Issues North of Newcastle - Plessey Viaduct - 09/10 (onwards)

[Bletchleyite]

What I find more troubling is the description of the collapsed wall as a parapet and that the viaduct’s structural integrity is intact.

Again they're speaking to laypeople. By "the viaduct's structural integrity is intact" they mean "don't worry about travelling by train over the other line, it's not about to fall down". They're not getting into the engineering technicalities of exactly what has fallen off (which does appear to include a bit of the upper brickwork of one arch. but nothing under it).

They are in a similar dilemma to airlines, who sometimes speak a little euphemistically in order to avoid terrifying nervous flyers when something has gone a bit wrong.

 

[800001]

Disruption now expected to end of day November 3rd according to LNER.

 

[swt_passenger]

If you read all of it they explain that the original issue was it moving but that it doing so knocked a load off as a secondary issue. Or that's how I read it, anyway.

As in this:
...reads to me that the movement knocked that off.

It seems it’s no longer possible to read a sequence of posts on Twitter. So we’ll have to rely on members for that sort of detail. Be good if NR actually used accessible channels to disseminate news…

 

[Bletchleyite]

It seems it’s no longer possible to read a sequence of posts on Twitter.

Worked for me, click on the top one and the sequence appears below.

Or if that doesn't work, reply to it with "@threadreaderapp unroll" and the Twitter thread reader bot will stick it on a web page for you.

 

[heathrowrail]

Yes there is a photo doing the rounds where the person has said ‘it will take 12-18 months to plan and replace’.

Crazy yet they can repair the Nuneham Viaduct in Oxford in 3 months and the Dawlish sea wall in 3 months too.

 

[skyhigh]

Crazy yet they can repair the Nuneham Viaduct in Oxford in 3 months and the Dawlish sea wall in 3 months too.

Until something official is said I'd take the date given in a screenshot of a message from someone unknown with a large pinch of salt to be honest.

 

[yoyothehobo]

Crazy yet they can repair the Nuneham Viaduct in Oxford in 3 months and the Dawlish sea wall in 3 months too.

Depends also on whether they keep the route open or not, its a hell of a lot easier to work on a closed railway than an open one.

 

[DarloRich]

It seems it’s no longer possible to read a sequence of posts on Twitter. So we’ll have to rely on members for that sort of detail. Be good if NR actually used accessible channels to disseminate news…

it works perfectly well. It is a thread of 9 posts all scrolling perfectly happily on both my phone and laptop but seconds ago. Twitter is an accessible channel for many normal people. The issue is you don't want to use it which is absolutely your choice. I bet the same info is available on other social media channels. However, don't complain if an channel/forum that NR and other business chose to use to use to quickly and widely communicate information is not your preferred option.

it is a forum that allows for quick and easy dissemination of information to the widest possible readership.

PS yes, Elon Musk is an end.

 

[fkofilee]

(1/9) - We’re sorry for disruption to some journeys on the northern end of the East Coast Main Line. It’s caused by structural issues we’ve found on the viaduct at Plessey between Morpeth and Cramlington stations.

Twitter thread below. Link at end of thread.








https://twitter.com/networkrail/status/1711330607106531536 - Incase people cant login to X or dont have an account.

 

[yorkie]

Forum rules do require a text quote to be provided (in addition to a link & comment); if anyone has any queries or concerns about this, please contact us directly.

If anyone would like to discuss the features, merits, owner or any other aspect of Twitter/X further, please create a new thread (if there isn't one already!) in the General Discussion section.

Thanks

 

[liamf656]

For those that choose to either not open a link to Twitter or read back a page on the forum (it’s post #82) here it is again:

We’re sorry for disruption to some journeys on the northern end of the East Coast Main Line.

It’s caused by structural issues we’ve found on the viaduct at Plessey between Morpeth and Cramlington stations.

– Please check your journeys before you travel with your train operator or via @nationalrailenq: https://nationalrail.co.uk

– What’s happened between Morpeth and Cramlington stations?

During planned track work, we found that the viaduct’s parapet – the safety barrier at the edge of the bridge – had moved.

– So why has this disrupted services? The site location, viaduct design and heavy machinery involved meant it was impossible to quickly move the parapet back to its original position. Our priority is to keep you safe, so one of the lines on the viaduct is currently closed.

