Why all the worldwide turmoil? (9/11 thread)

[hot enough]

7 minutes ago, dre said:

I think the building were just built by shitty tradesman, working for shitty contractors, using shitty steel, with shitty engineering.

From popular mechanics...

In other words their crappy ass buildings fell down because they were not built properly, and a lot of people died because of the developers being cheap.

Is that you paraphrasing Popular Mechanics or is it a quote from them?

[betsy]

8 minutes ago, hot enough said:

Could you direct me to those?

I've got not time.  You find it.  It's on this thread.  It's by Popular mechanics.  You actually mentioned it in passing.

 

Anyway, that last article I gave you busted your whole theory!

Edited March 2, 2017 by betsy

[hot enough]

5 minutes ago, betsy said:

I've got not time.  You find it.  It's on this thread.  It's by Popular mechanics.  You actually mentioned it in passing.

You just gave a link to the whole mess of Popular Mechanics drivel. I want you to quote the pertinent section, like I did in my first post. You have no time to do your own homework. That's lazy and crazy. 

Edited March 2, 2017 by hot enough
clearer explanation

[dre]

Sorry I misspoke those are from JOM (Journal of Metals and Materials). And they are quotes.

 

http://www.tms.org/pubs/journals/JOM/aboutJOM.aspx

[?Impact]

There is a huge source of heat that so far seem to have been discounted. As the tower collapsed, it would meet some resistance from the next floor down and that would momentarily slow down the descent until that floor and supporting columns give way and the combined mass continues its descent. The energy must go somewhere according to my friend Newton, and that kinetic energy is converted to thermal energy. You can experience this by clapping your hands together rapidly, and they heat up as kinetic energy is converted to thermal energy. A 110 story building, weighing in at a half million tons, would have a huge amount of kinetic energy. How much got converted to thermal energy?

[hot enough]

5 minutes ago, dre said:

Sorry I misspoke those are from JOM (Journal of Metals and Materials). And they are quotes.

 

http://www.tms.org/pubs/journals/JOM/aboutJOM.aspx

Nothing on that page that you have linked to, dre.

[hot enough]

5 minutes ago, ?Impact said:

There is a huge source of heat that so far seem to have been discounted. As the tower collapsed, it would meet some resistance from the next floor down and that would momentarily slow down the descent until that floor and supporting columns give way and the combined mass continues its descent.

That's the point, no JOLTS, no slowing. It only accelerated. 

[dre]

2 minutes ago, hot enough said:

Nothing on that page that you have linked to, dre.

LOL Crap, sorry!

http://www.tms.org/pubs/journals/jom/0112/eagar/eagar-0112.html

[?Impact]

5 minutes ago, hot enough said:

That's the point, no JOLTS, no slowing. It only accelerated. 

Evidence? According to the video and seismic evidence there was some slowing. You even acknowledged that before for the twin towers. The question I am posing is if we can quantify it, and yes I know there is a lot of variability, can we calculate the thermal energy generated. Some of that thermal energy would be dispersed in the air as it fell, but that would be over a very brief few seconds. I expect most of that thermal energy would end up in the rubble pile, and the lower you are in that pile the higher it would be.

[dre]

1 minute ago, hot enough said:

That's the point, no JOLTS, no slowing. It only accelerated. 

You would not expect them.

The structure below was engineered to hold the weight of the floors above at rest. However when an object falls its potential gravitational energy is converted to kinetic energy.

For example... 1 kg  of matter at rest puts marginal force on the structure below it. Effectively maybe .01 joules. However if that object falls from 5 meters (roughly the high of each floor in the WTC) it falls for 1.1 seconds building up kinetic energy the entire time. By the time impacts the floor below it, it will exert 49 joules of force on the structure below it.

In other words that 5 meter fall results in about 500 times as much force as the structure below is designed to withstand. Its like dropping a brick on a frame made of match sticks. You would not expect to see any visible resistance to the falling object at all. From a physics standpoint you would expect to see exactly what you did see.

Heres some math to play with...

Quote

As an object falls from rest, its gravitational potential energy is converted to kinetic energy. Consider a mass m which is falling vertically under the influence of gravity.

