Well, you are not much of a civil engineer. You missed the point where the stress loads are adjusted among columns at the speed of sound in hot steel. Essentially instantaneous. The whole failure process occurs in a tiny fraction of a second. There is something called inertial confinement, mostly used in nuclear weapons, but the idea is that a dynamic process is happening faster than the rest of the system mass can respond to it. The upper floors would have no time to tilt in a fraction of a second when the tilting moment would be shifting at a frequency close to that of audible sound.
To the contrary, I am espousing no conspiracy theory at all. I am only explaining the dynamics of the collapse. I come from the aircraft and weapon industry, which is a derivative of civil engineering. I'm used to the idea of system failures occurring in milliseconds. I rather get the idea that you are convinced of.a conspiracy theory.
It amuses me (darkly) that the unofficial motto of this site is "Question Everything," but it does not seem to apply to questions against the popular conspiracy theories.
I've come to my own conclusions and admittedly remain open on certain matters, so don't preach to me about questioning. your theory is junk. if there's hypothetically 100 support columns at the floor/s where fire occured, how many do you think only need to be compromised and super heated to cause this beautifully symmetrical pancake collapse to happen because all of the previously supported load has instantaneously transferred to these remaining columns. your argument suggests that upon failure of the burnt columns that the loads then uniformly transfer to the remaining columns causing them to fail. this is illogical. certain columns will be significantly overloaded but others might hardly change and yet others do to torque/tilt will actually result in reduced load while some could even go from compression load to tensile load.
don't bother responding. you're a clown and I'm done with your fantasy. frankly I think you're a shill, glowie or something and you should be deported but have your fun trying to sew discord and challenge independent thinkers here
The point is that this happens when the columns have all nearly reached their load limit (some already have been collapsed). All it takes is a final critical column to fail, and the chain reaction proceeds at the speed of ~17,000 feet per second. Spreading out to a 100-foot radius would take about 6 milliseconds before all columns would have failed (every single failure would shift the constant load across a decreasing number of columns, all of which are at the load limit). The compressive failures would be in shear. If the shear is a 45-degree fracture across a 2-foot column, the shear path would be 3 feet and the crack would propagate in 0.176 millisecond. A hundred columns fracturing in series (slowest case) and a load redistribution time of 6 milliseconds would add up to 23.6 milliseconds. The mass of the upper stories is not going to tilt in the span of 20-30 milliseconds. It might shiver, but then it would commence the plunge.
This is the way it works. The loads do not go away. The structural bearing strength of the columns goes away. And when they collectively weaken to their load limit, all it takes is for one column to fail in order to start the devastating chain reaction collapse. How fast do you think loads are transmitted through steel? Any pressure load transmits by sound, and the loads go as fast as sound travels in metal. When a load exceeds the critical strength of a column, how long does it take a crack to propagate? Only at the speed of sound. And then the load-to-bearing ratio simply gets worse with each column failure. There is no dramatic waiting around. Nature operates as fast as it can.
Can demolition crews time their charges to within milliseconds? The clue that you don't "get it," is your ridiculous assertion that a demolition crew would need to destroy only a few columns. As I have clearly explained, the net bearing strength of all columns taken together would have to be reduced to a safety factor of 1, and then all the columns would have to be severed. (Making reference to a failed demolition only says something about failed demolitions. Since there was no demolition, the reference is useless.)
I am an engineer with 3 degrees. In this exchange I have explained matters quantitatively. You have no refutation of this description of what happened, which conforms to the facts and is based on strict scientific principles of failure propagation. You bluster, denounce, deny, accuse, insult, and wish ill upon me. Not the best demonstration of a scientific or truth-seeking spirit.
I've seen this too many times. When the conversation gets to a point where the opponent cannot cope with the technical details or refute them, he resorts to name-calling and condemnation. I think you have outed yourself.
