Tower Collapse Questions for Critical Thinkers

Hokulele said:
So the connections between the glass and supports don't come into play at all?

Strange.
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Initial contact is between top glass element (let's call it A80) and bowling ball (C)! Not strange at all!

Let's assume that the bowling ball, C, is rigid and does not absorb any energy at impact, i.e. all kinetic energy, E, is applied to the top glass element, A80.

Let's now assume that A80 is broken and that exactly energy E is used for that!

What does it mean, apart from A80 being broken.

Well, it means that the motion of C, the bowling ball, has temporarily come to absolut rest (all kinetic energy applied by C has been used to break A80).

Of course, C will now start a new drop of 500 mm, and, if it misses the connections between A80 and A79, it will impact the next glass element below, A79, and apply its new kinetic energy there (due to a 500 mm drop).

And maybe now the glass element, A79, will not be broken ... and C bounces on A79!

Another possibility is that C is not rigid and thus absorbs some of the energy E at impact! How much energy (E) C and the assembly A1-A80 absorb depends on the structures of C and A.

C may have a defect and may crack into two pieces at impact with A80, etc, etc. Structural damage analysis of collisions between two structural assemblies is really a fascinating subject (that I have studied for 40+ years).
 
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Heiwa said:
Let's assume that the bowling ball, C, is rigid and does not absorb any energy at impact, i.e. all kinetic energy, E, is applied to the top glass element, A80.

Let's now assume that A80 is broken and that exactly energy E is used for that!
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So nothing is transferred to the connections between A80 and the supports?

Strange.
 
Hokulele said:
So nothing is transferred to the connections between A80 and the supports?

Strange.
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Not really - the force F applied to the top glass element A80 at impact by C must pass through the glass element A80 to the supports via the connections. Evidently, immediately after impact that force F manages to pass A80 and is thus applied to the supports/connections, but when A80 breaks, the force F becomes 0 again, while C starts its new drop.

If the supports/connections are rigid, no energy is absorbed there - only in the top element A80 (and C, if not rigid).

As I say, it is quite simple. Just do the analysis, step by step, and you'll find out what happens and the problem is solved.
 
R.Mackey said:
The videos with which you are not familiar describe a particular type of demolition, in which a single floor's worth of supports is suddenly destroyed through cables and hydraulics. This leaves an upper section to fall upon the lower portion, which is frequently much larger than the upper part. The entire structure is destroyed, despite no weakening at all being applied to the lower portion.
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So, a gravity driven collapse where once the collapse starts it becomes unstoppable. Yet Google shows that no one has yet labeled verinage demolition as "psy-ops". C'mon, someone out there has to think that verinage demolition is trickery designed to fool the masses as to the true nature of 9/11.
 
Oh good grief, Heiwa's attempting to hold court again. I almost prefer kylebisme.
But neither are very interesting. Being repetitive and resistant to comprehension, they're brilliant at.
 
I'm keeping out this thread if incomprehensible threader stupidy, as the rest of you are doing a far better job of debunking the OP crap. However I just wanted to remind the casual observer that our friend Heiwa, who claims to be an expert, lied about the causes of something as simple as the Ronan Point collapse and has failed to substantiate his position ever since. His opinion should be set at naught.
 
kylebisme said:
The path of least resistance, in regard to matter, is directly related to Newton's third law. The difference between the law and the principle here is; an object in motion will always stay in motion unless acted upon by an outside force, while an mass will only follow the path of least resistance unless it exerts work to do otherwise.
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Newton's Third Law is the "action and reaction" one.
You're thinking of Newton's First Law, I believe.

You really must stop your scientific bluffery.
 
kylebisme said:
For instance, find yourself a nice grassy hill, lay down, and let yourself roll down it. Doing so, you will follow the path of least resistance
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You need to think through your analogies better. If you start to roll down a hill and there is a bump in your path you will not magically go around it. What happens when you approach that bump will depend on your built-up momentum and the size and shape of the bump.

I am pretty sure you have been made aware of how important the concepts of momentum and/or inertia are to the WTC collapses.
 
Heiwa said:
<snip>

As I say, it is quite simple. Just do the analysis, step by step, and you'll find out what happens and the problem is solved.
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Translation:




Heiwa has indeed joined the Mothra Movement. Welcome aboard.
 
kylebisme said:
Ah, yeah, they were mentioned to me in a PM by another member erlier as "the French demos", I simply wasn't familiar with the term "verinage". Anyway, the videos you posted do show an unsual form of controlled demolition, using cables to pull out supporting structure rather than explosives to blast it out. Furthermore, note how the velocity of the upper mass decreases after coming into contact with the lower mass, demonstrating the resistance provided by that lower mass. Also consider how much more the deceleration would have been had that lower structure been not simply concrete but rather also framed with steel.
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ah... so now you are going to Tony S's missing jolt?

really?

that is highly amusing.

shift shift shift.

