Broadway Subway - Millennium Line Extension to Arbutus (II) | U/C

[idunno]

Such high ceilings in the lower part of that transition box. I wonder if they'll keep em high - would be a cool view coming into the tunnel.

[SFUVancouver]

The large tunnel portal volume should help reduce/avoid the air-piston effect of trains entering and exiting the tunnel.

[jollyburger]

Originally Posted by idunno

Such high ceilings in the lower part of that transition box. I wonder if they'll keep em high - would be a cool view coming into the tunnel.

The transition box is symmetrical so it drops back down to a similar profile. You can see it on the Google Maps "satellite" view of the site.

[officedweller]

Nice pic.
You can even see the superelevation of the trackbed (i.e. banking for the curve).
I'm thinking only one track bed has been poured so far.

[jollyburger]

Originally Posted by officedweller

Nice pic.
You can even see the superelevation of the trackbed (i.e. banking for the curve).
I'm thinking only one track bed has been poured so far.

I think there's only one trackbed on each side of the internal wall of the transition box. If it's that wide for one train I wonder if that's the reason the ceilings are so high. The temporary road seems like it was built exactly where that section of the box was elevated.



https://x.com/broadwaysubway_/status...675901/photo/1

[officedweller]

Oh, I thought that was a 2-way tunnel.
Maybe the raised part is the safety walkway, as it's narrower than the lower side.

[jollyburger]

Originally Posted by officedweller

Oh, I thought that was a 2-way tunnel.
Maybe the raised part is the safety walkway, as it's narrower than the lower side.

But from this it sounds like that raised bit is for the track. I think we're looking into the station since the doorway on the left might indicate the emergency connection to the other side? It would match up with the track on the outer section of the elevated guideway.

Crews have completed the concrete base to allow for the track installation. This final layer, called the track slab, will have tracks installed on top of it.

[Vantage]

Originally Posted by officedweller

Nice pic.
You can even see the superelevation of the trackbed (i.e. banking for the curve).
I'm thinking only one track bed has been poured so far.

As per the tour I had last month, the other track bed is poured as well and is on the other side of the wall, they do not share the same tunnel.

[officedweller]

Originally Posted by jollyburger

But from this it sounds like that raised bit is for the track. I think we're looking into the station since the doorway on the left might indicate the emergency connection to the other side? It would match up with the track on the outer section of the elevated guideway.

Could be the lens / angle that makes the elevated part look narrower.

[jollyburger]

For scale some people and the track section.

(April 29, 2024) Preparing Tunnel Section for a Concrete Pour by B.C. Ministry of Transportation and Infrastructure, on Flickr