SWT 10 car platforms

[Surreyman]

I noticed all the platforms on the stations between Hinchley Wood - Guildford 'Newline' are in the process of having their platforms extended to 10 cars, all in line with the timescale.
Guildford is due to have Platforms 1 (bay) and 2 extended to 10 car length (I am sure platform 2 can already take 12 cars?).
In order to extend Bay Platform 1, some fairly drastic alterations will need to be made to the track layout at the northern end, I noticed some 'made up' track panels stacked in this area, anyone know anymore details of when & how?

 

[swt_passenger]

I have no details, but there are also intended to be alterations to the sidings on the down side to allow for stabling longer trains and/or extra trains (for the increased number of units generally following the 458/5 and 456 introduction).

PS - Just found a list of platform capacities for SWT, and P2 is shown as 12 car in the down direction only , with SDO required for 450s and 444s in the up direction. So it may be that the work to make P2 up direction available for 10 car trains is fairly straightforward - especially if the junctions need re-positioning to give access to a lengthened P1 anyway...

 

[DynamicSpirit]

PS - Just found a list of platform capacities for SWT, and P2 is shown as 12 car in the down direction only , with SDO required for 450s and 444s in the up direction. So it may be that the work to make P2 up direction available for 10 car trains is fairly straightforward - especially if the junctions need re-positioning to give access to a lengthened P1 anyway...

I'm curious - how can a platform possibly take trains of a certain length if travelling in one direction, but only take shorter trains if travelling the other way? The length of a platform is kinda fixed isn't it?

 

[61653 HTAFC]

I'm curious - how can a platform possibly take trains of a certain length if travelling in one direction, but only take shorter trains if travelling the other way? The length of a platform is kinda fixed isn't it?

Signal positions, I think...

 

[swt_passenger]

I'm curious - how can a platform possibly take trains of a certain length if travelling in one direction, but only take shorter trains if travelling the other way? The length of a platform is kinda fixed isn't it?

Signal positioning with respect to junctions just beyond the platform end is the usual reason. Many of these layouts were originally built for working in the conventional direction only.

 

[Surreyman]

Signal positioning with respect to junctions just beyond the platform end is the usual reason. Many of these layouts were originally built for working in the conventional direction only.

Platform 2 is usually used weekdays as a terminating platform for 455 units (up to 8 car).
At weekends it is often used as a down platform for Portsmouth/Haslemere trains up to 12 cars.
No idea why (P4 is the main down through platform).

 

[455driver]

Platform 2 has the starting signal (GD750) set a long way from the end of the platform so that it is positioned clear of the first set of points to access the up Cobham line (and then the points onto the up main line towards Woking).
If a 12 coach train arrives in platform 2 from the down Cobham (or down Main line) it will be on the platform okay but the rear cab will be a long way beyond GD750 so it will not be able to return in the up direction as it will be foul of the track circuit/ points.
--- old post above --- --- new post below ---

Platform 2 is usually used weekdays as a terminating platform for 455 units (up to 8 car).
At weekends it is often used as a down platform for Portsmouth/Haslemere trains up to 12 cars.
No idea why (P4 is the main down through platform).

Only on a Sunday is P2 used for the down Pompey trains because the Cobham and Epsoms can share platform 1 as they are hourly and it is easier for the pompey passengers as the main entrance is on platform 2 so they dont have to use the subway/overbridge to get to/from the train.

 

[DynamicSpirit]

Signal positioning with respect to junctions just beyond the platform end is the usual reason. Many of these layouts were originally built for working in the conventional direction only.

Ah, that makes sense, thanks!

 

[Peter Mugridge]

I have been wondering why at Motspur Park ( yes, I know that's on a different route but it's still part of the SWT 10 car project! ) the extensions are slightly staggered?

 

[61653 HTAFC]

I have been wondering why at Motspur Park ( yes, I know that's on a different route but it's still part of the SWT 10 car project! ) the extensions are slightly staggered?

