WTC PHYSICS (Part 1 of 2)

[marcoddy]

Why i this out of date?

[femr2]

The mathematical/physics model which the calculations and simulation is driven from has been updated, improved and extended. Many refinements have been included, such as the use of specific floor heights, specific floor by floor live load masses etc.

[marcoddy]

cool... so which is the new one?

[femr2]

The linked playlist all use the updated model. Just this and part 2 are out of date.

femr2. ucoz. com

The calcs can be downloaded from there.

[proudfootz]

Yes, I think Gordon Ross did a good job of exposing the defincincies of Greening's calculations.

Thanks for this simulation which completes the job.

[taledarkside]

How can you say your using physics when your using inaccurate numbers? The time and method for calculating the time the buildings fell is incorrect. And your video is pointless in that regard.

Create a video of getting real collapse time of the building. Havn't seen one video to give accurate collapse time or calculation.

[femr2]

We can go into a great deal of detail on the subjects raised by your question, but to begin:

1) What numbers are you suggesting are inaccurate ?

2) What "method for calculating the time the buildings fell is incorrect" are you referring to ?

I will expect precise responses to these questions.

The purpose of the model is to teach you the effect of various parameters on the collaspe time. I think you may be misunderstanding the times shown in each scenarion. I can explain if you are.

[taledarkside]

you have to prove the buildings fell faster then free fall speed. Why don't you prove that. 

1. the buildings never got 100% destroyed.

2. the variables put into the free fall equation is inaccurate

So stating the buildings fell at free fall speed and or faster is false. Isn't that what your video states right in the beginning. You should prove that first before going into a simulation.

Ill be back on later

[femr2]

"you have to prove the buildings fell faster then free fall speed."

No I don't, and that would be impossible without a specific implosive force.

(There's no need to pad out your lack of thought with chr(13))

"1. the buildings never got 100% destroyed."

I never said they did, although I assume you are referring to momentary core remnants. I'll explain to you in detail if required.

"2. the variables put into the free fall equation is inaccurate"

You'll need to be a lot more precise. What value?

[taledarkside]

height value. if you drop a ball at 300 feet high vs 250 feet high. Your going to get a different value of free fall time.

Now you going to state that something fell from a 300 ft value and say it fell too fast. When it really fell from a 250ft value, your going to assume the ball was accelerated.

[femr2]

You values are totally random. I can assure you that all values used are highly accurate, using absolute floor heights accurate to the inch.

Do you understand conservation of momentum ?

If not, you are not going to understand the information presented.

The time increase is due to the need to accelerate the impacted mass of each successive floor. This requires energy and results in a change in vertical velocity.

Do you understand ?

[taledarkside]

and do you understand Force= Mass x acceleration?

and i can post up the formula for stress loading.

you said the building fell at what 9.2 seconds. you said that made the building fall faster then free fall. prove to me that the building fell to fast. Give me a height value so i can figure it out myself.

[femr2]

Can you read ? What is said in the video is this:

"

WTC 1 came down in a time near to 'free fall'

Supporters of the Official Lies deny this and argue that the free-fall timing of an object from the top of the tower is ~9.2s.

9.2s is actually the time an object in a vacuum will take to fall from the top of the tower.

Free-fall for WTC 1 is the minimum time it can collapse in if ALL RESISTANCE is ignored.

"Conservation of Momentum" results in a MINIMUM collapse time of over 11 seconds.

"

[taledarkside]

But the tower didn't fall from the top of the tower.

now did it

[femr2]

"But the tower didn't fall from the top of the tower."

Indeed, which is why my calculations use a very conservative failure floor of floor 96.

The visual representation clearly shows this.

Are you on the wind-up, or are you really having this much difficulty in seeing the data being shown ?

The tower visualisations clearly do not fall 'from the top of the tower'.

[taledarkside]

And what floor did the plane hit? Because that is where the building started to fall for one of the buildings.

Or give me the distance of fall of the building.  because it will not equal a free fall height.

[femr2]

"give me the distance of fall of the building"

Firstly, adjust your tone now, or this conversation is over. Last warning.

356.6m

[femr2]

Now then...Do you understand the effect of "Conservation of Momentum" ?

The calculation is far beyond a simple F=Ma formula, and requires momentum transfer calculation on a per floor impact basis.

As soon as my site is back up, I'll point you to a spreadsheet with all the calculations involved.

Again, be nice. Not to sound superior, but I appear to know an awful lot more about this subject than you do, but I am happy to help you if you can be pleasant.

[taledarkside]

really. you went to engineering school too?

you can do a "per floor basis" with the force formula also.  because the mass changes on each floor of the collapse.

[femr2]

If you were qualified in engineering, you would not be querying the use of conservation of momentum.

You would not be incapable of reading.

