Nuneham Viaduct shut - Didcot- Oxford

[edwin_m]

I agree - telephoto lens distortion etc --- but still!

Looking at #255, the total drop is somewhere around twice the rail height, or about 300mm.

One good thing is it is effectively 2 single tracks running parallel, and far enough apart that working on one track shouldn't stop work on adjacent track. Plenty of room for a protective fence down the middle.

A pier has sunk, but not clear if still sinking, or stopped moving. There is potentially a chance deck can be jacked up (or at least one of them, whichever side is least bad) and packed short term.

However, no trains can run until the central girder and at least one of the side ones has been lifted back to the correct level. I think it's an abutment rather than a pier, but not sure if that makes it better or worse.

== Doublepost prevention - post automatically merged: 5 Apr 2023 ==

I'm not sure you can argue that the "fragmentation" of the railways since privatisation has led to this. After all the Turbos in question were built and delivered to BR spec.

And they had mechanically identical couplers to the Sprinter fleet, but were made electrically incompatible, allegedly so Regional Railways couldn't pinch NSE's units.

 

[Saj8]

Both lines are bi directional from Appleford junction all the way to Wolvercote junction. However, between Appleford junction and Kennington junction, they are one long signalling section in the wrong direction, so it would be just one train in the 8 mile section at a time. Line speed is 60 in the wrong direction. Realistically, you'd be looking at 2tph each way tops using only one line. Arguably better than nothing, and that assumes its even possible to work on half the bridge at a time, which I can't see being the case.

 

[zwk500]

Both lines are bi directional from Appleford junction all the way to Wolvercote junction. However, between Appleford junction and Kennington junction, they are one long signalling section in the wrong direction, so it would be just one train in the 8 mile section at a time. Line speed is 60 in the wrong direction.

Thanks for the confirmation

Realistically, you'd be looking at 2tph each way tops using only one line. Arguably better than nothing,

Definitely better than nothing, offering Crosscountry/GWR and freight 1tph each would be massive.

and that assumes its even possible to work on half the bridge at a time, which I can't see being the case.

But yes, I doubt that this approach would be viable.

 

[webweasel]

I would have thought the fix would be to bore a couple of piles either side as close to the abutment as possible on the bridge side, pilecap, steel goalpost and then hydraulic jack the bridge span back to level, then demolish and contiguous pile the abutment, rebuild with new bearings and re-lay the track bed.

The question is, can they install the goalpost and stabilise it, re-lay the track, then demolish and rebuild the abutment when the Botley bridge is down later in the year?

 

[Geogregor]

How about blowing the ancient junk up and simply building a proper modern bridge?

I know, I'm grabbing my coat...

 

[Horizon22]

Use an 80x instead. There will be at least one spare due to the absence of the Oxford fast.

Well yes they could replace it with that but would require a bit of timetable rewriting if you wanted to run the Paddington - Bedwyn and remove the 387 service AND the shuttle. Plus units still needed for the Oxford - Worcester section.

== Doublepost prevention - post automatically merged: 5 Apr 2023 ==

Just spotted a slightly bigger problem - Bedwyn's platforms are only 120m, so an 80x doesn't completely platform. You'd need a very precise stopping point to get just enough of the nose over the edge to get all doors on the end (possible, might be just paperwork but could be a bit more involved). Of course, I'm half expecting @Taunton to come along and tell me that the mark of a good Western man was to stop the front door on a sixpence anyway and that an Old Oak man would do it with his eyes shut

5-cars ran the Bedwyn service throughout the lockdown.

 

[bspahh]

How about blowing the ancient junk up and simply building a proper modern bridge?

I know, I'm grabbing my coat...

It took 6 months to replace the bridge across the Great River Ouse at Ely Dock Junction when a freight train derailed in 2007.

 

[MarkyT]

How about blowing the ancient junk up and simply building a proper modern bridge?

I know, I'm grabbing my coat...

It's not VERY old. According to this page https://thames.me.uk/s01530.htm the current structure is the third bridge on the site, built in 1929. There are short brick-built viaduct sections on land at both sides of the river, the one at the south end being the longer one. From the photo up-thread, the curve suggests the problem is with the south bank support for the southerly steel span. I wonder if its foundation has been scoured out by recent floodwater?

 

[43enjoyer]

It's not VERY old. According to this page https://thames.me.uk/s01530.htm the current structure is the third bridge on the site, built in 1929. There are short brick-built viaduct sections on land at both sides of the river, the one at the south end being the longer one. From the photo up-thread, the curve suggests the problem is with the south bank support for the southerly steel span. I wonder if its foundation has been scoured out by recent floodwater?