Object is falling from rest, therefore initial kinetic energy is zero. Once the object hit on the ground, height is zero, therefore no potential energy at ground level.

Initial PE = Final KE
 

Impact velocity just before the impact is 

From work-energy principle, change in the kinetic energy of an object is equal to the net work done on the object.


For a straight-line collision, the total work done is equal to the average force of impact times the distance traveled during the impact.
Average impact force x Distance traveled = Change in kinetic energy

Total work done = Kinetic energy just before object hit the ground

Impact force

And here's a splat calculator you can use if you don't want to do the math yourself.

[betsy]

24 minutes ago, hot enough said:

You just gave a link to the whole mess of Popular Mechanics drivel. I want you to quote the pertinent section, like I did in my first post. You have no time to do your own homework. That's lazy and crazy. 

I did quote it!

[dre]

6 minutes ago, ?Impact said:

Evidence? According to the video and seismic evidence there was some slowing. You even acknowledged that before for the twin towers. The question I am posing is if we can quantify it, and yes I know there is a lot of variability, can we calculate the thermal energy generated. Some of that thermal energy would be dispersed in the air as it fell, but that would be over a very brief few seconds. I expect most of that thermal energy would end up in the rubble pile, and the lower you are in that pile the higher it would be.

No matter what there was SOME slowing. The laws of physics dictate that. But based on the kinetic energy that would have been built up during a 1.1 second 5 meter fall, it would not even be close to enough for the human eye to notice. 

[hot enough]

4 minutes ago, ?Impact said:

Impact: Evidence? According to the video and seismic evidence there was some slowing. You even acknowledged that before for the twin towers.

hot enought: Did I? I believe I have maintained all along that there was constant acceleration. Constant acceleration is something which is impossible in a gravity collapse. It points to the underlying supporting structure being removed allowing all the energy to be converted to kinetic energy. 

Can you source the "According to" stuff?

Impact: The question I am posing is if we can quantify it, and yes I know there is a lot of variability, can we calculate the thermal energy generated. Some of that thermal energy would be dispersed in the air as it fell, but that would be over a very brief few seconds. I expect most of that thermal energy would end up in the rubble pile, and the lower you are in that pile the higher it would be.

hot enough: Are you going here?  ----> Thermal energy can account for the vaporized steel, melted Mo, vaporized lead, ... .

 

[betsy]

25 minutes ago, hot enough said:

You just gave a link to the whole mess of Popular Mechanics drivel. I want you to quote the pertinent section, like I did in my first post. You have no time to do your own homework. That's lazy and crazy. 

Seems like you're trying to pull a fast one.   Saying it's drivel, isn't a rebuttal you know.  You gotta explain why you say it's drivel.

You didn't even read it,  most likely.

[hot enough]

5 minutes ago, betsy said:

Seems like you're trying to pull a fast one.   Saying it's drivel, isn't a rebuttal you know.  You gotta explain why you say it's drivel.

You didn't even read it,  most likely.

If it is such hot stuff, Betsy, post it and it will devastate. 

[betsy]

12 minutes ago, hot enough said:

If it is such hot stuff, Betsy, post it and it will devastate. 

 I already gave it - directly quoted you in response -  and now you're saying you ignored it.  You find it. 

 

Actually, why don't you refute the last ones I gave?   I wonder why don't you deal with those now?  Before you lost them too?

Edited March 2, 2017 by betsy

[betsy]

17 minutes ago, hot enough said:

If it is such hot stuff, Betsy, post it and it will devastate. 

 

The last two ones are even hotter.  Deal with those last two posts I gave you - you don't have to scroll up far.  

 

Here....there's two of them on page 12.

 

I'll have to apply pressure on you to refute.  It looks like you're playing some cat and mouse game here - asking for the Popular Mechanics you've deliberately ignored, and now you're going to let these two last rebuttals I gave you get buried too - and then you'll be asking, "where are they?  Post them betsy and I'll refute them! "

 

I won't be entertaining anything from you until you've refuted them!

 

Edited March 2, 2017 by betsy

[hot enough]

23 minutes ago, betsy said:

 I already gave it - directly quoted you in response -  and now you're saying you ignored it.  You find it. 

