My idea for Crossrail extra platforms through central London.

[7ftBroad]

Been thinking ( I do sometimes ), crossrail central station should of been built with more platforms 2 eastbound and 2 westbound. Between stations is fine with 1 track either way. With more platforms loading and in unloading from both side less dwell time and a late train could overtake and get back into position build cost would be saved by running extra services.

 

[Abpj17]

I'm not sure I understand your proposal, and where is all this extra space coming from?

https://en.wikipedia.org/wiki/Crossrail#Eye_of_the_Needle

 

[gordonthemoron]

what about the Barcelona/Munich system where passengers alight oneside of the trains and board the other side?

 

[D365]

One would assume that is rather more costly to achieve with bored tunnels, without being able to dig out a trench.

 

[Ianno87]

Been thinking ( I do sometimes ), crossrail central station should of been built with more platforms 2 eastbound and 2 westbound. Between stations is fine with 1 track either way. With more platforms loading and in unloading from both side less dwell time and a late train could overtake and get back into position build cost would be saved by running extra services.

You should be able to get 24tph "easily" enough anyway through the rolling stock with wide doors/ciculation space enabling rapid boarding and alighting, plus the signalling giving a rapid reoccupation time between trains.

Remember also that 2 x doors on each side slows the dispatch procedure, by having to check one side, then the other, before departure.

Plus another limiting factor is the number of trains you can have in each tunnel ventilation section; no point having lots of platform infrastructrue that can't actually be taken advantage of due to headway limitations between stations.

Furthermore, you wouldn't recover the service (I don't think) by getting trains back in booked order; it'll be more like a tube line where trains will just be switched to another branch instead, or turned back short.

 

[D365]

I must admit to being curious why, in this instance, Munich (and Barcelona) decided that their "Spanish style" platforms are advantageous.

 

[cactustwirly]

I must admit to being curious why, in this instance, Munich (and Barcelona) decided that their "Spanish style" platforms are advantageous.

Having seen it at the height of rush hour, it works really effectively, allowing only a very small dwell time at each station.

 

[Aictos]

I must admit to being curious why, in this instance, Munich (and Barcelona) decided that their "Spanish style" platforms are advantageous.

Simple, it's to speed up boarding and alighting from the trains ie passengers board from one side and alight on the other side.

It's called the Spanish solution to give it's full name and is use in the UK on the London Underground, DLR to name a few and can be seen in use at White City and Loughton on the Central line and Canary Wharf on the DLR.

 

[swt_passenger]

Been thinking ( I do sometimes ), crossrail central station should of been built with more platforms 2 eastbound and 2 westbound. Between stations is fine with 1 track either way. With more platforms loading and in unloading from both side less dwell time and a late train could overtake and get back into position build cost would be saved by running extra services.

Any chance you could edit your title to “Crossrail”? Autocorrect struck again I expect...

 

[AM9]

Simple, it's to speed up boarding and alighting from the trains ie passengers board from one side and alight on the other side.

It's called the Spanish solution to give it's full name and is use in the UK on the London Underground, DLR to name a few and can be seen in use at White City and Loughton on the Central line and Canary Wharf on the DLR.

Loughton is hardly a pinch point for the Central Line. Stratford is much more important yet I think the recent addition of the south-side up platform is to reduce the number of passengers using the subway to get to platform 3 by providing access from the upper concourse. This helps traffic from the Jubilee Line (platforms 13-15), DLR (platforms 16 & 17), The footbridge over the station eastern end and direct entry from the main gateline. I there doesn't seem to be any board or alight differentiation there.

 

[BelleIsle]

what about the Barcelona/Munich system where passengers alight oneside of the trains and board the other side?

Always fun to see the tourists at Marienplatz get out the wrong side then panic as this is no way off the platform.

 

[gordonthemoron]

Always fun to see the tourists at Marienplatz get out the wrong side then panic as this is no way off the platform.

ofcourse there is, you get on the next S-Bahn and exit from the correct side

 

[Busaholic]

Been thinking ( I do sometimes ), crossrail central station should of been built with more platforms 2 eastbound and 2 westbound. Between stations is fine with 1 track either way. With more platforms loading and in unloading from both side less dwell time and a late train could overtake and get back into position build cost would be saved by running extra services.

