Ashley Down station construction updates

[AndrewE]

Passengers between South Wales and Bristol reminded to check before travelling ahead of essential upgrade works in the Severn Tunnel

Trains will be diverted or replaced by buses between Friday 9 and Sunday 18, and on Sunday 25 June, as Network Rail works around the clock to renew the tracks in the Severn Tunnel.

www.networkrailmediacentre.co.uk

That's very interesting, thanks, I shall look out for a talk on the selection process - and I would love to hear how the tin is to be applied. I can't imagine that electro-plated tin will be anywhere thick enough, and "tin-plate" production for food cans must be either extinct or completely unable to deal with railway-sleeper thickness metal. More questions than answers!
(I wonder whether suitably selected or treated timber would be the best option? I thought that steel sleepers were only chosen as a cheap alternative to timber where the ballast still had a limited life and a full deep-dig relay could be postponed.)
A

 

[zwk500]

That's very interesting, thanks, I shall look out for a talk on the selection process - and I would love to hear how the tin is to be applied. I can't imagine that electro-plated tin will be anywhere thick enough, and "tin-plate" production for food cans must be either extinct or completely unable to deal with railway-sleeper thickness metal. More questions than answers!
(I wonder whether suitably selected or treated timber would be the best option? I thought that steel sleepers were only chosen as a cheap alternative to timber where the ballast still had a limited life and a full deep-dig relay could be postponed.)
A

Aren't steel sleepers problematic on electrified lines that use the running rails as part of the return current? Not sure why Tin-covered ones would be much better though. Mildly surprised they haven't gone for a Recycled plastic option like they did with the Newark Crossing a few years ago.

 

[fgwrich]

Aren't steel sleepers problematic on electrified lines that use the running rails as part of the return current? Not sure why Tin-covered ones would be much better though. Mildly surprised they haven't gone for a Recycled plastic option like they did with the Newark Crossing a few years ago.

I believe the resin / plastic sleepers are still considered to have a limited lifespan which doesn’t match that of concrete or hardwood yet, though of course the latter is being phased out where possible due to environmental reasons. Are any in use in an environment as busy as or as hard working as the Severn Tunnel?

 

[zwk500]

I believe the resin / plastic sleepers are still considered to have a limited lifespan which doesn’t match that of concrete or hardwood yet, though of course the latter is being phased out where possible due to environmental reasons. Are any in use in an environment as busy as or as hard working as the Severn Tunnel?

Interesting. I thought the lifespan was one of the selling points of using the plastic sleepers for Newark. Although Newark FC sees lower numbers of trains it must take a hammering from 125mph North-South and heavy freight east-west hammering the diamonds on their way through.

 

[Ashley Hill]

Didn’t the Avon valley line have recycled plastic sleepers somewhere?

Aren't steel sleepers problematic on electrified lines that use the running rails as part of the return current?

Isn’t tin an excellent conductor?

 

[zwk500]

Isn’t tin an excellent conductor?

This is part of my confusion - perhaps it's a tin-alloy that is non-conductive, or being a coating of a non-conductive material means whatever problems all-metal sleepers cause aren't as big an issue. I guess we'll find out soon enough...

 

[contrex]

This is part of my confusion - perhaps it's a tin-alloy that is non-conductive, or being a coating of a non-conductive metal means whatever problems all-metal sleepers cause aren't as big an issue. I guess we'll find out soon enough...

Are there any non-conductive metals?

 

[zwk500]

Are there any non-conductive metals?

typo for material. There are metals with extremely poor conductivity but you wouldn't be making sleepers of them.

 

[Annetts key]

Tin is a far better conductor than steel. In regards to steel sleepers, they do have pads and biscuit insulators so that they are compatible with track circuited areas elsewhere (unless these are a different design to those used elsewhere).

Also, most of the tunnel suffers from mineral water, not salt water. Even if the water was 100% pure, the damp atmosphere will promote corrosion.

Exactly the same problem exists in tunnels that are nowhere near any sea.

 

[Mag_seven]

Discussion in this thread should be kept to Ashley Down new station. If anyone wants to discuss aspects of the forthcoming Severn tunnel works then please use this thread:

Bristol - Severn Tunnel closed June (and to Cardiff 10-11 June)

It appears lines will be closed between Patchway and Severn Tunnel Junction, Friday 9th June and Monday 12th - Sunday 18th plus following Sunday 25th June On weekend of 10th and 11th June appears the closure will extend through Newport to Cardiff with buses from Cardiff to Bristol area As a...

www.railforums.co.uk

thanks all

 

[Snow1964]

The visuals of the new station are on link, only 2 of the 4 lines are getting platforms, not sure how long the new platforms are, but plans seem to show an area beyond ends of 'island' platform reached by stairs. It is on site of old Ashley Hill station.

