Reading Station improvements

[whole diary]

[ellendune]

I had thought that a route might have been left in via P8, but if you take the other one out you cannot turn a XC^▸ (Cross Country Trains (franchise)) Birmingham to Southampton very easily.  I suppose that clearing the other line out of the way means that the turnout where the line from P8 and the line from the reliefs join can be removed and it is simple task to slew the connection over  when the possession starts.

[paul7575]

Does anyone know the fundamental reason why a down train from P8 therefore cannot follow the up direction route in reverse to reach the up Westbury (so via the 763 crossovers and the down main as described in stuving's extract from the NCN posted above)?

I suppose just because the track is there it doesn't mean there is a proper signalled route over it?

Paul

[ellendune]

"Proposed G1 Network Change Notice" of March 2014:

In preparation for the Christmas commissioning there is a need to undertake track formation work in the Westbury Line Junction vicinity.

Is the formation work something underneath that kink (see photo I linked to a few posts back). Is there some chamber or other structure under there that needs sorting before they can lay track on it?

 

[stuving]

Does anyone know the fundamental reason why a down train from P8 therefore cannot follow the up direction route in reverse to reach the up Westbury (so via the 763 crossovers and the down main as described in stuving's extract from the NCN posted above)?

I suppose just because the track is there it doesn't mean there is a proper signalled route over it?

Paul

Hardly. It's the normal route from P8 to the DM combined with the normal route from P9 to the DW. So even if they are avoiding using P8 to revers XC^▸ (Cross Country Trains (franchise)) trains to the south, it must work (and there is at least one Newbury service going that way next week.)

As to what they are actually doing now, it's not too obvious. There's P3 being built, and much ballast shovelling around P7, and loads of men and machines in evidence - but not much old track has gone. It looks as if they have dragged that link from P8 across to the old end of P7, but I imagine it's only fit for short-term engineering use. It looks as if the space vacated is being populated with sleepers for the new track straight from P9 to the DM on the viaduct. There does seem to be a set of points in there too, but it's hard to see why - the final position of that junction of P8 and P9 is a lot further west.

(Edit: second picture added)

[ellendune]

It looks as if the space vacated is being populated with sleepers for the new track straight from P9 to the DM on the viaduct. There does seem to be a set of points in there too, but it's hard to see why - the final position of that junction of P8 and P9 is a lot further west.

Thanks for the photos.

If the points being constructed is for the junction of P8 to the DM (and I cannot see why they should not be) then the layout from P1,2,3,7,8 looks pretty much complete as shown on the drawing posted earlier http://www.firstgreatwestern.info/coffeeshop/index.php?topic=6405.msg163179#msg163179. Only the points to the festival line and some plain line connections to be added.  I assume the P8 to Up Westbury connection still needs to be made (in plain line) when the connection from P10 to the Westbury is taken out.

[paul7575]

Have done some more digging, and found the Gioconda signalling brief for the 2013 layout.  

Signal TR240 at the country end of P8 only provided for 3 possible routes.  

Main aspect to Down Westbury via Up Westbury and crossover towards signal TR344.
Main aspect and position 4 'feather' to the Down Main via the temporary crossover 763 and signal TR44 on the down main.
Position Light (the two small white lights) towards Up Westbury and exit via TR542 (another position light towards the triangle sidings.)  

The position light route doesn't count for passenger service, so the signal can only authorise two routes. I think that's the main stumbling block - I expect they cannot just arbitrarily 'join' two signalled routes half way along.

It's always possible that those few services shown as using P8 towards the Westbury route are errors in the underlying data that RTT^» (Real Time Trains - website) is displaying.  This has happened before when significant changes occurred, they showed impossible platforming for a few days until it was corrected.

Paul

[stuving]

I had expected that everything north of the current line from P7 to the Down Westbury would have to be replaced this time round, on the grounds it's all old stuff. Topologically it's not going to change so much, and maybe some bits are in fact new (or renewed) and I've forgotten.

