to me why there would not be diesel fuel fires in the basements, and how you can prevent the explosion of transformers and the fires caused by them in the basement where the critical structures to set the charge are located right above the coned electrical distribution substation is.
Can you tell me who is dumb enough that I can hire him to set shock sensitive charges in a building where there might be an explosion at any time?
I have never seen anyone dumb enough to enter a building that might explode at any time, with explosives!
The idea of risking lives in a building where an explosion can occur to set explosives to bring the building down is not a very smart or intelligent idea now is it?
Sorry experiments have shown me that only a fool would have entered those buildings, and I do not think that demolition experts are such fools.
With diesel fuel you have the same scenario as seen on 9/11.
Fuel fires can spread downward I have seen it a number of times from leaking lines in the oil fields around here assumptions of no fires in the basements are just that assumptions.
PS. even Diesel fuel soot, carbon Black can and will explode when properly mixed with air, it is only carbon black and has similar effects to coal dust in coal mines.
You would have to be willing to commit suicide to enter those conditions, I have read about Jowenko from what I have read of his prior work I do not think him insane, that is why I wanted to call him to address these issues!
a number of first responders report explosions
you can't compare a normal controlled demolition with the one of WTC 7 at 9/11.
For bringing down building 7 they didn't need to do all the work to prevent breaking windows of other buildings , they didn't need to blow everything into small pieces . Normally they often do this to be able to load the debris directly on trucks. These things normally take a lot of preparing time
In the polluted environment at ground zero that day all they had to do is place explosives on the central columns and or cut some in -V- shape. WTC 7 had large wide span areas and therefore relatively few columns . All of this makes a fast demolition with explosives possible .
If you bring down a building like that with explosives you end up with the same scenario as seen on 9/11
Do you wish to explain to me why there would not be diesel fuel fires in the basements, and how you can prevent the explosion of transformers and the fires caused by them in the basement where the critical structures to set the charge are located right above the coned electrical distribution substation is.
Can you tell me who is dumb enough that I can hire him to set shock sensitive charges in a building where there might be an explosion at any time?
I have never seen anyone dumb enough to enter a building that might explode at any time, with explosives!
The idea of risking lives in a building where an explosion can occur to set explosives to bring the building down is not a very smart or intelligent idea now is it?
Sorry experiments have shown me that only a fool would have entered those buildings, and I do not think that demolition experts are such fools.
With diesel fuel you have the same scenario as seen on 9/11.
Fuel fires can spread downward I have seen it a number of times from leaking lines in the oil fields around here assumptions of no fires in the basements are just that assumptions.
PS. even Diesel fuel soot, carbon Black can and will explode when properly mixed with air, it is only carbon black and has similar effects to coal dust in coal mines.
You would have to be willing to commit suicide to enter those conditions, I have read about Jowenko from what I have read of his prior work I do not think him insane, that is why I wanted to call him to address these issues!
QUOTE (shagster+Nov 27 2007, 06:46 PM)
That's not necessarily true. There are cases where the total collapse duration can be longer than the case for where the collapse just barely goes to completion at the top story. The crush-up may not go to completion when E1 is large enough, but it can still have a longer duration than for the case where it just barely goes to completion.
That may sound counter-intuitive, but if you solve the algebraic models or the crush-up diffeq for some various values of E1, it turns out to be the case.
Edited:
I think that you mean that when the velocity is near zero, say 0.1 m/s and E1 is fitted in a way that it stops at the next story with v=0 then the time is h/0.05, I think that is true, but if the collapse is rapid in the beginning then that will not happen I think
That may sound counter-intuitive, but if you solve the algebraic models or the crush-up diffeq for some various values of E1, it turns out to be the case.
Edited:
I think that you mean that when the velocity is near zero, say 0.1 m/s and E1 is fitted in a way that it stops at the next story with v=0 then the time is h/0.05, I think that is true, but if the collapse is rapid in the beginning then that will not happen I think
.
