UKs sharpest gradient change?

[LucaZone]

Saw this pic and it got me thinking. http://www.trainpics.net/p62111415.html

How fast would a train need to go to 'jump' the rails?

Are there other sharp gradient changes around the UK?

Cheers
Adam

 

[EltonRoad]

I quite like this one from Alan Mitchell:

http://alanmitchell.fotopic.net/p44429987.html

and the ones before and after it.

 

[SWT Driver]

That'll be at Blackfriars.

If I remember it's a short gradient of 1:37.

 

[37401]

Saw this pic and it got me thinking. http://www.trainpics.net/p62111415.html

How fast would a train need to go to 'jump' the rails?

dunno but it would be fun finding out , id say a good 10-20mph over the limit maybe

 

[Old Timer]

Its not the longer gradient changes that are the problem, because it is almost impossible to create the vertical change necessary to bring about a derailment.

The risk of derailment is associated with what is known as "twist" best explained as being like a shopping trolly which has a twisted frame such that one wheel is off the ground.

If you reverse that principal, so that the rail vehicle is rigid, but the track is distorted, then you will see that a wheel can come out of contact with the rail.

This is known as "Wheel Off-Loading".

Whilst it is posibble for a rail vehicle to pass over a distortion in vertical rail level, any forces acting in a sideways manner which cause the vehicle wheel to to move outwards towards the point where the rail is lowest will result in derailment.

 

[Navviboy]

best explained as being like a shopping trolly which has a twisted frame such that one wheel is off the ground.
.

It's not just me that picks the rougue troliies then OT. Had one the other week that would probably have been a "block the line" jobbie!

To add a bit more detail to gradient changes. Just as a railway has a horizontal design for curvature, so it has a design for vertical profile. This will design a curve into the gradient change in such a fashion that the resultant formation doesn't resemble anything from Blackpool Pleasure Beach!

 

[Old Timer]

Navviboy.

Try this one for size. Coming to a site near you....soon !

Seeing this in the distance I thought it was a buckle and went to investigate.

Here is what I found.

Not a buckle but a new run out into existing. This is a 40 mph passenger line.


One for the Tamper lads.

 

[A60K]

That really does look like badly joined model railway track! I'm amazed that the worksite supervisor felt able to sign that off.

 

[Old Timer]

Signed off, handed back to traffic, accepted by NR.

I once dismissed a man for trying to hand back something much better but which was still not in compliance.

 

[Vlad the Impaler]

OT,


Nice bit of running out into the existing there NOT!!

No attempt to blend it in to the existing by the look of it, guess the next tamper in on follow up over the next few nights (if there was one of course!) was not asked to put the lining right either

Mind, looks like they had to squeeze the six foot under the bridge a tad, which made it worse when they ran into the old.....tad to much stone under the bridge, meaning tight clearance chaps???


Re the tamper pic - ...guessing at a unimat from the way its laid out, with s&c about with the two bods in the chair(s).???

(only guessing as not allowed to play with the really big boys toys yet, just plain liners at the mo :cry

V

 

[Old Timer]

You cannot see it in the picture, but the track dips through the O/B then is aligned laterally and vertically into the existing.

It is unbelievable that this was ever handed back in such a condition.

 

[mumrar]

Whilst not being able to derail a train, the sharpest gradient changes in the UK will be found on the high speed CTRL.

 

[SWT Driver]

Are there any greater than the 1:37 at Blackfriars though?

 

[djw1981]

We are talking of gradient change though so the 1:37 may become 1:7- 1:140 etc until level. If it went 1:37 - level - 1:37 the other way in say 20m thats sharp.

 

[Mojo]

How steep is the section just after you leave the 'a' end of New Street, heading towards Proof House? http://www.trainpics.net/p58433170.html

 

[Old Timer]

There are guidelines on gradient changes both in terms of the minimum and maximum RATE of change, as well as the minimum distance between gradient changes.

For example it is undesirable for a gradient to change more than once under a vehicle, for obvious reasons.

On heavy haul freight lines, the restriction on multiple gradient changes is principally that only one gradient change is permitted underneath the train, and this may only consist of a positive or negative gradient leading to a 0 gradient (level).

In one case that comes to mind, there is a prohibition placed on gradient changes taking place with 4 Km of each other, as this is the length of the train plus a slight margin !

The reason for this is so that the train is not compressed at one end whilst being stretched at the other end. So far it has not become a problem in the UK because of the (relatively) short length of our trains in comparison to both Europe and the Americas.

For obvious reasons these prohibitions impose considerable difficulties when track renewal is taking place, more especially when on Heavy Haul freight lines, Renewal time is measured in the hours between trains with little or no opportunity to work within an extended Possession.