– And what’s happening now?
Structural engineers and other specialists are working on different options. These include rebuilding or realigning the structure. We’re also looking into the time and access each option will take.

– We need to work through each option before we can open the line going north to traffic again.

We’re making a detailed plan and will do everything we can to minimise the impact on you and freight. We’ll continually review the plan to make sure it works well.

– The viaduct’s structural integrity is intact. The damaged is contained to part of the parapet, which we strengthened in 2014.

The issue is with 20 metres of the wall leaning away from the north end of the viaduct, where the railway line goes north.

– The movement has displaced about 30t of masonry and concrete on the bridge, which is 177 years and is Grade II listed.

– We are sincerely sorry for the inconvenience this will cause you and our freight partners until we’ve completed the repairs.

We’ll give you more information as soon as we can.

 

[Dr Hoo]

Thank you @liamf656.

For the avoidance of doubt, some of us who do not PhDs in Software Engineering or an X account but still have modern phones and computers are nevertheless unable to interact with what appears to be a ‘frozen’ screen shot at Post #82.

 

[josh-j]

it works perfectly well. It is a thread of 9 posts all scrolling perfectly happily on both my phone and laptop but seconds ago. Twitter is an accessible channel for many normal people. The issue is you don't want to use it which is absolutely your choice. I bet the same info is available on other social media channels. However, don't complain if an channel/forum that NR and other business chose to use to use to quickly and widely communicate information is not your preferred option.

it is a forum that allows for quick and easy dissemination of information to the widest possible readership.

PS yes, Elon Musk is an end.

They can post there but they shouldn't only post there (or other private platforms).

Most people don't have Twitter accounts and nobody should be forced to have one (and let Musk into their lives) just to get updates from a publicly owned body about public transport.

 

[dk1]

Was 10mph ESR over the bridge, now increased to 50mph.

Good to hear, thanks.

 

[Amlag]

I believe the engineering work just uncovered it as there was a planned rerail that evening so the excavators uncovered the extent of the damage while carrying out the rerail.

Was the sidewall accidentally ‘nudged’ / touched by an excavator ?

 

[modernrail]

As a layman I have to say that I am really surprised that anything is running over there. Especially in an increasingly risk adverse world.

I assume that whatever the shortcomings of any previous inspection regime, a very detailed inspection has now taken place that really convincingly confirms that trains moving over here is not going to cause further damage or worse. Is that not quite a big call to make? Is there a risk it could turn out to the the wrong call or can other engineers on here see that no, that is likely a very solid call?

 

[800001]

As a layman I have to say that I am really surprised that anything is running over there. Especially in an increasingly risk adverse world.

I assume that whatever the shortcomings of any previous inspection regime, a very detailed inspection has now taken place that really convincingly confirms that trains moving over here is not going to cause further damage or worse. Is that not quite a big call to make? Is there a risk it could turn out to the the wrong call or can other engineers on here see that no, that is likely a very solid call?

A full examination has taken place over Saturday and Sunday by various agencies and they authorised the movement of trains over the bridge.
The actual viaduct and the track bed is solid and safe.

 

[Trestrol]

It's just as well that Morpeth signal box is still open as it's on its door step to arrange SIMBIDS. Soon Morpeth, Alnmouth and Tweedmouth will all be on Tyneside IECC.

 

[Bald Rick]

Crazy yet they can repair the Nuneham Viaduct in Oxford in 3 months and the Dawlish sea wall in 3 months too.

Crazy how not every structural failure is the same…

 

[DelW]

Crazy yet they can repair the Nuneham Viaduct in Oxford in 3 months and the Dawlish sea wall in 3 months too.

The "12 to 18 months" quote seems to have come from someone with unknown technical knowledge, and in the immediate aftermath of the failure. An accurate programme for the repair needs as a minimum: a defined scope of works, an outline design of the necessary temporary works, and a knowledge of what levels of design and construction resources are available. Those are likely to be being worked on urgently, after which a meaningful timescale will be known. I suspect it will be rather less than 12 to 18 months, but we will see.

 

[Deepgreen]

The roots could have caused the structure to weaken and led to the collapse. It's a reasonable size.