Hi atmosphere, Chainsaw, wcelliot, everyone!
Re WTC7.
I thought that the 'transit' and other surveys indicated damage/instability such that it was expected to collapse at any time?
And that the ongoing diesel and widespread office fires were 'unpredictable'? Unlike 'ordinary' building fires WITHOUT such damage and ongoing dangerous conditions.
And that the ATTACKS and PANIC and loss of life ALREADY in WTC1&2 had put fire chiefs etc in the mindset of 'getting out' to avoid further loss of life.....and DAMN the buildings? Such that all concerned were merely pulled back to a safe distance to let it burn because no-one knew what ELSE may be happening to make it dangerous to do the 'usual' firefighting and cleanup until it was all over?
And in any case, the buildings were under OBSERVATION by MANY MEDIA reporters who would have noticed and EXTOLLED the 'courage' of ANYONE (let alone anyone 'loaded for demo'!) seen to enter WTC7 while everyone watched and waited for the inevitable to happen? The only 'unusual' thing seemed to be that WTC7 did NOT collapse as easily/quickly as EVERYONE expected. Such expectation by EVERYONE there, of IMMINENT COLLAPSE, would have mitigated against any decision to 'interfere', owing to the great potential for further loss of life. Can you just imagine the repercussions if thay HAD attempted to interfere with the fire and collapse progression, by attempting to demo the building, and the imminently expected collapse caught them as they were planting the necessaries?
What fire chief WHO ALREADY LOST SO MANY GOOD AND BRAVE PEOPLE IN THE DEVASTATING WTC FIRES/COLLAPSES would be STUPID and IRRESPONSIBLE enough to OK anything like that in ANOTHER HUGE BUILDING STILL ON FIRE AND MAKING CREAKING AND SNAPPING NOISES ON ALL SIDES....and which was already surveyed and judged BY FIREFIGHTING CHIEFS THEMSELVES to be in IMMINENT danger of collapse?
I'm sure they had greater sorrows and worries that day than attempting an 'orderly demo' of a mere building already about (and expected) to collapse anytime.
That's my two cents' worth, guys!
Cheers all!
RC.
.
Hi atmosphere, Chainsaw, wcelliot, everyone!
Re WTC7.
I thought that the 'transit' and other surveys indicated damage/instability such that it was expected to collapse at any time?
And that the ongoing diesel and widespread office fires were 'unpredictable'? Unlike 'ordinary' building fires WITHOUT such damage and ongoing dangerous conditions.
And that the ATTACKS and PANIC and loss of life ALREADY in WTC1&2 had put fire chiefs etc in the mindset of 'getting out' to avoid further loss of life.....and DAMN the buildings? Such that all concerned were merely pulled back to a safe distance to let it burn because no-one knew what ELSE may be happening to make it dangerous to do the 'usual' firefighting and cleanup until it was all over?
And in any case, the buildings were under OBSERVATION by MANY MEDIA reporters who would have noticed and EXTOLLED the 'courage' of ANYONE (let alone anyone 'loaded for demo'!) seen to enter WTC7 while everyone watched and waited for the inevitable to happen? The only 'unusual' thing seemed to be that WTC7 did NOT collapse as easily/quickly as EVERYONE expected. Such expectation by EVERYONE there, of IMMINENT COLLAPSE, would have mitigated against any decision to 'interfere', owing to the great potential for further loss of life. Can you just imagine the repercussions if thay HAD attempted to interfere with the fire and collapse progression, by attempting to demo the building, and the imminently expected collapse caught them as they were planting the necessaries?
What fire chief WHO ALREADY LOST SO MANY GOOD AND BRAVE PEOPLE IN THE DEVASTATING WTC FIRES/COLLAPSES would be STUPID and IRRESPONSIBLE enough to OK anything like that in ANOTHER HUGE BUILDING STILL ON FIRE AND MAKING CREAKING AND SNAPPING NOISES ON ALL SIDES....and which was already surveyed and judged BY FIREFIGHTING CHIEFS THEMSELVES to be in IMMINENT danger of collapse?