Perhaps inclined to believe the 1929 date is false due to this tweet but who knows https://twitter.com/markannand/status/1643579162077134850?s=46&t=ZKMwD5hfXUI6osfYZa0v5w

 

[Geogregor]

It's not VERY old. According to this page https://thames.me.uk/s01530.htm the current structure is the third bridge on the site, built in 1929. There are short brick-built viaduct sections on land at both sides of the river, the one at the south end being the longer one. From the photo up-thread, the curve suggests the problem is with the south bank support for the southerly steel span. I wonder if its foundation has been scoured out by recent floodwater?

Yes, the bridge is from 1929 but apparently it reuses earlier elements (embankments? parts of support structure?). At least that's what people in this thread are saying.

In general you can only patch up things up to a point. Especially if environment is changing around the structure.

 

[swt_passenger]

It's not VERY old. According to this page https://thames.me.uk/s01530.htm the current structure is the third bridge on the site, built in 1929. There are short brick-built viaduct sections on land at both sides of the river, the one at the south end being the longer one. From the photo up-thread, the curve suggests the problem is with the south bank support for the southerly steel span. I wonder if its foundation has been scoured out by recent floodwater?

The BBC report‘s video (no longer available) actually showed there is only an embankment on the south side, all the way up to the abutment.

 

[webweasel]

Yes, the bridge is from 1929 but apparently it reuses earlier elements (embankments? parts of support structure?). At least that's what people in this thread are saying.

In general you can only patch up things up to a point. Especially if environment is changing around the structure.

The bow-string arches, central pier and north pier date from 1907. Beyond the north pier the 1850 viaduct (over-land section) was retained but later rebuilt as brick arches. Perhaps this is what the 1929 date refers to? The 1850 south abutment was retained and smartened up in 1907. This is the section that has failed.

 

[MarkyT]

The BBC report‘s video (no longer available) actually showed there is only an embankment on the south side, all the way up to the abutment.

Oops you are quite correct! I'd somehow switched to looking at the wrong Thames bridge (the one nearer Appleford) on Google Earth.

 

[Geogregor]

The bow-string arches, central pier and north pier date from 1907. Beyond the north pier the 1850 viaduct (over-land section) was retained but later rebuilt as brick arches. Perhaps this is what the 1929 date refers to? The 1850 south abutment was retained and smartened up in 1907. This is the section that has failed.

It is basically a mess. Which might be part of the problem, add-on, on top of an add-on, on top of an yet another add-on. Most of it 100 years old or more, designed in times when knowledge of geomorphology and hydrology was on completely different level. Then we have changes in precipitation and flow due to climate change (as well as other hydrological intervention in the region over the decades).

I know it will cost but at some point bridges have to be replaced. Which I find strangely rare in the UK, comparing with some other countries, which is weird when we consider age of our assets.

 

[Mark J]

The last day of rail traffic over Nuneham Viaduct was last Saturday, with the 22:38 to Paddington and 22:19 from Reading being the last services over it.

Trains were crawling along over the top of it last Saturday (at 5mph?), and only one at a time. There was a freight train on the opposite line waiting for the XC service I was on to cross the bridge.

This issue has been known for a while, with 20mph speed restrictions in place for quite a while. Why wasn't proper work done until it was on the verge of collapsing?

I also see the National Rail App hasn't yet been updated. It still shows rail services running to Oxford in both directions this coming bank holiday weekend.

 

[webweasel]

The ground is obviously pretty dodgy because the 1850 bridge (which was built using cast iron screw-piles) kept sinking! There are gravel pits nearby as well.

 

[Chingy]

The last day of rail traffic over Nuneham Viaduct was last Saturday, with the 22:38 to Paddington and 22:19 from Reading being the last services over it.

Trains were going over it Monday morning, until it got pulled mid morning.

Realtime Trains | Departures from Oxford between 0600 and 2000 on 03/04/2023

Train information at Oxford between 0600 and 2000 on 03/04/2023. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

 

[FGW_DID]

The last day of rail traffic over Nuneham Viaduct was last Saturday, with the 22:38 to Paddington and 22:19 from Reading being the last services over it.

There were trains running over it on the Monday morning before it was closed about 10:30.

 

[Mark J]

There were trains running over it on the Monday morning before it was closed about 10:30.

There were no trains over Nuneham Viaduct last Sunday (2nd April).

I was planning to go to Oxford by train, only to discover rail replacement buses from Didcot Parkway to Oxford.

Didn't realise train services had briefly restarted over the route on Monday morning.

 

[156444]

The last day of rail traffic over Nuneham Viaduct was last Saturday, with the 22:38 to Paddington and 22:19 from Reading being the last services over it.

Trains were crawling along over the top of it last Saturday (at 5mph?), and only one at a time. There was a freight train on the opposite line waiting for the XC service I was on to cross the bridge.

This issue has been known for a while, with 20mph speed restrictions in place for quite a while. Why wasn't proper work done until it was on the verge of collapsing?

I also see the National Rail App hasn't yet been updated. It still shows rail services running to Oxford in both directions this coming bank holiday weekend.