It's a small tree gowing horizontally from one section. That won't have caused the whole length to collapse like that. It looks as if something has run along the parapet forcing it sideways, almost as if a long section of lifted rail has crashed against the stonework. I'm not saying that is what happened, it just looks something like that.

 

[najaB]

I suspect it will be rather less than 12 to 18 months, but we will see.

That's the kind of time that would be needed for a complete rebuild or replacement. Hopefully we're nowhere near that kind of intervention being needed.

 

[edwin_m]

Interesting it says they found parapet wall had moved and they didn't have machinery to move it back. If it had they shouldn't have ripped out all the track out. Still feels like the track renewal has caused the failure even if the wall was weakened already. Also did they then to decide to demolish wall or did it collaspe.

From the photos in #33 it is clear that there is a substantial depth of ballast below where the track was. This has fallen or been removed to leave a slope of about 45 degrees, which is probably judged to be an angle at which large quantities are not likely to slip and fall (it's similar to the angle of a normal ballast shoulder - and note there is always going to be a risk of individual stones falling so I sincerely hope the area underneath has been barriered off). It's likely some of the sleeper ends would have projected over the top of this slope, so taking the track out made it easier to stabilise and also removed some weight that might have increased pressure on the structure. I assume this track removal was done very carefully, using plant running on the other track, and after a structural engineer had given the OK. And they would also have to be satisfied that the arches themselves were sound before giving the OK to put any weight or any people on that side.

Not a civil engineer but I'd guess they either have to re-build the side wall as was (but better!) and backfill it, or build some sort of concrete deck to support the missing track.

 

[Bayum]

this was posted in the local Morpeth Facebook group. Not looking good…

Shows why they have issues

Flighting means you run a bunch of services in one direction one after the other, then swap direction and run a bunch the other way rather than continually alternating direction.

Is it going to withstand that? Can’t see pax being happy taken over that.

 

[hexagon789]

Is it going to withstand that? Can’t see pax being happy taken over that.

They've been doing that all day today...

With most trains picking up only a 5 min delay and broadly managing to recover it.

 

[Nicholas Lewis]

This is a screenshot from a Don Coffey video uploaded Dec22 from a TPE 802 so likely pretty recent



The two rails in the pictures further up the thread are probably the gathering rails removed before taking out the track. Also can be seen clearly how the parapet wall has been modified as referred to in NRs tweet. Looks like cast concrete lintels were used when the parapet wall was refurbished of course exactly how that interfaces to the old structure isn't clear but this is another picture from underneath

which shows how the position of safety route overhangs the viaduct side. Courtsey of https://www.bridgesonthetyne.co.uk/plesvia.html

There looks reasonable space off the sleeper ends compared to brick viaducts ive worked on in London area where sleeper ends are often up against the troughing route which is hard up against the wall so easy with track renewals machinery to impart a sideways load onto walls. That said I remain of the view that the track renewal activity has been a contributory factor here although the underlying problem may lay with the interface between old structure and the replacement parapet wall.

 

[Class 170101]

It's just as well that Morpeth signal box is still open as it's on its door step to arrange SIMBIDS. Soon Morpeth, Alnmouth and Tweedmouth will all be on Tyneside IECC.

Won't make any difference whether it was controlled by Morpeth Signal Box or Tyneside IECC. If anything it would be easier if it was on just one controlling signal box / workstation as then only one signaller would be in control rather than two.

 

[najaB]

Is it going to withstand that? Can’t see pax being happy taken over that.

As was noted earlier in the thread, the loads imparted by a train passing over are pretty much straight down vertical, rather than sideways. So the ballast isn't likely to shift that much more than it already has.

That said, I'm pretty sure that there will be monitoring in place (be it electronic or the Mk 1 eyeball) to ensure that everything remains where it currently is.

 

[glasgowniteowl]

Not really a surprise but LNER staff being briefed today that the repair is going to take multiple weeks

 

[tedlit]

This matches what journeycheck says now. Specifically, for TPE:

Due to urgent repairs to a bridge between Newcastle and Edinburgh fewer trains are able to run on all lines.
Impact
Train services running through these stations will be cancelled or delayed. Disruption is expected until the end of the day on 03/11/23.