charlie hebdoIt is a threadbare strategy used by those members whose knee-jerk reaction to anything Euclid posts is animosity. Their desire is to flood the thread with inanity so that it gets locked. Is Euclid irritatingly obsessive, at times even arguing with himself? Sure. But he also seeks answers to questions that make some folks uncomfortable. And if all this were about was their irritation or boredom with his "yes, buts" they could simply ignore the thread or not respond to him. But it has a far more nasty goal - censorship.
I know and agree.Regards, Volker
cx500 Murphy Siding Are you a soil engineer? He very obviously isn't, to anybody who has had any even casual experience with their impact on the railroad. However in his quoted link the phrase "have produced some confusion in usage and understanding" seems very fitting.
Murphy Siding Are you a soil engineer?
He very obviously isn't, to anybody who has had any even casual experience with their impact on the railroad. However in his quoted link the phrase "have produced some confusion in usage and understanding" seems very fitting.
No need to be a soil mechanics and geotechnical engineer in view of the literature aimed to laymen. They are good enough to understandably describe the causes.
I, as a civil engineer (structural design) haven't seen anything wrong in Euclid's description. Soil liquefaction is one propable cause of the derailment. Others were mentioned in this thread.
The linked article explains the cause and its possible consequences. The quoted part refers to the inaccurate use of the terms, mixing up cause and consequences.Regards, Volker
VOLKER LANDWEHR For Yes, But you always need more than person. On side usually is one person, the other side a few. And a number of those are so preoccupied that they wouldn't admit or realize a good information or correct answer. If you want to end it, why not stop answering?Regards, VolkerRegards, Volker
For Yes, But you always need more than person. On side usually is one person, the other side a few. And a number of those are so preoccupied that they wouldn't admit or realize a good information or correct answer.
If you want to end it, why not stop answering?Regards, VolkerRegards, Volker
It is a threadbare strategy used by those members whose knee-jerk reaction to anything Euclid posts is animosity. Their desire is to flood the thread with inanity so that it gets locked. Is Euclid irritatingly obsessive, at times even arguing with himself? Sure. But he also seeks answers to questions that make some folks uncomfortable. And if all this were about was their irritation or boredom with his "yes, buts" they could simply ignore the thread or not respond to him. But it has a far more nasty goal - censorship.
Yes, but!
Never too old to have a happy childhood!
tree68 charlie hebdo And the rest of us can read and learn something, maybe. You may see it as providing more information - some see it as an attempt to cover all of the bases so if a cause is made public Bucky can say "see, I told you so!"
charlie hebdo And the rest of us can read and learn something, maybe.
You may see it as providing more information - some see it as an attempt to cover all of the bases so if a cause is made public Bucky can say "see, I told you so!"
charlie hebdoAnd the rest of us can read and learn something, maybe.
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...
Murphy SidingAre you a soil engineer?
I don't believe that I have made any claims that require me to be a soil engineer (which I am not). I'm just touching the basics here, and you don't need to be a soil engineer to understand my points. I thought the quote from the link raised an interesting and pertinent point about the confusion over liquefaction and its consequences. That is why I directed it to Dave. I tried to put it into non-soil engineering terms for all the non-soil engineers out there. Are you a soil engineer?
As I recall, the PDF makes a distinction in which liquefaction is not ground movement even though it is often cited in cases of severe ground movement such as in earthquakes. What liquefaction does is make ground movement possible. I believe that this is the basic point of the quote citing some confusion about liquefaction and its consequenses. By the way, are you a soil engineer? Do you know a lot of soil engineers?
Murphy Siding Euclid: Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.” Are you a soil engineer?
Euclid: Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.” Are you a soil engineer?
Euclid dehusman Euclid If the slope failed during the passage of the train, I would call that liquefaction, which is the type of failure that I believe occurred. Liquifaction is one thing, a slope failure is another. Liquifaction the material in the fill changes from behaving like a solid to behaving like a liquid and flows. Slope failure the structure of the slope "mechanically" fails and the slope shifts. I assume that slope failure can occur without liquefaction, but references say that it can also be caused by liquefaction. In most cases, it is the weight of the soil and effect of gravity that causes ground movement when liquefaction occurs. With railroads, it is the weight of the soil, the effect of gravity, and the loading of the train that causes ground movement when liquefaction occurs. The train also provides the ground shaking that triggers saturated soil to achieve liquefaction. I believe the Doon derailment was caused by liquefaction of the roadbed fill which had become saturated by the high water. Then the soil was subjected to the loading of the train, and at the same time, it was also shaken by the train. Then the shaking triggered liquefaction to cause a sudden loss of support. Maybe the slope was involved in this collapse of soil support, or maybe not. The fill is relatively narrow, so it could have failed across its entire width. Here is a reference to liquefaction and ground movement including slope failure: https://pubs.usgs.gov/circ/1973/0688/report.pdf From the link: “Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.”
dehusman Euclid If the slope failed during the passage of the train, I would call that liquefaction, which is the type of failure that I believe occurred. Liquifaction is one thing, a slope failure is another. Liquifaction the material in the fill changes from behaving like a solid to behaving like a liquid and flows. Slope failure the structure of the slope "mechanically" fails and the slope shifts.
Euclid If the slope failed during the passage of the train, I would call that liquefaction, which is the type of failure that I believe occurred.
Liquifaction is one thing, a slope failure is another. Liquifaction the material in the fill changes from behaving like a solid to behaving like a liquid and flows. Slope failure the structure of the slope "mechanically" fails and the slope shifts.
I assume that slope failure can occur without liquefaction, but references say that it can also be caused by liquefaction. In most cases, it is the weight of the soil and effect of gravity that causes ground movement when liquefaction occurs. With railroads, it is the weight of the soil, the effect of gravity, and the loading of the train that causes ground movement when liquefaction occurs. The train also provides the ground shaking that triggers saturated soil to achieve liquefaction.
