Reading Station improvements

[whole diary]

[ironstone11]

OK here are gradients from Theale to Reading station (extracted from the signalling plan dated November 2010):

F=Falling Gradient in direction of Travel
R=Rising Gradient in Direction of Travel
O/B=Overbridge
U/B=Underbridge
m=Metres


Reading West Station Platform (Middle) to Reading Station (Via Westbury Lines)

5822F for 22m to Oxford Road U/B
671R for 38m Over Oxford Road O/B to Oxford Road Junction Points
330F for 112m
194F for 150m
250F for 472m to Reading Triangle Upper Points
110F for 42m
147R for 73m
304F for 40m to Westbury Junction (Main Line Side)
LEVEL to Reading Station (Main Line Side)
LEVEL through Reading Station Platforms



I^ll put the Main Line in a separate post.

Many thanks for that.

Analysing the figures I conclude that the Westbury chord descends by 3m in the up direction between Reading West Stn and Reading Stn.

The freight feeder lines descend from Reading West Stn. by about 3m to the viaduct box and then ascend by approx 3m to Reading Stn.

If you go down 3 and then up 3 you are not at the same level as just going down 3, so something is wrong with my reasoning.

This implies that between the freight feeder viaduct box and Reading Stn. the relief lines ascend by 3m. I will have to check the distance, but this seems an unlikely gradient for a Brunel railway.   

[paul7575]

I sort of question the fact, why the mainline is a flyover with Freight trains that have to go up a gradient below the mainlines...

The first version of the Reading West plan was to put the mainlines under the others.  The mains on viaduct option was a later decision. The basic reason the mains underpass  didn't happen was that they would have had to close Cow Lane.

Probably far easier to build the present design.  The design statement on the planning website suggests the height change for the feeder lines from the box towards the station is less than 2 metres, (1850 mm) so one can only hope they know what the freight trains are capable of...

Paul

[paul7575]

I passed another trailer with three canopy sections about half an hour ago, it was heading north on the Winchester bypass.  I wonder where they are being built?

PS - A trailer with another 3 sections being reversed outside the main entrance at 2130, possibly those I saw earlier...

Paul

[ironstone11]

There's been a lot of activity joining up the West end of  P11, visible by zooming into the left-hand edge of the picture from camera 02/2. It's hard to make out, especially with a ballast train on P9, but the rail crane has been there presumably to move the pieces of track.

I notice from Realtime Trains that after 1200 tomorrow (Mon), both P10 & 11 are in use. After that, P10 is used by just one train per day, the 0604 Southampton - Manchester XC^▸ (Cross Country Trains (franchise)) service. I guess that means that the western end of the platform is used while work continues on the eastern end. Temporary buffer stops halfway along?

[SandTEngineer]

Continued: Here are gradients from Tilehurst to Reading station (extracted from the signalling plan dated November 2010):

F=Falling Gradient in direction of Travel
R=Rising Gradient in Direction of Travel
O/B=Overbridge
U/B= Underbridge

Tilehurst Station to Readng West Junction (Main Lines)

1320F average from Tilehurst Station to Scours Lane Junction
3614F for 445m
1760F for 136m
2682F for 341m
85R for 621m (Reading West Junction and Mains Flyover Reading West Curve and Reading Festival Lines)

Readng West Junction to Reading Station (Main Lines)

730F for 538m
93F for 536m (Passing over Mains Flyover Up Reading Feeder Main and Down Reading Feeder Relief)
LEVEL for 256m to Caversham Road U/B
1463F for 429m to Reading Station Platforms
LEVEL through Reading Station Platforms

Tilehurst Station to Readng West Junction (Relief Lines)

1320F average from Tilehurst Station to Scours Lane Junction
3614F for 1579m from Scours Lane Junction to Reading West Junction

Readng West Junction to Reading Station (Relief Lines)

3614F for 529m
420R for 169m
730R for 402m
LEVEL to Westbury Line Junction
LEVEL to Reading Station
LEVEL through Reading Station Platforms

Reading West Junction to Westbury Line Junction (Down Reading Festival Line)

209R for 177m (passing under the Mains Flyover)
72R for 384m (Passing over Mains Flyover Up Reading Feeder Main and Down Reading Feeder Relief)
93F for 506m (Connection to Up Westbury at Westbury Line Junction)

Health Warning: This data is extracted from a copy of the signalling plan that is 3 years old and may therefore not fully represent the arrangements currently being constructed.  It is therefore listed as a guide only.