P8 (after the Festival Line splits off) will join P9 about as far past Caversham road as that bridge is beyond the end of P8. So on second thoughts the lines now appearing may be final - that foreshortening again.

[ellendune]

I had expected that everything north of the current line from P7 to the Down Westbury would have to be replaced this time round, on the grounds it's all old stuff. Topologically it's not going to change so much, and maybe some bits are in fact new (or renewed) and I've forgotten.

P8 (after the Festival Line splits off) will join P9 about as far past Caversham road as that bridge is beyond the end of P8. So on second thoughts the lines now appearing may be final - that foreshortening again.

I think you will find that over various weekend possessions most of it has already been replaced in the last year or so. 

[stuving]

Have done some more digging, and found the Gioconda signalling brief for the 2013 layout.  

Signal TR240 at the country end of P8 only provided for 3 possible routes.  

Main aspect to Down Westbury via Up Westbury and crossover towards signal TR344.
Main aspect and position 4 'feather' to the Down Main via the temporary crossover 763 and signal TR44 on the down main.
Position Light (the two small white lights) towards Up Westbury and exit via TR542 (another position light towards the triangle sidings.)  

The position light route doesn't count for passenger service, so the signal can only authorise two routes. I think that's the main stumbling block - I expect they cannot just arbitrarily 'join' two signalled routes half way along.

It's always possible that those few services shown as using P8 towards the Westbury route are errors in the underlying data that RTT^» (Real Time Trains - website) is displaying.  This has happened before when significant changes occurred, they showed impossible platforming for a few days until it was corrected.

Paul

So far today all the services routed via P8 to Reading west have been switched to P7, and future ones are also being moved over, so maybe that is how it WILL work out. In terms of rules, of course, it's more subtle than that. There were previously two routes to the same destination - direct (ahead at TR240, with no feather) and right and then left later. If I've identified the rules that apply (unlikely, I know, but still ...) they could not be signalled with one common feather as the speed limits are too different. So it's easier to suppress one of them. However, in terms of how many routes can be signalled there is no problem. And now all routes out of P8 must observe the lower speed limit anyway. So I imagine the issue is more one of programming the route-setting function at Didcot, plus all the procedures for checking, re-checking, notifying all, drivers, and sundry etc. Which may well not be worth the effort when P7 is not exactly rushed off its feet and it's only for ten days anyway. And there's always P9 as well.

An interesting test will come tomorrow, when 2K52 - 12:12 to Newbury is still shown in P8, while P7 is occupied by an extra - 1Z31 - The Cathedrals Express (12:10), steam-hauled from Newington to Bristol (and needing to water at Newbury Racecourse).

[paul7575]

As of this morning there is only one route out of P8 (looking towards the west), as there's a baulk of timber strapped to the rails half way along the 'kinked bit'.   From the end of P8 it looks very much like they just need to slew that 'kinked' track by a similar amount to the left of a theoretical straight line and it will line up nicely with the points to join the down main.

I took a XC^▸ (Cross Country Trains (franchise)) service back down to Basingstoke, and tried to photo what's going on the other side of Caversham Rd bridge, but they didn't really help much, later I'll try and get something off the phone video I took going towards Reading...

The straight ahead route from P8 now has the points in position to reach the down main, with the left route leading to a short stub of line which includes the trailing points coming in from P7, and then just as far as the next facing points that will either route straight ahead to the Festival line or 'bear left' to remain on the up Westbury (in the down direction). There's little more than a few feet beyond that third set of points, then ballast.

First pic below just shows the timber blocking the route, (below the gantry) and the current view of Westbury Line Jn beyond, so nothing to add to the earlier pics above really.

Second pic is the furthest points taken from the train window, they're sitting between the finished down Westbury, and the temporary route of the up Westbury towards the P9/10 crossovers etc.  So (if I'm right) from left to right in that view it is down Westbury, future up Westbury, future Festival line.

