Concrete vs wooden sleepers

[Bletchleyite]

In the UK, it seems that concrete (or steel) are synonymous with welded rail, yet in most of the rest of Europe sleepers are still largely wood.

Why is this?

 

[Ploughman]

Weight for Concrete and Design for Steel.
Wood has very little resistance to Lateral movement and being lighter than concrete is also liable to vertical movement.

 

[hexagon789]

In the UK, it seems that concrete (or steel) are synonymous with welded rail, yet in most of the rest of Europe sleepers are still largely wood.

Why is this?

No idea, the French invented them I believe. I've never noticed greater use of wooden sleepers on the continent, and certainly as per Britain, France and Germany use only concrete on higher speed lines.

Wood doesn't last as long, is more expensive and not as strong; steel.is used on some lighter traffic/slower lines in the UK for weight/cost but seems to have fallen out of favour - the Settle-Carlisle was changed from steel to concrete because of issues with the steel sleepers.

I could understand wooden ones predominating on lighter uses rural lines in some of Europe, as per here but I wouldn't expect it on faster, heavier tracked lines.

 

[Mcr Warrior]

Are recycled plastic sleepers used all that much?

 

[hexagon789]

Are recycled plastic sleepers used all that much?

Don't know if there are any British installations, but New Zealand uses them

 

[Ploughman]

Ffestiniog I think.

 

[Mcr Warrior]

Ffestiniog I think.

Reckon you're right. Anywhere else in the UK?

Ffestiniog Railway use milk bottles for new rail sleepers

The Ffestiniog Railway has announced that it is replacing the wooden sleepers with brand new plastic ones.

www.railadvent.co.uk

Extract of story...

The Ffestiniog Railway has announced that it is replacing the wooden sleepers with brand new plastic ones.

Recycled mile bottles make up most of the plastic used in the new sleepers, which look very similar to the wooden ones, the differences only become apparent when you are close to them.

 

[D6130]

Concrete sleepers have been used exclusively in Italy for all track renewals for many years now, even on low speed and branch lines, likewise continuously-welded rail (with the exception of a few very sharply curved sections, as in the UK).

 

[Oxfordblues]

Yes indeed. When we were remodelling Porthmadog Harbour I lifted an original wooden sleeper only for it to fall to pieces in my hands. The new plastic ones should last at least 100 years.

 

[Bald Rick]

In the UK, it seems that concrete (or steel) are synonymous with welded rail, yet in most of the rest of Europe sleepers are still largely wood.

Why is this?

I’m surprised at this question - concrete is pretty universal for renewals on most European railways and have been for a while. There may be more timber out there because it hasn’t been renewed...

the Settle-Carlisle was changed from steel to concrete because of issues with the steel sleepers.

Steel sleepers are (were) laid in areas where there was low traffic, not high speeds, and what was underneath the sleepers was good enough to last for another 15 years+. The Settle and Carlisle had next to no renewals for about 20 years from the early 80s, and the track itself (sleepers and rail) was falling apart in places. The ballast was ok - ok enough to not need replacing. (Replacing the ballast under the sleepers is about half the cost of a normal track renewal). Relaying with steel sleepers was (still is) a cheap way of getting the track back into good condition, and a fair bit was done at various places on the S&C in the very late 90s / early 2000s.

Then lots of heavy coal imports started using the line, and the ballast deteriorated very, very quickly. Cue a need to replace the ballast, which meant lifting a lot of track - including some of the new steel sleepers - and putting it back on concrete.

 

[pdeaves]

Don't know if there are any British installations, but New Zealand uses them

A few years ago (maybe as much as 10, I can't remember) there was a Network Rail press release about using recycled plastic sleepers. I contacted them for some further information (where are they being installed?) but never had a reply. The presence of a press release suggests they exist somewhere on the main line.

 

[1955LR]

I seem to remember I read somewhere that wooden sleepers are used over some bridges as they act as damper to some dynamic loads into the bridge structure. Does anyone know if this is true?

 

[Class 170101]

Liverpool Street I believe has wooden sleepers because it was easier to install in the space and possession time available even though it has a shorter lifespan than concrete.

 

[D6130]

I seem to remember I read somewhere that wooden sleepers are used over some bridges as they act as damper to some dynamic loads into the bridge structure. Does anyone know if this is true?

