Nuneham Viaduct shut - Didcot- Oxford

[Annetts key]

I would expect a speed restriction to be used until the engineers are happy that the embankment is stable and the new ballast formation is stable.

 

[mr_moo]

Agreed. Normal linespeed there is 90mph. With all the new fill and the new track there will definately be some expected settleemnt under traffic and thus there is highly likely to be a 50mph speed restriction (the standard used after track renewals) over it for several weeks after opening, possibly lower due to all the embankment works as well. There will also almost certainly be lots of monitoring on the tracks so any settlement is readily identified and rectified.

 

[Nicholas43]

Hope this is not speculation, and 4E91 (for example) is likely to run as planned on 9 June!

 

[GRALISTAIR]

Great progress and puts the doomsters firmly in the long grass that the date would be achieved.

Nothing like a crisis to bring out the best in our industry.

Yes they are the best.

 

[Freightmaster]

Hope this is not speculation, and 4E91 (for example) is likely to run as planned on 9 June!

Still plenty of 'liners booked to run via London on that date:

Realtime Trains | Departures from Southampton M.C.T. all day on 09/06/2023

Train information at Southampton M.C.T. all day on 09/06/2023. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

MARK

 

[GRALISTAIR]

Surely the Network Rail test train will cross it first?

 

[zwk500]

Surely the Network Rail test train will cross it first?

I'd have though a Tamper would be the first across.

 

[GRALISTAIR]

I'd have though a Tamper would be the first across.

My mistake. You of course, are absolutely correct.

 

[zwk500]

My mistake. You of course, are absolutely correct.

Well, a 66 on the ballast train might yet prove me wrong. But a test train won't actually need to check the bridge for a while as it being newly laid means it should all be in tolerance. However it may pay a visit quite quickly as Didcot-Oxford may well need a check soon enough.

 

[Annetts key]

I imagine a “360” digger/excavator on track machine or a welders trolley may be the first rail “vehicle” across…

 

[CharlieSpotted]

As a layperson, I'm blown away by the engineering effort that's gone into this, the speed of the work for something that seems like an incredibly substantial and complicated project, and the standard of communication that NR have in providing updates and helping people to understand the problem and the solution being worked on.

Proves that "it" really can be done - "it" being engineering on a grand scale in response to an urgent need - if the situation demands it.

 

[zwk500]

Proves that "it" really can be done - "it" being engineering on a grand scale in response to an urgent need - if the situation demands it.

Yes it's incredibly impressive. I'd be interested to know the reaction when Peter Hendy gets the bill.

 

[mr_moo]

Yes it's incredibly impressive. I'd be interested to know the reaction when Peter Hendy gets the bill.

And there's the crux of it! The familiar triangle of delivery - Low Cost / Short time / High quality. Pick two for your project. Clearly cost is the one that was sacrificed here.
There's also the access etc of course. As an emergency the stuff just gets done as there's huge pressure and urgency, but as a planned works this would take ages to agree and get consents for etc etc.

 

[Nicholas43]

Won't Network Rail be having to pay operators huge sums for paths they contracted to provide, but currently cannot ? And therefore strongly driven to provide paths again from the target date of 10 June, at almost any cost ? What worries me, is the diversion to Nuneham of a substantial part of Network Rail's limited budget, at the expense of lots of other no doubt highly desirable schemes.

 

[quantinghome]

Great progress and puts the doomsters firmly in the long grass that the date would be achieved.

Nothing like a crisis to bring out the best in our industry.

Yes, it is great. But it reminds me of something I heard years ago from an experienced rail engineer, that the rail industry really likes responding to a crisis but is not so good at the 'boring' day to day stuff. Amid the great engineering we're seeing, let's not forget that this is ultimately responding to a long term failure. I will be very interested to read the report on the technical and managerial aspects of the failure.

 

[Bald Rick]

Won't Network Rail be having to pay operators huge sums for paths they contracted to provide, but currently cannot ? And therefore strongly driven to provide paths again from the target date of 10 June, at almost any cost ? What worries me, is the diversion to Nuneham of a substantial part of Network Rail's limited budget, at the expense of lots of other no doubt highly desirable schemes.

The ‘sums‘ won’t be that huge. not trivial, but not huge. This isn’t the WCML or Brighton Main Line.

And this is not a substantial part of NRs budget. It’s not even a substantial part of Wales & Western’s Renewals budget.

So no need to worry.

== Doublepost prevention - post automatically merged: 31 May 2023 ==

And there's the crux of it! The familiar triangle of delivery - Low Cost / Short time / High quality. Pick two for your project. Clearly cost is the one that was sacrificed here.
There's also the access etc of course. As an emergency the stuff just gets done as there's huge pressure and urgency, but as a planned works this would take ages to agree and get consents for etc etc.

This works both ways. I was party to a study in Western (many years ago, but its unlikely that the results are different) which demonstrated that emergency Civils works were typically 10% cheaper than the same work that was planned in normal timescales.

Essentially the time saving in doing the work in a rush - emergency powers of access, rushing through consents, compressing timescales in delivery (essentially through closing a line completely and doing the work in one go rather than doing the work in numerous stages spread over multiple weekends) more than offset the cost of calling in resource at short notice round the clock, and any costs of over engineering to get it done quickly.