I'm sure they had greater sorrows and worries that day than attempting an 'orderly demo' of a mere building already about (and expected) to collapse anytime.
That's my two cents' worth, guys!
Cheers all!
RC.
.
QUOTE
I have never seen anyone dumb enough to enter a building that might explode at any time, with explosives!
The idea of risking lives in a building where an explosion can occur to set explosives to bring the building down is not a very smart or intelligent idea now is it?
Sorry experiments have shown me that only a fool would have entered those buildings, and I do not think that demolition experts are such fools.
The idea of risking lives in a building where an explosion can occur to set explosives to bring the building down is not a very smart or intelligent idea now is it?
Sorry experiments have shown me that only a fool would have entered those buildings, and I do not think that demolition experts are such fools.
I agree completely, and would add that nothing gets done in the real world without contracts in-place, especially regarding liabilities for injuries and potential loss of lives. While it's conceivable that one could find ninja-commando-fairies willing to risk their lives for marginal motives like trying to implode a burning building that's bound to collapse sooner or later, I've never heard of lawyers willing to draw up contracts limiting liabilities for that sort of thing in the time-frames available. If a lawyer rushes a contract, he risks losing his license to practice law.
While there may be heroes willing to risk their lives to plant explosives in a burning building, I doubt that there are lawyers willing to risk disbarment for participating in the same effort. (And remember, lawyers charge by the hour, so how much would they be paid for their efforts?) Without a contract, there would be no legal means of paying the ninja-commando-fairies, so that, alone, means it just didn't happen.
QUOTE (wcelliott+Nov 27 2007, 09:07 PM)
I agree completely, and would add that nothing gets done in the real world without contracts in-place, especially regarding liabilities for injuries and potential loss of lives. While it's conceivable that one could find ninja-commando-fairies willing to risk their lives for marginal motives like trying to implode a burning building that's bound to collapse sooner or later, I've never heard of lawyers willing to draw up contracts limiting liabilities for that sort of thing in the time-frames available. If a lawyer rushes a contract, he risks losing his license to practice law.
While there may be heroes willing to risk their lives to plant explosives in a burning building, I doubt that there are lawyers willing to risk disbarment for participating in the same effort. (And remember, lawyers charge by the hour, so how much would they be paid for their efforts?) Without a contract, there would be no legal means of paying the ninja-commando-fairies, so that, alone, means it just didn't happen.
Heroes do not go in burning buildings unless it is to save lives, not to blow up unoccupied buildings, that are collapsing in on themselves.
When the site is evacuated, and the pull comment is clearly pulling back the fire fighters trying to contain the fire from the outside of the building.
Saving lives that day was paramount not Building demolitions.
I tested both the Idea of preplanted charges and setting charges after the collapse of the towers, the explosive conditions present make it so stupid that it is not worth commenting on further.
An explosion of Carbons or diesel fuel vapor can set the charges off while your packing the charges inside the buildings in your own hands.
The emergency generators running, negate radio controls, detcord is a no no in that situation. Some one un noticed by all would have had to run wires to the detonator, or stayed behind and set off the charges.
Most people negate that there was an unknown amount of electromagnetic energy in that building, and that radio detonators can be triggered by that alone.
The situation is one that I know I would only undertake if It were to save lives not property, property can be replaced your life can not only insane and crazy people risk their life for Property.
QUOTE
The situation is one that I know I would only undertake if It were to save lives not property, property can be replaced your life can not only insane and crazy people risk their life for Property.
I think we're in complete agreement that the whole notion is ludicrous, I was merely pointing out that while there may be insane/crazy people willing to risk their lives for a pointless venture (collapsing a building already in the process of collapsing on its own), that the concept also presumes that people could find lawyers willing to risk disbarment to draw up a hastily-conceived contract to implement an ill-conceived notion, making it doubly improbable.
Heroic explosives experts, maybe.