 

[Phoenix]

How steep is the section just after you leave the 'a' end of New Street, heading towards Proof House? http://www.trainpics.net/p58433170.html

I noticed that one today although the gradient begins to level out after something like 100 yards it is a pretty steep drop I was on the XC HST today and was watching a pendo sitting in the same position.

 

[SWT Driver]

I've found these pictures on railfaneurope website, it sort of shows you the gradient involved.

I acknowledge the copyright on them and if the owner objects to their use then please contact a moderator to get them removed.

SWT.

 

[Old Timer]

The gradients at Blackfriars and at Proof House Jct are quite severe and not a million miles different.

I recall something around 1 in 50 or 1 in 37/35ish for Proof House Jct. but until I can get back home and dig out some signalling plans I cannot be certain.

As for Blackfriars well I would certainly go with SWT Driver.

Phoenix
The retaining walls, plus the height of the buildings, plus the additional running lines do certainly give one a feeling of going down into the earth from Proof House into the Derby and Stour tunnels outside New St. I think the greater gradient however is on the Down Vauxhall Fast lines where the Aston lines run over the Up Stour.

Its a bit like Alton Towers there !

 

[CCF23]

Not National Rail but the deep mine at Llechwedd slate caverns in Blaenau Ffestiniog has the steepest railway in Britain, 1 in 4.

On the Underground the steepest gradient in passenger use is on the District and Hammersmith and City lines just east of Bow Road where the line surfaces and meets the c2c line from Fenchurch Street, this is a 1 in 32 although the steepest overall is on the approach to Northumberland Park depot on the Victoria Line, not in passenger use which is a 1 in 28 gradient.

On National Rail as previously said Blackfriars is very steep.

Chris

 

[Oracle]

What's the gradient to London Road Depot? I confess to having 'bashed' Nothumberland Park Depot reception roads on the Auto-Tube Rambler tour.

 

[Saltleyman]

The gradients at Blackfriars and at Proof House Jct are quite severe and not a million miles different.

I recall something around 1 in 50 or 1 in 37/35ish for Proof House Jct. but until I can get back home and dig out some signalling plans I cannot be certain.

I think you will find that the gradient from Birmingham New Street drops at 1 in 113 down to level for a very short distance and then rises to Proof House Junction at 1 in 51.

 

[Old Timer]

Thank you Chap, your word will do for me !

 

[Phoenix]

The gradients at Blackfriars and at Proof House Jct are quite severe and not a million miles different.

I recall something around 1 in 50 or 1 in 37/35ish for Proof House Jct. but until I can get back home and dig out some signalling plans I cannot be certain.

As for Blackfriars well I would certainly go with SWT Driver.

Phoenix
The retaining walls, plus the height of the buildings, plus the additional running lines do certainly give one a feeling of going down into the earth from Proof House into the Derby and Stour tunnels outside New St. I think the greater gradient however is on the Down Vauxhall Fast lines where the Aston lines run over the Up Stour.

Its a bit like Alton Towers there !

I always quote Proof house and the lines going from the south into new street as the 2nd spaghetti junction.
But yeah you can clearly tell the design stages of Birminghams railways were a drunken affair

 

[Pumbaa]

DLR? Some pretty mental gradients there from Westferry over to West India Quay.

 

[mumrar]

Sticking to adhesion based railways, on the High Peak network in Derbyshire there was a 1 in 18, think it's called Hopton incline? Freights had to be split at the bottom and trip worked up in sections.

 

[TDK]

1 in 36 - 1 in 100 at Stafford Rd.Jct (Oxley)
1 in 43 down - to 1 in 55 up at the London end of New Street Tunnel

These are pretty severe,

 

[Old Timer]

I always quote Proof house and the lines going from the south into new street as the 2nd spaghetti junction.
But yeah you can clearly tell the design stages of Birminghams railways were a drunken affair

You will possibly find the following links quite interesting as the history of New St explains why the track layout has developed as it has.

http://forum.birminghamhistory.co.uk/showthread.php?p=83358

This link has some excellent photographs
http://www.photobydjnorton.com/NewStreetStation.html

http://en.wikipedia.org/wiki/Birmingham_New_Street_railway_station

 

[furryfeet]

Sticking to adhesion based railways, on the High Peak network in Derbyshire there was a 1 in 18, think it's called Hopton incline? Freights had to be split at the bottom and trip worked up in sections.

The 1 in 14 is probably the contender for the title, if closed railways are included. On that basis, can anyone say what the gradient change was at Bury Knowsley St. for trains going to and from Bolton ?
( someone on the East Lancs Rly will know )

speaking of the East lancs, the "ski jump" over the metrolink must have a fair gradient change,since it is 1 in 29 one way and 1 in 58 the other !

 

[O L Leigh]

http://weirdy49.fotopic.net/p39204544.html

O L Leigh