OvermodNow, in order to produce liquefaction, you need a motion of water sufficient to fluidize an appreciable volume of soil for a considerable time under a train's weight. A very likely component of force to produce such motion would be vibration, and a good engineer can calculate frequency ranges for a given grade or subgrade that would be most efficient at producing it and compare those to actual vibration characteristics produced by an oil-train consist. The argument, however, is slightly different: would liquefaction producing purely a vertical displacement of the track result in a derailment? I find this relatively unlikely based in part of my knowledge of the dynamic response of three-piece trucks and the experience of the Army demolitions people investigating the best ways to derail trains in WWII. This is not to dismiss the idea that liquefaction is related in some way to the incident, only to note that concluding liquefaction IS either the expedient cause or a major contributor to the incident is at best premature. Possibilities do, I think, include the idea of liquefaction-related settlement under one 'side' of the train, or (as noted) lateral slip of some part of the grade/subgrade resulting in impairment of track geometry. I would note that neither of these, if they were present, seem impossible of remediation within the timeframe and apparent resource allocation BNSF provided after the incident;
When I opine that liquefaction caused the derailment, I have suggested that the support gave way under the weight of the train. However, I do not mean to suggest that the center of the liquefaction zone was necessarily located dead center under the track. Indeed, it might have been located off center to the extent that some of the bank slope may have dropped away due its own weight under the influence of liquefaction as the train vibrated the soil during its passage. And then that dropping soil may have reduced the support of the train. Actually, liquefaction may have spread to the entire fill from side-to-side and top-to-bottom. In cases where the liquefaction occurred without causing bank slope to slide, it could nevertheless liquefy soil that did not require cohesiveness to remain stationary. In that case, the added weight of the train would merely drop into the liquefied soil without any sliding away of soil having occurred.
I have seen those videos (that you mention) showing tests of how much track damage it took to derail trains. And it was surprising how much it took to derail a train. However, I would not conclude that it indicates that liquefaction would be unlikely to cause enough loss of support to derail a train.
This is because the video tests were on solid roadbed with ballasted ties, and the only derailing factor was the removal of various lengths of rail. And also, that equipment was relatively light compared to a loaded oil train of today. So, I think liquefaction would have the potential to very effectively cause a derailment.
If the entire width of track bed lost its ability to support the train, the track would suddenly drop under the weight of the train to the point of being submerged in the muck. This reduction of support would likely be irregularly distributed so that the cars would dip and rise as conditions vary in direction of travel as well as side to side on the track. This would place very high stresses on the track which might break rail and ties or cause the rail to tip over or separate from the ties. Or the irregular movement might just directly derail cars as their wheels momentarily cleared the rail head.
It would be interesting to know whether the crew recalls feeling any sort of instability in the track as they were passing through the flood zone where the derailment occurred. It is possible that liquefaction began to develop from the passage of previous trains.
tree68Wouldn't that more or less have been the case if the water level of the river were uncharacteristically high, completely submerging the roadbed?
I don't think so. The walls of the box confine the energy, which is brought into the system, to the area of the box. Without the walls or a box with a larger area the same energy would have activate a larger area slowing the process. In the field the wall would need to be the surrounding soil. It will never be as rigid as a metal wall.
What happens in reality is a question of the local situation. Is the soil condition, allowing liquefaction, only a local problem on a number of sq ft or a general problem along the fill. So the results of this laboratory test cannot be transfered one-to-one to the field.Regards, Volker
VOLKER LANDWEHRThe soil is encased in a box, therefore the water has no way to exit to the side accelerating the liquefaction. The missing foundation don't have any influence on the process.
Wouldn't that more or less have been the case if the water level of the river were uncharacteristically high, completely submerging the roadbed? The effect would have been to place the roadbed in suspension, with the passing train simply stirring the pot.
We've noted that four foot surge - that may have placed the water level well above the levels to which the MOW forces were accustomed.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
One only needs to stand near the UP Geneva Sub tracks (generally very well maintained) as a train with some wheels with flat spots (usually covered hoppers or box cars, not auto transporters, tank cars or IM flats) goes by to feel the strong vertical shocks.