Again I'd imagine this is down to signal positions. It's generally simpler on two-track routes to extend platforms in the trailing direction, as this minimises the impact on signalling- if the signalling won't need to be altered to allow for extensions by trains continuing to stop in the same position as previously- this will reduce the associated costs of the extension work and may make the difference between a programme being viable or not.

Of course I'm coming at this as an amateur, so there's likely other members who can put rather more detail into the explanation!

 

[Surreyman]

Travelling home on sunday evening, I noticed a 12 car 450 in platform 3 at Woking, thats the (relatively new, well a few years old), east facing bay platform used by terminating stopping services to Waterloo weekdays.
I have wondered why the service is not run by 450s all the time?
The route serves a well heeled commuter area, so first class would be popular, bringing in more revenue, secondly all the stations served already have 12 car platforms so 12 car trains could run in peaks.
Presumably its all down to rolling stock availability?
Could things change when 458/450 swops/cascadeds take place on Windsor lines?
Maybe its lack of space in the sidings at Guildford, although I believe extensions are due?

 

[455driver]

Travelling home on sunday evening, I noticed a 12 car 450 in platform 3 at Woking,

I have wondered why the service is not run by 450s all the time?

Because there are not enough 450s available during the week plus on arrival at Waterloo that train then forms a service to Guildford via Cobham, which then forms a service to Waterloo via Epsom before heading back to Woking.

They cannot really have the service as standard class only on Monday to Friday and first/standard class at weekends also the leasing costs of the 450 are much higher than the 455s which is why the Weybridge/Hounslow services are 455s on a weekend as there are sets spare.

secondly all the stations served already have 12 car platforms so 12 car trains could run in peaks.

When did they extend Earlsfield, Clapham jn (P10 and 11), Vauxhall and Waterloo P1-4?
There are some 12 coach 450 services in the peaks now but they run fast to/from Surbiton and Waterloo.

 

[Peter Mugridge]

Again I'd imagine this is down to signal positions. It's generally simpler on two-track routes to extend platforms in the trailing direction, as this minimises the impact on signalling- if the signalling won't need to be altered to allow for extensions by trains continuing to stop in the same position as previously- this will reduce the associated costs of the extension work and may make the difference between a programme being viable or not.

Of course I'm coming at this as an amateur, so there's likely other members who can put rather more detail into the explanation!

I thought that but they've seemingly moved every other signal on that route ( and made a big slew of the track at Stoneleigh ) and at Motspur Park the side of the stagger that is towards the level crossing is the side approaching the crossing...



Edited to add:

Since posting the above I have been given the reasons off list; I am just checking a couple of minor details and will post up the reply in full, probably tomorrow, when I have the answers to my minor queries...


Edited to add:

Here is what I was sent off list:

Re: the posts on RailUK forums about the 10 car scheme and Motspur Park I can advise on this.

The next poster states about signal sighting - I can advise in this instance it is nothing to do with this at all. In fact the London bound signal (W404) was moved to assist with the platform lengthening! It is all to do with the current regulations for minimum widths of platforms - presumably under 'elf & safety legislation. With the current track layout it was not possible to extend the platform at one end only and be within the regulations, so the plan evolved to what is on the ground now - the up platform has been lengthened slightly at both ends whereas the down platform is only being lengthened at the London end. This may also have something to do with the signal for the level crossing and the associated track circuits but I cannot state this for sure.

Worcester Park is a straight forward lengthening of both at the London end, as is Ewell West. However I've been told that as EWW is a listed building the platform extensions will be in brick and not the flatpack system used elsewhere. Stoneleigh was a different kettle of fish, as due to the footbridge and station buildings at the c/e it was not possible to extend the platforms there, so the up line was slewed slightly westwards so the platform could be extended at the l/e.

The posts by 455 driver about Guildford P2 sum up the situation accurately.

The situation at Raynes Park where Platforms 1 & 2 taper to a pencil width would certainly not be permitted as a new build these days - things were different in them days!