[paul7575]

I notice from Realtime Trains that after 1200 tomorrow (Mon), both P10 & 11 are in use. After that, P10 is used by just one train per day, the 0604 Southampton - Manchester XC^▸ (Cross Country Trains (franchise)) service. I guess that means that the western end of the platform is used while work continues on the eastern end. Temporary buffer stops halfway along?

I think it's more likely that nothing will be using the platform and that's a typo in the underlying data.  It has happened before, a few XC services were shown using incorrect platforms after the big Easter changes - a number of XC through services were wrongly shown reversing in P7, which was impossible by that stage...

The listings for the 2nd of September show XC using P10 during most of the day, I'd bet on it not happening.

Paul

[stuving]

If you go down 3 and then up 3 you are not at the same level as just going down 3, so something is wrong with my reasoning.
 

I agree that any three routes between A and B should have the same height change, subject of course to the tolerance of these figures. So something (literally) does not add up.

I can add a piece of data from non-railway sources: the spot heights on an old OS^▸ (Ordnance Survey) map are 137 ft on Oxford Road, and 126 ft on Caversham Road, both near enough at the bridge. So given that the bridges are similar and hence so is the road to railway offset, you would expect a fall about 3.3 m in each railway route between those points - again plus a suitable tolerance.

[ellendune]

In the overall scheme of things I expect it's the manufacturer of the roof sections that has the 'steady stream' production line, and at the station they are being fitted in anything but a steady stream - (notwithstanding this weeks overnight activity on P8/9).  So eventually they might have to be delivered to 'somewhere' to make room at the factory, even if the station isn't ready to accept them.

But on the other hand perhaps the P10/11 panels were going to be fitted the weekend after they arrived but something else, such as a mobile crane, was cancelled at the last minute?  Or was the weather forecast wrong, or were the steelwork supports delayed unexpectedly?

Paul

Looking at P10 it appears to me that if any further canopy panels were added they would seriously overhang the track (until the track and platform is realigned in the next few weeks). Would this be a reason why the modules cannot be fitted yet?

[ironstone11]

If you go down 3 and then up 3 you are not at the same level as just going down 3, so something is wrong with my reasoning.
 

I agree that any three routes between A and B should have the same height change, subject of course to the tolerance of these figures. So something (literally) does not add up.

I can add a piece of data from non-railway sources: the spot heights on an old OS^▸ (Ordnance Survey) map are 137 ft on Oxford Road, and 126 ft on Caversham Road, both near enough at the bridge. So given that the bridges are similar and hence so is the road to railway offset, you would expect a fall about 3.3 m in each railway route between those points - again plus a suitable tolerance.

Yes thanks, that's useful confirmation that my figures for the Westbury chord are about right.

The explanation lies in the figures for the relief lines. If I use these:-

Reading West Junction to Reading Station (Relief Lines)

3614F for 529m
420R for 169m
730R for 402m
LEVEL to Westbury Line Junction
LEVEL to Reading Station
LEVEL through Reading Station Platforms

The relevant ones being 730R for 402m which starts at the freight feeder box.

This gives a rise to the station of 0.55m and at an upward gradient of 1:730 and within reasonable tolerances, a similar height to the route via the Westbury chord.

So the answer to the original question is that there is no problem. If a train stops on the freight feeder it is on a downhill slope anyway (towards Reading) and when joining the relief lines encounters a 1:730 upward gradient.

QED.

[stuving]

The relevant ones being 730R for 402m which starts at the freight feeder box.

This gives a rise to the station of 0.55m and at an upward gradient of 1:730 and within reasonable tolerances, a similar height to the route via the Westbury chord.

So the answer to the original question is that there is no problem. If a train stops on the freight feeder it is on a downhill slope anyway (towards Reading) and when joining the relief lines encounters a 1:730 upward gradient.

QED.

I don't follow. What I see in the relief line figures is that they run almost level along the embankment, so are only 0.55 m down level with the feeder line box. But the feeder lines are "virtually at grade", i.e. 3 m down at that point.

The main lines fall 6.5 m from the top of the viaduct, but less than half of this happens from the feeder box - so the feeder lines must be below the relief lines to pass below the main lines on the viaduct.