This was only delivery costs of course, and did not take into account the costs of compensation to operators.

 

[Mcr Warrior]

And there's the crux of it! The familiar triangle of delivery - Low Cost / Short time / High quality. Pick two for your project. Clearly cost is the one that was sacrificed here.
There's also the access etc of course. As an emergency the stuff just gets done as there's huge pressure and urgency, but as a planned works this would take ages to agree and get consents for etc etc.

Would the job have been able to have been done (so relatively quickly) had the River Thames that flows underneath been flooding / in spate? Possibly not?

 

[jhy44]

I have optimistically booked to travel from Worcestershire Parkway to Paddington on Saturday 10th June and very excited to avoid the now-too-familiar detour via Birmingham or Swindon.

Very much hoping I haven't tempted fate and this does open on time as expected!

 

[reddragon]

And there's the crux of it! The familiar triangle of delivery - Low Cost / Short time / High quality. Pick two for your project. Clearly cost is the one that was sacrificed here.
There's also the access etc of course. As an emergency the stuff just gets done as there's huge pressure and urgency, but as a planned works this would take ages to agree and get consents for etc etc.

The reality is, the extra cost of unplanned works is counteracted by the huge savings of not doing the endless GRIP process, consultation etc so overall a massive cost saving.

Against that, unplanned track closure costs dwarf those planned 12+ weeks out with full consultation.

 

[The Planner]

The reality is, the extra cost of unplanned works is counteracted by the huge savings of not doing the endless GRIP process, consultation etc so overall a massive cost saving.

Against that, unplanned track closure costs dwarf those planned 12+ weeks out with full consultation.

Unless it was pre CPPP (confirmed period possession plan) at 26 weeks you are paying the full whack to operators.

 

[Bald Rick]

Against that, unplanned track closure costs dwarf those planned 12+ weeks out with full consultation.

in some places. But on much of the network an unplanned closure costs little.

 

[reddragon]

in some places. But on much of the network an unplanned closure costs little.

Yes, I find some possession take years to book, sometimes over 5 years costing big bucks! At the other end short notice access / possessions are cheap & done as a temporary block for just the cost of supervision.

 

[Nicholas43]

2 June: embankment rebuilt. Things on top of the new abutment in place.

 

[fishwomp]

Realtime trains is now showing freight to be back on 9th June, and passenger on 10th June. Great news!

Was hoping there might be a celebratory working of some steam from Didcot but alas not.

 

[zwk500]

Realtime trains is now showing freight to be back on 9th June, and passenger on 10th June. Great news!

Fantastic effort by the team to get that done.

Was hoping there might be a celebratory working of some steam from Didcot but alas not.

Well, sending a very heavy engine over it would be one way to test the formation. Is there anything mainline registered at Didcot? If there were to be a celebratory steam special I'd have thought Tyseley the more likely origin, but then again given how much passengers have been stuffed about by this blockage the best way you could celebrate reopening the bridge would have been to run a full timetable, not immediately send a Steam through to get in everybody's way.

 

[crablab]

Was hoping there might be a celebratory working of some steam from Didcot but alas not.

I was hoping that instead of planning "celebratory specials" the full timetable can be reinstated, so I don't have to take a 2 hour bus through Wallingford to get to Oxford.

 

[GrimJosef]

This picture was taken at around 16:00 on Jun 3rd. It doesn't show anything that can't be seen in Nicholas43's one a few posts further up, from the day before. There were still two machines on the top of the embankment. I watched them transferring material into a Volvo A30G which was taking it away. I followed the same walking route as a few weeks ago, but in the opposite direction this time, so I left the river bank via the Motocross track and headed for Clifton Hampden via the northern perimeter of the Culham Lab site. I'd planned to use the level crossing, as previously, but this has been fenced shut now (I was told by order of the County Council) so I crossed the line at the bridge 300m south instead. I came across a few contract staff who were professionally attentive, but just as considerate as last time.

 

[Nicholas43]

Photo around 4 pm on Sunday 4 June. Much activity at end of renewed embankment. Span appears to be resting on tray on plate on grey Thing on top of new abutment. One of each group of hydraulic jacks appears also to be in contact with the underside of the span.

 

[David Goddard]

In Birmingham for the weekend, so in theory the line is open again from Sunday, but booked to return via Cheltenham "just in case"
Also means bagging an HST ride so worth the detour!

 

[swt_passenger]

Photo around 4 pm on Sunday 4 June. Much activity at end of renewed embankment. Span appears to be resting on tray on plate on grey Thing on top of new abutment. One of each group of hydraulic jacks appears also to be in contact with the underside of the span.

Thanks for the regular updates.


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

Updated 1200 5 June

Network Rail reporting on Twitter that:

Our teams successfully lowered Nuneham viaduct onto the new abutment this weekend!
The embankment has now been built back up & we'll begin the reinstatement of the ballast & tracks in preparation for the line reopening on 10 June

https://twitter.com/networkrailwest/status/1665658184772599808

First photo of four shows the bridge girders being reinstated where they had been removed for piling rig access.

Second photo shows additional steelwork added over the hexagonal embankment piles, presumably to carry the ballast at the interface?