Cambridge South new station construction progress.

[William3000]

Can anybody confirm what the line speed will be through Cambridge South following opening - albeit I appreciate the overwhelming majority of trains will stop here?

My understanding is that it used to be 90mph (145km/h) through the station but platforms 2 and 3 will be reduced to 80mph (130km/h) with platforms 1 and 4 50mph (80km/h).

 

[mr_moo]

In the Up direction (from Cambridge heading South) the speed will be 70mph (currently 90) from just South of Cambridge station.
Just North of the new station the Up Main steps up to 80mph. The Up loop is 60mph.
Further South the linespeed steps up to 90mph near where Dukes LC was.
Shepreth Branch junction becomes 50 mph (from 30 today).

In the Down direction, from the Royston lines, Shepreth branch junction is again 50mph (from 30 today). The Down Main has an 80mph board just after the Down Royston merges in. The up loop is 60mph.
The 80 continues to join the existing 80mph today.
The Down Slow remains unchanged at 40mph.

Whilst this feels counterintuitive, the rationale is partly due to decreased signal spacing, which gives better headways. There are more signals going in than being removed, so the distances between them are getting smaller.

 

[Magdalia]

My understanding is that it used to be 90mph (145km/h) through the station

For GN trains this was only ever theoretical, because of approach control at Cambridge station going down and at Shepreth Branch Junction going up. I think the fastest I've ever got to on GN trains is less than 70 mph. West Anglia EMUs regularly went through Shepreth Branch Junction at 90 mph with a clear road.

Whilst this feels counterintuitive, the rationale is partly due to decreased signal spacing, which gives better headways.

This will be good, the current headways on the down road are dire. I've experienced the crawl from Shepreth Branch Junction to Cambridge when following something else far too many times.

What will make the big difference is the 50 mph line speed at Shepreth Branch Junction to/from the GN, though decreased signal spacing will help too. Do we end up with 5 signal sections between Shepreth Branch Junction and Cambridge instead of the current 4?

 

[neill]

Couple of updates from today. This morning work was in full swing on the end wall for platform 2/3. By the time I was heading home this evening the wall was finished. It looks like there is a gap on the left side for some steps in future.

I think the conduit is now complete along P2/3, maybe except for around the foundations for the staircase which haven’t been poured yet. I wonder if the plan in near future is to move the signal cabling currently running through the P1/2 trackbed into the new conduit so that the trackbed can be completed.

 

[Nicholas Lewis]

Couple of updates from today. This morning work was in full swing on the end wall for platform 2/3. By the time I was heading home this evening the wall was finished. It looks like there is a gap on the left side for some steps in future.

I think the conduit is now complete along P2/3, maybe except for around the foundations for the staircase which haven’t been poured yet. I wonder if the plan in near future is to move the signal cabling currently running through the P1/2 trackbed into the new conduit so that the trackbed can be completed.

Nice to see a railway job making such rapid progress

 

[Silenos]

This will be good, the current headways on the down road are dire. I've experienced the crawl from Shepreth Branch Junction to Cambridge when following something else far too many times.

What will make the big difference is the 50 mph line speed at Shepreth Branch Junction to/from the GN, though decreased signal spacing will help too. Do we end up with 5 signal sections between Shepreth Branch Junction and Cambridge instead of the current 4?

Allowing for this, do we have any inkling what overall impact stopping everything at Cambridge South will have on the Ely and Lynn timetables? I’m assuming a small increase in journey time.

 

[arb]

Allowing for this, do we have any inkling what overall impact stopping everything at Cambridge South will have on the Ely and Lynn timetables? I’m assuming a small increase in journey time.

There is a thread discussing the timetables here.

One of the posts in that thread suggests that "Logically, the waits at Cambridge will be reduced by the stopping time for required for Cambridge South thus meaning no further time table work needed". I'm not convinced that's true for every train, but the other thread shows that it is in theory possible for some.

 

[Silenos]

There is a thread discussing the timetables here.