Yes, this is true and small groups of wooden sleepers - usually about four at a time - are often used between station platforms, where they can be shortened to accommodate drainage catchpits between the lines. Obviously it's not possible to saw a few inches off the end of a concrete sleeper.

 

[chappers]

I’m sure I read an article in the PWI (Permanent Way Institute for those who don’t know) magazine that Newark flat crossing was relaid in plastic bearers. They had to have them spray painted brown, as otherwise they’d have been white when installed!

Yes, this is true and small groups of wooden sleepers - usually about four at a time - are often used between station platforms, where they can be shortened to accommodate drainage catchpits between the lines. Obviously it's not possible to saw a few inches off the end of a concrete sleeper.

It is actually possible to cut down a concrete sleeper. I think the saw was called a dura-blade; NR weren’t overly keen on it as the newly exposed end should be sealed, and there was a risk that exposing the reinforcement would lead it corrode quickly.

otherwise, it was generally NR’s preference for “short-ended” concrete sleepers to be installed around catchpits (these were sleepers where a few inches had been chopped off at the factory), although in some scenarios like at platform ends or where there were protruding structures at the platform footings woods were the only option

 

[alangla]

Steel sleepers are (were) laid in areas where there was low traffic, not high speeds,

IIRC, Airdrie to Bathgate was built using (machine laid) steel sleepers. That’s 85mph and in normal times, 4TPH, albeit 6 car EMUs & not freight. Whether they’d be used on a similar installation today is a different question.

 

[Bald Rick]

IIRC, Airdrie to Bathgate was built using (machine laid) steel sleepers. That’s 85mph and in normal times, 4TPH, albeit 6 car EMUs & not freight. Whether they’d be used on a similar installation today is a different question.

Typically the limits are max speed 90 or 100mph, and max tonnage is 5million a year. A-B will be about 5m a year.

Liverpool Street I believe has wooden sleepers because it was easier to install in the space and possession time available even though it has a shorter lifespan than concrete.

It’s more about the complex pointwork in the throat - much easier to install, adjust and maintain on timber for that sort of layout (particularly 30 years ago!)

 

[Dunfanaghy Rd]

I might add that in relation to CWR, and its stability, the direct fastening of rail to concrete beats rail to baseplate to sleeper.
Pat

 

[hexagon789]

A few years ago (maybe as much as 10, I can't remember) there was a Network Rail press release about using recycled plastic sleepers. I contacted them for some further information (where are they being installed?) but never had a reply. The presence of a press release suggests they exist somewhere on the main line.

Perhaps as an experiment

Liverpool Street I believe has wooden sleepers because it was easier to install in the space and possession time available even though it has a shorter lifespan than concrete.

Yes, and where the ballast needs to be shallower for certain reasons it's also done sometimes

 

[themiller]

Reckon you're right. Anywhere else in the UK?

Ffestiniog Railway use milk bottles for new rail sleepers

The Ffestiniog Railway has announced that it is replacing the wooden sleepers with brand new plastic ones.

www.railadvent.co.uk

Extract of story...

In Rail issue 923 (current issue), page36 there’s an article on the flat crossing at Newark and describes the bearers as ‘fibre-reinforced foamed urethane’ (FFU).

 

[gimmea50anyday]

I’m sure I read an article in the PWI (Permanent Way Institute for those who don’t know) magazine that Newark flat crossing was relaid in plastic bearers. They had to have them spray painted brown, as otherwise they’d have been white when installed!

It was in a recent Rail Magazine, issue 923 page 36. The article mentions the difficulty in maintaining the busy crossing and the difficulties in building any diversion due to the proximity of the river Trent and the A46 and it doesn’t pass the Cost:Benefit analysis studies despite the known wider benefits, so the crossing which usually needs replacing every 15-20 years has had the wooden sleepers replaced in 2019 with FFU (Fibre Reinforced Foamed Urethane) sleepers which should last closer to 40 years

 

[snowball]

Further to the above discussion of the Newark flat crossing, the thread in the "Speculative Ideas" subforum about grade separation of the crossing has been reopened at my request, because of proposals to dual the A46 which may affect any future rail flyover proposal.

https://www.railforums.co.uk/threads/ideas-to-replace-the-newark-flat-crossing.187295/post-4989809

 

[Annetts key]

Hardwood bearers are used on some bridge structures simply because the bridge was only designed for that type. It’s not practical to use concrete and the cost of a custom design of steel sleepers is likely too expensive.

