Drogheda Viaduct

[Barl]

I'm not sure if this has been posted before but I received this link from a colleague who worked on the renovations of the Drogheda Viaduct and it shows some nice drone captured footage.

 

http://www.irishtimes.com/dramatic-drone-footage-of-the-refurbished-drogheda-viaduct-1.2458554

[jhb171achill]

It's turned very green. Did they rebuild it in copper?

[Junctionmad]

That lighting has all the taste of a seaside arcade

 

By the way , is the track work still gaunt, or now conventional

[jhb171achill]

Still gauntletted.

[Junctionmad]

It looked more like a check rail , then gauntlet track work. That's why I asked.

[jhb171achill]

That's what I thought too, junctionmad. But I checked with someone in IE.

[Garfield]

That's what I thought too, junctionmad. But I checked with someone in IE.

 

I thought the track arrangement was simplified a few years back, no? Single track with a a 'Y' point at either end...

 

Edit: Photo taken last year shows it's single track with check rails -

Edited December 18, 2015 by Garfield

[Horsetan]

I thought the track arrangement was simplified a few years back, no? Single track with a a 'Y' point at either end...

 

Edit: Photo taken last year shows it's single track with check rails -

 

I think you are correct on that one. The interlaced track was removed, apparently over a decade ago.

[Old Blarney]

Having viewed this video repeatedly, I am of the opinion:-

 

1) The innermost two rails have no sheen on them.

2) The two outermost rails have a sheen on them.

 

These two facts suggest the outermost rails are the running rails and the innermost two are check rails. There are no other rails to protect a train in case of a derailment whilst traversing this structure. This being the case, the innermost two sets of rails are therefore - check rails!

[jhb171achill]

News to me, if it is, and if so my source (within ironroad Éireann) isn't up to date either!

 

I'll make definitive enquiries.

[Horsetan]

Also, the part of the film which shows the train exiting from the viaduct pans back to show it approaching a "Y" point....

[jhb171achill]

Maybe it is single track, then....

[Mike258747]

I think that the interlaced, or gauntlet, track was removed about 15 years ago. I remember reading about it at the time but I am not sure of the exact date.

[josefstadt]

News to me, if it is, and if so my source (within ironroad Éireann) isn't up to date either!

 

I'll make definitive enquiries.

 

The interlaced track across the Boyne Viaduct was taken out of use on the night of the 2nd/3rd March 1997, following the passing of the 20:15 Dublin-Belfast service.

[Glenderg]

[josefstadt]

That's the situation prior to the 1997 work. As part of the re-modelling the start of the interlaced track was replaced by a turnout and the rails of the former Up line across the viaduct were removed. Also, the facing crossover (closer to the camera) was removed.

[jhb171achill]

In that case, I stand corrected!

[burnthebox]

Thanks Barl for posting that, enjoyed it btw mind telling me who counted the rivets !! all 14,000 !

Edited December 19, 2015 by burnthebox

[Mike258747]

Any other examples of interlaced track in Ireland? It is common on tramway systems on mainland Europe.

[DiveController]

Nice shot, Richie!! It looks like this has an interlaced up and down line with check rails on the inside also.

 

What would the advantage of an interlaced track (versus merging into a single road) have been? Absence of a facing point at the exit to the bridge in each direction?

Edited December 19, 2015 by DiveController

[jhb171achill]

I'm unaware of any in Ireland, bar the instances discussed on another board about 5ft 3 track being interwoven (as dual gauge) with 3ft gauge, as at places like Larne Harbour...

[Junctionmad]

Nice shot, Richie!! It looks like this has an interlaced up and down line with check rails on the inside also.

 

What would the advantage of an interlaced track (versus merging into a single road) have been? Absence of a facing point at the exit to the bridge in each direction?