The bridge was open on Monday morning for a while. I believe the last train over it was this: https://www.realtimetrains.co.uk/service/gb-nr:K04500/2023-04-03/detailed which was 769943.

 

[Purple Train]

On Google Maps I make the reversing siding 140m from Stop block to dolly, you can knock 2m off for stopping distance at the buffers, and probably 5m off for standing clear of the signal, so 132m. 5x25 = 125m, so I'd only have to be out by 7m (easy enough using Google Maps) for the 5-Car unit to not fit. It's tight, but possible, but as ever there's usually a reason why Control doesn't 'just f***ing do it' without checking first.

I believe the siding was specifically extended so a 5-coach IET could fit.

Back on topic, how long has the bridge been deteriorating? I remember slowing to pass over it when travelling northbound back in October, but how long was it going on before that?

 

[FGW_DID]

The bridge was open on Monday morning for a while. I believe the last train over it was this: https://www.realtimetrains.co.uk/service/gb-nr:K04500/2023-04-03/detailed which was 769943.

Something else to blame on the 769s!

 

[Mcr Warrior]

There were trains running over it on the Monday morning before it was closed about 10:30.

So, what was the last service train to make it across? The 1016 XC service from Reading to Manchester Piccadilly?

 

[zwk500]

So, what was the last service train to make it across? The 1016 XC service from Reading to Manchester Piccadilly?

Nope, that doesn't appear to have made it https://www.realtimetrains.co.uk/service/gb-nr:C71733/2023-04-03/detailed

 

[Mark J]

Something else to blame on the 769s!

A least GWR did one good thing in getting rid of those awful rebranded Thameslink 319 cast offs.

 

[Jimini]

So, what was the last service train to make it across? The 1016 XC service from Reading to Manchester Piccadilly?

Nothing on RTT for that one after Didcot East, so guessing it didn't make it.

The bridge was open on Monday morning for a while. I believe the last train over it was this: https://www.realtimetrains.co.uk/service/gb-nr:K04500/2023-04-03/detailed which was 769943.

This looks like the last one.

Edit: you said service train, so maybe the 0725 from Manchester (passed the incident site at ~1030):

Realtime Trains | 1O08 0725 Manchester Piccadilly to Bournemouth | 03/04/2023

Real-time train running information for 1O08 0725 departure from Manchester Piccadilly to Bournemouth on 03/04/2023. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

Also looks like this service to Hereford was diverted via. Swindon / Cheltenham right as the closure kicked in (eventually terminated at Worcester):

Realtime Trains | 1W01 0950 London Paddington to Worcester Foregate Street | 03/04/2023

Real-time train running information for 1W01 0950 departure from London Paddington to Worcester Foregate Street on 03/04/2023. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

 

[Saj8]

The last train on the up was 2L27, the 10.05 OXF - DID stopper. The unit was held at Didcot for a while, unable to run its return 2L22 service to Oxford, before going empty to Reading Traincare Depot.

Edit: actually, looks like it was 1O08, as Jimini states above, which was a few minutes behind this one.

 

[12LDA28C]

Latest industry rumours suggest the line will be closed for at least 12 weeks, maybe more.

 

[Jimini]

The last train on the up was 2L27, the 10.05 OXF - DID stopper. The unit was held at Didcot for a while, unable to run its return 2L22 service to Oxford, before going empty to Reading Traincare Depot.

Think the XC service went through after that. Happy to be corrected though!

 

[stuving]

It's not VERY old. According to this page https://thames.me.uk/s01530.htm the current structure is the third bridge on the site, built in 1929. There are short brick-built viaduct sections on land at both sides of the river, the one at the south end being the longer one. From the photo up-thread, the curve suggests the problem is with the south bank support for the southerly steel span. I wonder if its foundation has been scoured out by recent floodwater?

That date of 1929 on thames.me.uk has got onto the wrong page - it relates to Appleford viaduct. The bit about "a single bow structure" clearly belongs there.

If you rely on the two pages of the Great Western Railway Magazine, quoted by Culham Ticket Office (Nuneham and Appleford), and on some news reports from 1931, you get this sequence:

The first steel bridges at Nuneham and Appleford date from 1856, were very similar, and each extended as a viaduct - to the north (Nuneham) or both ends (Appleford).

The bridge part at Nuneham was replaced in 1906/7 with the current two-span structure. The viaduct part was kept (but perhaps shortened a little). New piers were built mid-river and on the north side; I have no information on what was done to the southern abutment. It must have had new bearings, perhaps allowing for expansion; on the north pier the girders appear to just sit on blocks of concrete.

Appleford was all replaced in 1927/29, with a single-span bridge and brick arches. This bridge had "roller bearings". The new bridge is slightly to the east of the old one, so that two tracks could be kept open throughout the work.

The viaduct part at Nuneham was rebuilt in brick (finishing) in 1930, following the pattern used at Appleford.