 

Actually, why don't you refute the last ones I gave?   I wonder why don't you deal with those now?  Before you lost them too?

Regarding "it". "it" wasn't an "it". It was the complete volume of Popular Mechanics. If there was an "it" that related to my offering, you should present your "it". I wouldn't just give you a link to a complete digest of material. 

The last one wasn't a "ones". Do you even read your stuff? It made some excellent points and I will read it again and digest what is contained therein.

[betsy]

7 minutes ago, hot enough said:

Regarding "it". "it" wasn't an "it". It was the complete volume of Popular Mechanics. If there was an "it" that related to my offering, you should present your "it". I wouldn't just give you a link to a complete digest of material. 

The last one wasn't a "ones". Do you even read your stuff? It made some excellent points and I will read it again and digest what is contained therein.

For someone who critics a lot, you seem to be saying hardly anything about the real issue?

[?Impact]

13 minutes ago, dre said:

Heres some math to play with...

Yes, that is good math for determining the kinetic energy but what I am still confused is how do we calculate the thermal energy. I guess if we can figure out how much slowing occurred at each floor, we can basically reverse the calculation to determine the loss of kinetic energy and that would become thermal energy also expressed in joules (raise a gram of water by about a quarter of a degree centigrade). I'm wondering if there is a back of napkin calculation we can do based on about 35% slowing overall (ie. a few seconds on top of free fall speed). It sounds like a lot of thermal energy to me.

13 minutes ago, dre said:

No matter what there was SOME slowing. The laws of physics dictate that. But based on the kinetic energy that would have been built up during a 1.1 second 5 meter fall, it would not even be close to enough for the human eye to notice. 

Agreed the slowing for a single floor would not be close enough for the eye to notice. We do know that the eye, and especially the camera, did catch the slowing across several floors by the difference in the descent rate of the tower compared to the parts that broke off and fell outside.

[hot enough]

1 hour ago, betsy said:

 

 

Here's an additional  rebuttal - knocking down everything about your silly theory.

 

https://en.wikipedia.org/wiki/World_Trade_Center_controlled_demolition_conspiracy_theories

 

1 hour ago, betsy said:

Controlled demolition of a building to code requires weeks of preparation, including laying large quantities of explosive and cutting through beams, which would have rendered the building highly dangerous and which would have to be done without attracting the attention of the thousands of people who worked in the building.^[7][55] Controlled demolition is traditionally done from the bottom of buildings rather than the top, although there are exceptions depending on structural design. There is little dispute that the collapse started high up at the point where the aircraft struck. Furthermore, any explosives would have to withstand the impact of the airliners.^[7]

 

In 2002, the National Institute of Standards and Technology (NIST) began a general investigation into the collapse of the World Trade Center but soon made a decision to focus first on the collapse of the Twin Towers.

 

The report concluded that the building's collapse was due to the effects of the fires which burned for almost seven hours.

 

The fatal blow to the building came when the 13th floor collapsed, weakening a critical steel support column that led to catastrophic failure, and extreme heat caused some steel beams to lose strength, causing further failures throughout the buildings until the entire structure succumbed. Also cited as a factor was the collapse of the nearby towers, which broke the city water main, leaving the sprinkler system in the bottom half of the building without water.

NIST considered the possibility that 7 WTC was brought down with explosives and concluded that a blast event did not occur, that the "use of thermite [...] to sever columns in 7 WTC on 9/11/01 was unlikely".^[81]

 

The structural engineering community rejects the controlled-demolition conspiracy theory. Its consensus is that the collapse of the World Trade Center buildings was a fire-induced, gravity-driven collapse, an explanation that does not involve the use of explosives.  

 

Thomas Eagar, a professor of materials science and engineering at the Massachusetts Institute of Technology, also dismissed the controlled-demolition conspiracy theory.^[4] Eagar remarked, "These people (in the 9/11 truth movement) use the 'reverse scientific method.' They determine what happened, throw out all the data that doesn't fit their conclusion, and then hail their findings as the only possible conclusion.