Heroic lawyers, never in a million years.
Ok, I can finally obtain solutions with a substantial resistive force term for concrete comminution. The change is to assume that all the concrete in the crushed mass is subject to continued re-comminution due to blows, not only from above at the crushing front, but from below as well. This term then becomes
F4*(Z-Z0)*S*S
where F4 is the parameter, (Z-Z0) is the mass of the crushed block and S is the speed of the crushing front. To compare with the term of the resistive force due to sheer consumption of some of the kinetic energy,
F3*Z*S
where F3 is the parameter,
F4 = 0.3253
F3 = 0.7903
although other runs, with slightly different assumptions, give other values which result in curves with almost as little variance. In every case, F4 < F3.
Also of some interest is a different form for the stretch (squash):
s(Z) = (S0-S2)*(Z0/Z)^p + S2
where S0, p and S2 are parameters to be adjusted for best fit to the data. Since this form can easily be incorporated in the computer models used by others, I give the parameter values obtained using the B&V crush-down equation:
S0 = 0.5255
p = 2.8817
S2 = 0.2776
Now, in some sense, S0 is completely reasonable, although S2 seems too large given that at the end of 3.82 seconds the crushing front is moving at about 25 m/s. But the value of p, about 3, is a complete surprise! When working out some physics of this situation, using compressible fluid flow as a guide, I had thought that about 2 would be the exponent. Well, I suppose 2.8817 is 'about 2', but I am at a loss as to why this exponent is about 3 instead.
F4*(Z-Z0)*S*S
where F4 is the parameter, (Z-Z0) is the mass of the crushed block and S is the speed of the crushing front. To compare with the term of the resistive force due to sheer consumption of some of the kinetic energy,
F3*Z*S
where F3 is the parameter,
F4 = 0.3253
F3 = 0.7903
although other runs, with slightly different assumptions, give other values which result in curves with almost as little variance. In every case, F4 < F3.
Also of some interest is a different form for the stretch (squash):
s(Z) = (S0-S2)*(Z0/Z)^p + S2
where S0, p and S2 are parameters to be adjusted for best fit to the data. Since this form can easily be incorporated in the computer models used by others, I give the parameter values obtained using the B&V crush-down equation:
S0 = 0.5255
p = 2.8817
S2 = 0.2776
Now, in some sense, S0 is completely reasonable, although S2 seems too large given that at the end of 3.82 seconds the crushing front is moving at about 25 m/s. But the value of p, about 3, is a complete surprise! When working out some physics of this situation, using compressible fluid flow as a guide, I had thought that about 2 would be the exponent. Well, I suppose 2.8817 is 'about 2', but I am at a loss as to why this exponent is about 3 instead.
QUOTE (einsteen+Nov 27 2007, 07:54 PM)
Edited:
I think that you mean that when the velocity is near zero, say 0.1 m/s and E1 is fitted in a way that it stops at the next story with v=0 then the time is h/0.05, I think that is true, but if the collapse is rapid in the beginning then that will not happen I think
I ran my algebraic crush-up model for WTC7 where the mass per story is the same for all stories and equal to what Greening was using per story (510E6 kg / 110). E1 is considered the same for all stories.
For E1=1.85 GJ, the collapse duration is 7.2 s. The crush-up is just barely arrested at the top of the building. E1/m at the ground level is 8.5 J/kg.
For E1=3 GJ, the duration is 8.3 s. The collapse is arrested at the 44th story. Even though the collapse didn't go to completion, the duration is longer than 7.2 s. E1/m at the ground level is 13.8 J/kg.
For E1=1 GJ, the collapse goes to completion and the duration is 6.6 s. E1/m at the ground level is 4.6 J/kg.
The continuous model using diffeq gives similar but slightly longer durations. I can post some of the displacement and velocity curves for the diffeq solution if anyone is interested.
QUOTE (atmosphere+Nov 27 2007, 11:31 AM)
People entered burning buildings before that day ,buildings with larger fires .
a number of first responders report explosions
you can't compare a normal controlled demolition with the one of WTC 7 at 9/11.