I believe the Doon derailment was caused by liquefaction of the roadbed fill which had become saturated by the high water. Then the soil was subjected to the loading of the train, and at the same time, it was also shaken by the train. Then the shaking triggered liquefaction to cause a sudden loss of support. Maybe the slope was involved in this collapse of soil support, or maybe not. The fill is relatively narrow, so it could have failed across its entire width.
Here is a reference to liquefaction and ground movement including slope failure:
https://pubs.usgs.gov/circ/1973/0688/report.pdf
From the link:
“Because of the critical effect liquefaction has on the safe performance of engineered construction and the stability of certain geologic formations, considerable study has been devoted to this topic in recent years. Significant progress has been made in understanding the liquefaction phenomenon and the factors controlling it; however, ambiguity in present definitions of the term liquefaction and lack of clear distinction between liquefaction and ground-failure conditions associated with this phenomenon have produced some confusion in usage and understanding of liquefaction and its consequences.”
Thanks to Chris / CopCarSS for my avatar.
dehusman Wow, Bucky's so determinded to have the last word that he is moving his posts around.
Wow, Bucky's so determinded to have the last word that he is moving his posts around.
Yes, but...
EuclidIf the slope failed during the passage of the train, I would call that liquefaction, which is the type of failure that I believe occurred.
Dave H. Painted side goes up. My website : wnbranch.com
dehusman .... or most likely, none of the above, #4 a plain old slope failure.
.... or most likely, none of the above, #4 a plain old slope failure.
Do you mean a failure of the fill bank slope while submerged in flood water? I suppose that is possible to have occurred before the train arrived without being seen by the constant track inspections during the flood.
However, if it did happen before the arrival of the train, it seems most likely that it would have derailed the head end of the train as soon as it encountered the unsupported track. But that did not happen.
If the slope failed during the passage of the train, I would call that liquefaction, which is the type of failure that I believe occurred.
I can see three different types of flood-related defects that may have caused the derailment:
Soil erosion on the surface around the track structure.
Soil erosion inside of the fill bank supporting the track structure.
Soil liquefaction inside of the fill bank supporting the track structure.
I would say that the least likely is #1 and most likely is #3. All three causes could allow an entire train to pass without causing a derailment; or allow part of the train to pass before passage of the train accentuates the water-caused defect sufficiently to derail the train. All three causes could also derail the train just as the locomotive encounters the defect.
Cause #1 would be spotted by all of the monitoring and inspections under way as we have been told always happens. That is why I believe that #1 is the least likely. Cause #2 could produce an effect similar to cause #3. Both could lead to a collapse of the roadbed.
One difference is that #2 could collapse the roadbed without a train passing over it, and thus be found by inspection like cause #1. Whereas cause #3 would not collapse the roadbed unless a train were passing over it. So cause #3 would not be detected by any inspection.
Also, of the three causes, #3 is the least likely to derail the head end because the liquefaction site has to be developed by the train passage. With liquefaction, the train shakes the soil over enough time to produce the soil condition that derails the train. So it will be unlikely to derail the train until after the head end has passed the saturated soil site where liquefaction can be triggered.
.
Just because Acting Governor Reynolds* says something in her proclamation doesn't mean it's gospel.
*She was elected Lt. Governor of Iowa. The Iowa Constitution says the Lt. Governor takes on the duties and responsibility of the office of Governor when the Governor can't finish out the term. It does not say that they are elevated to the actual position of governor. (Former Governor Branstad resigned to become ambassador to China.) I am in this camp, that she is still actually the Lt. Governor discharging the duties of Governor.
Jeff
Before you get too excited.
Liquification is a very specific thing. There are numerous other types of failures that could have happened, that could have been accelerated by the rain, that could have been triggered by loading as well as vibration, other than liquification.
We still don't know what the actual cause of the subgrade failure was.
blue streak 1That vibration by earthquakes is exactly what happens to cause the liquefaction damages that are so destructive on fill and settlement soils.
Earthquakes are one probable cause for soil liquefaction. Other vibrations, like heavy trains, can have the same effect. https://www.youtube.com/watch?v=Rd6W2aP2dkA
Wiki explanation "Soil liquefaction": Soil liquefaction occurs when a saturated or partially saturated soil substantially loses strength and stiffness in response to an applied stress such as shaking during an earthquake or other sudden change in stress condition, in which material that is ordinarily a solid behaves like a liquid.
Regards, Volker
Euclid This is because the final key to a liquefaction failure is vibration of the soil, and that is provided by the train passage.
That vibration by earthquakes is exactly what happens to cause the liquefaction damages that are so destructive on fill and settlement soils.
Cotton Belt MP104If there was such horrible damage due to the flooding issue, which has been documented and discussed in GREAT detail (btw..... that's why I started this thread) ......... how come they got back to operating so quickly, without delay due to all the work that would be needed to repair ROW undermined by flooding?
If the roadbed fill had been undermined, it would not necessarily have occurred over the entire length of the fill. It may have just been confined to the area where the derailment occurred. Regardless of whether undermining occurred there, that spot would have needed a lot of earthwork repair just due to being dug up by the pileup of cars.
Also, if an area were undermined to the point where it would derail the train, there would be a high probability that the locomotives would have derailed when they hit that weak spot.
With liquefaction, there is no undermining or removal of supporting soil. Instead, the soil remains in place, but loses its ability to carry a load. And it does not lose the supporting ability prior to the arrival of a train. Instead, it develops its loss of support as the train passes. This is because the final key to a liquefaction failure is vibration of the soil, and that is provided by the train passage.
zardoz Round and round we go.....
Round and round we go.....
Johnny
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