Voltz
Senior Member
Any idea if the priority equipment will detract an approaching LRV from far enough away o be able to give it a green light by the time it arrives the large majority of the time, or are we stuck with phase rotations?
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jcam
Active Member
Crosstown TBM diameter was 256". TYSSE was 246", Sheppard subway was 232" I think. (I use inches because that's how we numbered our machines). From my recollection of the cross sections, ECLRT needed the extra 10" primarily for the catenary.
11th
Senior Member
It's actually better for cars. Normally, there are more through traffic than turning traffic. It can also benefit turning traffic, as they are less likely having to wait a whole light cycle, because the turn phase ends right as they reach the intersection.
felix123
Active Member
I wonder why they're even calling it transit signal priority then...
Steve X
Senior Member
It really depends on location. If there's more left turning traffic compare straight traffic like Eglinton/Leslie, then all the left turning vehicles will back up and block straight traffic lanes. Leading left would be better in this case.
If left turning vehicles are often stuck behind a queue of straight traffic, lagging left would help them get to the left turning lane before their lagging green.
Leslie/Eglinton is a complete mess cause of the extensively long left turning cycle plus pedestrians trigger their own crossing phase if they need to cross Eglinton. Transit phase insertion would be needed to get trains through the intersection faster. However, this will lead to more pedestrians darting across the road to catch their trains.
smallspy
Senior Member
Not quite the catenary, but more specifically for dynamic clearance around the pantograph.
Dan
doublemint
New Member
So having the information we have, why does anyone seem to think we will get anything beyond phase rotation? It's quite clear that the reason that there is phase rotation on only 2-3 intersections each for Line 5 and Line 6 is the same reason there's phase rotation on only 2-3 intersections on Spadina (the pilot, mind you). It's not because they cannot do it for the whole line, but because they, in classic TTC fashion, are overly cautious.
Forgive my pessimism, but I have seen absolutely no indication of the city or the TTC having a desire to continue with TSP by implementing phase insertion or red truncation (especially because for many intersections the minimum walk time corresponds to the minimum green time, and the addition of pedestrian refuge islands is not only a logistical and construction nightmare, but will be ridiculously expensive because it's Toronto. In the city and province's eyes, the two projects are already a gaping money pit, thus they don't want to throw more money into it).
From my perspective, it seems like the city and TTC will work to implement most or all intersections on Line 5 and Line 6 with green extensions and phase rotations, and nothing else. At the end of the day, they don't want to upset drivers and especially not the province (who, as we have already seen, can and previously has shut many good ideas down at the drop of a hat), so this implementation of phase rotation seems less like a "we want transit to go faster than cars" and more like a "here, damn".
Besides that, there are many other more meaningful changes that the TTC can and should implement across their surface transit network than TSP (dual blade switches, 25 km/h speed restriction through intersections or 10 km/h in the case of streetcars when crossing over other streetcar tracks, lack of barriers along Line 6, conservative accelerating and braking profiles, poor rolling stock on Line 6, etc.).
All of this because the TTC and Metrolinx don't want to upset car drivers and operate on an inherently flawed mission statement of wanting to move as many people to their destination as possible (in reality, it should be to move as many people to their destination as quickly as possible).
Forgive my pessimism, but I have seen absolutely no indication of the city or the TTC having a desire to continue with TSP by implementing phase insertion or red truncation (especially because for many intersections the minimum walk time corresponds to the minimum green time, and the addition of pedestrian refuge islands is not only a logistical and construction nightmare, but will be ridiculously expensive because it's Toronto. In the city and province's eyes, the two projects are already a gaping money pit, thus they don't want to throw more money into it).
From my perspective, it seems like the city and TTC will work to implement most or all intersections on Line 5 and Line 6 with green extensions and phase rotations, and nothing else. At the end of the day, they don't want to upset drivers and especially not the province (who, as we have already seen, can and previously has shut many good ideas down at the drop of a hat), so this implementation of phase rotation seems less like a "we want transit to go faster than cars" and more like a "here, damn".
Besides that, there are many other more meaningful changes that the TTC can and should implement across their surface transit network than TSP (dual blade switches, 25 km/h speed restriction through intersections or 10 km/h in the case of streetcars when crossing over other streetcar tracks, lack of barriers along Line 6, conservative accelerating and braking profiles, poor rolling stock on Line 6, etc.).
All of this because the TTC and Metrolinx don't want to upset car drivers and operate on an inherently flawed mission statement of wanting to move as many people to their destination as possible (in reality, it should be to move as many people to their destination as quickly as possible).
Thaboss
Active Member
Because in each an every annoucment, they've been abundantly clear that phase rotation is not where they'll stop.