Well, you are not much of a civil engineer. You missed the point where the stress loads are adjusted among columns at the speed of sound in hot steel. Essentially instantaneous. The whole failure process occurs in a tiny fraction of a second. There is something called inertial confinement, mostly used in nuclear weapons, but the idea is that a dynamic process is happening faster than the rest of the system mass can respond to it. The upper floors would have no time to tilt in a fraction of a second when the tilting moment would be shifting at a frequency close to that of audible sound.
To the contrary, I am espousing no conspiracy theory at all. I am only explaining the dynamics of the collapse. I come from the aircraft and weapon industry, which is a derivative of civil engineering. I'm used to the idea of system failures occurring in milliseconds. I rather get the idea that you are convinced of.a conspiracy theory.
It amuses me (darkly) that the unofficial motto of this site is "Question Everything," but it does not seem to apply to questions against the popular conspiracy theories.
I've come to my own conclusions and admittedly remain open on certain matters, so don't preach to me about questioning. your theory is junk. if there's hypothetically 100 support columns at the floor/s where fire occured, how many do you think only need to be compromised and super heated to cause this beautifully symmetrical pancake collapse to happen because all of the previously supported load has instantaneously transferred to these remaining columns. your argument suggests that upon failure of the burnt columns that the loads then uniformly transfer to the remaining columns causing them to fail. this is illogical. certain columns will be significantly overloaded but others might hardly change and yet others do to torque/tilt will actually result in reduced load while some could even go from compression load to tensile load.
under your ridiculous theory demo crews only need to properly blast a few columns to get an entire building to pancake nicely. https://www.dailymail.co.uk/news/article-1239841/Youre-doing-wrong-Chinese-demolition-men-accidentally-create-leaning-tower-Liuzhou.html
don't bother responding. you're a clown and I'm done with your fantasy. frankly I think you're a shill, glowie or something and you should be deported but have your fun trying to sew discord and challenge independent thinkers here
The point is that this happens when the columns have all nearly reached their load limit (some already have been collapsed). All it takes is a final critical column to fail, and the chain reaction proceeds at the speed of ~17,000 feet per second. Spreading out to a 100-foot radius would take about 6 milliseconds before all columns would have failed (every single failure would shift the constant load across a decreasing number of columns, all of which are at the load limit). The compressive failures would be in shear. If the shear is a 45-degree fracture across a 2-foot column, the shear path would be 3 feet and the crack would propagate in 0.176 millisecond. A hundred columns fracturing in series (slowest case) and a load redistribution time of 6 milliseconds would add up to 23.6 milliseconds. The mass of the upper stories is not going to tilt in the span of 20-30 milliseconds. It might shiver, but then it would commence the plunge.
This is the way it works. The loads do not go away. The structural bearing strength of the columns goes away. And when they collectively weaken to their load limit, all it takes is for one column to fail in order to start the devastating chain reaction collapse. How fast do you think loads are transmitted through steel? Any pressure load transmits by sound, and the loads go as fast as sound travels in metal. When a load exceeds the critical strength of a column, how long does it take a crack to propagate? Only at the speed of sound. And then the load-to-bearing ratio simply gets worse with each column failure. There is no dramatic waiting around. Nature operates as fast as it can.
Can demolition crews time their charges to within milliseconds? The clue that you don't "get it," is your ridiculous assertion that a demolition crew would need to destroy only a few columns. As I have clearly explained, the net bearing strength of all columns taken together would have to be reduced to a safety factor of 1, and then all the columns would have to be severed. (Making reference to a failed demolition only says something about failed demolitions. Since there was no demolition, the reference is useless.)
I am an engineer with 3 degrees. In this exchange I have explained matters quantitatively. You have no refutation of this description of what happened, which conforms to the facts and is based on strict scientific principles of failure propagation. You bluster, denounce, deny, accuse, insult, and wish ill upon me. Not the best demonstration of a scientific or truth-seeking spirit.
No you’re not. You’re a glowing shill
I've seen this too many times. When the conversation gets to a point where the opponent cannot cope with the technical details or refute them, he resorts to name-calling and condemnation. I think you have outed yourself.