Do you know what else it shows? That Bazant was right, and BLGL fully explains what happened to the towers...
 
kylebisme said:
Sure, like if you stack 80 glass coffee tables on top of each other and then drop a bowling ball on that; once it starts, it's all over, eh? Assuming 10mm glass with a 1 kg/mm/mm tensile strength spaced 500mm apart, and a 10 kg ball with a 200mm diameter given say 100m over the top of the structure just for fun, how close to free fall would expect that ball to get after connecting with the first sheet of glass?
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I just love truther analogies; coffee tables, Pizzas boxes, cheese, trees and crushed cookies.

It’s like an 8 year old learning Physics in the kitchen. Wouldn’t it be nice if life was that easy?

Oh well coffee break over, gotta go work on my suspension system. Yeah I’m modelling it with spaghetti, anyone confident enough in that to by a new Merc????

Woof!
 
R.Mackey said:
Oh, my aching head.

...



In my last reply, somewhat in jest, I referred you to the "integral sign" in my derivation. Apparently you really don't know what that means. The division by 3 is not at all arbitrary; it is, in fact, a pretty good representation of the actual Tower. Anyway, what we learn from this is that you cannot follow even a simple potential energy calculation, even when all the work is shown for you and dumbed down to a high school sophomore level.
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You knew that going in, Ryan!
That did not take a rocket scientist to figure out, but luckily we have a couple of them available.
R.Mackey said:
No. A Newton is a unit of force. Structural integrity is not equivalent to a force. As I said, the structural integrity is not a well defined quantity. How well a structure will perform under load is not an intrinsic property of the structure. You have to specify the conditions in much more detail. For instance, two forces that arrive at different angles may have dramatically different effects on the structure.

This is why my calculation does not attempt to gauge "structural integrity." Can't be done. Instead, I looked at energy absorption. And that, again, is what you asked for, even though you've run far away from that discussion ever since.
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fixed that---From my experience, we don't define Structural integrity, except as a SF for worst case combined loads--then add 50% MUF

R.Mackey said:
I cannot emphasize enough how nonsensical the above is.

"Interia" is not "elements of structural strength." Inertia is, depending on how you're looking at it, either mass or momentum. It has units of kilograms or Newton seconds, respectively. The WTC Towers have the same inertia before and after the collapse, although clearly the structural integrity before versus after is radically changed.
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To be fair, "I" is referred to as Moment of Inertia, and strength is a function of "I", as in P*L3/(48*E*I)
However, the BS comes when half-educated (at best) troofers grab a partial name and use it as something else.
Moment of inertia /= inertia.
R.Mackey said:
The point which you keep missing, for reasons that are now only too obvious, is that the timing of the "crush-down" style collapse is primarily governed by the mass of the structure and its contents. It is momentum transfer that slows the descent. The strength of the lower block also slows the descent, but not much, practically a round-off error. You could double the strength of the WTC Towers without changing the mass and hardly notice the difference.....

I'm done with you unless you want to learn. In that case, we can help.
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Im joining you theree.
Everybody--please don't quote the guy, as that will force me not to read what you write!
 
tsig said:
Ohm's law:

E=IR is simply an equation that says "the voltage is equal to the current times the resistance". It does not mention paths or renting property.
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Indeed, through several years of post secondary schooling and 30 years of experience in the feild of electronics I have never heard the term "path of least resistance" used by my peers.

I understand implicitly that current will be higher in circuits of less resistance(given the same voltage supply) and I suppose one could, if one had some reason to do so, describe that as the electrons shunting to the path of least resistance.

However the analogy quickly breaks down given that in a complex piece of equipment several ciruits fed from the same power supply will have different curents than others. If the electrons were required to flow in the path of least resistance then current would be flowing in only one of those circuits.

It would suck for any parallel circuitry:D
 
jaydeehess said:
Indeed, through several years of post secondary schooling and 30 years of experience in the feild of electronics I have never heard the term "path of least resistance" used by my peers.

I understand implicitly that current will be higher in circuits of less resistance(given the same voltage supply) and I suppose one could, if one had some reason to do so, describe that as the electrons shunting to the path of least resistance.

However the analogy quickly breaks down given that in a complex piece of equipment several ciruits fed from the same power supply will have different curents than others. If the electrons were required to flow in the path of least resistance then current would be flowing in only one of those circuits.

It would suck for any parallel circuitry:D
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that term never really made sense to me when i thought about it in a complex way
i hated using it when i was trying to teach people at my old job (believe it or not, i was the head tech and trainer before i left lol) as i felt it could confuse them (which wasnt hard to do and hence my omega comment earlier) but you have to start somewhere lol

im a field tech (and owner now) and i work on a lot of 100% electric vehicles (forklifts, jacks, cushmans etc)
even though i cant engineer a circuit (well at least a very complex one)
understanding how it works is crucial to successful troubleshooting (and the downfall of many techs in my field)

i was tempted to post earlier:
"if that was a law of electricity your computer would never work"
but to most here thats pretty obvious lol
 
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