The construction statement says platforms will be on approx 40 (20 per platform) 10m long CFA (continuous flight auger) piles, plus another 12 CFA piles for footbridge foundations. The line is on an embankment so is made ground. The platforms will be trestle sections on the piles lifted in by crane.

https://pa.bristol.gov.uk/online-applications/files/184383577256775810153B1E35232DAC/pdf/21_03523_RA-PROPOSED_VISUALS-3002176.pdf

If link won't open, they are on Bristol City Council planning under reference 21/03523/RA

Sadly doesn't look to be most comfortable station to wait for a train ever built as plans mention perch seats, with little protection from weather on the exposed location.

 

[zwk500]

The visuals of the new station are on link, only 2 of the 4 lines are getting platforms, not sure how long the new platforms are, but plans seem to show an area beyond ends of 'island' platform reached by stairs. It is on site of old Ashley Hill station.

Platforms are 126m long, according to Railway Technology:

The Ashley Down station will include two platforms, which will be 126m long, and capable of taking five-car trains. A footbridge will join the two platforms with lifts.

Ashley Down Railway Station, Bristol, UK

Ashley Down railway station is the first of three new stations planned to be built as part of the wider MetroWest Phase 2 project.

www.railway-technology.com

If you look at the General Arrangement drawings, one of them (it's also in the transport statement) has 10m interval markings on the tracks which confirm the length as being halfway between 120m and 130m.

The areas off the ends of the platforms accessible by stairs appear to be staff-only facilities for maintenance access.

 

[Snow1964]

Platforms are 126m long, according to Railway Technology:

The areas off the ends of the platforms accessible by stairs appear to be staff-only facilities for maintenance access.

I do wonder about the 5car idea that GWR operates, only really works properly when there are both a 3car and a 2car available to be coupled (which is far from guaranteed with the very stretched Bristol area turbo fleet).

126m is also marginally short if a 5car IET needs to call during disruption. Can't imagine they would build a mix a 2car and 3car EMUs if line gets electrified so seems daft that they don't just go for platforms nearer 150m to allow 6car working for flexibility and future proofing. I assume 126m is cost saving for now whilst other stations are restricted to 5car

 

[zwk500]

I do wonder about the 5car idea that GWR operates, only really works properly when there are both a 3car and a 2car available to be coupled (which is far from guaranteed with the very stretched Bristol area turbo fleet).

126m is also marginally short if a 5car IET needs to call during disruption. Can't imagine they would build a mix a 2car and 3car EMUs if line gets electrified so seems daft that they don't just go for platforms nearer 150m to allow 6car working for flexibility and future proofing. I assume 126m is cost saving for now whilst other stations are restricted to 5car

Regarding an IET, you'd turn them at either Parkway or Temple Meads. If the line was electrified something like a 5-car 730 would fit, being 5x24m long. I agree it would have been nice to have platforms long enough for 6x23m but at the same time the space is very limited, and the only got more length would have been to shorten or remove one of the staff cabins at either end of the half-island.

 

[Annetts key]

The visuals of the new station are on link, only 2 of the 4 lines are getting platforms, not sure how long the new platforms are, but plans seem to show an area beyond ends of 'island' platform reached by stairs. It is on site of old Ashley Hill station.

The construction statement says platforms will be on approx 40 (20 per platform) 10m long CFA (continuous flight auger) piles, plus another 12 CFA piles for footbridge foundations. The line is on an embankment so is made ground. The platforms will be trestle sections on the piles lifted in by crane.

https://pa.bristol.gov.uk/online-applications/files/184383577256775810153B1E35232DAC/pdf/21_03523_RA-PROPOSED_VISUALS-3002176.pdf

If link won't open, they are on Bristol City Council planning under reference 21/03523/RA

Sadly doesn't look to be most comfortable station to wait for a train ever built as plans mention perch seats, with little protection from weather on the exposed location.

What I find most interesting is that in order to do this, they are having to dig through the remains of the previous upside platform. A lot of which still existed before they started work!

Oh, and at least on the upside, it’s part/edge of a hill. Browse Google street view to see (or search “28 station road, Ashley Down, Bristol, BS7 9LB”). Link goes to a street view that shows the very visible slope of the road near to the railway line and the site of the previous station and now the site where the new station is being constructed.

