Railroad Forums 

  • Vertical Double Tracking

  • General discussion about railroad operations, related facilities, maps, and other resources.
General discussion about railroad operations, related facilities, maps, and other resources.

Moderator: Robert Paniagua

 #647610  by gprimr1
 
I was traveling through the Tehachapi Mountains, (in CA but not for a good reason) and I got to thinking, has anyone ever explored if it would be fiesable to build a second track elevated on top of the first track? With the mountains, there probably would be solid rock to anchor onto and the grade wouldn't really be any steeper than the track that's already there. I don't know if anyone has ever considered if it's possible or cost effective for double tracking in areas were it might be otherwise very difficult.
 #647617  by 130MM
 
gprimr1 wrote:I was traveling through the Tehachapi Mountains, (in CA but not for a good reason) and I got to thinking, has anyone ever explored if it would be fiesable to build a second track elevated on top of the first track? With the mountains, there probably would be solid rock to anchor onto and the grade wouldn't really be any steeper than the track that's already there. I don't know if anyone has ever considered if it's possible or cost effective for double tracking in areas were it might be otherwise very difficult.
Continuous bridging would be extremly expensive. Not to mention what do you do at tunnels?

DAW
 #647665  by 2nd trick op
 
I'm fairly sure that a longer tunnel at a lower altitude would be a more cost-effective solution. Let's remember that the Cascade Tunnel had a two-mile predecessor, and that Espee and Kaiser Engineering did a serious study involving nearly forty miles of tunnelling under Donner Summit in the late 1940's.

Probably the greatest roadblock in the way of major improvements to our rail infrastructure in coming years will be funding, possibly aggravated by political instability. The remaining major freight railroads represent huge amounts of immovable physical capital, and the continued decline of our automobile industry is painful testimony of what can happen when a group of special interests, each one with a different agenda, scramble for the imagined "right" to call the shots.

UP has some very good reasons for its "bunker mentality", given the likelihood of a continued severe economic downturn and a substantial portion of the electorate remaining economically gullible and hungry for a quick fix.
Last edited by 2nd trick op on Mon Mar 16, 2009 7:00 am, edited 3 times in total.
 #649834  by David Benton
 
Great article there SL Club .
Rather than been on top of one another , i think that having the tracks on different levels side by side on a steep slope would be the answer . we would call it benching , it would require a smaller cut , and would be naturally more stable , s it follows the contour of the mountain side more . this could also have the benefit of providing different gradients for different normal directions of travel if desired .
As to tunnels , i cant think of any that are double deck , they always seem to be side by side .