Paul


 

[stuving]

An interesting test will come tomorrow, when 2K52 - 12:12 to Newbury is still shown in P8, while P7 is occupied by an extra - 1Z31 - The Cathedrals Express (12:10), steam-hauled from Newington to Bristol (and needing to water at Newbury Racecourse).

To tidy up that (not entirely serious) observation - what other platforms are available? Well, at the same time of 12:10 (within timing allowances) P9 is occupied by 1L50 Cheltenham-Paddington. And why is that not in P10 or P11? P10 has 1M42 Bournemouth-Manchester Piccadilly, and P11 has 1O84 Newcastle-Southampton Central.

Which all looks rather odd, given that running from P9 towards Paddington means crossing over at Kennet Bridge, as the crossovers at Reading East Jn are going in over Christmas. P11 (but not P10) has commonly been used for southbound XC^▸ (Cross Country Trains (franchise)) services in the past, though how that route gets indicated I'm not sure (no feathers on T1715). I'm sure the signallers will sort something out ...

[ellendune]

It looks like almost all of the difficult track-laying will be done on the P7/8 routes before Christmas - it will just need joining up with plain track, changing the signalling and commissioning.  That will leave them more time to look at the P9/10/11 which they will have to start from scratch as they have no space to do the preparatory work.  I assume they will recover the temporary connction from P8 to P9 later. 

[paul7575]

... P11 (but not P10) has commonly been used for southbound XC^▸ (Cross Country Trains (franchise)) services in the past, though how that route gets indicated I'm not sure (no feathers on T1715). I'm sure the signallers will sort something out ...

T1715 has a small theatre box below the main aspects that shows either M for down Main or W for down Westbury.  When I say small it is much smaller than many I've seen elsewhere, more like one of those CD^▸ (Capital Delivery)/RA indicators, i.e. a letter box shape, and not designed for long distance reading.

I believe the reason there are no 'feathers' is that it is a movement normally made only by reversing trains, so there is less need for advance warning.   It is one of those minor inconsistencies about the whole set up - the vast majority of other signals use feathers as I'm sure you've noticed.

Paul

 

[paul7575]

It looks like almost all of the difficult track-laying will be done on the P7/8 routes before Christmas - it will just need joining up with plain track, changing the signalling and commissioning.  That will leave them more time to look at the P9/10/11 which they will have to start from scratch as they have no space to do the preparatory work.  I assume they will recover the temporary connction from P8 to P9 later. 

There are short sections of track already in situ.  If you can visualise the new crossover that replaces the temporary one at the end of P8/P9 that you've mentioned,  then the points at the other end are there with a length of track that must be the new down main.

I've marked what appears to be the eventual new down main from P9 on a cropped copy of the earlier photo, it isn't as clear as the in use track as it is practically submerged in the new ballast.

If you follow the line of that track you'll see a couple of white boxes?   Those are the power units for extending lighting rigs, but coincidentally they are at either end of the points I mentioned.  Unfortunately there's a redundant signal gantry that prevents the direct view, but if anyone is passing on a train they'll act as reference points to where I'm trying to describe!

Paul

[stuving]

To tidy up that (not entirely serious) observation - what other platforms are available? Well, at the same time of 12:10 (within timing allowances) P9 is occupied by 1L50 Cheltenham-Paddington. And why is that not in P10 or P11? P10 has 1M42 Bournemouth-Manchester Piccadilly, and P11 has 1O84 Newcastle-Southampton Central.

Which all looks rather odd, given that running from P9 towards Paddington means crossing over at Kennet Bridge, as the crossovers at Reading East Jn are going in over Christmas. P11 (but not P10) has commonly been used for southbound XC^▸ (Cross Country Trains (franchise)) services in the past, though how that route gets indicated I'm not sure (no feathers on T1715). I'm sure the signallers will sort something out ...

Thinking about it, wasn't the signal at the country end of P10 (TR.240) taken out when the platform was rebuilt and not replaced? In which case using P10 for an XC reverser implies that the new signal (T.1715) is now in place, and is being used "because it's there".