Re:Four ways to speed up trains on the New Silk Road (2020)
by iggldiggl on Tuesday April 06, 2021 @02:05AM
(#26708451)
Fair enough about the eastern part, but as you say we're lacking something comparable to the western half as a starting point. I'd been sort of implicitly averaging the two halves together for the US.
Regarding electrification, yes, it's not rocket science, and the cost of raising bridges and tunnel clearances will usually dominate, but because electrification on the main lines covers basically every metre, I'd think that the costs would still add up significantly.
Re:Four ways to speed up trains on the New Silk Road (2020)
by sjsamson on Wednesday April 07, 2021 @05:13AM
(#26722168)
There are overhead electric rail lines supporting double stack freight in the NEC USA, China, India, and possibly elsewhere. There are YouTube videos and images on web. AAR Plate H (20’ 2”) is the North American rail loading gauge for double stack containers, so 21’-23’ for the electrical lines is enough clearance. Nothing unusual here, straight forward for new lines, but as you noted potentially a lot work/cost on existing lines to create enough clearance due to raising overpasses/structures and/or undercutting them and tunnels.
Re:Four ways to speed up trains on the New Silk Road (2020)
by Animats on Sunday April 18, 2021 @02:16AM
(#26850232)
That's tight. Here's a document from Network Rail on the practical problems of trying to increase the loading gauge in the UK so containers can fit on electrified lines.[1] That's just to make room for single height containers. In the UK, the catenary clearance is sometimes reduced to get under historic bridges, but that requires slowing trains way down.
Sometimes the rail bed is lowered, but that creates drainage problems. Raising historic masonry bridges is even harder. This document has good pictures of all the problems.
[1] https://www.bathnes.gov.uk/sites/default/files/sitedocuments...
Probably the big differences are that a) the US already had a comparatively roomy loading gauge compared to Europe before conversion was necessary and b) the West Coast-to-Midwest routes were probably more likely to be double-stack-compatible before the projects started and provided a seed route to develop the concept before the expensive loading gauge conversions in the east had to take place.
Electrification doesn't affect double-stacked routes other than needing (I think) an extra ~2 ft of height compared to non-electrified track. The cost of relaying catenary cables isn't going to be all that high: electrifying track from scratch in the first place appears to cost about $1 million per km, and a lot of that cost will include the substations which don't need to be replaced; actual costs of replacing the gantries is likely to be less than half that. That's of course assuming that there is actually room above the track to support the new height.