[ARG1]

TBM are single use items.
You don't take them apart and rebuilt it someplace else.
They are often just left in the ground after the tunnel is done

Very much not. In fact when you're a city that spends a lot of time building subways like its a factory line production with a consistent design and rolling stock (looks at Moscow for no particular reason), you can get away with just constantly reusing them to your hearts content. TBM done one section? Pick it up and plop it somewhere else you need it. Saves a ton of time and money not having to design a new TBM from scratch everytime you need to start a new project.

 

[crs1026]

Very much not. In fact when you're a city that spends a lot of time building subways like its a factory line production with a consistent design and rolling stock (looks at Moscow for no particular reason), you can get away with just constantly reusing them to your hearts content. TBM done one section? Pick it up and plop it somewhere else you need it. Saves a ton of time and money not having to design a new TBM from scratch everytime you need to start a new project.

Except that contractors don't, for a variety of reasons. Contractor A may not be successful at a second project where the requirements are compatible. Extracting and storing a TBM against future needs is a crapshoot. Transporting the TBM away may have its own technical challenges - depending where the extraction shaft is located, roads or waterways may not be helpful. As noted the technology may be changing, so a new and faster TBM may be a better economy for later projects than a slower but used and paid for TBM.

I do know of one project in Ontario where the original plan was to simply drive the TBM forward and bury it. It didn't happen, but that would havve been the cheapest and simplest solution.

If you want a lot of detail on TBM's, try here.

PS - the case for reuse is also being made, see here - but the authors acknowledge this is against conventional thinking.

- Paul

 

[ProjectEnd]

TBM are single use items.
You don't take them apart and rebuilt it someplace else.
They are often just left in the ground after the tunnel is done

As @fanoftoronto notes above, that's simply not true. In many cases you're not wrong, but as a 'rule' it's incorrect.

 

[MrGoose]

And I find it amusing that the "anti-subway" crowd often argue we shouldn't build subways because they're "too expensive."
Whatever money we saved by building a LRT instead of a subway, the government has already frivolously spent on another endeavor/project. So I say we just go "all in". This government has no intentions of paying off their debt load and will continue to rack up debt.
We care so much about the costs of these project, but in the end, we just get low quality, street car style, non-rapid transit, while still being in crippling debt. At least let me ride shiny, new subways while this country is in crippling debt.

How much money did we save building a LRT across Eglinton instead of a subway?

We didn't save much if any money. If anything, we spent more money to get less.
1. The tunnels are the same diameter
2. The stations are about the same size or larger than they would have had to be to accomodate a subway with similar / more ridership (because of the lower capacity of low floor cars)
3. There are twice as many stations because of the insanely close station spacing.

 

[ARG1]

Except that contractors don't, for a variety of reasons. Contractor A may not be successful at a second project where the requirements are compatible. Extracting and storing a TBM against future needs is a crapshoot. Transporting the TBM away may have its own technical challenges - depending where the extraction shaft is located, roads or waterways may not be helpful. As noted the technology may be changing, so a new and faster TBM may be a better economy for later projects than a slower but used and paid for TBM.

I do know of one project in Ontario where the original plan was to simply drive the TBM forward and bury it. It didn't happen, but that would havve been the cheapest and simplest solution.

If you want a lot of detail on TBM's, try here.

PS - the case for reuse is also being made, see here - but the authors acknowledge this is against conventional thinking.

- Paul

FWIW I'm not advocating for reusing TBMs for "Future Use", but rather pointing out that if you are building a ton of subway lines one after another continuously. Obviously this doesn't make sense in Toronto where we build projects at erratic intervals, and when we do they use various different standards with different train types, diameter requirements, etc.

But, thank you for the links.

 

[Amare]

We didn't save much if any money. If anything, we spent more money to get less.
1. The tunnels are the same diameter
2. The stations are about the same size or larger than they would have had to be to accomodate a subway with similar / more ridership (because of the lower capacity of low floor cars)
3. There are twice as many stations because of the insanely close station spacing.

A note about #1; the diameter of the Crosstown tunnels are actually bigger than your traditional Toronto subway tunnel, to accommodate the overhead catenary line. Ultimately that drives the cost of the project up even more then a standard tunnel bore.

 

[nfitz]

A note about #1; the diameter of the Crosstown tunnels are actually bigger than your traditional Toronto subway tunnel, to accommodate the overhead catenary line. Ultimately that drives the cost of the project up even more then a standard tunnel bore.

Slightly. However the other two points aren't true. The station spacing has nothing to do with it being LRT versus subway. The spacing from Laird (comparable to Chester) to Keelesdale to Mount Dennis (10.2 km) is significantly further apart than on Line 2 from Chester to Keele (10.3 km).

There's 11 stations between Laird and Keelesdale (average spacing 850 m) and 15 between Keele and Chester (average spacing about 645 m). That's 1/3 less stations, not more.

The comment about low-floor LRTs impacting station size also don't make sense. The capacity isn't that much lower; some of it driven by the trains a bit narrower. The Eglinton line trains are maximum of 90 metres. That's shorter than the trains now on the Sheppard line (about 92 m!).

We can actually compare the original station design for Eglinton West using subway to the current design with LRT. The original design allowed for 152 m trains!

The reality is, it would have been more expensive to use the subway design than the LRT design for the grade-separated section.