Thameslink central tunnel would have been an even better place to introduce this, with changeover from overhead to 3rd rail occurring at the platform and then, in case of malfunction, there need be no stacking up of trains. Yes, I know there's no room for these extra platforms, but we are talking pipe dreams anyway, aren't we?

 

[D365]

Aside from Paddington, Canary Wharf and Woolwich, all of the new underground stations on Crossrail are bored excavated, I believe. Has the "Spanish style" solution been implemented in a 250m tunneled station yet? I'm not sure how the new platforms on the Munich "2er Stammstrecke" will be constructed.

 

[swt_passenger]

Aside from Paddington, Canary Wharf and Woolwich, all of the new underground stations on Crossrail are bored, I believe. Has the "Spanish style" solution been implemented in a 250m bored tunnel station yet? I'm not sure how the new platforms on the Munich "2er Stammstrecke" will be constructed.

I think most stations apart from those you already mentioned were excavated and spray concrete lined, rather than bored and lined with segments.

 

[D365]

I think most stations apart from those you already mentioned were excavated and spray concrete lined, rather than bored and lined with segments.

Good point - a simpler question would be whether underground "Spanish style" platforms would make economic sense. The only existing examples in London appear to be above ground.

 

[swt_passenger]

Good point - a simpler question would be whether underground "Spanish style" platforms would make economic sense. The only existing examples in London appear to be above ground.

I was also just thinking about how you’d lay it out efficiently, especially if building at a significant depth. The Crossrail standard seems to be one central concourse, fed from both ends, with multiple cross passages. I guess having four platform faces (2 per track) means vastly more complex access tunnels, more lifts, more escalators and possibly intermediate level transfer concourses? That’s without thinking about deep level interchange to other lines.

 

[rebmcr]

I was also just thinking about how you’d lay it out efficiently, especially if building at a significant depth. The Crossrail standard seems to be one central concourse, fed from both ends, with multiple cross passages. I guess having four platform faces (2 per track) means vastly more complex access tunnels, more lifts, more escalators and possibly intermediate level transfer concourses? That’s without thinking about deep level interchange to other lines.

It could work, with a central concourse for boarding and the side platforms for alighting. The boarding and alighting flows can then be operated as two completely separate stations!

 

[AM9]

I was also just thinking about how you’d lay it out efficiently, especially if building at a significant depth. The Crossrail standard seems to be one central concourse, fed from both ends, with multiple cross passages. I guess having four platform faces (2 per track) means vastly more complex access tunnels, more lifts, more escalators and possibly intermediate level transfer concourses? That’s without thinking about deep level interchange to other lines.

... and just how much benefit would such an expensive add-on as this bring? With 24tph, that's one train every 2.5 minutes of which 30 seconds for arriving, thirty seconds for departing, at least 30 seconds to release/open and close/interlock (slower plug-type) doors, that leaves one minute for passenger alighting/boarding and maybe a bit for a realistic headway. So with two sided access, it might be possible to reduce the alighting/boarding time to 40 seconds, that would as a maximum add three more train per hour. Hardly worth the extra. Extending the trains to the designed maximum of 11 cars would be more effective and probably cheaper. By the time that extra capacity was used up, more 'Crossrails' would already have been considered.

 

[7ftBroad]

Any chance you could edit your title to “Crossrail”? Autocorrect struck again I expect...

It's been changed, thanks

 

[swt_passenger]

... and just how much benefit would such an expensive add-on as this bring? With 24tph, that's one train every 2.5 minutes of which 30 seconds for arriving, thirty seconds for departing, at least 30 seconds to release/open and close/interlock (slower plug-type) doors, that leaves one minute for passenger alighting/boarding and maybe a bit for a realistic headway. So with two sided access, it might be possible to reduce the alighting/boarding time to 40 seconds, that would as a maximum add three more train per hour. Hardly worth the extra. Extending the trains to the designed maximum of 11 cars would be more effective and probably cheaper. By the time that extra capacity was used up, more 'Crossrails' would already have been considered.

I was trying to think how difficult and more expensive it would be, not supporting the idea...

 

[moogal]

It's called the Spanish solution to give it's full name and is use in the UK on the London Underground, DLR to name a few and can be seen in use at White City and Loughton on the Central line and Canary Wharf on the DLR.