For bringing down building 7 they didn't need to do all the work to prevent breaking windows of other buildings , they didn't need to blow everything into small pieces . Normally they often do this to be able to load the debris directly on trucks. These things normally take a lot of preparing time
In the polluted environment at ground zero that day all they had to do is place explosives on the central columns and or cut some in -V- shape. WTC 7 had large wide span areas and therefore relatively few columns . All of this makes a fast demolition with explosives possible .
If you bring down a building like that with explosives you end up with the same scenario as seen on 9/11
I know of NO times that people who worked for a CD company EVER entered a BURNING BUILDING.
The idea that they would is something YOU apparently believe, but its NOT supported by ANY past behavior.
You also dodge WHY these people would keep this secret and offer NO RATIONAL REASON why the people who supposedly did this would not want it known.
Sure, SOME of the prep time could be eliminated in a pinch, but you act like these columns are READILY accessible. They aren't. These buildings typically hide their internal structure. I suspect it would be VERY difficult to identify these KEY columns in a DARK/BURNING building, then do the work to expose the framework so you could set the explosives. It would be even more difficult, in this environment, to make them go off in the exact time sequence you want, to make the building fall the way you want. Which is a MAJOR issue. A building like WTC 7 is almost guaranteed to fall pretty much straight down IN THE ABSENCE of major asymmetrical damage, something that could EASILY happen if only some of the explosives went off. Any attempt to BLOW the building would probably INCREASE the chances that one would cause more collateral damage.
Finally look at the PDF I linked to.
http://www.fema.gov/pdf/library/fema403_ch5.pdf
See figure 5-2
There are 83 columns per floor and they are spaced in 10' increments E to W and 28 ft N to S and Core, so NO, its not like there are just a few columns.
Arthur
a number of first responders report explosions
you can't compare a normal controlled demolition with the one of WTC 7 at 9/11.
For bringing down building 7 they didn't need to do all the work to prevent breaking windows of other buildings , they didn't need to blow everything into small pieces . Normally they often do this to be able to load the debris directly on trucks. These things normally take a lot of preparing time
In the polluted environment at ground zero that day all they had to do is place explosives on the central columns and or cut some in -V- shape. WTC 7 had large wide span areas and therefore relatively few columns . All of this makes a fast demolition with explosives possible .
If you bring down a building like that with explosives you end up with the same scenario as seen on 9/11
I know of NO times that people who worked for a CD company EVER entered a BURNING BUILDING.
The idea that they would is something YOU apparently believe, but its NOT supported by ANY past behavior.
You also dodge WHY these people would keep this secret and offer NO RATIONAL REASON why the people who supposedly did this would not want it known.
Sure, SOME of the prep time could be eliminated in a pinch, but you act like these columns are READILY accessible. They aren't. These buildings typically hide their internal structure. I suspect it would be VERY difficult to identify these KEY columns in a DARK/BURNING building, then do the work to expose the framework so you could set the explosives. It would be even more difficult, in this environment, to make them go off in the exact time sequence you want, to make the building fall the way you want. Which is a MAJOR issue. A building like WTC 7 is almost guaranteed to fall pretty much straight down IN THE ABSENCE of major asymmetrical damage, something that could EASILY happen if only some of the explosives went off. Any attempt to BLOW the building would probably INCREASE the chances that one would cause more collateral damage.
Finally look at the PDF I linked to.
http://www.fema.gov/pdf/library/fema403_ch5.pdf
See figure 5-2
There are 83 columns per floor and they are spaced in 10' increments E to W and 28 ft N to S and Core, so NO, its not like there are just a few columns.
Arthur
Here is an example of calculating the crush-up duration for WTC7 using the discrete and the continuous model.
Let the mass per story be the same for all stories and equal to 510E6 kg / 110.
