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

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

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.

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

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)

On Sun, 13 Sep 2009 13:31:09 -0500, (Mark Brader) wrote:

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.

Someone could fall out of a normal train's doors and break their neck
- it's well over a metre, and an uncontrolled fall from that height
could do plenty of damage.

Someone could also fall off a station platform as-is, but this seems
not to happen with any frequency.

Neil

--
Neil Williams
Put my first name before the at to reply.

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.

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.