RDG467Interesting video. I believe you'd agree that this is not *completely* representative of real life, because the structures on the table did not have any foundations, they merely sat on the soil's surface.
Sure I agree. Therefore I wrote of a laboratory video. The soil is encased in a box, therefore the water has no way to exit to the side accelerating the liquefaction. The missing foundation don't have any influence on the process.
RDG467Plus, the shaking force was parallel to the ground surface, not perpendicular, as would occur under the relatively low-frequency cyclical loading of a unit oil train. Which is mostly absorbed by the wooden ties and ballast anyhow.
The effect would have been the same with vertically oriented vibrations. Horizontal vibrations are only easier to generate in laboratory.
Here is a homemade video showing the liquefaction caused by vertical shocks: https://www.youtube.com/watch?v=b_aIm5oi5eAAnd here is another video that had already been linked showing how easy liquefaction is caused under special circumstances: https://www.youtube.com/watch?v=Rd6W2aP2dkA
The last time I stood beside the track on Tehachapi the earth shook and the vibrations showed in the video. The camera stood on a tripod about 15 ft off the track.
Again, there are many possible causes for the derailment and I don't rule out Liquefaction.Regards, Volker
VOLKER LANDWEHR Under the right conditions there is not much vibration over long times necessary. Here is a laboratory video from RWTH Aachen, a German technical university showing the process: https://www.youtube.com/watch?v=ZMWKTuRgJjY I'm not saying liquefaction was the cause but I in my opinion it shouldn't be ruled out.Regards, Volker
Under the right conditions there is not much vibration over long times necessary. Here is a laboratory video from RWTH Aachen, a German technical university showing the process: https://www.youtube.com/watch?v=ZMWKTuRgJjY
I'm not saying liquefaction was the cause but I in my opinion it shouldn't be ruled out.Regards, Volker
Interesting video. I believe you'd agree that this is not *completely* representative of real life, because the structures on the table did not have any foundations, they merely sat on the soil's surface.
Plus, the shaking force was parallel to the ground surface, not perpendicular, as would occur under the relatively low-frequency cyclical loading of a unit oil train. Which is mostly absorbed by the wooden ties and ballast anyhow.
RDG467So, it appears that either the 9th or 10th car was the first to derail.
That early in the train suggests the simple liquefaction scenario is unlikely. It takes time for the vibrations to do their worst, and on an important main line with good ballast, surface and CWR the vibration is much reduced.
EuclidYou say I presented an opinion that you know to be a misconception.
No - an opinion is just that - a person's view of something. A misconception is an erroneous belief that something is the case, when in fact is isn't. See my example of the warning sign. It should look familiar.
EuclidAnd then you go on to state all of your opinions about why my opinion about the Doon wreck is wrong and how it is unjust for me to state it. You have no problem with all of your opinions because you consider them to be facts.
Never said your opinions are wrong - only that there are often other factors to consider. And my opinions are just that, opinions. You're the one casting them as facts. If I'm going to present something as fact, I'll back it up, as I did with the river levels.
There are things I'm an expert on, things I'm simply knowledgable about, and things I'm just John Q Public on. Just like everybody else.
As for your other questions - I don't know, which is why the word "apparently" appears so often in my posts. My conclusions are based on what I've seen and our discussions here. If those conclusions are proven to be wrong - so be it. We'd all love to see the information that would make such a judgment possible, although, as discussed, we probably never will.
tree68My concern in the first Doon thread was the implication that the crew should have slowed down simply because the water level was judged to be high by a poster here. My entire point was that up until the crew actually saw the water was as high as it was (at 0430, in the dark), they had no reason to do so, as it appeared the railroad itself was not concerned.
I was the poster you mention here. And I presented the facts as they were available to the public, sic also to BNSF. But one needs to open the links and read them.
Neither Euclid nor me said the railroaders needed to slow down (on sight). I said that BNSF should have issued a speed restriction.
tree68Why the railroad was not concerned is a question in and of itself, as has also been discussed.
