4 ms·

This is true, but the camber you can use is limited by the fact that you may have to stop the train on the curve without it falling over.

anticensor 7y ago
You could implement a strategy of allowing evacuations only at scheduled stops.
- innocenat 7y ago
  Doesn't work if the train caught fire or something.
- netsharc 7y ago
  But if the track is distrupted (a tree falls on it, or somehow it's just damaged), the train would have to stop right there and then. Maybe they can make something so the train can grip the ground/tracks so it just doesn't fall off when the forces are no longer acting on it.
  - majewsky 7y ago
    The tracks are not fixed to the ground. If a train grips the tracks in order not to fall over, it will probably still fall over and also rip the tracks out of the railbed as it does so.
    - netsharc 7y ago
      True, as we've learned in this article. I guess it will have to grip to something else. But in the theoretical banking the original comment was talking about (let's say 30 degrees), the track would probably have to be secured to the surface... Well, how heavy is a bullet train, where is its center of gravity, and how much banking does it need if it wants to travel, say, 300 km/h in a (how sharp?) a curve?
      - bobthepanda 7y ago
        Keep in mind that banking is only comfortable if you are traveling at the correct speed. There are a whole host of reasons why a train may not travel at maximum speed for a given segment, and the rail line still needs to be reasonably comfortable at all of those.
    - m4rtink 7y ago
      This is not always true, most of Shinkansen track is concrete slab track, which is effectively fixed to the ground. And they actually do have special anti derailment guides build into the track to prevent a train from derailing during an earthquake: https://www.rtri.or.jp/eng/rd/seika/2006/01/safety_E05.html https://www.rtri.or.jp/eng/rd/seika/2006/01/safety_E05.html
Cthulhu_ 7y ago
There is / was a train design where the train itself could lean into corners on a flat (legacy) train track. Pretty sure that's not considered anymore because the tilting system adds a lot of weight and complexity. Mag-lev trains seem to reach 'around' the tracks, so that could work. Of course if the levitation stops in a corner (or anywhere, really) on that one it'll cause major damage.
- jaclaz 7y ago
  >There is / was a train design ... Pendolino: https://en.wikipedia.org/wiki/Pendolino https://en.wikipedia.org/wiki/Pendolino Up to 8-10° , i.e. 1.35 m/s^2 compensation https://it.wikipedia.org/wiki/Pendolino#Caratteristiche_generali https://it.wikipedia.org/wiki/Pendolino#Caratteristiche_gene...
- m4rtink 7y ago
  Tilting trains are actually in wide use, see: https://en.m.wikipedia.org/wiki/Tilting_train https://en.m.wikipedia.org/wiki/Tilting_train Even the lates shinkansen transets do it to reach higher speed, especially on older parts of the track with sharper turns: https://en.m.wikipedia.org/wiki/N700_Series_Shinkansen https://en.m.wikipedia.org/wiki/N700_Series_Shinkansen

anticensor 7y ago

You could implement a strategy of allowing evacuations only at scheduled stops.

innocenat 7y ago
Doesn't work if the train caught fire or something.
netsharc 7y ago
But if the track is distrupted (a tree falls on it, or somehow it's just damaged), the train would have to stop right there and then. Maybe they can make something so the train can grip the ground/tracks so it just doesn't fall off when the forces are no longer acting on it.
- majewsky 7y ago
  The tracks are not fixed to the ground. If a train grips the tracks in order not to fall over, it will probably still fall over and also rip the tracks out of the railbed as it does so.
  - netsharc 7y ago
    True, as we've learned in this article. I guess it will have to grip to something else. But in the theoretical banking the original comment was talking about (let's say 30 degrees), the track would probably have to be secured to the surface... Well, how heavy is a bullet train, where is its center of gravity, and how much banking does it need if it wants to travel, say, 300 km/h in a (how sharp?) a curve?
    - bobthepanda 7y ago
      Keep in mind that banking is only comfortable if you are traveling at the correct speed. There are a whole host of reasons why a train may not travel at maximum speed for a given segment, and the rail line still needs to be reasonably comfortable at all of those.
  - m4rtink 7y ago
    This is not always true, most of Shinkansen track is concrete slab track, which is effectively fixed to the ground. And they actually do have special anti derailment guides build into the track to prevent a train from derailing during an earthquake: https://www.rtri.or.jp/eng/rd/seika/2006/01/safety_E05.html https://www.rtri.or.jp/eng/rd/seika/2006/01/safety_E05.html

Cthulhu_ 7y ago

There is / was a train design where the train itself could lean into corners on a flat (legacy) train track. Pretty sure that's not considered anymore because the tilting system adds a lot of weight and complexity. Mag-lev trains seem to reach 'around' the tracks, so that could work. Of course if the levitation stops in a corner (or anywhere, really) on that one it'll cause major damage.

jaclaz 7y ago
>There is / was a train design ... Pendolino: https://en.wikipedia.org/wiki/Pendolino https://en.wikipedia.org/wiki/Pendolino Up to 8-10° , i.e. 1.35 m/s^2 compensation https://it.wikipedia.org/wiki/Pendolino#Caratteristiche_generali https://it.wikipedia.org/wiki/Pendolino#Caratteristiche_gene...
m4rtink 7y ago
Tilting trains are actually in wide use, see: https://en.m.wikipedia.org/wiki/Tilting_train https://en.m.wikipedia.org/wiki/Tilting_train Even the lates shinkansen transets do it to reach higher speed, especially on older parts of the track with sharper turns: https://en.m.wikipedia.org/wiki/N700_Series_Shinkansen https://en.m.wikipedia.org/wiki/N700_Series_Shinkansen