 

[jazzy]

Network Rail Western's Twitter account is now providing good updates while this work goes on:

We've ploughed on with track work at Ashley Down station throughout today. All of the sleepers are into their final position, ensuring the track will align with the platforms - which we'll soon start building. It's tough work in hot weather #BristolRailRegen

https://twitter.com/networkrailwest/status/1665405382468988929

 

[Ashley Hill]

I understood that when quadrupling took place provision was made for the platforms so why the need to relay the relief lines now?

 

[jazzy]

I understood that when quadrupling took place provision was made for the platforms so why the need to relay the relief lines now?

I’d assumed that the ‘new’ / main pair of lines would have provided for the platforms but it’s the ‘old’ / relief lines that will serve the platforms and I assume their position wasn’t changed during the four tracking exercise. I believe they’re being relaid to minimise the gap between platform and carriages.

 

[Annetts key]

After the route was de-quadded in the mid 1980s, some parts of what were (and are now again) the relief lines were realigned. This is partly why the downside embankment needed so much work doing before they could add the main lines back in, when four tracking it.

Hence, presumably the Filton Down Relief line had not been moved/realigned again, even though due to the bridge and former island station access, it can’t have been moved too far.

It’s also possible that the track needed a new formation anyway and it’s more logical to do this work before constructing a new station.

It’s also unusual for the rails to be removed if all that is happening is the line being slewed slightly.

I don’t think the Filton Up Relief was too far from its original alignment, because as I said earlier, a lot of the upside platform was still there. Demolition was cancelled during the days of BR because the contractor that started the work hit the (still in use at the time) cable route! Hence it stayed like that until recently.

 

[AndrewE]

Those sleepers look decidedly scruffy... Have they been re-used from elsewhere (which I have no problem with at all,) or just been hanging round for ages waiting to be laid?

 

[swt_passenger]

Those sleepers look decidedly scruffy... Have they been re-used from elsewhere, or just been hanging round for ages waiting to be laid?

They’re the sleepers that were already there, surely? They’ve decided to lift them temporarily and relay them rather than simply slewing them onto a new alignment?

 

[The exile]

Those sleepers look decidedly scruffy... Have they been re-used from elsewhere (which I have no problem with at all,) or just been hanging round for ages waiting to be laid?

Don’t know whether it’s the same lengths - but there’s been a whole load of sleepers and rails on the platform of the old Filton station for ages.

 

[AndrewE]

They’re the sleepers that were already there, surely? They’ve decided to lift them temporarily and relay them rather than simply slewing them onto a new alignment?

Ah! Innocent me imagined that re-quadrupling would mean 2 brand-new tracks! Maybe the fasts have been completely relaid and the sleepers re-used on the slows. I still think that's no bad thing...

 

[Annetts key]

Don’t know whether it’s the same lengths - but there’s been a whole load of sleepers and rails on the platform of the old Filton station for ages.

I don’t know about the sleepers on the platforms (not been that way for a bit) but the sleepers on the down side cess of the Filton Down Main at the same location, look like new sleepers, not used ones.

Ah! Innocent me imagined that re-quadrupling would mean 2 brand-new tracks! Maybe the fasts have been completely relaid and the sleepers re-used on the slows. I still think that's no bad thing...

For most of the length, only the missing bits were new (however all lines received new track where points were removed or added). Hence at this location, the new track is the Up Main and the Down Main. The existing tracks became the Up Relief and the Down Relief.

 

[The exile]

Ah! Innocent me imagined that re-quadrupling would mean 2 brand-new tracks! Maybe the fasts have been completely relaid and the sleepers re-used on the slows. I still think that's no bad thing...

It did mean two brand new tracks (though the originals swapped sides just above Narroways Hill Junction) but that was completed pre-covid.

 

[Sean Emmett]

I am bit perplexed as to what is going on! Last week of May some concrete structures had been built between the relief and main lines, which I assumed were for the footbridge. Pic from 27/05/23.

But when I had a look on Saturday morning they had gone! Pic from 03/06/23.

At least we've now got a sign.

 

[jazzy]

The bulk of the track work at Bristol's new Ashley Down station is done with just some fine tuning to do next week.With sleepers fully aligned we installed the top stone & compacted it with tamping trains. Focus now shifts to platform construction #BristolRailRegen

https://twitter.com/networkrailwest/status/1665734613980033026?s=20

 

[Sean Emmett]

Platforms are in! Pics from today, from public road.

Also did video Thu eve from passing train, but probably too chunky for here.

 

[Ashley Hill]

Quick to build,will it be quick to open?

 

[jazzy]

Quick to build,will it be quick to open?

Given the advanced state of the platforms and that the bridge is due to be installed in late August, I'd be very interested to understand why a 2024 opening date is being indicated? What tasks will need to take place and why will they take so long?