|
EU lending for Crossrail
On Sep 13, 3:47*am, Miles Bader wrote:
Andy writes: The Z22500 EMUs on RER Line E in Paris (and the similar MI2N on RER line A) would be the way to go, each coach having three sets of extra- wide double doors. This comes at the penalty of some seating of course. Are their double-floor cars "mostly sitting" cars? How well do double-floor cars work with "mostly standing" designs? They are a combination, the upstairs bit has two long seating bays with no access to the middle set of doors, the downstairs bits has access to all three sets of doors. There are large areas for standing by the doors. All of the double-floor cars I've seen in real life have clearly been oriented towards seated passengers, and this obviously puts a big restriction on their capacity. Extremely crowded trains with mostly standing passengers can work reasonable well because they have _so much_ door area (on some train cars that I've seen, around 50% of the wall area is doors), that it's possible for people to get on and off despite the crush loading. *It allows not just massive "bandwidth" for major stations, but also high "accessibility" for some poor schmuck that just wants to get off at a minor station, where even crossing the car to get to a very nearby door is difficult. But how would that work in a double-floor car? *I can imagine that something that was basically like two single-floor cars stacked vertically could work, but obviously that would require a _massive_ amount of additional station infrastructure -- it would basically require all stations to have double-floor platforms. [Many Japanese commuter trains have some double floor cars e.g. "green cars", but their capacity is quite restricted compared to the normal single-floor cars] The Z22500 have a high percentage of door, probably about 30%. There are some diagrams and pictures he http://www.metro-pole.net/expl/materiel/mi2n/mi2n.html http://www.railfaneurope.net/pix/fr/...22550/pix.html |
EU lending for Crossrail
On Sat, 12 Sep 2009, Dr J R Stockton wrote:
In uk.transport.london message , Thu, 10 Sep 2009 17:33:10, Tom Barry posted: One other benefit of double-deck trains, by the way, is shorter train lengths for the same capacity (which saves money on station lengths, but not in the capacity of escalators etc.). That's at the expense of dwell times, though, unless you do something really clever like having double-height platforms with doors on the upper deck too (I like the sound of that, actually). At busy stations, there can be a lower-deck platform on one side of the train and an upper-deck platform on the other side. Has this actually been done anywhere? Can i see pictures? At less busy stations, rely on the carriages' internal stairs. Or have little movable steps, like little airports do. tom -- Also, a 'dark future where there is only war!' ... have you seen the news lately? -- applez |
EU lending for Crossrail
Tom Barry:
One other benefit of double-deck trains, by the way, is shorter train lengths for the same capacity (which saves money on station lengths, but not in the capacity of escalators etc.). That's at the expense of dwell times, though, unless you do something really clever like having double-height platforms with doors on the upper deck too (I like the sound of that, actually). J.R. Stockton: At busy stations, there can be a lower-deck platform on one side of the train and an upper-deck platform on the other side. Tom Anderson: Has this actually been done anywhere? Can i see pictures? The upper deck would have to have doors that open about 8-10 feet (2.5-3 m) above rail level. Which means that if those doors ever opened outside a station, someone could fall out and break their neck. I find it hard to believe that safety authorities anywhere would accept that. It's different for elevators, because the elevator shaft provides protection. I used to work in a building with double-deck elevators. If you worked on an even-numbered floor, to get there you boarded from the ground floor. For odd-numbered floors you'd take the escalator to the basement concourse to catch the elevator. (As this was in Canada, the ground floor was also floor 1, which seems to break the pattern; but floor 2 only existed in the lobby area and was not served by the main elevators. Going back down, you'd just have to take whichever deck arrived, and wouldn't have a choice of whether you arrived at the ground or basement level. Both decks had buttons for all floors they could reach; they just didn't all work when you were on the ground or basement. So trips between floors above ground were generally like using a normal elevator.) -- Mark Brader, Toronto This is a signature antibody. Please remove any viruses from your signature. My text in this article is in the public domain. |
EU lending for Crossrail
On Sun, 13 Sep 2009, Mark Brader wrote:
Tom Barry: One other benefit of double-deck trains, by the way, is shorter train lengths for the same capacity (which saves money on station lengths, but not in the capacity of escalators etc.). That's at the expense of dwell times, though, unless you do something really clever like having double-height platforms with doors on the upper deck too (I like the sound of that, actually). J.R. Stockton: At busy stations, there can be a lower-deck platform on one side of the train and an upper-deck platform on the other side. Tom Anderson: Has this actually been done anywhere? Can i see pictures? The upper deck would have to have doors that open about 8-10 feet (2.5-3 m) above rail level. Which means that if those doors ever opened outside a station, someone could fall out and break their neck. I find it hard to believe that safety authorities anywhere would accept that. Much as they wouldn't accept the idea of trains driven by computers, or without guards on board? As with those examples, it's a matter of building enough safeguards into it that it's safe. Perhaps the doors could be built to only open once a positive physical interlock with a platform was established, a bit like a space station docking port. Of course, the you have the question of whether the benefit-to-cost ratio of the system with the necessary safeguards included would still be greater than one. It's different for elevators, because the elevator shaft provides protection. I used to work in a building with double-deck elevators. If you worked on an even-numbered floor, to get there you boarded from the ground floor. For odd-numbered floors you'd take the escalator to the basement concourse to catch the elevator. (As this was in Canada, the ground floor was also floor 1, which seems to break the pattern; but floor 2 only existed in the lobby area and was not served by the main elevators. Going back down, you'd just have to take whichever deck arrived, Wouldn't that always be the same for a given floor? Or did the lifts not follow the synchronisation pattern on the way down? and wouldn't have a choice of whether you arrived at the ground or basement level. Ah, they didn't, then. Interesting! Both decks had buttons for all floors they could reach; they just didn't all work when you were on the ground or basement. So trips between floors above ground were generally like using a normal elevator.) Even going up? Or did upward trips divide into two classes, those carrying people up from floors 0 and 1, where synchronisation was maintained (at least at the floors to which people from 0/1 were going), and those which were purely aerial, where it wasn't? tom -- I now have a problem with tomorrow. -- Graham |
EU lending for Crossrail
Bill Bolton wrote on 13 September 2009
02:32:41 ... "Richard J." wrote: The point is that if the stations with the heaviest passenger flows are in the central section where you want the greatest train frequency, then peak trains per hour will be limited by the increased dwell times there There is clearly a trade off between frequency and capacity, however I find it very hard to believe that in the Crossrail context the whole load of a train is going to change over at each of the 6 CBD stations. Nobody, certainly not I, has said that. You originally referred to "a significant percentage of the passenger carrying capacity of the DD train" boarding/alighting. In practice it doesn't work that way on *any* system and with good loading vestibule design on DD rolling stock, significant number of passengers can be handled at each heavily traffic station without the dwell time impacting the *actual track capacity* in terms of people moved. Yes, I agree that you could achieve the same track capacity by using DD trains at lower frequency with longer dwell times. But that doesn't necessarily mean that DD trains, with all the resultant extra infrastructure costs, actually *increase* the track capacity, which is what this sub-thread is all about. CityRail does it in Sydney using an all DD fleet without any particular problems. If you say so. According to the Sydney Morning Herald in April this year, "the pricing regulator found last year that the CityRail network was approaching timetable collapse under the weight of unprecedented demand as Sydney has grown." What actual train frequencies per track are currently achieved by CityRail in the CBD? It's not easy to work that out from the published timetables. -- Richard J. (to email me, swap 'uk' and 'yon' in address) |
EU lending for Crossrail
|
EU lending for Crossrail
Mark Brader:
The upper deck would have to have doors that open about 8-10 feet (2.5-3 m) above rail level. Which means that if those doors ever opened outside a station, someone could fall out and break their neck. I find it hard to believe that safety authorities anywhere would accept that. Neil Williams: Someone could fall out of a normal train's doors and break their neck... Someone could also fall off a station platform as-is, but this seems not to happen with any frequency. Actually it does. But safety authorities tend to be more worried about *new* hazards. -- Mark Brader "Finally no number of additional epicycles can Toronto hide the fact that We've Got a Problem Here." -- from a science book club promotion My text in this article is in the public domain. |
EU lending for Crossrail
Mark Brader:
... I used to work in a building with double-deck elevators. If you worked on an even-numbered floor, to get there you boarded from the ground floor. For odd-numbered floors you'd take the escalator to the basement concourse to catch the elevator. ... Going back down, you'd just have to take whichever deck arrived, Tom Anderson: Wouldn't that always be the same for a given floor? Or did the lifts not follow the synchronisation pattern on the way down? Correct, they didn't. Both decks had buttons for all floors they could reach; they just didn't all work when you were on the ground or basement. So trips between floors above ground were generally like using a normal elevator.) Even going up? Yes. -- Mark Brader, Toronto | "Men! Give them enough rope and they'll dig | their own grave." -- EARTH GIRLS ARE EASY My text in this article is in the public domain. |
| All times are GMT. The time now is 07:49 AM. |
Powered by vBulletin®
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004-2006 LondonBanter.co.uk