It has been discussed but never really answered. Some here even negated that it was an unusual high highwater, though there was the desaster declaration by the state of Iowa. So we disagree on the question is Rule 6.21 applicable or not. And here the circle-the-wagons mentality came into play.
tree68Again, the railroad apparently didn't feel the water level was a problem or they would have issued directives to that effect. To our knowledge, that was not done.
That doesn't naturally mean BNSF was right in its decision. If there was an accident one needs to question all decisions that might have led to it. Defending is not the way to go.
tree68Even now, as has been mentioned, it has not been established (to our knowledge) that the water level was even a factor. The asteroid idea is a little facetious, but a broken wheel/axle/bearing is not out of the question. It occurs to me that an overheated bearing suddenly being cooled might be problematic.
Euclid and me have both acknowledged that there are a lot of possible causes. Euclid came to his conclusion that liquefaction was the cause. I think it would have been appropriate for BNSF to issue a speed restriction based on rule 6.21. I haven't made up my mind regarding the causes. In the case of liquefaction I tried to help with facts.
tree68OTOH, unless the head end backed up, the fact that they travelled only as far as they did after the derailment suggests that they had already reduced speed, for whatever reason.
Looking at the pile-up of the tank cars I doubt it.
tree68 VOLKER LANDWEHR A last point, you blamed for covering the bases Huh?
Sorry, the sentence read as follows: A last point, you blamed Euclid for covering the bases.
Your post and my answer all are opinions. Some opinions are backed by facts others perhaps not. So where is the problem? Perhaps that we started to blame a railroad? Please, think about it.Regards, Volker
tree68 I'm far less concerned with a "wrong" opinion than I am a misconception presented as fact. My concern in the first Doon thread was the implication that the crew should have slowed down simply because the water level was judged to be high by a poster here. My entire point was that up until the crew actually saw the water was as high as it was (at 0430, in the dark), they had no reason to do so, as it appeared the railroad itself was not concerned. Why the railroad was not concerned is a question in and of itself, as has also been discussed. My train of thought continued right through the introduction of Rule 6.21 to the discussion, as it was never established that any of the conditions in the rule were met prior to the derailment. Again, the railroad apparently didn't feel the water level was a problem or they would have issued directives to that effect. To our knowledge, that was not done. Even now, as has been mentioned, it has not been established (to our knowledge) that the water level was even a factor. The asteroid idea is a little facetious, but a broken wheel/axle/bearing is not out of the question. It occurs to me that an overheated bearing suddenly being cooled might be problematic. OTOH, unless the head end backed up, the fact that they travelled only as far as they did after the derailment suggests that they had already reduced speed, for whatever reason.
I'm far less concerned with a "wrong" opinion than I am a misconception presented as fact.
My concern in the first Doon thread was the implication that the crew should have slowed down simply because the water level was judged to be high by a poster here. My entire point was that up until the crew actually saw the water was as high as it was (at 0430, in the dark), they had no reason to do so, as it appeared the railroad itself was not concerned.
Why the railroad was not concerned is a question in and of itself, as has also been discussed.
My train of thought continued right through the introduction of Rule 6.21 to the discussion, as it was never established that any of the conditions in the rule were met prior to the derailment. Again, the railroad apparently didn't feel the water level was a problem or they would have issued directives to that effect. To our knowledge, that was not done.
Even now, as has been mentioned, it has not been established (to our knowledge) that the water level was even a factor. The asteroid idea is a little facetious, but a broken wheel/axle/bearing is not out of the question. It occurs to me that an overheated bearing suddenly being cooled might be problematic.
OTOH, unless the head end backed up, the fact that they travelled only as far as they did after the derailment suggests that they had already reduced speed, for whatever reason.
You say I presented an opinion that you know to be a misconception. If you believe that I am presenting an opinion, how can you claim I am presenting it as a fact? Even if my opinion is wrong, I have the right to believe that it is correct. Yet you seem to regard that as some type of injustice that you have the right to publically accuse me of. We get to have opinions.