You would not have trouble seeing that my calculations do not implement a 'from the top of the tower'.

You would not be wasting my time.

[taledarkside]

and whats your formula for conservation of momentum?

because the one I was taught is the same as force.

Adn all I see as your calculations in the video is an automation of numbers. there is no formulas for each section.

[femr2]

I just told you, as soon as my site is back up, I'll point you to a spreadsheet with the full calculations.

[taledarkside]

so you cant give me the formula for conservation of momentum?

so your just another nut job with no credibility.

i can give you the Force=M*A formula.

[femr2]

"so your just another nut job with no credibility."

You were warned. Goodbye.

[femr2]

"stating the buildings fell at free fall speed and or faster is false. Isn't that what your video states right in the beginning."

No. You clearly have trouble with comprehension. I state that freefall timings often cited are wrong, as they don;t take conservation of momentum into account. The ~11s timing stated is a zero resistance free-fall timing which results through the need to accelerate impacted mass. It is not a suggestion of the 'actual' descent time.

[femr2]

"You should prove that first before going into a simulation."

You obviously have no idea how to approach simulation. The method you are suggesting is specifically known as 'dry labbing', and is a very poor approach. As you are now also aware, your prior statement was based on your misunderstanding and bad comprehension skills.

I am happy to continue discussion with you, but I suggest you adopt a VERY much more polite and less accusing tone.

[dukemalibu]

We appreciate your work, thank you.

[femr2]

I see you are asking about steel and concrete masses on JREF. If you download the spreadsheet on my site, there are pretty good mass calculations within it. The sources for the data are included. Mostly NIST, though they don't specify the specific mass itself, but from the data they 'do' supply, it can be calculated.

I note that Ryan is still 'ignoring' the model, even though he stated it "is clearly the best entry in response to my "Hardfire Modeling Challenge."". Very odd.

femr2. ucoz. com

[psikeyhackr]

What I find peculiar is people tolerating inadequate information from the NIST. Gregory Urich's spreadsheet is the most detailed I have seen but he admits that the perimeter column information is interpolated. The NIST has not supplied the number and weights of each of the 12 different types of perimeter columns. How much concrete was on the 6 basement levels?

How could they not supply info that simple in 3 years with $20,000,000? Why does everyone put up with this BS?

[femr2]

You are quite correct. It is a disgrace. I also want the mass and strength data for each of the differing 12 floor construction types, as that will make an appreciable difference in modelled 'collapse' times...

Urich's spreadsheet ? I've seen the paper, but not the spreadsheet. Do you have a link ?

[psikeyhackr]

If you do a Google search on:

+"column steel" +"floor inside core"

it should be the first thing that turns up. It is an XLS spreadsheet.

[femr2]

Thanks. Handy. May add it to the model. If it differs significantly I'll make it an optional 'switch'.

It's in a PDF, but I can grab the data out of there okay.

[accersitusmaximus]

There is never enough evidence for a skeptic, nor enough Scripture for the scholar. However, a steel framed building does not suddenly collapse at free fall under constant acceleration unless no resistance is offered (according to NIST themselves).

What can cut 80 steel columns on 47 floors within seconds? Fire?

200000 tons of structural steel. No resistance. Think about it.

[xdyingfetusx69]

yep and debunkers and ppl on youtube actually believe that shit, err they call them debunkers then they start hating on truthers its sad... i bet most of them are shills anyway

[onesliceshort]

Wow I didnt noticed all those floors in one perfect block sitting on top of the rubble at ground zero...the other thing is that wtc2 was damaged more to one side and should have fallen that way....if you go by the weird physics of the day...you cant have it both ways.

Mark Roberts quote I noticed the other day

¨The 9/11 Truth movement has turned to dust and blown away¨ Arrogant asshole doesn´t realize that comments like that spurs people on. They never learn.

[femr2]

From your comment, I'm not sure of it's purpose.

I can explain any element of the model utilised in the physics simulation if you are querying the presence of the cap at the end of the simulations.

There was no weird physics on the day.

The only 'weird' thing is the Official Fairytale explanation. Accepting the Official Theory requires you to believe that the laws of physics can be broken. They cannot. The Official Theory is a lie.

[CHEWDwivTHEinCrowd]

very informative thanks

[swingdangler]

Not only is Greening wrong, his model doesn't match reality. The top section of WTC 1 didn't remain as one rigid block crushing down the bottom part. It was being destroyed prior to that. The same observation can be seen in WTC 2 even better. The top part did not crush down the bottom part, it disintegrated early on!

These self-styled debunkers can't produce anything that matches the physical reality captures on film. Now you know why NIST didn't model the global collapse, only initiation.

