Part of the viaduct at Nine Elms has collapsed.

[Paul180]

This has just popped up in my Twitter feed
https://twitter.com/EmilTschepp/status/1342506596698566656

It looks like part of the viaduct carrying the mainline railway in to London Waterloo has collapsed at Nine Elms, near the US Embassy.

Looking at the photos it looks like the parapet has collapsed, possibly been hit with an excavator.
It looks like it will take some cleaning up.

 

[Parham Wood]

Looks like at least one layer of bricks or more have come away down to the arch.

 

[edwin_m]

Something must have hit the parapet pretty hard, and the brickwork is probably also in poor condition to have pulled away like that. Those cables probably control some pretty important stuff as well.

 

[Signal Head]

Something must have hit the parapet pretty hard, and the brickwork is probably also in poor condition to have pulled away like that. Those cables probably control some pretty important stuff as well.

More photos

 

[MadMac]

That’s a couple of signal cases. That’s going to take a while.....

 

[Signal Head]

That’s a couple of signal cases. That’s going to take a while.....

Indeed. The test log somewhat understates the problem.

I understand someone was working in one when it happened and a colleague hung on to him so he didn't go with it.

 

[jopsuk]

location would seem to be here, yes? (google streetview link to Ponton Road)

 

[fkofilee]

Is it to do with this?



I only ask because location wise seems quite close?

 

[edwin_m]

Is it to do with this?

View attachment 87772

I only ask because location wise seems quite close?

A different incident? This one seems somewhat more severe than a signal being damaged, and according to the OP it's on the Waterloo lines not the ones leading to Victoria.

 

[Geogregor]

location would seem to be here, yes? (google streetview link to Ponton Road)

It looks like this location.

Also, looking at how things looked before the incident, I wonder if they didn't overload the edge of the viaduct with various strictures (likes signaling equipment boxes etc.) some of them protrude outside the envelope of the structure. I'm sure someone calculated everything but the old brick structures might be difficult to recalculate due to lack of drawings etc.

 

[Ploughman]

I was thinking that myself.
The weight of cable alone would seem to be a significant amount.
I think a fresh assessment of similar locations will be high on the list of jobs to do in the near future.

 

[swt_passenger]

There probably won’t be an entry for this on the NR current Disruptions page if it’s already under possession until 3rd Jan.

I agree the Southern problem mentioned earlier is almost certainly unrelated.

 

[randyrippley]

That brickwork looks quite rotten: the way that many of the bricks have dropped away as clean singles shows there is no strength in the mortar. Probably old washed out lime cement. The only solid-looking masonry is the arch infill brickwork which looks like it has proper mortar. I'd even hazard a guess that much of the load is now carried by the infill and not the original brickwork.
At some point these brick arches are going to have to come down

 

[MadMac]

Indeed. The test log somewhat understates the problem.

I understand someone was working in one when it happened and a colleague hung on to him so he didn't go with it.

Best understatement I've ever seen came from the Duty Engineer in the log at Emley Moor TV transmitter: "1265ft Mast - Fell down across Jagger Lane (corner of Common Lane) at 17:01:45. Police, ITA HQ, RO etc all notified.".

 

[Nicholas Lewis]

That brickwork looks quite rotten: the way that many of the bricks have dropped away as clean singles shows there is no strength in the mortar. Probably old washed out lime cement. The only solid-looking masonry is the arch infill brickwork which looks like it has proper mortar. I'd even hazard a guess that much of the load is now carried by the infill and not the original brickwork.
At some point these brick arches are going to have to come down

Looks like track renewals is happening given the train load of Falcon wagons in the picture. Always a risk while your excavating and dozing next to the parapet walls as they aren't designed to take the side loading exerted on the structure as the machines push through. Signalling probably only affected on Windsor side as the cases are run on both sides between waterloo and clapham jcn. Could have been far more significant in other areas where public road and spaces are directly below the viaducts.

 

[Tim M]

It looks like this location.

Also, looking at how things looked before the incident, I wonder if they didn't overload the edge of the viaduct with various strictures (likes signaling equipment boxes etc.) some of them protrude outside the envelope of the structure. I'm sure someone calculated everything but the old brick structures might be difficult to recalculate due to lack of drawings etc.

About 40 years ago I was part of the cable and location case survey team for Victoria Area Resignalling, and am sure the same applied on the Waterloo Area Resignalling. The team comprised from BR: Senior Signalling Engineer, Installation Supervisor with measuring wheel, (when the wheel came off the rail head we called out the Stewart’s Lane breakdown train ), Installation Assistant with marker paint, Civil Engineer’s Representative, Contractors Engineer (me), Contractors Installation Engineer, cable Route Contractors Engineer and the BR Lookout.