[insider]

There's been a lot of activity joining up the West end of  P11, visible by zooming into the left-hand edge of the picture from camera 02/2. It's hard to make out, especially with a ballast train on P9, but the rail crane has been there presumably to move the pieces of track.

I notice from Realtime Trains that after 1200 tomorrow (Mon), both P10 & 11 are in use. After that, P10 is used by just one train per day, the 0604 Southampton - Manchester XC^▸ (Cross Country Trains (franchise)) service. I guess that means that the western end of the platform is used while work continues on the eastern end. Temporary buffer stops halfway along?

PLATFORM 10 will be OUT OF USE both starting signals will be covered over, Platform 11 (up main loop) will be in use. Signalling / route availability will be identical to that currently of platform 10.

To confirm that is.

Up trains: from Up Westbury or Up Main, permissible working allowed.

Down trains: No access from Kennett Bridge end, however a train can enter from UM/UW and reverse to DM or DW

Speed:25mph

Only minor difference is that platform 11 will be fully A/B working as technically 10 was never split.

[Gordon the Blue Engine]

Re the Up Down Feeder Relief line gradient issue which I was ratcheting up.

I'm happy to acknowledge that now we know more about the lengths and extents of the gradients that will be encountered by up stone trains between Oxford Road Junction and the station via the Up Down Feeder, it is probably not a mathematical certainty that such a train, if brought to a stand at the signal on the Up Down Feeder line just before it joins the DR, would not be able to restart.

However, I think it would be a brave signaller who tried it!  So I think these trains will still if at all possible be given a clear run from Southcote Junction and through the station not just for the reasons Oxman mentioned earlier, but also to avoid the risk of a train being unable to restart - or worse, just managing to move far enough to foul the DR. 

edit:  "Up Feeder" description corrected to "Down Feeder" as per Stuving below.

[stuving]

Re the Up Feeder line gradient issue which I was ratcheting up.

I'm happy to acknowledge that now we know more about the lengths and extents of the gradients that will be encountered by up stone trains between Oxford Road Junction and the station via the Up Feeder, it is probably not a mathematical certainty that such a train, if brought to a stand at the signal on the Up Feeder line just before it joins the DR, would not be able to restart.

However, I think it would be a brave signaller who tried it!  So I think these trains will still if at all possible be given a clear run from Southcote Junction and through the station not just for the reasons Oxman mentioned earlier, but also to avoid the risk of a train being unable to restart - or worse, just managing to move far enough to foul the DR. 

That raises another point - how would such an issue be dealt with now? After all, this problem of heavy freight trains and gradients isn't new. I guess that in the past it was down to a signaller's local knowledge, but has that now been replaced by something more systematic? After all, it would not be hard to put the trains' vital statistics into the suitable program and find out exactly which routes it can cope with (at some given adhesion). I could probably do it in Excel, given the time.

That presumably would be based on the worst-case stopping points, since surely in the new capacity-improved conflict-reduced layout more trains should operate as pathed - non-stop from loop to loop?

Oh, and if you look closer you will see that it is called the Down Reading Feeder Relief line - not Up, despite being on the left of the Up Reading Feeder Main. I presume that's because it branches off the Down Relief. Of course they are both bi-directional.

[ironstone11]

The relevant ones being 730R for 402m which starts at the freight feeder box.

This gives a rise to the station of 0.55m and at an upward gradient of 1:730 and within reasonable tolerances, a similar height to the route via the Westbury chord.

So the answer to the original question is that there is no problem. If a train stops on the freight feeder it is on a downhill slope anyway (towards Reading) and when joining the relief lines encounters a 1:730 upward gradient.

QED.

I don't follow. What I see in the relief line figures is that they run almost level along the embankment, so are only 0.55 m down level with the feeder line box. But the feeder lines are "virtually at grade", i.e. 3 m down at that point.

The main lines fall 6.5 m from the top of the viaduct, but less than half of this happens from the feeder box - so the feeder lines must be below the relief lines to pass below the main lines on the viaduct.

Yes, you may well have a point.

[paul7575]

Discussions yesterday about the possible use of P10 are now academic, as not only are the signals bagged out of use as mentioned earlier, but almost the entire length of the temporary pre-fabricated platform structure has been removed.  Where the temporary surface IS still present, (ie towards the London end where it tapered away to nothing), the track has been removed completely.

I'll try and upload a few pictures later on once I've reduced their file size a bit...

Paul