Four track for Filton Bank - ongoing discussion

[whole diary]

[tramway]

Firstly apologies to Graham for disrupting your breakfast the other day, but thanks for sorting out my login issue.

From a regular user on the route, the bridge span looks like a single structure. It also looks like there is still some way to go before the supporting structures are going to be ready, some concrete pouring still to do.

A route that was 4 track not that long ago the amount of work to bring it back to engineering requirements today is quite frankly huge. Some of the biggest work looks to have been the underpinning work south of narroways. Subsidence in the area has been an issue for a number of years, hopefully now sorted.

Filton station work progresses but not entirely sure even now what the final layout will be.

Anyway Hi to everyone.

[Bmblbzzz]

As coincidence would have it, I was also on Stapleton Road yesterday – on my way to and from Ikea! I got a Variera, which sounds like a nasty disease but actually bears a slight resemblance to an arched bridge, sort of, once you've got it together, if you squint a bit. Oh and some sylt... which sounds like it should be from Stockholm's harbour but is in fact jam. I did consider taking a photo of the big concrete ramp thing, but I'm glad I didn't because FT,N! has not only photographed it better than I would have but described it more accurately as well.

[Bmblbzzz]

I can confirm that the Filton 4 Tracking Project signalling scheme has made passive provision for a new 4 platform station at Ashley Hill.

Four platforms? That seems to run counter to the idea of having two fast through lines and two for stopping trains. Good to have it there, though. And good to have the whole thing there, seconding its bargainness!

Good news! I suppose the four platforms adds flexibility in case one of the slower lines is closed.

Yes, it does. I was surprised though. And if at Ashley Hill, albeit only passively, maybe also at Stapleton Road? Would make more sense there to enable changing between lines?

[stuving]

I can confirm that the Filton 4 Tracking Project signalling scheme has made passive provision for a new 4 platform station at Ashley Hill.

What does that involve? I mean, does a station actually need any signals, points, or anything of the kind? I though not.

Is it rather just an indication that, should anyone feel inclined in the future to build a station, that is the most likely place for it, so please try not to put any stuff there (not just signals) that would have to be moved later?

[SandTEngineer]

I can confirm that the Filton 4 Tracking Project signalling scheme has made passive provision for a new 4 platform station at Ashley Hill.

What does that involve? I mean, does a station actually need any signals, points, or anything of the kind? I though not.

Is it rather just an indication that, should anyone feel inclined in the future to build a station, that is the most likely place for it, so please try not to put any stuff there (not just signals) that would have to be moved later?

I was only quoting what is stated on the Signalling Scheme Plan (SSP).  I take passive provision in that context as meaning "don't put anything signalling or telecommunications related here" and nothing that might be civil engineering related (e.g. this is the best physical place for a new station).

[grahame]

I was only quoting what is stated on the Signalling Scheme Plan (SSP).  I take passive provision in that context as meaning "don't put anything signalling or telecommunications related here" and nothing that might be civil engineering related (e.g. this is the best physical place for a new station).

One of the reasons quoted for the astronomic price for putting a track alongside the disused platform at Westbury has been "because there are lots of signalling cables buried there" - so no passive provision was made.  On the other hand, when we have challenge about cables being laid at present where a loop line would go at Chippenham (also to do with the old platform there, where we were promised passive provision), we have been told they could be moved very easily if need be.  I am struggling to understand the difference between the Westbury and Chippenham situations, and suspect that the difference is in the message that the infrastructure people want the community to hear ...

[SandTEngineer]

I think the main cable route to Westbury Panel passes that side of the station so 'lots and lots' of cables in the way.  At Chippenham, following the signalling re-control, there are likely to be a maximum of 4 cables in the way.

[TonyK]

Word reaches me of track being laid somewhere around Lockleaze. My camera and I are out of Bristol for a frustrating couple of weeks.

[johnneyw]

Just a thought but could this be part of correcting the slew made to the lines after reducing to two tracks? The slew will need to be corrected at some time in order to make room for returning to four tracks and this might be how they do it with minimum line disruption.

[SandTEngineer]

The Signalling Scheme Plan shows some track slewing at the 1 1/2 mile post between Lawrence Hill and Stapleton Road stations.

[TonyK]

I'll check soon, but I'm out of town until 18 April.

[Bmblbzzz]

Some photos from Constable Road. Not good quality I'm afraid, FT,N!'s will be much better.

[Red Squirrel]

Some photos from Constable Road...

Went and had a squizz at this just now. What may not be immediately apparent from the photos is the height difference between the old and the new: I'd take a stab that the old track is 700-800mm higher. Looking south from the bridge, it is looks like the old track will need to be lowered as well as slewed - which leads me to wonder whether they plan to dig out all the old stuff and build a new bed for it. Anyone know? Seems odd otherwise, given that as I understand it the new stuff we can see going in will be the local (i.e. slow) lines...

[SandTEngineer]

Some photos from Constable Road...

Went and had a squizz at this just now. What may not be immediately apparent from the photos is the height difference between the old and the new: I'd take a stab that the old track is 700-800mm higher. Looking south from the bridge, it is looks like the old track will need to be lowered as well as slewed - which leads me to wonder whether they plan to dig out all the old stuff and build a new bed for it. Anyone know? Seems odd otherwise, given that as I understand it the new stuff we can see going in will be the local (i.e. slow) lines...

As I have said quite a few times on this forum now the WR doesn't do FAST^▸ (Federation Against Software Theft), SLOW or LOCAL lines  .  They are MAIN and RELIEF lines.  The new ones in the photographs will be the RELIEF lines and the existing ones become the MAIN lines.....   The new formation switches over from the RELIEF to the MAIN lines at approximately the 2 3/4 mile post (a short distance south of where the photographs were taken).

A new DOWN MAIN to DOWN RELIEF single lead junction is going to be installed in the foreground of the photograph, and the signal in view (BL1586) disappears as part of that work.  There will also be a new Up RELIEF to UP MAIN single lead junction in the far distance of the photograph partly under the road bridge.  Hence the gaps in the plain line track installation.  The two new junctions will be used by trains to/from BRISTOL PARKWAY (accessed from the MAIN lines at FILTON ABBEY WOOD station) that need to stop at STAPLETON ROAD and/or LAWRENCE HILL stations (with platforms only on the RELIEF lines).

[grahame]

As I have said quite a few times on this forum now the WR doesn't do FAST^▸ (Federation Against Software Theft), SLOW or LOCAL lines .  They are MAIN and RELIEF lines. ...

I totally understand that "main" and "relief" are a tradition that goes back to Marc Brunel.   And that the term "slow" has negative connotations.  "Main" and "relief" strike me as odd when some station platforms are only on the relief lines; the feeling from the names is that trains should primarily run on the main lines and only switch to the relief ones for capacity reasons, and not because the stops are only on the reliefs!

I like the way that King's Cross to Barbican and Moorgate had the "Widened lines". Perhspa we should call the 2 new tracks being added up Filton Bank the "Widened lines" too, with the old lines designated the "Metropolitain lines" as MetroWest will be using them, with platforms only on that pair.