Using my discrete algebraic model (discrete meaning that this program does a calculation at each of the 47 stories):
Let E1 be 1.3 GJ at the ground level and decrease linearly to 0 GJ at the top of the building. This means that E1/mh is the same throughout the building. The discrete algebraic model gives a collapse duration of
t = 6.6 s.
E1/mh in this case is 1.3 GJ / ([510E6 kg*47/110]*3.78 m) = 1.58 m/s^2
Compare that with the solution to the diffeq of a continuous model for the case of E1/mh being a constant (that I derived in a previous post on p538):
t = sqrt(2*H/[9.81 - E1/mh])
t = sqrt(2*47*3.78/[9.81 - 1.58])
t = 6.6 s
The two solutions agree.
Note also that the collapse duration for WTC7 is 6.6 s for the case of E1=1GJ for all stories (and where the mass per story is 510E6 kg / 110).
Let the mass per story be the same for all stories and equal to 510E6 kg / 110.
Using my discrete algebraic model (discrete meaning that this program does a calculation at each of the 47 stories):
Let E1 be 1.3 GJ at the ground level and decrease linearly to 0 GJ at the top of the building. This means that E1/mh is the same throughout the building. The discrete algebraic model gives a collapse duration of
t = 6.6 s.
E1/mh in this case is 1.3 GJ / ([510E6 kg*47/110]*3.78 m) = 1.58 m/s^2
Compare that with the solution to the diffeq of a continuous model for the case of E1/mh being a constant (that I derived in a previous post on p538):
t = sqrt(2*H/[9.81 - E1/mh])
t = sqrt(2*47*3.78/[9.81 - 1.58])
t = 6.6 s
The two solutions agree.
Note also that the collapse duration for WTC7 is 6.6 s for the case of E1=1GJ for all stories (and where the mass per story is 510E6 kg / 110).
QUOTE (shagster+Nov 28 2007, 02:58 AM)
Here is an example of calculating the crush-up duration for WTC7 using the discrete and the continuous model.
Let the mass per story be the same for all stories and equal to 510E6 kg / 110.
Using my discrete algebraic model (discrete meaning that this program does a calculation at each of the 47 stories):
Let E1 be 1.3 GJ at the ground level and decrease linearly to 0 GJ at the top of the building. This means that E1/mh is the same throughout the building. The discrete algebraic model gives a collapse duration of
t = 6.6 s.
E1/mh in this case is 1.3 GJ / ([510E6 kg*47/110]*3.78 m) = 1.58 m/s^2
Compare that with the solution to the diffeq of a continuous model for the case of E1/mh being a constant (that I derived in a previous post on p538):
t = sqrt(2*H/[9.81 - E1/mh])
t = sqrt(2*47*3.78/[9.81 - 1.58])
t = 6.6 s
The two solutions agree.
Note also that the collapse duration for WTC7 is 6.6 s for the case of E1=1GJ for all stories (and where the mass per story is 510E6 kg / 110).
in other words, if you bomb the bottom out of the building, it goes into freefall.
Let the mass per story be the same for all stories and equal to 510E6 kg / 110.
Using my discrete algebraic model (discrete meaning that this program does a calculation at each of the 47 stories):
Let E1 be 1.3 GJ at the ground level and decrease linearly to 0 GJ at the top of the building. This means that E1/mh is the same throughout the building. The discrete algebraic model gives a collapse duration of
t = 6.6 s.
E1/mh in this case is 1.3 GJ / ([510E6 kg*47/110]*3.78 m) = 1.58 m/s^2
Compare that with the solution to the diffeq of a continuous model for the case of E1/mh being a constant (that I derived in a previous post on p538):
t = sqrt(2*H/[9.81 - E1/mh])
t = sqrt(2*47*3.78/[9.81 - 1.58])
t = 6.6 s
The two solutions agree.
Note also that the collapse duration for WTC7 is 6.6 s for the case of E1=1GJ for all stories (and where the mass per story is 510E6 kg / 110).
in other words, if you bomb the bottom out of the building, it goes into freefall.
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