RyLucky
Active Member
Can anyone comment further on the single vs double bore? I don't think I've ever been in a vertically stacked single bore metro station.
Green Line LRT | ?m | ?s | Calgary Transit
- Thread starter Surrealplaces
- Start date
I would prefer the side by side version all things equal. I don't recall any subway systems anywhere that have the two lines stacked upon each other.
darwink
Senior Member
Apparently Barcelona Metro Line 9. A primer here: http://www.cat-bus.com/2017/10/barcelonas-line-9-inspiring-montreals-pink-line/
zagox
Active Member
Vancouver's Expo line uses this configuration downtown, although the tunnel was not originally designed for this purpose. Seems to work fine.
From https://en.wikipedia.org/wiki/Dunsmuir_Tunnel: Because the tunnel is only wide enough to accommodate a single railway track but with sufficiently high clearance, a superstructure was built inside the tunnel to carry the westbound SkyTrain track above the eastbound track. This results in the two stations within the tunnel having a split platform configuration."
Social Justice
Active Member
"Giannelia said the project team has concluded that a single-bore tunnel would be the most cost-effective and user-friendly design for the route."
I say do it if it's cheaper.
I say do it if it's cheaper.
Looking at the space in the tube, it definitely is more efficient space-wise to go with the up/down config.
BKha
Active Member
IIRC some of the stations in Hong Kong's metro are on top of each other.
Stephen Ave
Active Member
If it's cheaper and can do the same thing why not right? Also, having the platforms above each other might be easier for building the passenger entrance/exit, as they would only need to be on one side of the station.
Myles86
Active Member
That is correct, notably Island Line stations around the Causeway Bay area.
darwink
Senior Member
Yeah. Not sure how the trade off would work re:cpted. I imagine each deep station would need a near permanent presence by special constables, with long spiral ramps or staircases and platforms that clear on every train movement. With a dual platform on the same level, you would almost always have some people waiting for the train, with clear visibility to both of the platforms, providing ‘eyes on the street’.
AJX
Active Member
My preference would be to have the two platforms across from each other, but it's depends on the cost savings. Maybe there's a way to make the the platforms on top of each other but have a double height area that's open to both platforms?
MichaelC
Active Member
So would they have to close the whole tunnel if they had to do maintenance? In a regular LRT/Subway tunnel when they work on one of the tracks, the trains go around on the other track, but I assume that the trains wouldn't be able to switch tracks with a single bore tunnel?
That's a good question. I was wondering the same thing myself. I imagine it would be more difficult to switch trains onto another track with the single bore.
darwink
Senior Member
Nah, it works just fine. just think of where the tracks are as two single bore tunnels on top of each other, then weave them to be side by side and back. No more difficult than mining out a crossover box for a dual bore.
Stephen Ave
Active Member
That makes sense. If there are no platforms involved, the two tracks can go side by side in a single bore tunnel, so having a switchover point somewhere isn't a big deal.