UK Quad Tracking

[Gangsta_Boi]

Hi all,

I Have a slight dilemma over the use of UK Quad Tracking, not sure how to word this so please, look at the following diagrams

--->
<---
--->
<---

OR

--->
--->
<---
<---

(using standard uk left hand driving) (arrows show diection of travel)

Could you please tell me which is correct ?

P.S What is the spacing between the two middle tracks ?

Thanks guys !

Gangsta_Boi

 

[gliderboy]

I believe its the first option. it allows for left hand signals to be placed in the middle without fouling the trains. The standard Auran 4 track will only let you do it so that it looks OK in your top configuration.

If anyone else knows better tell me.

Dave

 

[Gangsta_Boi]

Wow that was fast ! silly me, i could have looked it up on Wikipedia, but please, continue posting your thoughts/answers

Thanks

Gangsta_Boi

EDIT: I can't find anything on Wiki

 

[clockwork_orange]

I would have guessed at the second arrangement, with the outer track being the "slow" lines and the inner tracks being the "fast" lines. However, I am certainly no authority on UK rail operations, so it's quite possible I am wrong.

Regarding signalling, if you were using the second arrangement you might use gantry signals, brackets, or cantilevers to overcome a lack of space.

Regarding spacing, I understand that the middle gap is wider than the UK standard 3.5m where space allows, but I am unsure of how much wider. I would guess at a spacing of 4 to 4.5m between the centres of each track.

 

[Gangsta_Boi]

Thanks Clockwork_Orange, any help is appreciated, also, just a thought, anyone have documents, drawings, website links on this ?

Thanks,

Gangsta_Boi

 

[insulfrog]

Since I am in the Simsig community as well as Trainz, I am able to answer your query.

These are diagrams that I grabbed from a couple of sims, they basically show 3 possible combinations of quad track configurations.



Hope this helps.

 

[AndyM77]

Hehehe, not to confuse matters but there are also reversable lines!

On train based forums I see references to the "4 foot", so I'd guess that is the spacing between tracks

 

[paulzmay]

The short answer is both!

If I recall rightly, the southern section of the West Coast Main line is like option 1, and the southern section of the East Coast Main line is option 2. I'm not familiar enough with other stretches of 4 track main line to remember them...

@insulfrog - I can't see your diagrams - what's the third configuration?

Paul

p.s. - I can now! Ignore me...

 

[Gangsta_Boi]

WOW ! Thanks guys ! i suppose i could go with option 1 as they are all fast lines, is this correct ?

Sorry about having so many questions

Gangsta_Boi

 

[steviez]

Well your all right,
there are various methods of 4 track working
diagram 1
would be up fast, down fast,up slow or goods,down slow or goods (depending on its designation as a passenger line or goods only)
to run a passenger train over goods lines you had to have special permission.


diagram 2
would usually be up slow/goods, up main/fast, down main/fast down slow/goods

Take for example London St Pancras to Nottingham currently,
Its 4 track all the way from just Nth Of Pancras through to Glendon jcn
As per your diagram 1 (the 2nd pair of lines then go via Corby, Harringworth viaduct as goods lines through to Manton jcn where it becomes the Peterborough-Leicester passenger line to Syston jcn

But between Beeston and Nottingham the tracks are set out as per your diagram 2 i.e with the loops/goods/slow lines on either side of the main line so even on the same stretch of line both can occur.

Another example is Derby-Birmingham New st which in 30 odd miles has both either side and in pairs at various points

Its actually a lot more complicated than that but i have tried to give a simplistic illustration
other elements to differentiate slow/goods lines in these days of power signalling are speed over the slow/goods line, signalling distances, signal head if its 3 aspect or 4

i could go on lol

 

[lewisner]

The first method is known as "Paired By Speed" and was commonest on LMS lines (eg WCML) and the second was known as "Paired By Direction" and commonest on the LNER (eg ECML) and SR.The second also has advantage of requiring less complicated trackwork at junctions , obviously when you want a train to cross from the slow to the fast...

 

[steviez]

I am sure that the LNWR creators would turn in their graves at the the shock of calling the WCML a Midland route lol!!
but yes Lewisner you are right as well , some of the formations were dictated by different companies joining at junctions and having seperate lines to a common station and also by traffic levels, the goods lines south of Trent Station were put there between 1879-1884 due to the amount of goods mainly coal from the Midlands destined for London and Sharnbrook summit was tunneled under to give better grades on the goods lines for London bound loaded traffic.

 

[lewisner]

"Steviez" "Midland" = Midland Railway (pre 1923)."LMS" = London Midland and Scottish Railway (post 1923) The LMS owned the WCML after 1923.

 

[steviez]

Sorry i beg to differ
The WCML was owned by the LNWR 1846-1923
i refer you to the railways of Great Britain ( a historical atlas) by Colonel M.H.Cobb which lists All railway lines between 1807-1994 annotated with historical detail.

 

[lewisner]

What do you beg to differ on? I said "LMS Lines (eg WCML". I never mentioned the Midland.THE WCML was owned by the LMS from 1923 - 1948 and by British Rail from 1948 - 1996.

 

[davidbird]

As another variation, although it never actually happened..

The Great Central's London Extention, through Nottingham Victoria, Leicester, Rugby etc,. to London Marylebone was double track. Almost all the stations were built with island platforms with passenger access from subways or over-bridges. This was to allow fast lines, for non-stop expresses to by-pass stations, to be built at a later date without needing to alter station platforms at all.
So they would be "paired by direction" like the rest of the LNER, but
---> Up fast
---> Up slow
<--- Down slow
<--- Down fast.

Unfortunatly the GC came too late and 4-tracking was never needed...

If only...