One of the posts in that thread suggests that "Logically, the waits at Cambridge will be reduced by the stopping time for required for Cambridge South thus meaning no further time table work needed". I'm not convinced that's true for every train, but the other thread shows that it is in theory possible for some.

Thanks. I’d missed that one.

 

[neill]

Some photos from midday today. The last sections of P1 are now in place and over on the west building the stairs have arrived and are being installed.

Edit: Added some drone shots taken from Hobson's park.

 

[chappers]

Having worked on this project up until a couple of weeks ago, I really enjoy seeing the progress updates.

We knew the building would fly up, and sure enough it’s really starting to come together. Great to see it all taking shape

 

[Nodding Cat Ch]

The steel frames are popping up on the Great Kneighton side of the new station.
Platforms are looking a lot more obvious. No changes with the tracks, at the station site, or further up at Shepreth Junction.

 

[neill]

Here is an end of week update. Quite a bit of progress on the park side building this week - the lift tower is now finished and the main stairs and first floor are in. Looks like the roof beams are going to be lifted in place soon.

I think there has been a bit more prep for the bridge/stairs/lift on the island but no signs steelwork is imminent.

Suspect this will get merged with previous post, but here are some Sunday afternoon updates.

The most interesting development is that the roof beams are being lifted in. The wood (glulam?) beams look rather smart. Also there seems to be a sheet piling retaining wall under construction at the south end of P4 - anyone have any idea why?

I have other photos from some of the other work sites this weekend - there must have been getting on for 50 people at work this afternoon(!).

 

[mr_moo]

For GN trains this was only ever theoretical, because of approach control at Cambridge station going down and at Shepreth Branch Junction going up. I think the fastest I've ever got to on GN trains is less than 70 mph. West Anglia EMUs regularly went through Shepreth Branch Junction at 90 mph with a clear road.


This will be good, the current headways on the down road are dire. I've experienced the crawl from Shepreth Branch Junction to Cambridge when following something else far too many times.

What will make the big difference is the 50 mph line speed at Shepreth Branch Junction to/from the GN, though decreased signal spacing will help too. Do we end up with 5 signal sections between Shepreth Branch Junction and Cambridge instead of the current 4?

Heading Northbound coming from Royston, CA119, near Hauxton AHB, becomes 4 aspect.
From there going north the signals are basically re-done entirely to fit the new layout.
Currently, there is CA123 - 141 - 143 - 145. CA145 is just South of Long road bridge.
In future there will be one additional signal in that section.
From Shelford, CA99, the signal just North of Shelford station, is unchanged (although Cambridge re-signalling are giving it a banner). Next after that is currently CA141 as above.
In future, there will be one additional signal for that direction too.

Signal CA145 is re-numbered (I'm not sharing the new numbers yet) and moves slighlty but not much.
Between there and Cambridge station there will be one additional signal on each of the Down Slow and Down Main. The station entry signals, CA147 and CA149 today, move right up to the S&C.
The limit of shunt and reversing boards will all move towards Cambridge as well, to allow for the additional signal block and relocated signals.

Couple of updates from today. This morning work was in full swing on the end wall for platform 2/3. By the time I was heading home this evening the wall was finished. It looks like there is a gap on the left side for some steps in future.

I think the conduit is now complete along P2/3, maybe except for around the foundations for the staircase which haven’t been poured yet. I wonder if the plan in near future is to move the signal cabling currently running through the P1/2 trackbed into the new conduit so that the trackbed can be completed.

Fantastic pictures as always neill. Thank you do much.
The gap is indeed for steps down to track in future.

The cable conduit is almost complete - we've got a few tweaks to do plus all the access chambers.

We are getting closer to building track on the East side too, so yes, that cable trough will be coming out soon. A lot of the cables have already been diverted into platform 4 actually, so there's not loads left in there to move now.

 

[neill]

Thanks @mr_moo. There was a lot going on elsewhere yesterday as well. I was surprised that work was able to continue despite the wind which was blowing quite a gale even though you can’t see that in the photos.