 

Yes that's exactly the advantage

[Maitland]

I got out my private helicopter (kindly supplied by Google Maps) and took a flight over Drogheda just now. There are points either end of the viaduct, so it's ordinary single track. I don't know the technical term for the safety rails, they aren't check rails as such which are set just inside the back-to-back gauge. You see them on a lot of bridges though.

[tonybonneyba]

I got out my private helicopter (kindly supplied by Google Maps) and took a flight over Drogheda just now. There are points either end of the viaduct, so it's ordinary single track. I don't know the technical term for the safety rails, they aren't check rails as such which are set just inside the back-to-back gauge. You see them on a lot of bridges though.

 

Guide Rails are the technical term

[josefstadt]

Guide Rails are the technical term

 

They are 'Guard Rails'.

[DiveController]

Yes that's exactly the advantage

 

 

So I wonder why they needed interlaced track then but in this age of health and safety and high viz vests and ….

Well, why go with to a facing "Y" point now?

Are modern points more reliable with regard to absence of potential derailing, someone decided it had been unnecessary in the first place on safety grounds, or what?

The bridge is no lower now and I presume if the bridge itself was not going to 'hold' a derailing loco then it would not do any better job now. We did have a discussion about facing points and modern stiffer track on another thread here in the last year or so but I'm not sure if any of that factors into this?

 

Was the interlaced track controlled by a token/key as there were separate up down lines but these would normally overlap/interlace as here?

 

Were the tracks interlaced because bridge was too narrow or could not support the weight of two trains on the bridge simultaneously?

[Junctionmad]

They are 'Guard Rails'.

 

The term guard rails and check rails are interchangeable , with " guard" rail being primarily US rail terminology.

[Junctionmad]

 

So I wonder why they needed interlaced track then but in this age of health and safety and high viz vests and ….

Well, why go with to a facing "Y" point now?

Are modern points more reliable with regard to absence of potential derailing, someone decided it had been unnecessary in the first place on safety grounds, or what?

The bridge is no lower now and I presume if the bridge itself was not going to 'hold' a derailing loco then it would not do any better job now. We did have a discussion about facing points and modern stiffer track on another thread here in the last year or so but I'm not sure if any of that factors into this?

 

Was the interlaced track controlled by a token/key as there were separate up down lines but these would normally overlap/interlace as here?

 

Were the tracks interlaced because bridge was too narrow or could not support the weight of two trains on the bridge simultaneously?

 

Complex track work is an anathema to modern rail companies and especially IE. Modern tamping machines. Etc also dictate the use of simple track work and modern turnouts are pre fabricated virtually like hornby set track.

 

The bridge was singled in the 1920s when the centre arch was replaced.

 

I presume that the signalling merely treated guantletted track as n a similar way to the current arrangement, with a one train in section approach

[Dhu Varren]

Were the tracks interlaced because bridge was too narrow or could not support the weight of two trains on the bridge simultaneously?

 

The original bridge had had double track, but was worked as a single line to avoid having two trains on the bridge at the same time.

 

When the bridge was replaced in the early 1930s, the line was temporarily singled for the duration of the work, and the new bridge was built inside the old one. This then meant that the new bridge was too narrow for double track, but since there had a restriction on having two trains on the bridge at the same time for many years, the provision of gauntleted double track was not a problem. On completion of the new bridge, the old bridge was then dismantled.

[Maitland]

Are modern points more reliable with regard to absence of potential derailing

 

Generally they are - if they are looked after. See "Grayrigg" https://en.wikipedia.org/wiki/Grayrigg_derailment.

[DiveController]

Thanks, David & Maitland.

I remember Grayrigg now that you mentioned it. Completely preventable, 5 years for the furore to die down, a paltry slap on the wrist (no, £4m isn't really that much (and better spent on track maintenance, I know)), and a knighthood to boot.

Spectacular!

[Broithe]

August 2016.

 

 

[jhb171achill]

Beautiful photo, Broithe.

[Broithe]

Beautiful photo, Broithe.

 

Not mine - pinched from Twitter - see the link...