[femr2]

swing...I agree in full, though of course certain numerical aspects of the approach are very valid in order to understand the basic mechanics and energetics which occur. The WTC Collapse simulator can use the same 'crush down' model, though of course with much more accurate source data, and numerous additional factors included. These clips all utilise the crush down model.

[femr2]

The reason for incorporating the crush down model in the WTC Collapse Simulator is that it provides the maximum energy available for continued collapse.

This leans heavily in favour of the Official Fairytale, and emphasises that even using the simplified model favouring the Official Theory, global collapse driven solely by gravitational potential energy is NOT what occurred on 9/11.

The only way to explain the rapid descent and calculable energy expenditure is through controlled demolition.

[ErwinMaster]

Hmm... Im nto sure, Busg is an asshole. but I don't think he or whatever did this. I guess Putting the fault to mulim's is a bit cliché.. but This doesn't makes any sense eather. Wheer does all that matter go.. when it goes grownwards? it is bourded inwards or outwards, if it bourders outwards, it would go faster for pulling iron bars in the top structure...

But ... well I guess you're right lol

=D

[femr2]

erwin...I'm not focussed on who was to blame. I focus on showing that WTC 1, 2 & 7 were demolished, and hope I provide good evidence to back up the position.

"Wheer does all that matter go"

The debris field stretched for 600ft in all directions, spreading mass from each tower over a wide area.

"if it bourders outwards, it would go faster for pulling iron bars in the top structure"

The rate of descent is affected by many factors, and study of these factors is key to understanding the demolition

[kewlboy567]

The building did not fall as perfect as you illustrate. The building did not fall one floor at a time each moment. Yes it was one floor but as it falls more it would gain more momentum and power and floors under those directly being curshed by the top would also crush.

[femr2]

kewlboy...You are quite correct. The simulation employs techniques and simplifications similar to those used in a number of different mathematical and physics based analyses of the events.

The model is for a 'perfect' collapse focussing only upon energy transfers and resulting collapse time implications.

All simplifications work in favour of continued collapse. All simplifications act in favour of the 'official theory', though I do not support it.

[femr2]

kewlboy..."as it falls more it would gain more momentum and power and floors under those directly being curshed by the top would also crush."

Momentum and KE are included in the simulation. As each impact occurs, the mass of the impacted floor is added to the mass of the descending 'cap' and the mass of the cap as a whole is used in subsequent collision calcs.

I assume you mean that I am not including elastic strain and impulse implications ?

[kewlboy567]

Yes i do, At this point no one has "Fact" on what happened everyone has theories some believed more then others.

[femr2]

kewlboy...I'll be including the time required for elastic deformation at each floor level soon. Including multi-floor and tower structure energy absorbtion implications is probably too complex for the purpose here, which is to help people understand the basics.

The details you are mentioning would be more suited to a FEA simulation, which this is not, and does not pretend to be.

I'm happy to consider additions which fit into the model tho...

[kewlboy567]

once you have the new model up contact me and i will be happy to discuss with you. over it al, at this point what you have is a "imperfect" simulation which that imperfection the smallest bit makes a big difference.

[femr2]

kewlboy... Okay, although you do realise that inclusion of the additional factors will increase calculated collapse times, increase potential energy requirements and via the structure absorbing elastic impulse energy impede collapse progression significantly ?

[kewlboy567]

yes i do seeing that the floors would be collapsing in larger numbers and much more quickly.

[femr2]

kewlboy...Not really no, as it's not the floors which would be absorbing energy. It would be the external and central core columns which would absorb the kinetic energy of the impacts (elastic strain). Full inclusion of elastic strain will imply failure in collapse progression after a small number of floors due to lack of available energy.

[kewlboy567]

However the second impact on WTC tower 2 would have also effected the integrity of WTC tower 1. This would have weaken'd the total integrity of all floors. This would also make the steel gerters thus this would also increase the fall rate of WTC tower 1.

[femr2]

kewlboy...No, it wouldn't. lol.

[swingdangler]

No it wouldn't. If anything, you get a few windows blown out. That's it.

[femr2]

Please download the data-sheet available for the simulator, containing all of the calculations and data used:

femr2. ucoz. com

[wolly600]

u make these urself?

[fulcrumpete]

Your argument is seriously flawed. A building is only as strong as its weakest links.

The bolts which held it together were sheared as the upperblock crashed down onto the lower block.

They were never designed to arrest a collapsing dynamic load. Only to hold the structure together under a static load.

[femr2]

The parameter 'Kin Supp' specifies the energy you are referencing. It is the average energy required to sever the connections on a single floor. The value is derived from numerous studies from authors such as Bazant and Greening, who derive similar values even though each author approaches the calculation from a different 'plane' of thought. Bazant quantifies the energies involved for the aircraft impact, whereas Greening quantifies from a structural elastic shearing perspective.