[nfitz]

Regenerative braking had been a thing for awhile now.

It's been many decades since I first heard about it. Didn't the Montreal Metro start incorporating this into designs in the 1970s?

 

[Northern Light]

Don't elevators induce safety concerns that escalators solve, such as open airness and not being confined to small spaces, or an I being too liberal here.

They can. However, lets first note that these will be high capacity elevators, not your typical apartment/condo/office building elevator; in this day and age they will almost certainly all have security cameras as well.

We don't know what design decisions are being taken as yet, but there is a good chance the elevators will have glass/transparent doors which provide some additional safety.

Certainly they are less 'airy'; and there is a theoretical safety difference vs escalators in terms of the ability to 'call for help' and visibility. However, in the real world, elevators will have alarms, and escalators in low-use stations at 11pm don't have many people around if someone decides to be a problem to you 1/2 way up.

With elevators, you can always take a pass on entering one if the look of a fellow passenger is concerning; take the next one; and/or take the stairs.

 

[AlvinofDiaspar]

It's been decades since I first heard about it. Didn't the Montreal Metro start incorporating this into designs in the 1970s?

Not sure about Montreal, but we had it since T1s.

AoD

 

[nfitz]

Not sure about Montreal, but we had it since T1s.

I was thinking of the grade of tunnel/station design aspect (fanoftoronto said "stations shallower than the rest of the tunnel").

But on that thought, I'm wondering what the late 1970s Metro rollingstock can do (what we used to call the new cars ... I guess now they are the old cars). And the newer late 2010s/early 2020s stock.

 

[AlvinofDiaspar]

They can. However, lets first note that these will be high capacity elevators, not your typical apartment/condo/office building elevator; in this day and age they will almost certainly all have security cameras as well.

We don't know what design decisions are being taken as yet, but there is a good chance the elevators will have glass/transparent doors which provide some additional safety.

Certainly they are less 'airy'; and there is a theoretical safety difference vs escalators in terms of the ability to 'call for help' and visibility. However, in the real world, elevators will have alarms, and escalators in low-use stations at 11pm don't have many people around if someone decides to be a problem to you 1/2 way up.

With elevators, you can always take a pass on entering one if the look of a fellow passenger is concerning; take the next one; and/or take the stairs.

Not sure how much benefit transparent doors can offer in terms of safety given it's a much longer ride - and there is not much by the way of "eyes" along the way.

AoD

 

[Northern Light]

Not sure how much benefit transparent doors can offer in terms of safety given it's a much longer ride - and there is not much by the way of "eyes" along the way.

AoD

There is no such thing as a risk-free environment, but I haven't heard of widespread robberies/assaults in TTC elevators (though perhaps I've missed that).

****

I would add, these will not be the low-speed hydraulic elevators of TTC retrofits. The capacity wouldn't work, these will have to operate at a decent clip.

 

[fanoftoronto]

Regenerative braking had been a thing for awhile now.

AoD

Regenerative braking only works up until a certain limit. Beyond this limit, we always have to rely on mechanical brakes to bring the vehicle to a complete stop. We'd not have such soot covered track levels if the T1s and the Rockets were using regenerative breaking 100% of the time. A shallower station would further help with the regenerative braking by assisting in the deceleration without relying on the mechanical brakes.

Furthermore, if the tunnel dips after the station, it helps reduce energy use for acceleration when departing the station as well.

The next benefit of a shallower station is that there is less digging required to build the station. Lower upfront construction cost.

Last benefit is a recurring saving. Less circulation required as the air doesn't need to move as far to get to platform level. Additionally, we'll have a smaller concourse level, or lesser overall open cubic feet within the station itself, meaning lesser ongoing heating and cooling costs.

Though, if we're going 35 m deep, we could potentially also heat the station using a geo-thermal heat pump. We're already at the minimum depth required for geo-thermal. The geo-thermal system might be comparable in price to comparable forced air heating as we have lesser digging required. While also reducing the ongoing costs for the stations.

 

[adys123]

Regenerative braking only works up until a certain limit. Beyond this limit, we always have to rely on mechanical brakes to bring the vehicle to a complete stop. We'd not have such soot covered track levels if the T1s and the Rockets were using regenerative breaking 100% of the time. A shallower station would further help with the regenerative braking by assisting in the deceleration without relying on the mechanical brakes.

Furthermore, if the tunnel dips after the station, it helps reduce energy use for acceleration when departing the station as well.

The next benefit of a shallower station is that there is less digging required to build the station. Lower upfront construction cost.