Not quite - It's only used by reversing trains in the central platform at White City to get people onto the correct platform to transfer to a following train, the outer ("through") platforms load and unload like any other station. Canary Wharf DLR does not have a particular side for alighting or boarding when using the central platform, doors are enabled on both sides and passengers choose whichever they prefer.

In both of these cases the ability to open doors on both sides is used to make connections with other services rather than to ease congestion. The closest we probably get are the DLR termini at Bank and Tower Gateway, both of which use separate platforms for boarding and alighting.

 

[Ianno87]

Not quite - It's only used by reversing trains in the central platform at White City to get people onto the correct platform to transfer to a following train, the outer ("through") platforms load and unload like any other station. Canary Wharf DLR does not have a particular side for alighting or boarding when using the central platform, doors are enabled on both sides and passengers choose whichever they prefer.

In both of these cases the ability to open doors on both sides is used to make connections with other services rather than to ease congestion. The closest we probably get are the DLR termini at Bank and Tower Gateway, both of which use separate platforms for boarding and alighting.

Tower Gateway is a Spanish solution. Single track with alighting platform one side, boarding the other.

 

[AM9]

I was trying to think how difficult and more expensive it would be, not supporting the idea...

But surely it would only be considered as a method to improve operation and/or increase capacity.
For example, at Stratford, it allowed a significant proportion of passengers to board/alight avoiding the congested pedestrian tunnels under the main platforms. Providing the additional platform was probably cheaper and less disruptive than widening or duplicating the tunnel(s). It probably enable a smoother dwell during the peak once passengers were familiar with the operation of doors on both sides.
The cost impact (and disruption if added into an existing station complex) of subterranean dual platforms would be a major consideration in even initial planning of line capacity. The fact that it may be possible to build such an arrangement wouldn't really figure in a decision not to go that way.
Crossrail specifically has been built despite the many obstructions in its path. The famed 'eye of the needle' feat where the TBM passed within 800mm of the fully operational Northern Line tunnel at Tottenham Court Road was an indication of the difficulties planned for and (thankfully) successfully conquered. Passing under so many deep foundations of sometimes historic and fragile buildings was a high engineering and financial risk enough. Widening the footprint of stations by over 50% may well have put the whole project at risk of cancellation, giving no increase in passenger capacity in the capital at all.

 

[Tim M]

Just consider this. Hong Kong MTR operate at 2 minute or or less headways with 30 second dwell times, each train featuring 8 carriages with 5 doors a side with a capacity of 3000 passengers. Interchange stations have cross platform transfer between lines with timetables arranged to manage passenger flows across the platforms between the trains on each line. Crossrail will probably never approach such capacity requirements.

Oh and by the way, lt was London Underground people who designed the original Mass Transit network in Hong Kong, and is why MTR are respected worldwide in knowing how to move high numbers of people.

 

[Dr_Intoxicated]

One used to be able to alight on both sides on the up line at Ascot (SWR) but last time I was there I see they have put up a fence on the central platform to prevent this. Anyone know why this was done? Was it to aid circulation?

 

[swt_passenger]

One used to be able to alight on both sides on the up line at Ascot (SWR) but last time I was there I see they have put up a fence on the central platform to prevent this. Anyone know why this was done? Was it to aid circulation?

I think modern EMUs (possibly all trains) don’t normally allow doors to open on both sides together.

 

[AndrewE]

But surely that's only the way they are wired and the staff operating instructions. They are just tools, don't forget. "Computer says NO" is not acceptable in infrastructure provision.

 

[30907]

But "safety says NO" is a good reason: allowing alighting/boarding both sides at any station is an added risk for dispatching, and I can see no obvious disbenefit to passengers at Ascot. ISTR it still happens in the Coast bay at Carlisle, but that's the exception.

 

[AndrewE]

But "safety says NO" is a good reason: allowing alighting/boarding both sides at any station is an added risk for dispatching, and I can see no obvious disbenefit to passengers at Ascot. ISTR it still happens in the Coast bay at Carlisle, but that's the exception.

How come it works perfectly well on several modes of transport in the UK then, plus on heavy rail abroad? "Safety says no" is almost always the reply of someone trying to fend off something they hadn't thought of and is not an adequate reply as it is not actually a reason. If the guard has already [safely] closed the alighting door why can't they subsequently cross to the boarding side and do that one?