Until we have someone telling us otherwise there's no reason to doubt.
doublemint
New Member
The only verbiage given is the implementation of more "Aggressive" Transit Signal Priority. This "Agressive" TSP is what mayor Chow hinted at being implemented this past week. What was implemented? Phase rotation at a couple intersections. As far as the City and TTC are concerned, anything that goes beyond conditional TSP (i.e. only if the trains are behind schedule, giving extended greens) counts as more aggressive TSP.
Furthermore, in the TTC board meeting last month, the only TSP addition that Mandeep Lali mentioned outside of extended greens is phase rotation. There was no mention of phase insertion, red truncation, or signal pre-emption.
I'd love to be proven wrong, so could you please provide me with any announcements they made outlining those specific forms of TSP?
adys123
Active Member
Conditional and unconditional TSP describe separate things (the way it's activated), and not the techniques that it would operate under. For example, you can absolutely have conditional phase rotation.
doublemint
New Member
Thank you for the clarification, but that unironically muddies what the City could possibly mean by "Aggressive" TSP even more.
Thaboss
Active Member
Just have some patience. We'll know literally know in a month or two.
urbanclient
Active Member
Crosstown was 256" and/or 259". TYSSE was 241" at most. The TYSSE TBMs were not 10" smaller, but 15" compared to the current Line 5 and 18" compared to the Eglinton West extension.
I am converting from metric sources to inches to compare. TYSSE was 6.12 metres or just under 241 inches. As far as I know, Crosstown TBM was 6.5 m or 256 inches, but Metrolinx has a habit of arbitrarily rounding things. Crosstown West was 6.58 m or 259 inches, but that could be due to different soil conditions necessitating a wider TBM rather than being a more precise figure.
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The notion that OCS or pantograph or even safety walkways forced Eglinton to have 6.5 metre TBMs and 5.75 m wide tunnels is misleading, if not an outright myth. I've seen it repeated ad nauseam going back at least 4 years on this forum. On the contrary, the tunnels could've been narrower.
For those that still think Eglinton's gargantuan tunnels were optimal given the clearances needed (dynamic envelope, OCS, emergency walkway 0.29 m above TOR etc.), my mind is boggled. Have y'all tried riding Line 5 from behind the cab?
The tunnel is massive compared to the vehicle and overhead, moreso than any LRT, subway or metro that I have ever been on.
Food for thought: Flexity Freedoms are 2.65 m wide, 3.6 m tall, with overhead wire 3.9 m high. Toronto Rockets are 3.137 m wide, 3.645 m tall. Bear in mind, the pantograph and OCS systems between the train roof and the tunnel crown do not need the entire 2.65 m width, much less the wider dynamic envelope + extra margin.
The height of the safety walkway (related to platform / vehicle floor height) does make Eglinton proportionally hog more space given the same walkway size. But I'll get back to this with more boring math and comparable rail tunnels when I have the time.
To make future projects better, I hope we can recognize (minor) shortcomings of past projects instead of handwaving them out of existence. Some people seem to think there is nothing suboptimal about Line 5. Apparently the only flaws are with the execution i.e. initially weak TSP and speed limits.
I am not here to bring up capacity & throughput. But I am tired of hearing the same excuses for why the tunnel is so big.
TYSSE Page 32/37: "6.12 m" https://transittoronto.ca/images/Hwy_407_Display_Boards_Open_House_REV.pdf
Eglinton: "6.5 m in diameter" https://transittoronto.ca/archives/reports/eglinton-tbm-backgrounder-metrolinx.pdf
Eglinton West ext.: "6.58 metres in diameter" https://www.metrolinx.com/en/discover/tunnelling-starts-on-the-Eglinton-crosstown-west-extension
OCS wire Page 511/632: "3900 mm at Exclusive ROW tunnel sections" https://assets.metrolinx.com/image/..._Design_Criteria_Manual_DCM_LRT-001_REV01.pdf
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smallspy
Senior Member
And yet, that was the information given by people directly involved in the design of the line. And in the EA, for the whole world to see, for that matter.
I'm far more inclined to believe them than some rando on the web.
Dan
ssiguy2
Senior Member
I think you guys are putting too much emphasis on the TTC and not where the ultimate determination is made.......City Hall.
It is the City that controls the transportation dept and the TTC has to work within those mandates whether they like it or not. The TTC has absolutely no control over lights, traffic flow, speed {at ground level}, or even pedestrian safety. These are all under the domain of the City. The City also controls the TTC's budget and when you control the purse strings, you run the show. Full stop. If you are looking for a place to throw blame, look no further than your gutless Mayor & Council,
It is the City that controls the transportation dept and the TTC has to work within those mandates whether they like it or not. The TTC has absolutely no control over lights, traffic flow, speed {at ground level}, or even pedestrian safety. These are all under the domain of the City. The City also controls the TTC's budget and when you control the purse strings, you run the show. Full stop. If you are looking for a place to throw blame, look no further than your gutless Mayor & Council,