Toronto Crosstown LRT | ?m | ?s | Metrolinx | Arcadis

[BurlOak]

They should have done cut and cover! This is ridiculous. Cut and Cover would have save 5 years and maybe this is up and running in 2018! Same with the DRL. Hell cut and cover would all us to do all the Transit projects faster.

I am not sure, but I think the decision to use TBM was before they realized that boring could not be done under the existing subway lines. Essentially, these are 3 separate boring jobs each about 3 km long (the East one is a bit longer now that the launch site was moved to Don Mills). In those 3 kilometres, there are 3 or 4 stations (each with probably about a 200m cut excavation), plus a launch and extraction site. This means that even though TBM is used, about 1/3 of the total length is actually built with cut-and-cover. (If the station spacing on the DRL are closer, this could become over half).

I wonder why this is being built P3. Design–bid–build (design–tender) would require all design work for each step to be done before award. Design-Build could shorten the construction time a bit by only having preliminary design completed prior to tender, but the construction risk may be a bit higher. P3 (or AFP) is best suited for the entire process. There are a lot more risks for an "operate" contract so the Contractor needs to have enough flexibility to implement some inovative techniques to save enough money to compensate for the risks. I would have thought a real P3 contract would allow the contractor to propose different construction methods within certain contract constraints. It looks like they are using a combination of tendering methods and P3 is specified just to say it is being used, but not to actually try saving money or getting a better product.

 

[sixrings]

went for a jog today and noticed they have taken down the trees in front of the police station at allen road and 1069 eglinton avenue west. I always thought that 1069 could make for some good land for a higher 8 floor condo with retail to appear. However I always thought the trees wouldn't help that. I am extremely sad to see the Trees gone however if this opens up possibilities for some redevelopment I might be OK with it... these were some good sized trees BTW.

 

[Rainforest]

Ferrand is too close to Don Mills and shoehorning the tunnel portal between the two stations means that there is no room for tail tracks east of Don Mills, which would make short turning easier to manage.

The detailed design of the Don Mills station and adjacent line segments is not available yet. They might be able to keep the tail track (east of Don Mills) underground, while the two main revenue tracks ascend to the surface level before the Ferrand stop.

Given that the Eglinton line is designed for 90-m trains at most, they will need something like 120 m of extra tunnel; or even less if the western half of tail track is located in the section that will be tunneled anyway.

 

[nfitz]

I am not sure, but I think the decision to use TBM was before they realized that boring could not be done under the existing subway lines. Essentially, these are 3 separate boring jobs each about 3 km long (the East one is a bit longer now that the launch site was moved to Don Mills). In those 3 kilometres, there are 3 or 4 stations (each with probably about a 200m cut excavation), plus a launch and extraction site. This means that even though TBM is used, about 1/3 of the total length is actually built with cut-and-cover. (If the station spacing on the DRL are closer, this could become over half).

There are no launch and extraction sites at each station. The tunnel is built first, and then the station is built after, except for Eglinton and Eglinton West, where this is extraction and launch sites. They were fully aware that they couldn't bore under the subway lines.

The TBM tunnelling is only about $50 million per km of twin-tunnel. It's had to imagine that cut-and-cover would be that cheap, especially given the topography, depth, and soils involved.

 

[innsertnamehere]

important to note that the Eglinton crosstown will be built much differently than the Spadina extension. the TBM's will bore through each station with only the shoring having being performed, and full excavation for each stop will be performed only when the tunnel borer is long gone. They will dig down to the existing Tunnel Bore, and remove the Concrete liner to create the station.

 

[andrewpmk]

The detailed design of the Don Mills station and adjacent line segments is not available yet. They might be able to keep the tail track (east of Don Mills) underground, while the two main revenue tracks ascend to the surface level before the Ferrand stop.

Given that the Eglinton line is designed for 90-m trains at most, they will need something like 120 m of extra tunnel; or even less if the western half of tail track is located in the section that will be tunneled anyway.

Why would you want to have such a complex design like that, rather than just eliminating the rather useless Ferrand stop? Plus if the downtown relief line goes to Don Mills/Eglinton, you need provision for that in the design, which makes the design of the station even more complicated.

 

[Platform 27]

I am not sure, but I think the decision to use TBM was before they realized that boring could not be done under the existing subway lines. Essentially, these are 3 separate boring jobs each about 3 km long (the East one is a bit longer now that the launch site was moved to Don Mills). In those 3 kilometres, there are 3 or 4 stations (each with probably about a 200m cut excavation), plus a launch and extraction site. This means that even though TBM is used, about 1/3 of the total length is actually built with cut-and-cover. (If the station spacing on the DRL are closer, this could become over half).