And then you go on to state all of your opinions about why my opinion about the Doon wreck is wrong and how it is unjust for me to state it. You have no problem with all of your opinions because you consider them to be facts.
You say that the crew had to see the water before they could be expected to slow down. How do you know they did not see the water? What if they did see the water and did not slow down? You say it appears that the railroad was not concerned about the high water. How do you know that the apparent lack of concern means that the company was justified in not requiring the crew to slow down? What if the railroad misjudged the need to slow down? What if they should have issued directives to slow down, but failed to do that? What if they did issue directives, and the crew failed to comply with them? What if the directives were inadequate?
Your set of refutations of my opinion is just as much opinion-based as my opinion. And yet you feel that it is wrong for me to offer my opinion.
OvermodHas it been established where the actual point of derailment in the consist was?
A key point, particularly if the cause was mechanical, as the train may have derailed a distance of several cars before one of them dug in and stopped, causing the rest of the pile-up.
VOLKER LANDWEHRMany here believe that only experts can be right and that is pure nonsense.
Yes, and also pure nonsense that anyone who claims to be an expert is one.
VOLKER LANDWEHRA last point, you blamed for covering the bases
VOLKER LANDWEHRWhen he offers a, in your view wrong, opinion, and is called, I find it only natural to try to back it up.
I'm far less concerned with a "wrong" opinion than I am a misconception presented as fact. For instance, yellow diamond traffic warning signs don't "take effect" like black and white traffic regulation signs do. In fact, they effectively have a "halo" of some 600 feet before the sign that the MUCTD considers as part of the distance for placing such signs to effectively warn of an upcoming condition.
Overmod
Overmod Let me slam the door on any line of argument or discussion that equates "vibration" and "shear failure" here.
It is not an equation but vibrations can cause slope failures if shear resistance is exceeded.
OvermodThe argument, however, is slightly different: would liquefaction producing purely a vertical displacement of the track result in a derailment? I find this relatively unlikely based in part of my knowledge of the dynamic response of three-piece trucks and the experience of the Army demolitions people investigating the best ways to derail trains in WWII.
I think that depends on how the track deforms. But as you said the liquefaction isn't necessarily centric under the fill. Here is a picture I first found in an German University publication identifying the cause of the slope failure as liquefaction through an earthquake (Seattle, 1965): https://upload.wikimedia.org/wikipedia/commons/thumb/f/fb/1965_Seattle_EQ_damage.tif/lossy-page1-1000px-1965_Seattle_EQ_damage.tif.jpg
For me liquefaction is one possible cause among a lot others. In contrast to Euclid I haven't made up my mind because of too few information. I tried to keep the discussion on a factual level.Regards, Volker
tree68 VOLKER LANDWEHR I'm always surprised how easily people pick on Euclid's post just because he is Euclid but not willing to contribute anything and hide behind excuses. If someone acuses someone else of writing garbage he should proof/explain it. Otherwise I can't take this person seriously. Usually, behavior such as that has some basis in past experience. I don't think anyone has picked on Bucky just because he's Bucky. He's established a reputation.
VOLKER LANDWEHR I'm always surprised how easily people pick on Euclid's post just because he is Euclid but not willing to contribute anything and hide behind excuses. If someone acuses someone else of writing garbage he should proof/explain it. Otherwise I can't take this person seriously.
Usually, behavior such as that has some basis in past experience. I don't think anyone has picked on Bucky just because he's Bucky. He's established a reputation.
I think he got a reputation attached. By the way a repution is not more than a facade. Only when you see what backs a reputation you can judge it. And there lies a problem some have with Euclid. He doesn't give his credentials and that seems to unsettle some.
Many here believe that only experts can be right and that is pure nonsense. Instead of checking what he says, and he often supports his opinions with citations, some react as if everything must be wrong, him not being an expert. Reading thinks? Why, facts could come into the way of preocupation.
tree68 VOLKER LANDWEHR I find it totally okay that someone offers an opinion though he is not sure of all detail or even might have some wrong. And this has been a part of the issue in the past. Bucky offers an opinion which is factually incorrect, then bases further conclusions on that opinion as though it was fact. If called on the mistaken conclusion, "yes, but."