I got around a few other spots where work was happening, and here are a few more photos. The first two are from the Shelford junction footbridge. The first looking south shows a cable being laid which finished just a few meters further on. The second is looking north from the bridge and shows the progress on the OLE equipment and formation for the extended junction. Looks like the old OLE should be able to come out soon. The next one is of some interesting OLE structure that was being worked on between Long road and Hills road (closer to the long road end). I think the whole thing is new rather than a replacement but not sure what it does.

There was some more work going on closer to the station - again looked like on the OLE but I wasn’t able to get any good photos due to the work on the busway fence at the moment.

 

[Steve Harris]

@neill Do you mean Shepreth Branch Junction ? As there hasn't been a Shelford Junction in my lifetime (and I used to work in Shelford box).

 

[William3000]

He does. I guess colloquially some may call it Shelford junction as it’s in Shelford but it is as you say Shepreth Branch junction. Presumably Shelford junction was to the south of Shelford where the former Haverhill and Sudbury line branched off?

 

[neill]

He does. I guess colloquially some may call it Shelford junction as it’s in Shelford but it is as you say Shepreth Branch junction.

Yes, I guess I do!

Meanwhile looks like some folks have had a busy night. Most of the roof beams are on now.

 

[mr_moo]

We did have several periods where the crane was unable to work due to the wind, but we had monitoring ongoing and were starting and stopping as wind speeds allowed. We still got a fair amount done as per your last photo!

It was indeed avery busy weekend. I'll ost more about what else happened soon.

 

[Magdalia]

Presumably Shelford junction was to the south of Shelford where the former Haverhill and Sudbury line branched off?

That's right, see picture here:

Shelford Junction Signal Box

Photo by the late Jack Ray. Date not known, probably early-mid 1960s.

www.flickr.com

Shelford Junction Signal Box

I was surprised that work was able to continue despite the wind which was blowing quite a gale even though you can’t see that in the photos.

We did have several periods where the crane was unable to work due to the wind, but we had monitoring ongoing and were starting and stopping as wind speeds allowed.

You should have tried it on Magog Down: I think it was the first time ever that I needed to pedal going downhill into Stapleford.

After that experience I returned by the DNA path. Fortunately the people working at Shepreth Branch Junction had their feet firmly on the ground.

 

[Steve Harris]

That's right, see picture here:

Shelford Junction Signal Box

Photo by the late Jack Ray. Date not known, probably early-mid 1960s.

www.flickr.com

In the 1980's that box was simply known as 'Shelford' and the crossing gates had been replaced by electric barriers !

The neighbours to Shelford Box were Granhams Road and Whittlesford (all the boxes went at a similar time), of course they all went when Cambridge PSB took over control of the area.

 

[William3000]

In the 1980's that box was simply known as 'Shelford' and the crossing gates had been replaced by electric barriers !

The neighbours to Shelford Box were Granhams Road and Whittlesford (all the boxes went at a similar time), of course they all went when Cambridge PSB took over control of the area.

Foxton still has a box on the Shepreth branch - hopefully when it is redundant it will be retained rather than demolished.

 

[mr_moo]

That's right, see picture here:

Shelford Junction Signal Box

Photo by the late Jack Ray. Date not known, probably early-mid 1960s.

www.flickr.com

You should have tried it on Magog Down: I think it was the first time ever that I needed to pedal going downhill into Stapleford.

After that experience I returned by the DNA path. Fortunately the people working at Shepreth Branch Junction had their feet firmly on the ground.

Wow! It was quite impressive and we were worried initially that we wouldn;t get much done at all but thinkfully the wind allowed us some time.


Here's some impressive pics of the station and its progress over the last week. This is the West side building.



Other works involved the decommissioning of the hot axle box detector and reomval of a storage cabinet down near Sheptreth branch junction, to clear the way for the future Down Royston, which we dug out the area and prepared formation for:



There was also much OLE work undertaken, mainly focussed at Hills road or Long road.