Note the civil engineers involvement. Each part of the route would be surveyed at least twice giving all involved time to assess installation requirements and restrictions.

 

[hwl]

Looks like track renewals is happening given the train load of Falcon wagons in the picture. Always a risk while your excavating and dozing next to the parapet walls as they aren't designed to take the side loading exerted on the structure as the machines push through. Signalling probably only affected on Windsor side as the cases are run on both sides between waterloo and clapham jcn. Could have been far more significant in other areas where public road and spaces are directly below the viaducts.

Wessex route - Network Rail

Wessex is one of the busiest routes on the rail network, taking in all or part of the counties of Surrey, Berkshire, Hampshire, Dorset and Somerset

www.networkrail.co.uk

Service changes between London Waterloo and Clapham Junction, Sunday 27 December 2020 to Sunday 3 January 2021​

There will be a significantly reduced service over the Christmas and New Year period while we carry out major work between Clapham Junction and London Waterloo.

During this time, Vauxhall and Queenstown Road stations will be closed, as will platforms 12 to 20 at London Waterloo.

Trains from the direction of Reading, Windsor & Eton Riverside and Hounslow will terminate at Clapham Junction, with passengers needing to change for onward travel to London Waterloo. For the safety of our passengers, London Waterloo and Clapham Junction stations are both likely to use queuing systems.

This major programme of work will provide passengers with more punctual and reliable train journeys to and from London Waterloo, Britain’s busiest railway station.

What we’re doing​

Between Friday 25 December 2020 and Monday 4 January 2021, engineers will carry out a major programme of work at Nine Elms Junction, a vital part of the South Western Railway (SWR) network, between Clapham Junction and Vauxhall.

The majority of this work will involve renewing both sections of track and switches and crossings. Engineers will also carry out resignalling work, vegetation clearance and track and bridge inspections.

All of this work will close the ‘Windsor lines’ that take trains from the direction of Reading, Windsor & Eton Riverside and Hounslow, through Clapham Junction, and on to London Waterloo.

At London Waterloo we will carry out maintenance on the tracks at a number of platforms. To ensure engineers can safely access those tracks and complete their work, platforms 12 to 20 at the station will be closed.

All of these improvements are being carried out over the Christmas and New Year period when fewer passengers are travelling, minimising the impact from reduced services.

Travel information​

Passenger services will be affected between Sunday 27 December and Sunday 3 January. Services will run as normal from Monday 4 January.

Passengers are advised to note the following travel information:

• On Thursday 24 December, SWR services will end earlier than normal
• Between Friday 25 December and Sunday 3 January, Vauxhall and Queenstown Road stations will be closed
• Between Sunday 27 December and Sunday 3 January, passengers travelling from the direction of Reading, Windsor & Eton Riverside and Hounslow to London Waterloo will need to change at Clapham Junction. Due to these trains terminating early, there will be a reduced number of services between Clapham Junction and London Waterloo. Platforms 12 to 20 at London Waterloo will be closed. Both London Waterloo and Clapham Junction may be busier than usual, with queuing systems in place.
• Passengers are advised to check with SWR or National Rail Enquiries before they travel on Thursday 31 December.

 

[Peter Mugridge]

That brickwork looks quite rotten: the way that many of the bricks have dropped away as clean singles shows there is no strength in the mortar. Probably old washed out lime cement. The only solid-looking masonry is the arch infill brickwork which looks like it has proper mortar. I'd even hazard a guess that much of the load is now carried by the infill and not the original brickwork.
At some point these brick arches are going to have to come down

For years this area has had a lot of buddleia growth; I wonder if that played a factor in weakening the structure?

 

[PG]

That’s a couple of signal cases. That’s going to take a while.....

Indeed. The test log somewhat understates the problem.

I understand someone was working in one when it happened and a colleague hung on to him so he didn't go with it.

Hopefully neither him or his colleague have suffered any serious injuries. Probably owes his colleague more than a pint!

Should imagine this will have been reported to RAIB - do we reckon it's a safety digest or full report?

 

[Aictos]

Is it to do with this?

View attachment 87772

I only ask because location wise seems quite close?

Believe that was a power failure as National Grid engineers were called out to restore power as per TL and SN Twitter feeds.

They've just reopened the lines affected but services still subject to delay, alteration and cancellation.

 

[Signal Head]

Hopefully neither him or his colleague have suffered any serious injuries. Probably owes his colleague more than a pint!

Should imagine this will have been reported to RAIB - do we reckon it's a safety digest or full report?

I would think a full report, given that the reasons for the collapse - and for the apparent underlying (and clearly undetected) structural weakness may be complex.