VOLKER LANDWEHR I find it totally okay that someone offers an opinion though he is not sure of all detail or even might have some wrong.
And this has been a part of the issue in the past. Bucky offers an opinion which is factually incorrect, then bases further conclusions on that opinion as though it was fact. If called on the mistaken conclusion, "yes, but."
In the early stages of a thread the "yes, but" is what he explains in his post. The "but" can mean disagreement or asking for clarification. If it gets repetitive I leave the thread.
Euclid should learn to recognize when he can't convince anybody anymore in thread and stop his repetitions.
When he offers a, in your view wrong, opinion, and is called, I find it only natural to try to back it up. There is a difference between some here and Euclid and e.g. me. We don't naturally believe experts. I had to clean up a number mistakes of so called experts that tend to question them.
Going in these discussions/speculations open minded and nonbiased would help a lot.
The first Doon thread is a good example for another phenomenon. When railroads are questioned the circle-the-wagons mentality comes through regardless of fact. The conclusions I drew might have been wrong but by ignoring the facts some provoke the "yes,but".
A last point, you blamed for covering the bases. What do you think what NTSC does? They go through the evidence and make a long list of possible causes. Cause by cause is checked against the evidence to eliminated causes. Often you need further investigations and sometime you need to get back to a cause you thought you eliminated already.
So covering the bases is a natural process in accident investigation.Regards, Volker
EuclidWhen vibration produces liquefaction, it does result in a shear failure of the soil, but if it were not for the vibration, there would be no liquefaction and thus no shear failure (in at least some cases). So I don't understand why you seem to rule out vibration and replace it with shear failure.
The 'shear failure' is subsequent to the liquefaction action, no matter how generated, and while it might be taken as the 'proximate cause' of the actual derailment there are alternative methods of inducing a shear failure that do not involve the specific physics observed for liquefaction. Let me slam the door on any line of argument or discussion that equates "vibration" and "shear failure" here.
Now, in order to produce liquefaction, you need a motion of water sufficient to fluidize an appreciable volume of soil for a considerable time under a train's weight. A very likely component of force to produce such motion would be vibration, and a good engineer can calculate frequency ranges for a given grade or subgrade that would be most efficient at producing it and compare those to actual vibration characteristics produced by an oil-train consist. The argument, however, is slightly different: would liquefaction producing purely a vertical displacement of the track result in a derailment? I find this relatively unlikely based in part of my knowledge of the dynamic response of three-piece trucks and the experience of the Army demolitions people investigating the best ways to derail trains in WWII. This is not to dismiss the idea that liquefaction is related in some way to the incident, only to note that concluding liquefaction IS either the expedient cause or a major contributor to the incident is at best premature.
Possibilities do, I think, include the idea of liquefaction-related settlement under one 'side' of the train, or (as noted) lateral slip of some part of the grade/subgrade resulting in impairment of track geometry. I would note that neither of these, if they were present, seem impossible of remediation within the timeframe and apparent resource allocation BNSF provided after the incident; it would be interesting to hear mudchicken's analysis of the situation if he is inclined to comment based on what information we know.
Has it been established where the actual point of derailment in the consist was?
tree68 Euclid I think you’d be surprised at how many people can see through what you are up to. You know, I was going to reply to that, but it's not worth it. If I was the only one questioning your posts, I might agree, but that's not the case. I've been purposely staying out of most of the latest conversations.
Euclid I think you’d be surprised at how many people can see through what you are up to.
You know, I was going to reply to that, but it's not worth it.
If I was the only one questioning your posts, I might agree, but that's not the case. I've been purposely staying out of most of the latest conversations.
