Toronto Ontario Line 3 | ?m | ?s

Maybe the tunnelling shouldn't be done under the street, but deep under buildings away from the streets. The boring tunnels will be under the buildings at the curves, but currently the straight tunnels would be under the streets. Since the stations and emergency exits is where most of the disruption occurs, maybe the stations should be built away from the intersections, like they were done with Line 2?
 
W. K. Lis said:
Maybe the tunnelling shouldn't be done under the street, but deep under buildings away from the streets. The boring tunnels will be under the buildings at the curves, but currently the straight tunnels would be under the streets. Since the stations and emergency exits is where most of the disruption occurs, maybe the stations should be built away from the intersections, like they were done with Line 2?
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This is indeed something that was considered for the relief line project. There is considerably more liability due to surface movements on private buildings and residences than on public infrastructure (such as roads). However, one might expect there to be less surface movement when boring through rock than through soil, which would make any sections through rock an ideal place to shift the alignment from the road to allow for stations to be built with less traffic impacts. It would be a less attractive option in areas where the alignment would plan to be in soils. Does this mean depth should be increased to reach rock?

Do consider that increasing the depth by a small amount (say, 10m) may not seem like a big deal for the running tunnels, but station excavation becomes exceedingly expensive at great depths. This is especially true when excavating in rock as Toronto's shale has a high horizontal stress regime and expands. Station cavern design can be quite difficult in areas where the horizontal stresses are larger than the vertical stresses, in comparison to the relatively simple stress regimes of soils.

You have to carefully balance:
1) Surface impacts due to displacement of the soil and rock due to excavation (impacts to utilities, public and private buildings, rail, etc)
This is usually worse in soil and better in rock.
2) Depth of running tunnels, and therefore shaft/station depth.
Increasing the depth may reduce surface impact but will increase cost.
 
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Reecemartin said:
The difference is Montreal's REM is getting them (testing has begun on the doors and the infrastructure is being built so that they can be installed). Toronto surely won't be devoid of them when the folks in Montreal have already got a taste. I'm sure the Unions would fight on it too.
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Toronto's problem isn't really door related; is the platform asbestos and ventilation systems (smoke removal in most stations relies on the stairwells for airflow) that are the challenge.

AFAIK, only Finch station had the ventilation system upgraded (2010); and it was about 10x the hoped for price (the price the board was expecting before assigning engineering to actually design it). Platform doors for all TTC stations is a $2.5B project; about $2B is not really door related.

That said, I hope they're included in the $1B Bloor-Yonge remodel.
 
rbt said:
as

Toronto's problem isn't really door related; is the platform asbestos and ventilation systems (smoke removal in most stations relies on the stairwells for airflow) that are the challenge.

AFAIK, only Finch station had the ventilation system upgraded (2010); and it was about 10x the hoped for price (the price the board was expecting before assigning engineering to actually design it). Platform doors for all TTC stations is a $2.5B project; about $2B is not really door related.

That said, I hope they're included in the $1B Bloor-Yonge remodel.
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That's about the pricing for the STM and there's less issues with the ventilation as most of it is done through ventilation substations and not the stations themselves. Line 2 preliminary cost estimates are about 1G$. Line 5 costings are being done, new stations on that line should have them from the opening date in 2026.
 
Reecemartin said:
The TTC is not packed even at 7:30. Sure it's not empty but yeah you can get a seat on outer subway stations at that time. At 6:30 it's not busy.
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I don't know where the hell you are getting on the subway at, but at a little after 7am every southbound train at Eglinton is leaving people behind.

Dan
 
^Heck you dont even have to look as far as the Yonge Line, even at 7am eastbound trains to Bloor-Yonge are pretty damn busy after they hit Islington. I'll even go as far to say that the very first train eastbound on the Bloor-Danforth line is packed by the time it reaches Bloor-Yonge.

Westbound is a similar story from Victoria Park onwards.
 
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