British Railways has used reinforced concrete bearers for plain line for many, many years. I don’t know for how long, but Western Region had a big push on this during the 1970s. Network Rail now uses reinforced concrete bearers for switches (points) and crossings and has done for years. But only for new junctions or when junctions are being relaid.

Steel bearers are not liked, and may have fallen out of fashion. Because they cannot be manually packed (they are like upturned horse troughs, if you jack them up, all the ballast falls out). So the only option is to machine tamp lines that have them. You will however find them on branch lines, freight lines and in places, even on main lines.

Hardwood bearers are still being installed on Network Rail lines, but only to replace rotten existing bearers. Mostly on branch, freight lines or other low speed, low traffic areas. Especially where it is difficult to justify the cost of relaying using concrete bearers.

And there are still lots and lots of switches (points) and crossings which use hardwood bearers, simply because you are not supposed to mix and match concrete with wood on the same S&C. So until the junction is relaid, it will stay wood.

 

[Bald Rick]

Hardwood bearers are used on some bridge structures simply because the bridge was only designed for that type. It’s not practical to use concrete and the cost of a custom design of steel sleepers is likely too expensive.

British Railways has used reinforced concrete bearers for plain line for many, many years. I don’t know for how long, but Western Region had a big push on this during the 1970s. Network Rail now uses reinforced concrete bearers for switches (points) and crossings and has done for years. But only for new junctions or when junctions are being relaid.

Steel bearers are not liked, and may have fallen out of fashion. Because they cannot be manually packed (they are like upturned horse troughs, if you jack them up, all the ballast falls out). So the only option is to machine tamp lines that have them. You will however find them on branch lines, freight lines and in places, even on main lines.

Hardwood bearers are still being installed on Network Rail lines, but only to replace rotten existing bearers. Mostly on branch, freight lines or other low speed, low traffic areas. Especially where it is difficult to justify the cost of relaying using concrete bearers.

And there are still lots and lots of switches (points) and crossings which use hardwood bearers, simply because you are not supposed to mix and match concrete with wood on the same S&C. So until the junction is relaid, it will stay wood.

Pedantically, ‘bearers’ is a term for sleepers that are under S&C, or where there is longitudinal support, usually on bridges or viaducts.

For a relatively easy to understand explanation of steel sleepers, the linked presentation is excellent, albeit in my view a little too ‘steel sleeper happy’. It’s way too large to quote (sorry).

https://www.thepwi.org/technical_hub/technical_hub_files/section_meeting_presentations/16_september_2020_-_steel_sleepers_-_why_wouldnt_you_-_tom_wilson_jim_watson

 

[73128]

Recent TFL Board papers mentions (on page 61 about two thirds of the way down) new eco-friendly sleepers being laid on the LU Bakerloo LIne and subsurface routes.

Board Agenda Pack 3 February 2021 (tfl.gov.uk)

 

[Mcr Warrior]

If they are the plastic composite ones already mentioned upthread, suppose that makes good headlines, but possibly they aren't that widespread used, yet.

 

[Ploughman]

Any idea as to the current cost of a fully fitted Fastclip Steel Sleeper?
And a G44 Fastclip?

 

[Master Cutler]

I could never comprehend why wooden sleepers were replaced with concrete on many colliery lines back in the 1980s.
Our local Silver Hill Colliery branch line was upgraded from wood to concrete just after the connection to Pleasley Colliery was closed in the 1980s.
The line was completely closed in the 1990s meaning the concrete sleepers were only down for about 10 years and most ended up strewn about the embankments until the Teversal Trails were put in place during the early 2000s.

 

[Bald Rick]

Any idea as to the current cost of a fully fitted Fastclip Steel Sleeper?
And a G44 Fastclip?

Ahh - but what is ‘cost?’

1) cost of buying a sleeper, assuming bulk purchase (concrete is cheaper)
2) all up cost of installation, assuming low tonnage and bottom ballast in reasonable condition (steel is cheaper)
3) whole life cost. (It depends...)

 

[Deepgreen]

In the UK, it seems that concrete (or steel) are synonymous with welded rail, yet in most of the rest of Europe sleepers are still largely wood.

Why is this?

The short answer is - it isn't.