As randyrippley has noted above, the exterior wall appears to have disintegrated, rather than fallen off in large pieces still bonded together. Why wasn't the state of the mortar bonding picked up on inspection? It surely won't have deteriorated 'overnight'. Are there implications for the rest of the structure, and other similar ones?

If this had happened under traffic, what is the risk that a train could have 'exited the structure' (a somewhat euphemistic phrase I remember being used by a BR CE talking about failure modes of Ribblehead viaduct) ?

I don't see how all that could be catered for in a safety digest, which I suspect are more suited to incidents where the cause is more obvious, and involves someone ignoring, or ignorant of, the rules or best practice.

 

[edwin_m]

Safety digests also tend to be for incidents that are similar to one that has been investigated in full recently, so they essentially say that and repeat the lessons/recommendations. There may also be a tendency to produce one if the incident is more of a one-off than something from which significant lessons could be learned.

I doubt this one qualifies on either count, unless perhaps it was caused by something straightforward such as a heavy impact from a piece of plant. There have been incidents where the parapet and even the sidewall of a structure have come down due to road or rail vehicle impact or internal water damage but if this was simply some fairly routine trackwork in close proximity then it would appear to be something new. Not being a structural engineer, I won't comment on whether this could have precipitated the collapse of the arches under the railway, but as someone mentioned there are many viaducts where people below might be at risk from a similar event.

 

[theageofthetra]

I wonder if this very lucky escape could lead to a 'Hatfield' type inspection of similar structures? The state of some of brick railway structures in South London is appalling, trees, bushes etc growing through them, water flowing through them etc.

 

[randyrippley]

For years this area has had a lot of buddleia growth; I wonder if that played a factor in weakening the structure?

It won't have helped as the roots would prise the joints apart and also make it easier for water to penetrate, but the simple fact is that from the photos the brickwork looks rotten with the old mortar washed out. The structural strength will have gone and no amount of repointing is going to fix that. It's mainly just a function of wetness and age - but it has to ring warning bells for much of the national infrastructure. Proper Portland cement began to come into use around 1860-1870, though there were earlier versions. Anyone know when this viaduct dates from?

 

[nlogax]

1848 I believe.

 

[randyrippley]

1848 I believe.

Just found the viaduct has its own wiki page at https://en.wikipedia.org/wiki/Nine_Elms_to_Waterloo_Viaduct

The opening of the viaduct and line was planned for 30 June 1848, but the Board of Trade Inspector did not approve some of the large-span bridges at the eastern end, however his superior was satisfied by later load tests, and the line opened on 11 July 1848. Further widening of the viaduct took place between 1877 and 1868 and again from 1898, when an eight-track railway all the way through from Waterloo to Clapham Junction was completed (taking until 1910 to be fully completed). The opening of the viaduct and line was planned for 30 June 1848, but the Board of Trade Inspector did not approve some of the large-span bridges at the eastern end, however his superior was satisfied by later load tests, and the line opened on 11 July 1848. Further widening of the viaduct took place between 1877 and 1868 and again from 1898, when an eight-track railway all the way through from Waterloo to Clapham Junction was completed (taking until 1910 to be fully completed).

 

[nlogax]

Just found the viaduct has its own wiki page at https://en.wikipedia.org/wiki/Nine_Elms_to_Waterloo_Viaduct

Interesting..do we know if the failed portion is part of the original structure or the widened side? (Or was the structure widened outwards on both sides?)

 

[GB]

So, we have had suggestions it was hit by a dozer (or similar), it was undermined by engineering works, potentially overloaded with S&T stuff and now due to the state of the viaduct itself....which is it or should we wait for investigations to conclude?

 

[randyrippley]

Interesting..do we know if the failed portion is part of the original structure or the widened side? (Or was the structure widened outwards on both sides?)

that's going to be interesting to see.........172 year old masonry or 110 year old masonry????

So, we have had suggestions it was hit by a dozer (or similar), it was undermined by engineering works, potentially overloaded with S&T stuff and now due to the state of the viaduct itself....which is it or should we wait for investigations to conclude?

We don't know the cause, but the incident has shown the brickwork - at least in part - to be rotten.
There's a bigger overall question regarding the inspection and safety regime than just this one failure.

 

[Bletchleyite]

I wonder if this very lucky escape could lead to a 'Hatfield' type inspection of similar structures? The state of some of brick railway structures in South London is appalling, trees, bushes etc growing through them, water flowing through them etc.

Must admit one that sprung to mind recently was when walking over the road footbridge just outside Vauxhall, the wall adjacent to that looks just ready to fall over.