Euclid I think you’d be surprised at how many people can see though what you are up to.
tree68 VOLKER LANDWEHR I'm always surprised how easily people pick on Euclid's post just because he is Euclid but not willing to contribute anything and hide behind excuses. If someone acuses someone else of writing garbage he should proof/explain it. Otherwise I can't take this person seriously. Usually, behavior such as that has some basis in past experience. I don't think anyone has picked on Bucky just because he's Bucky. He's established a reputation. VOLKER LANDWEHR I find it totally okay that someone offers an opinion though he is not sure of all detail or even might have some wrong. And this has been a part of the issue in the past. Bucky offers an opinion which is factually incorrect, then bases further conclusions on that opinion as though it was fact. If called on the mistaken conclusion, "yes, but." And yes, I have cited specifics when countering his mistaken conclusions in the past. Maybe that's why he's a little more thorough these days.
And yes, I have cited specifics when countering his mistaken conclusions in the past. Maybe that's why he's a little more thorough these days.
Oh yeah, and you wish I had established a reputation, since you seem to always be working hard at contributing to it.
And of course you are somehow anointed to be always the one who gets to decide what is factually incorrect.
What you have stated above about me is entirely your made up narrative of generalizations that nobody can verify. How convenient for you. It is nothing but your gossipy personal attack because you just can’t stand the fact that I have the audacity to disagree with you at times. And that is exactly what you express in your childish “yes but” barb. The “but” is the part where I disagree with you and that is just not acceptable in your little world. I think you’d be surprised at how many people can see through what you are up to.
VOLKER LANDWEHRI'm always surprised how easily people pick on Euclid's post just because he is Euclid but not willing to contribute anything and hide behind excuses. If someone acuses someone else of writing garbage he should proof/explain it. Otherwise I can't take this person seriously.
VOLKER LANDWEHRI find it totally okay that someone offers an opinion though he is not sure of all detail or even might have some wrong.
cx500 ..I learnt enough working with experts that I can recognize garbage when I see it. ...
..I learnt enough working with experts that I can recognize garbage when I see it. ...
I would bet your mentors were more patient and kindly disposed toward instruction and enlightenment, and less inclined to harsh ridicule, than you.
I'm always surprised how easily people pick on Euclid's post just because he is Euclid but not willing to contribute anything and hide behind excuses. If someone acuses someone else of writing garbage he should proof/explain it. Otherwise I can't take this person seriously.
I find it totally okay that someone offers an opinion though he is not sure of all detail or even might have some wrong. No better way to learn if others help out. That is one of the reason for discussions
To Euclid's uncertainty: Soil liquefaction needs vibrations.
For all I post a link to the website of the Institute of Geotechnical Engineering at the Technical University Dresden Germany with an explanition what happens inside the soil during liquefaction: https://tu-dresden.de/bu/bauingenieurwesen/geotechnik/forschung/forschungsfelder/bodenverfluessigung?set_language=de
Though there is a link to change to English this is not available. I tried to translate it:
EuclidWhat gives you the idea that I assume that when the phenomenon [liquefaction] occurs, as in quicksand, there is no permanent displacement of the mass of fluidized soil when the load is imposed? I don't know if liquefaction requires vibration, but it seems well documented that vibration can be essential in producing liquefaction. When vibration produces liquefaction, it does result in a shear failure of the soil, but if it were not for the vibration, there would be no liquefaction and thus no shear failure (in at least some cases). So I don't understand why you seem to rule out vibration and replace it with shear failure. I suspect that liquefaction failure at Doon may have developed with the passage of other trains preceding the one that derailed, and if that is so, I would expect that some of the evidence you cite may well have been visible, but went undetected by the inspections.
The most accurate part of the above is "I don't know". Most of us when we don't know prefer not to display our ignorance. Why not go to university and take some soil mechanics and geotechnical courses, and then come back with more intelligent speculation. I learnt enough working with experts that I can recognize garbage when I see it. I could re-enter the conversation but that would only provide more material for you to misuse.
OvermodThe chief difficulty Euclid has with liquefaction is that he assumes that when the phenomenon occurs, as in quicksand, there is no permanent displacement of the mass of fluidized soil when the load is imposed. I think there may be an analogy to what occurs in ballast contamination with fines followed by pumping, where there is a lack of integrity in the subgrade under the track that is masked by a tendency for the track to hold apparent line when unloaded. I would think that recourse to train-generated vibration inducing a state of liquefaction in the subgrade under good ballast is more than a little bit of a stretch; at the very least you'd see signs of incursion of the fluidized subgrade in, probably coating, the ballast, and at least some of the ballast aggregate being forced down and kept after the liquefying vibration had passed off. And yes, I'd think lateral distortion due to 'shear' failure in some plane in the subgrade would be more likely a cause of track-geometry 'compromise' leading to derailment than vertical liquefaction driven by train vibration would be ...
