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Double decker trains

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Bald Rick

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I don't want to rain on anyone's parade, but with a height of 4,600mm...

... anyone sat on the top deck will be getting plenty of fresh air and possibly a haircut, at the first overbridge. Not to mention the 25kV that you could hang your coat on.
 

jopsuk

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so the train is too wide for the carriage length, too wide below platform level, may have the doors below the supposed standard for UK platforms and is far too tall. Other than that it'll fit!
 

janplomer

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Thank you for all your responses.
I have some additional parameters for you:
Distance between common bogies 23 300 mm
Distance between pivots 17 300 mm (they are not in bogie center)
Length of intermediate carbodies 23 000 mm
Height of entrance level 1 100 mm

If we discuss about dwell time, we should say, if the full capacity board on each stop. I mean, that full capacity change is only at terminal stations.

Patent is being validated this time and it now in czech only. It is about bogie pivot excentricity which alows greater distance between pivots than distance between bogie centres.

The kinematic gauge of a vehicle with clearance to platform (with clearance increase according to radius) is proven.
 

hwl

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Thank you for all your responses.
I have some additional parameters for you:
Distance between common bogies 23 300 mm
Distance between pivots 17 300 mm (they are not in bogie center)
Length of intermediate carbodies 23 000 mm
Height of entrance level 1 100 mm

If we discuss about dwell time, we should say, if the full capacity board on each stop. I mean, that full capacity change is only at terminal stations.

Patent is being validated this time and it now in czech only. It is about bogie pivot excentricity which alows greater distance between pivots than distance between bogie centres.

The kinematic gauge of a vehicle with clearance to platform (with clearance increase according to radius) is proven.

Max width at bogie level is 1951mm

http://www.networkrail.co.uk/aspx/11153.aspx

http://www.rssb.co.uk/Library/group...ructure-sic-guide-to-british-gauging-t926.pdf
 

AM9

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St Albans
If we discuss about dwell time, we should say, if the full capacity board on each stop. I mean, that full capacity change is only at terminal stations.

With just 12 double doors for 140+ metres of passenger accomodation length and 800+ passengers compared with 14 double doors on 7 cars' worth of a typical UK SD train with 600 passengers, the dwell time would be longer. That's ignoring the need for passengers to climb or descend stairs inside the train. The proportion of total passengers per station would be the same, just more per train but fewer trains.

Patent is being validated this time and it now in czech only. It is about bogie pivot excentricity which alows greater distance between pivots than distance between bogie centres.

So the 6-wheel articulated offset pivot bogies are unlikely to be motored. That means that drive is resricted to the 4-wheel end bogies, giving no more than 2/7ths of the total weight as adhesive. Not going to be stunning acceleration then.

The kinematic gauge of a vehicle with clearance to platform (with clearance increase according to radius) is proven.

So as the centre of the coach body swings away from the platform, when on the inside of a curve, the train passing on an adjacent track will be fouled or it will need a drastic increase in the 6 foot way.
 

Clip

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That's an impressive drawing though no matter the flaws in it.
 

janplomer

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With just 12 double doors for 140+ metres of passenger accomodation length and 800+ passengers compared with 14 double doors on 7 cars' worth of a typical UK SD train with 600 passengers, the dwell time would be longer. That's ignoring the need for passengers to climb or descend stairs inside the train. The proportion of total passengers per station would be the same, just more per train but fewer trains.
Are you sure? How many seconds will make the difference? The entrance vestibules are large. It's really difficult to correctly estimate. Let's make or find the study how many people board where.
So the 6-wheel articulated offset pivot bogies are unlikely to be motored. That means that drive is resricted to the 4-wheel end bogies, giving no more than 2/7ths of the total weight as adhesive. Not going to be stunning acceleration then.
This study calculate with motor the outer wheelsets of common bogies - using cardan shaft. It gives 10/19 adhesion ratio.
So as the centre of the coach body swings away from the platform, when on the inside of a curve, the train passing on an adjacent track will be fouled or it will need a drastic increase in the 6 foot way.
It is not so hot, the static gauge overthrow is nearly the same as classic vehicle with the same distance between pivots (+/-10mm).
--- old post above --- --- new post below ---

It doesn't fulfill standard gauge, but it respect platform offset according to GI/GN7616 (page 22).
It is clear, that standard gauge must be changed to allow double-deck train service.
 

hwl

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Are you sure? How many seconds will make the difference? The entrance vestibules are large. It's really difficult to correctly estimate. Let's make or find the study how many people board where.