Eglinton's tunnels are considerably deeper on average than most other lines on the subway (look at the stairs on Caledonia station's secondary entrance for one example of how this line has shades of the London Tube). I don't think there was much of an opportunity to go shallower because train climbing grades can't keep up with the hilliness of Eglinton itself. Even if the community disruption issue was a non-factor (and we know it very much isn't), I'm willing to guess the depth of the trench that would need to be excavated probably wipes out any cost-savings of a bore.

 

[BurlOak]

Eglinton's tunnels are considerably deeper on average than most other lines on the subway (look at the stairs on Caledonia station's secondary entrance for one example of how this line has shades of the London Tube). I don't think there was much of an opportunity to go shallower because train climbing grades can't keep up with the hilliness of Eglinton itself. Even if the community disruption issue was a non-factor (and we know it very much isn't), I'm willing to guess the depth of the trench that would need to be excavated probably wipes out any cost-savings of a bore.

I thought LRT can handle a 5% slope. I would guess that the grade on Eglinton is never more than 5% - it is shown as 4.9% for the hill just east of Brentcliffe. The LRT (or Skytrain, but not HRT subway) could probably have just followed the road profile - about 8 to 10m down. Maybe they just wanted to smooth out the line for passenger comfort - but then the latest revision to go under the Don River West Branch adds extra undulation.

 

[junctionist]

I thought LRT can handle a 5% slope. I would guess that the grade on Eglinton is never more than 5% - it is shown as 4.9% for the hill just east of Brentcliffe. The LRT (or Skytrain, but not HRT subway) could probably have just followed the road profile - about 8 to 10m down. Maybe they just wanted to smooth out the line for passenger comfort - but then the latest revision to go under the Don River West Branch adds extra undulation.

Subway technology can handle grades of more than 5 percent, but it has to be rubber tired. The Montreal Metro trains can handle grades of 6 percent according to John Martins-Manteiga in his book Metro: Design in Motion.

 

[W. K. Lis]

I thought LRT can handle a 5% slope. I would guess that the grade on Eglinton is never more than 5% - it is shown as 4.9% for the hill just east of Brentcliffe. The LRT (or Skytrain, but not HRT subway) could probably have just followed the road profile - about 8 to 10m down. Maybe they just wanted to smooth out the line for passenger comfort - but then the latest revision to go under the Don River West Branch adds extra undulation.

There are hills on Eglinton that are over 5%, which is the limit for the light rail vehicles. The streetcars are supposed to be able to handle 8% inclines, but not the light rail vehicles for the Transit City lines. From Keele east to Caledonia, the tunnel inclines will have to be no more than 5%, which is why the station at Caledonia is very deep, but the station at Keele is shallow, the tunnels cannot exceed 5% incline.

 

[Rainforest]

Why would you want to have such a complex design like that, rather than just eliminating the rather useless Ferrand stop? Plus if the downtown relief line goes to Don Mills/Eglinton, you need provision for that in the design, which makes the design of the station even more complicated.

I don't think it is very complex, to extend the tunnel by 60 m or even 120 m.

Downtown relief line station will be close to Don Mills and rather far from Ferrand, so yes it will add complecity, but totally unrelated to the design of the eastern tail.

Ferrand stop will help riders walking from the residential area, located south of Eglinton and just west from DVP.

 

[dowlingm]

They should have done cut and cover! This is ridiculous. Cut and Cover would have save 5 years and maybe this is up and running in 2018! Same with the DRL. Hell cut and cover would all us to do all the Transit projects faster.

Pardon me for judging you based on your username, but maybe you could do a Street View trip through Eglinton say from the Allen to Bayview and then imagine how a cut/cover would go. The property owners along there won't be caught napping like the ones on Vancouver's Cambie Street were. The reference to subway performance at high grades is interesting, since there was a big deal made about these tunnels being able to be retrofitted for subway by which I think most people thought steel-on-steel.

 

[innsertnamehere]

Dan actually lives in minniopolis, so it is understandable that he doesn't know the area that well.

 

[denfromoakvillemilton]

Pardon me for judging you based on your username, but maybe you could do a Street View trip through Eglinton say from the Allen to Bayview and then imagine how a cut/cover would go. The property owners along there won't be caught napping like the ones on Vancouver's Cambie Street were. The reference to subway performance at high grades is interesting, since there was a big deal made about these tunnels being able to be retrofitted for subway by which I think most people thought steel-on-steel.

I live in the city, but I hear your responses. I agree now. I guess I was wrong.

 

[ssiguy2]

I'm the one that lives in suburban Rainforestcity and am a stauch critic of the obscene waste of funds resulting from the Eglinton/SRT combo, perhaps you were think of me?