What gives you the idea that I assume that when the phenomenon [liquefaction] occurs, as in quicksand, there is no permanent displacement of the mass of fluidized soil when the load is imposed?
I don't know if liquefaction requires vibration, but it seems well documented that vibration can be essential in producing liquefaction. When vibration produces liquefaction, it does result in a shear failure of the soil, but if it were not for the vibration, there would be no liquefaction and thus no shear failure (in at least some cases). So I don't understand why you seem to rule out vibration and replace it with shear failure.
I suspect that liquefaction failure at Doon may have developed with the passage of other trains preceding the one that derailed, and if that is so, I would expect that some of the evidence you cite may well have been visible, but went undetected by the inspections.
Cotton Belt MP104I am now "bad order" sitting on a siding and watching you professionals highball on the main. over and out
Mike, by the time you got done with that whatever-it-was-you-were-trying-to-establish, even I couldn't figure out what if anything you were trying to say. Except that by back-translating some of those bolded comments you thought it was inappropriate to say that steel was prone to suffer liquefaction, or something.
That's the gist of the criticism, not that professionals are picking on your homespun wisdom somehow. In my opinion some of the metaphors being used are worse than any confusion in the original, and that seems to be one of the points you meant to make, but until I can comprehend your actual arguments better I'm not sure what the issues of concern to you are.
The chief difficulty Euclid has with liquefaction is that he assumes that when the phenomenon occurs, as in quicksand, there is no permanent displacement of the mass of fluidized soil when the load is imposed. I think there may be an analogy to what occurs in ballast contamination with fines followed by pumping, where there is a lack of integrity in the subgrade under the track that is masked by a tendency for the track to hold apparent line when unloaded. I would think that recourse to train-generated vibration inducing a state of liquefaction in the subgrade under good ballast is more than a little bit of a stretch; at the very least you'd see signs of incursion of the fluidized subgrade in, probably coating, the ballast, and at least some of the ballast aggregate being forced down and kept after the liquefying vibration had passed off.
And yes, I'd think lateral distortion due to 'shear' failure in some plane in the subgrade would be more likely a cause of track-geometry 'compromise' leading to derailment than vertical liquefaction driven by train vibration would be ... but that's completely unproven by any available evidence I've seen, and in fact contradicted by the speed with which this derailment appears to have been ameliorated. Which is why I've said little, and continue reticent until better informed.
Overmod I have been holding my tongue about evolving ... discussions ... in this thread. But I draw the line at folks who don't know how to run the quote function and then comment snarkily about what are basically their own misquotes. (Thanks, Volker, for trying to answer it objectively. Hope it does some good.) This is not quite as pathetic as the comments about sourcing the information for "Do You Live In The Blast Zone", but you can see it from there. C'mon guys, you can have a better level of discourse, even if you still have trouble spelling 'liquefaction' after all these posts.
I have been holding my tongue about evolving ... discussions ... in this thread. But I draw the line at folks who don't know how to run the quote function and then comment snarkily about what are basically their own misquotes. (Thanks, Volker, for trying to answer it objectively. Hope it does some good.)
This is not quite as pathetic as the comments about sourcing the information for "Do You Live In The Blast Zone", but you can see it from there.
C'mon guys, you can have a better level of discourse, even if you still have trouble spelling 'liquefaction' after all these posts.
You professional posters win. This is not the first time my novice ways have been offensive. Sorry for the angst caused.
I am now "bad order" sitting on a siding and watching you professionals highball on the main. over and out mike endmrw0725181323
OvermodC'mon guys.......... you still have trouble spelling 'liquefaction' after all these posts.
Thanks to Chris / CopCarSS for my avatar.
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