This study calculate with motor the outer wheelsets of common bogies - using cardan shaft. It gives 10/19 adhesion ratio.

It is not so hot, the static gauge overthrow is nearly the same as classic vehicle with the same distance between pivots (+/-10mm).
--- old post above --- --- new post below ---


It doesn't fulfill standard gauge, but it respect platform offset according to GI/GN7616 (page 22).
It is clear, that standard gauge must be changed to allow double-deck train service.

The limiting factor is not the platforms - there are many bridge deck beams (where there is a road under the railway) where the beams are very close to the track - see figure 1 on page 2 of the pdf on the page of the first report I linked to.
Platforms are the easy bit...

The number (and hence cost) of bridges or tunnels requiring modification is unlikely to make a change to the gauge happen soon.


Dwell times. Many busy routes won't have a terminus as the busiest station see Thameslink and Crossrail in their post 2018 states. Also the timetables at busy terminus station may require turnarounds in just 4-6minutes.

The Thameslink train specification (see Siemens class 700 thread) allows doors opens for just 27s in busiest stations during service recovery with probably a change of passengers of circa 1,000 expected hence fewer seats, no arm rests to seat back trays etc. and doors 3 persons wide and 24 doors per train.

The average axle loading is 14.6 tonnes which will get a VERY heavy penalty in track access charges. Network Rail also do not like articulated bogies because of higher track wear. Recently UK EMU stock in service is between 10.5 and 11.5tonnes /axle. New UK stock being delivered for Thameslink and Crossrail will be even lighter at 8.5-9.1tonnes /axle.
 
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LexyBoy

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The importance of the dwell time issue depends on whether these are intended to be Intercity trains or commuter trains - the latter being where capacity is most needed.

It is clear, that standard gauge must be changed to allow double-deck train service.

Indeed - but if you accept that you will have to rebuild all tunnels, bridges, and gantries to allow for the increased height, and realign most of the track, rebuild platforms and move lineside infrastructure (and no doubt other things I am unaware of), then you could just do a bit more to allow standard DD trains to run. The problem with such works is that it rapidly becomes more expensive than building a new line.
 

janplomer

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Prague, Czech Republic
The limiting factor is not the platforms - there are many bridge deck beams (where there is a road under the railway) where the beams are very close to the track - see figure 1 on page 2 of the pdf on the page of the first report I linked to.
Platforms are the easy bit...

The number (and hence cost) of bridges or tunnels requiring modification is unlikely to make a change to the gauge happen soon.
I understand your arguments. I don't presume when would DD trains operate in UK, I have only presented you my design, which makes DD EMU more efficient.


Dwell times. Many busy routes won't have a terminus as the busiest station see Thameslink and Crossrail in their post 2018 states. Also the timetables at busy terminus station may require turnarounds in just 4-6minutes.

The Thameslink train specification (see Siemens class 700 thread) allows doors opens for just 27s in busiest stations during service recovery with probably a change of passengers of circa 1,000 expected hence fewer seats, no arm rests to seat back trays etc. and doors 3 persons wide and 24 doors per train.
I can imagine 6 double-leaf doors per car...

The average axle loading is 14.6 tonnes which will get a VERY heavy penalty in track access charges. Network Rail also do not like articulated bogies because of higher track wear. Recently UK EMU stock in service is between 10.5 and 11.5tonnes /axle. New UK stock being delivered for Thameslink and Crossrail will be even lighter at 8.5-9.1tonnes /axle.
Axle-load is naturally higher, but total weight is lower. Common bogie design is very track friendly. Its friction power (wear level is depend on friction power) is about 25% of standard 2-axle bogies without radial steering.

The importance of the dwell time issue depends on whether these are intended to be Intercity trains or commuter trains - the latter being where capacity is most needed.

Indeed - but if you accept that you will have to rebuild all tunnels, bridges, and gantries to allow for the increased height, and realign most of the track, rebuild platforms and move lineside infrastructure (and no doubt other things I am unaware of), then you could just do a bit more to allow standard DD trains to run. The problem with such works is that it rapidly becomes more expensive than building a new line.
This design had to resolve to focus on height only. Sixfoot and platform offset is fulfilled. Beams and other obstacles within this contour would have to be removed. It is not applicable on all lines, but somewhere yes. Isn't it?
 

najaB

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This design had to resolve to focus on height only. Sixfoot and platform offset is fulfilled. Beams and other obstacles within this contour would have to be removed. It is not applicable on all lines, but somewhere yes. Isn't it?
Yes. On tracks that have been built to a large enough gauge - so HS1 currently and HS2 in a few years.
 
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