And here's a bit of fun/interest for you too:
View attachment WhatsApp Video 2024-04-07 at 18.00.29.mp4

 

[jammmmmsssssss]

What's the thing in the video for?

 

[swt_passenger]

What's the thing in the video for?

Isolating or switching 25kV supplies to the overhead wires. It’s relatively large scale stuff because all the usual insulation clearance distances have to be met between the live and earthed parts.

 

[jammmmmsssssss]

Isolating or switching 25kV supplies to the overhead wires. It’s relatively large scale stuff because all the usual insulation clearance distances have to be met between the live and earthed parts.

Thanks

 

[swt_passenger]

Thanks

No problem. What I’m never sure of is why they sometimes do this sort of switching at high level above the overheads, but on some other installations it seems to be done in containerised buildings at ground level alongside the track. Perhaps one of our electrification boffins could tell us?

 

[59CosG95]

No problem. What I’m never sure of is why they sometimes do this sort of switching at high level above the overheads, but on some other installations it seems to be done in containerised buildings at ground level alongside the track. Perhaps one of our electrification boffins could tell us?

Now this is where the devil really is in the detail!
At some switching locations (but not all), you have the containerised buildings:

• FSs (Feeder Stations - almost always with Neutral Sections);
• TSCs (Track Sectioning Cabins/Cabinets);
• MPTSCs (Mid-Point TSCs - always with Neutral Sections);
• ATFSs (Auto-Transformer FSs);
• ATSs (Auto-Transformer Site - only switches the ATF);
• SATS (Sectioning ATS - switches both ATF & main OLE);
• MPATSs (an ATF variant of the MPTSC).

Most of these have switches similar to the video above, with newer ones having a "switch farm"; a dedicated compound with motorised switches on structures separate from the railway.
Older installations have them on the same masts.

At other locations, you typically have a manually operated switch controlled from ground level by a long rod running up the mast; the handle is padlocked in a box to prevent those with nefarious purposes accessing it. When the handle is turned, the rod rotates and opens/closes the switch - most are two-position (Open/Closed) but some three-position (Open/Closed/Earthed) ones exist.
These locations are typically at strategic junctions in complex areas; a club which Cambridge South seems to be joining.

(Most of the TSCs/FSs and their ilk listed above also have manual switches in the event the motorised ones don't work, or just for routine use.)

 

[Nicholas Lewis]

Wow! It was quite impressive and we were worried initially that we wouldn;t get much done at all but thinkfully the wind allowed us some time.


Here's some impressive pics of the station and its progress over the last week. This is the West side building.

View attachment 156011View attachment 156012View attachment 156013View attachment 156014View attachment 156015View attachment 156016View attachment 156017View attachment 156018View attachment 156019

Other works involved the decommissioning of the hot axle box detector and reomval of a storage cabinet down near Sheptreth branch junction, to clear the way for the future Down Royston, which we dug out the area and prepared formation for:

View attachment 156020

There was also much OLE work undertaken, mainly focussed at Hills road or Long road.
View attachment 156022View attachment 156023

And here's a bit of fun/interest for you too:
View attachment 156021

Nice to see a railway job making very rapid progress almost by the day

 

[mr_moo]

The most interesting development is that the roof beams are being lifted in. The wood (glulam?) beams look rather smart. Also there seems to be a sheet piling retaining wall under construction at the south end of P4 - anyone have any idea why?

I have other photos from some of the other work sites this weekend - there must have been getting on for 50 people at work this afternoon(!).

Roof - Yep, glulam timber.

Sheet piles - this is for an excavation down to a gas main. We're not diverting this one, but instead are applying strengthening to the pipe by applying a metal casing to the outside of the pipe. I'll have some photos in a few weeks time.

Nice to see a railway job making very rapid progress almost by the day

Thank you.

 

[swt_passenger]

Roof - Yep, glulam timber.

[…]

Thank you.

Glulam from “glued laminated“, ie it’s not a newly discovered variety of hardwood…