Last benefit is a recurring saving. Less circulation required as the air doesn't need to move as far to get to platform level. Additionally, we'll have a smaller concourse level, or lesser overall open cubic feet within the station itself, meaning lesser ongoing heating and cooling costs.

Though, if we're going 35 m deep, we could potentially also heat the station using a geo-thermal heat pump. We're already at the minimum depth required for geo-thermal. The geo-thermal system might be comparable in price to comparable forced air heating as we have lesser digging required. While also reducing the ongoing costs for the stations.

Certainly there are savings with this type of design. But we would not be talking about metres, there is still a track grade that has to be maintained.

 

[T3G]

Not sure about Montreal, but we had it since T1s.

AoD

Much earlier than that - since the H5s in 1976.

 

[fanoftoronto]

Certainly there are savings with this type of design. But we would not be talking about metres, there is still a track grade that has to be maintained.

Edit: Please ignore the following. 10% is way too much!

Original post:
I mean, trains can handle grades up to 10%. So over a length of 100 metres, we can go up 10 metres, which would bring the depth of the station from 35 metres down to 25 metres. Or you can go 150 metres of tunnel, meaning we can go up 15 metres, and reduce the depth of the station to 20 metres.

I believe the bigger issue is that the bedrock is situated at the 35 metres depth. Not sure what the engineering challenges are to keep going between bedrock and closer surface back and forth.

 

[T3G]

mean, trains can handle grades up to 10%

I really doubt this is true. If the vehicle were specially spec'ed that would be one thing, but I doubt there's any train that doesn't need to climb such grades that would be powered for such.

I don't have current data for the TRs (though I don't doubt they'd post similar figures), but the H1-6 and T1 cars are limited to 3.5% grades. The CLRVs, which were considerably more nimble than a subway car (an empty car weighing 22k kg compared to an empty H5 at 30k) were only designed for 8% grades.

10% is a very steep grade, well outside of the norm of what most transit systems would encounter.

 

[fanoftoronto]

I really doubt this is true. If the vehicle were specially spec'ed that would be one thing, but I doubt there's any train that doesn't need to climb such grades that would be powered for such.

I don't have current data for the TRs (though I don't doubt they'd post similar figures), but the H1-6 and T1 cars are limited to 3.5% grades. The CLRVs, which were considerably more nimble than a subway car (an empty car weighing 22k kg compared to an empty H5 at 30k) were only designed for 8% grades.

10% is a very steep grade, well outside of the norm of what most transit systems would encounter.

Apologies, I stand corrected. 3.5% would then need a lot longer of a run-up for grade changes.

Even with 3.5% we can bring the depth of the tunnel up by 5 metres over 150 metres. Though I admit that's definitely not as impressive! Haha

 

[adys123]

I mean, trains can handle grades up to 10%. So over a length of 100 metres, we can go up 10 metres, which would bring the depth of the station from 35 metres down to 25 metres. Or you can go 150 metres of tunnel, meaning we can go up 15 metres, and reduce the depth of the station to 20 metres.

I believe the bigger issue is that the bedrock is situated at the 35 metres depth. Not sure what the engineering challenges are to keep going between bedrock and closer surface back and forth.

I really doubt this is true. If the vehicle were specially spec'ed that would be one thing, but I doubt there's any train that doesn't need to climb such grades that would be powered for such.

I don't have current data for the TRs (though I don't doubt they'd post similar figures), but the H1-6 and T1 cars are limited to 3.5% grades. The CLRVs, which were considerably more nimble than a subway car (an empty car weighing 22k kg compared to an empty H5 at 30k) were only designed for 8% grades.

10% is a very steep grade, well outside of the norm of what most transit systems would encounter.

Yeah, this is not something that is available readily. 10% grades are extremely steep, even 5% grades require specific requirements already.

 

[KevinT]

Spadina is a odd duck - with that much space devoted to the elevator bank, you can probably put a pair of escalators in scissors format.

A double spiral escalator wrapped around twin elevators would probably have more throughput, and be quite the signature to boot. I wonder if that would cost more or less than all of the elevators that they're putting in? It would eliminate the transfer landings of a stack of scissor escalators...

 

[mind_the_gap]

To me, this elevator-only access at Spadina will become one of the coolest aspects of our (finally) evolving rapid transit network. The only other example I’m aware of in Canada of elevator-reliant stations is Édouard-Montpetit (REM).

Not to sound like a foamer, but elevators are essentially trains travelling vertically.

It’s cool to see that they’re seemingly planning for double-sided elevators (ala. SRT at Kennedy), in one side, out the other. Guess, we’ll finally see Presto gates set to one-way operation.