montréal REM de l'Est

[champdemars]

Il y a 1 heure, Enalung a dit :

There's been quite a few suggesting the use of a tramway instead of REM. Noise has also been a major concern. For theses reasons, this video caught my attention this morning.

It argues that low floor LRT / tramways are more noisy then high floor LRT. The argument makes a lot of sense given how the wheels are affixed to the vehicle. On a high floor train, the entire bogey can pivot independently of the cars on top. This allows the bogey to naturally follow the curve / be at a different angle then the car on top. On a low floor train, the axel is fixed directly to the cars and thus do not have the ability to pivot. The flanges end up rubbing against the rails which results in more wheel screeching as well as wear and tear on the wheels and rails.

He also points out that the need for wheel wells create several issues. It reduces the amount of doors which slows down embarking and disembarking. It creates narrow passageways where the wheels are inserted which can make it harder for passengers with mobility aids to move around. It also diminishes the amount of space available for passengers, and thus, the capacity of the system.

 

Pour avoir essayé le O-train à Ottawa j’ai été surpris du bruit à l’intérieur du train et du fait qu’on ressentait les roues gratter sur les rails.

 

[Rocco]

9 minutes ago, champdemars said:

Pour avoir essayé le O-train à Ottawa j’ai été surpris du bruit à l’intérieur du train et du fait qu’on ressentait les roues gratter sur les rails.

 

O-Train est un mauvais concept. Ils ont fait un tramway sur une emprise de train avec des vitesses de train. Ridicule, absurde, tout pour couper les coûts. Voilà ce que ça donne. Bâclé.

[champdemars]

il y a 12 minutes, Rocco a dit :

O-Train est un mauvais concept. Ils ont fait un tramway sur une emprise de train avec des vitesses de train. Ridicule, absurde, tout pour couper les coûts. Voilà ce que ça donne. Bâclé.

… ce qui va dans le sens de Reece Martin qui dit que bien des fois on prend des trains à plancher bas parce que c’est des trains cools. Il ne se servent même pas des avantages de ce type de train.

[SameGuy]

I think Skoda makes LF trams with articulated bogeys. Ask @Rotax. 😉

[Enalung]

2 hours ago, SameGuy said:

I think Skoda makes LF trams with articulated bogeys. Ask @Rotax. 😉

That looks like a perfect place for snow to accumulate and cause all kind of problems. Also, from the Wikipedia article:

Quote

The Alstom Citadis X04, an experimental 100% low floor tram currently being developed with pivoting bogies (but with sections of high floor seating over the bogies). [...]  Most of the tram floor is 350 mm (13.78 in) above the rails, but the height over the bogies is 450 mm (17.72 in) above the rails. The corridor above the central bogies is 700 mm (27.56 in) wide.

So, we're talking about 2 levels. Accommodating the pivot also means that he wheel wells have to be wider, taking even more space inside the tram. It's a messy compromise. The arguments made by RMTransit still stand.

Edit: I found the data sheet. It definitely bares the fact that pivoting boggies further reduce the passengers capacity.
https://autodocbox.com/Electric_Vehicle/72168712-New-generation-of-skoda-trams-in-european-cities.html

[TER200]

Il y a 4 heures, SameGuy a dit :

I think Skoda makes LF trams with articulated bogeys. Ask @Rotax. 😉

Le Citadis Spirit a des bogies qui pivotent (le Flexity Outlook/Freedom aussi, mais un tout petit peu).

Mais à cause du plancher bas, la place pour mettre les suspensions est très réduite donc elles amortissent généralement moins bien que sous un train à plancher haut.

[SameGuy]

I dunno, the version of the 15T in Qingdao is 35 metres long, has six doors per side, and a capacity of 300 passengers (compared to REM-B’s proposed 350 passengers in a 40 metre vehicle). It’s available in lengths up to five segments able to carry up to 539 passengers. It’s not measurably tighter than a fixed-bogey tram, other than in the accordions.

[SameGuy]

25 minutes ago, TER200 said:

Le Citadis Spirit a des bogies qui pivotent (le Flexity Outlook/Freedom aussi, mais un tout petit peu).

Les Citadis et Flexity ont des bogies Jabobs entre les sections, mais pas des bogies entièrement articulés aux deux bouts des rames comme sur le Škoda 15T ForCity, qui a en plus des bogies Jacobs modifiés sous les accordions qui pivotent indépendamment des joints Jacobs.

Citadis Spirit in Ottawa. These bogies don’t fully articulate.

[SameGuy]

2 hours ago, Enalung said:

Accommodating the pivot also means that he wheel wells have to be wider

I’m unclear on this. I’ve never seen “wheel wells” on a tram. The bogie is under the floor.

[Enalung]

59 minutes ago, SameGuy said:

I’m unclear on this. I’ve never seen “wheel wells” on a tram. The bogie is under the floor.

On a high floor tram, sure, it's under the floor. I was talking about low floor trams when i mentioned wheel wells. I'm sure that you've been on a low floor bus. They all have wheel wells right after you enter the bus. There just isn't enough space under the floor to put the wheels. Low floor trams suffer from a similar loss of space for the same reason.

Check this video 40 seconds in. That right there is your wheel wells. There's that weird half step with the seat positioned higher and the very narrow passageway. They are very careful on their promotional video not to put too much focus on that area of the tram.

Alstom Promotional Video

https://www.youtube.com/watch?v=SJd7FRzQAqw

A closer look...

https://www.youtube.com/watch?v=qJXI3xWIQJM