Still, the line is mostly grade-separated. About 20.5 km that is grade-separated west of Leslie, and 7.3 km that's partially got intersections (less really when you account for the 500 m from Kennedy to the first intersection, and the 1.5 km from Leslie to the 404).

So ultimately about 25 km once the 4.5 km to the airport is built. Another 2 km from where the other 2 stations are. So 27 km grade separated (84%) versus 5.3 km with some traffic lights (16%).

So cheaper, and only a small fraction with lights.

 

[ARG1]

Slightly. However the other two points aren't true. The station spacing has nothing to do with it being LRT versus subway. The spacing from Laird (comparable to Chester) to Keelesdale to Mount Dennis (10.2 km) is significantly further apart than on Line 2 from Chester to Keele (10.3 km).

There's 11 stations between Laird and Keelesdale (average spacing 850 m) and 15 between Keele and Chester (average spacing about 645 m). That's 1/3 less stations, not more.

The comment about low-floor LRTs impacting station size also don't make sense. The capacity isn't that much lower; some of it driven by the trains a bit narrower. The Eglinton line trains are maximum of 90 metres. That's shorter than the trains now on the Sheppard line (about 92 m!).

We can actually compare the original station design for Eglinton West using subway to the current design with LRT. The original design allowed for 152 m trains!

The reality is, it would have been more expensive to use the subway design than the LRT design for the grade-separated section.

Still, the line is mostly grade-separated. About 20.5 km that is grade-separated west of Leslie, and 7.3 km that's partially got intersections (less really when you account for the 500 m from Kennedy to the first intersection, and the 1.5 km from Leslie to the 404).

So ultimately about 25 km once the 4.5 km to the airport is built. Another 2 km from where the other 2 stations are. So 27 km grade separated (84%) versus 5.3 km with some traffic lights (16%).

So cheaper, and only a small fraction with lights.

If you wanted to build a subway with the same capacity as this LRT, you could do so with much shorter vehicles (and thus stations), which would save you a ton of money.

 

[nfitz]

If you wanted to build a subway with the same capacity as this LRT, you could do so with much shorter vehicles (and thus stations), which would save you a ton of money.

Somewhat shorter trains. Let's not go overboard here. Published Finch West capacity for the 96-metre long trains there is 584 people. The 92-metre Sheppard trains are 720; the old T-1 trains on Sheppard were 668.

 

[ARG1]

Somewhat shorter trains. Let's not go overboard here. Published Finch West capacity for the 96-metre long trains there is 584 people. The 92-metre Sheppard trains are 720; the old T-1 trains on Sheppard were 668.

Don't forget to factor the increased headways you can run the trains at due to being fully grade separated, plus the ability to run the trains automated.

 

[Aplus23]

Don't forget to factor the increased headways you can run the trains at due to being fully grade separated, plus the ability to run the trains automated.

The entire section of this part of the line is grade separated tho

 

[smallspy]

If you wanted to build a subway with the same capacity as this LRT, you could do so with much shorter vehicles (and thus stations), which would save you a ton of money.

Save a little money, not a ton.

Most of the cost of any station is the fact that you're putting a station there, and all of the stuff that has to go along with that (such as moving utilities, SoE, etc.). Once you start digging the hole, the fact that it is 500 truckloads versus 400 truckloads actually matters very little as the difference in cost is minor.

Dan

 

[MrGoose]

Somewhat shorter trains. Let's not go overboard here. Published Finch West capacity for the 96-metre long trains there is 584 people. The 92-metre Sheppard trains are 720; the old T-1 trains on Sheppard were 668.

So what your saying is that if we had just switched out the train stock, and done anything else to the signal, station sizes, headway etc, we would’ve gotten a 22% boost in capacity?

That’s a lot of ridership left on the table.

 

[fanoftoronto]

Save a little money, not a ton.

Most of the cost of any station is the fact that you're putting a station there, and all of the stuff that has to go along with that (such as moving utilities, SoE, etc.). Once you start digging the hole, the fact that it is 500 truckloads versus 400 truckloads actually matters very little as the difference in cost is minor.

Dan

The Ontario Line is being touted as having cost savings by having 90m stations vs 150m (typical TTC subway station) stations. Also, it's not just truckloads of dirt being carried away, you also have vastly reduced square footage to finish as station interiors, lesser ventilation requirements for the smaller cubic volume, reduced ongoing maintenance due to smaller size, and increased footfall (revenue) due to a much more reliable service.

Arguably, we could've gone with 60m trains and stations, fully grade separated, using smaller diameter tunnels (or elevated in the East and West ends), fewer east end stations, and automated trains for the same amount of money.

Don't get me wrong, I'm happy that we're getting something on Eglinton after so long, but it's definitely not worth the money spent here.

It's like paying for a Lexus SUV but getting a Toyota Corolla. Good overall car, but overpriced.

 

[MrGoose]

Save a little money, not a ton.

Most of the cost of any station is the fact that you're putting a station there, and all of the stuff that has to go along with that (such as moving utilities, SoE, etc.). Once you start digging the hole, the fact that it is 500 truckloads versus 400 truckloads actually matters very little as the difference in cost is minor.

Dan

You’re gonna be spending a ton of money on the retrofits to the eastern leg and suffering through delays, when some guy in an SUV runs into Don Mills station or was drunk driving and takes out a catenary pole.

And you’ll be spending tons of money trying to up the capacity when ridership inevitably grows beyond the predictions in 10 years because of all the development happening along the route.