I quoted the whole thing, Betsy, to illustrate that you don't seem to know much about the topic as a whole. I know that it is exceedingly complex but your "rebuttal" is a mishmash of incongruent ideas. You start out quoting about the twin towers and immediately morph into WTC7. 

How are a few wildly ranging factoids any help at all to the discussion. Now you can see [I hope] why I didn't read PM's wildly ranging factoids.

[hot enough]

1 hour ago, dre said:

The structure below was engineered to hold the weight of the floors above at rest. However when an object falls its potential gravitational energy is converted to kinetic energy.

That isn't true, dre. EDITED: I should have said "That isn't completely true, dre." 

Quote

Like All Skyscrapers, the Twin Towers Were Over-Engineered

One aspect of engineering that is not widely understood is that structures are over-engineered as a matter of standard practice. ⁷   Steel structures like bridges and buildings are typically designed to withstand five times anticipated static loads and 3 times anticipated dynamic loads. The anticipated loads are the largest ones expected during the life of the structure, like the worst hurricane or earthquake occurring while the floors are packed with standing-room-only crowds. Given that September 11th was not a windy day, and that there were not throngs of people in the upper floors, the critical load ratio was probably well over 10, meaning that more than nine-tenths of the columns at the same level would have to fail before the weight of the top could have overcome the support capacity of the remaining columns.

There is evidence that the Twin Towers were designed with an even greater measure of reserve strength than typical large buildings. According to the 1964 white paper cited above, a Tower would still be able to withstand a 100-mile-per-hour wind after all the perimeter columns on one face and some of the columns on each adjacent face had been cut. ⁸   Also, John Skilling is cited by the Engineering News Record for the claim that "live loads on these [perimeter] columns can be increased more than 2000% before failure occurs." ⁹  

http://911research.wtc7.net/wtc/analysis/design.html

 

Edited March 2, 2017 by hot enough
clearer explanation

[betsy]

19 minutes ago, hot enough said:

 

I quoted the whole thing, Betsy, to illustrate that you don't seem to know much about the topic as a whole. I know that it is exceedingly complex but your "rebuttal" is a mishmash of incongruent ideas. You start out quoting about the twin towers and immediately morph into WTC7.

 

The article is too long.  I can only post so much, so I had to edit.  You're supposed to go to the link and read it as a whole!

 

I did also quote this:

 

Quote

The structural engineering community rejects the controlled-demolition conspiracy theory. Its consensus is that the collapse of the World Trade Center buildings was a fire-induced, gravity-driven collapse, an explanation that does not involve the use of explosives.

 

 

Edited March 2, 2017 by betsy

[hot enough]

4 minutes ago, betsy said:

 

The article is too long.  I can only post so much, so I had to edit.  You're supposed to go to the link and read it as a whole!

 

 

 

Precisely, too long, and you don't seem to know how to edit or choose material appropriate to the discussion at hand. I would still be interested in the section of PMs that relates to the initial points, and then the sources that discussed the molten metals. 

[dre]

45 minutes ago, ?Impact said:

Yes, that is good math for determining the kinetic energy but what I am still confused is how do we calculate the thermal energy. I guess if we can figure out how much slowing occurred at each floor, we can basically reverse the calculation to determine the loss of kinetic energy and that would become thermal energy also expressed in joules (raise a gram of water by about a quarter of a degree centigrade). I'm wondering if there is a back of napkin calculation we can do based on about 35% slowing overall (ie. a few seconds on top of free fall speed). It sounds like a lot of thermal energy to me.

Agreed the slowing for a single floor would not be close enough for the eye to notice. We do know that the eye, and especially the camera, did catch the slowing across several floors by the difference in the descent rate of the tower compared to the parts that broke off and fell outside.

I dont think thermal energy is at question here. Conspiracy theorists point out that burning jet fuel should not have burned hot enough to melt the steel columns... under normal circumstances it will only burn at about 800 degrees. However, the NIST did test burns and found that burning computers and office furniture could easy causes temperatures to reach 1100 degrees. While that isn't enough to MELT steal it is enough to distort and weaken it, and the buildings were already poorly engineered and under-built. The "molten metal" that is visible in the photos and videos is mostly the aluminum from the chassis of the aircraft itself which would melt at a much lower 630 degrees.