Water depth limit reasons?

[Morpethcurve]

What is the limit, and what is the limiting factor?

Is it splashing of the traction motors? The need to see the track in order to see subsidence? Braking ability?

Can anyone refer me to a Youtube vid of a train on submerged rails at high speed? I've often wondered what the spray pattern looks like.

Many thanks - Regards - Morpethcurve

 

[YorkshireBear]

What is the limit, and what is the limiting factor?

Is it splashing of the traction motors? The need to see the track in order to see subsidence? Braking ability?

Can anyone refer me to a Youtube vid of a train on submerged rails at high speed? I've often wondered what the spray pattern looks like.

Many thanks - Regards - Morpethcurve

Cannot refer you to a video. But i believe once it is (i want to say between 2 and 5 inches) above rail level then you cannot confidently say that the water has not eroded to trackbed. IE you dont know what you are driving over and that is the limit.

 

[The Planner]

I thought one of the biggest concerns is whether the water is moving across/through the ballast or it is standing?

 

[Erniescooper]

I came across this video http://www.youtube.com/watch?v=oddL3Jpn6UI last year and I think it is a guide on how not to drive through a flood as if I remember correctly he quickly grinds to halt having washed a brake pipe off.
From an engineering point of view you definately don't want to be going above axle box level or too much spray because if you contaminate the wheel bearing grease you are looking at wheel set change and from recent experience on a 3 car DMU you are looking at a £100,000 bill.

 

[carriageline]

If the water is up to the bottom of the railhead, trains run normally

Up to the top of the railhead, trains run at 5mph.

Above the railhead, and it's stop the job until Ops Control authorise otherwise.

The Planner is also correct, if the water is moving AND likely to dislodge ballast/has dislodged ballast them stop the job.

 

[transmanche]

Can anyone refer me to a Youtube vid of a train on submerged rails at high speed? I've often wondered what the spray pattern looks like.

This is from Argentina. Just see how it sprays water over the cars on the bridge. And I'm fairly certain that the driver won't be able to see see anything of the view ahead...

[youtube]B_NE2IaL37E[/youtube]

 

[SWTCommuter]

Here are a couple of clips of diesel hydraulics coping with quite deep water in Thailand. Not going all that fast though

http://www.youtube.com/watch?v=ftPBz0a9FJg&feature=youtu.be&t=15s
http://youtu.be/BIJd_FDpQQQ

 

[thebigcheese]

I thought it was to do with the issue of debris floating in water...if it's above rail hight and a log floats onto the track then it could create a derailment possibly???

 

[ainsworth74]

Not really if the water is that deep then the main concern would be the structural integrity of the whatever the rails are laid on. Ballast being washed away for instance.

 

[transmanche]

Not really if the water is that deep then the main concern would be the structural integrity of the whatever the rails are laid on. Ballast being washed away for instance.

Is it likely that we'll see more concrete slab track at 'high risk' locations in future?

 

[Chrisgr31]

This is from Argentina. Just see how it sprays water over the cars on the bridge.

Let alone over the pedestrians waiting to cross!

 

[carriageline]

Is it likely that we'll see more concrete slab track at 'high risk' locations in future?

I doubt it. If it's still up to the rail head then we still run at 5mph, or nothing at all if it's over!!

 

[YorkshireBear]

Is it likely that we'll see more concrete slab track at 'high risk' locations in future?

Doubt it as you then also worry about the embankments.

 

[transmanche]

I doubt it. If it's still up to the rail head then we still run at 5mph, or nothing at all if it's over!!

I was thinking more about ainsworth74's point about the "structural integrity of the whatever the rails are laid on". And specifically his comment about "ballast being washed away". So not so much about keeping the service going, but more about ensuring that as soon as the water level falls, the trains can start moving again - without having to go relaying the tracks first.

Concrete slab track would seem to be one way of dealing with that in "known trouble spots".

 

[The Planner]

How deep are the slabs? surely they can still be washed out from underneath leaving a slab in mid air which could snap?

 

[455driver]

How deep are the slabs? surely they can still be washed out from underneath leaving a slab in mid air which could snap?

And close the line for a week while its fixed.

Ballast might be washed away a bit easier but it is a lot quicker to fix afterwards.

 

[transmanche]

Ballast might be washed away a bit easier but it is a lot quicker to fix afterwards.

That's why I asked the question.

So the general feeling is that there aren't any situations where sections of concrete slab track would be useful at dealing with known flooding trouble spots?

(As an aside, in what situations does concrete slab track offer an advantage? I noticed that quite a bit of it was used around Dalston Junction, when that route was re-opened.)

 

[No Fault Found]

If a train goes through deep water, the driver should report it to maintenance control.

When that train goes in for servicing that evening, all axle box covers should be removed to check for water ingress. If water has found it's way in the axlebox then further inspections would be carried out.

If left with water in the axlebox, the grease will emulsify causing lack of lubrication, overheating and ultimately, bearing failure.

 

[30907]

Electric current is also an issue.

Clock House on the Mid Kent used to flood regularly and an emergency steam shuttle could be run when the current had to be off (later I think a class 33 plus "dead" EPB).

Hence no trains on Staines-Windsor now!

 

[LateThanNever]

I was thinking more about ainsworth74's point about the "structural integrity of the whatever the rails are laid on". And specifically his comment about "ballast being washed away". So not so much about keeping the service going, but more about ensuring that as soon as the water level falls, the trains can start moving again - without having to go relaying the tracks first.

Concrete slab track would seem to be one way of dealing with that in "known trouble spots".

In Dawlish the ballast was glued - although with the wall disappeared that didn't help - but the section further west is fine (apart from the debris)!

 

[jopsuk]

presumably floods can cause track circuit failures and wreck axle counters?

 

[455driver]

In Dawlish the ballast was glued

Are you sure?
The steel plates over the ballast south of Dawlish station and the way the waves were moving the ballast around North of the station suggests otherwise!

 

[edwin_m]

Ballast might be washed away a bit easier but it is a lot quicker to fix afterwards.

Probably also easier to see whether the ballast is OK than to see whether there are any voids underneath the concrete slab.

 

[181]

This thread makes me think of this picture; the same search brought up this one showing Wraysbury in 1947.

A video taken on board a German train passing through seawater can be seen here; you don't see what's pulling the train, but Wikipedia suggests that the traction is probably a small diesel locomotive like this or this.

 

[LateThanNever]

Are you sure?
The steel plates over the ballast south of Dawlish station and the way the waves were moving the ballast around North of the station suggests otherwise!

Some of it definitely - Tried moving it! But if the seas were shifting a cemented wall I'm sure they'd make short shrift of glued ballast too!

 

[455driver]

The ballst moves quite a lot anyway, just look at the down line after a few big waves and the way the ballast piles up against the right hand rail to the point that the wheel flanges will be hitting that ballast.!

 

[Murph]

The ballst moves quite a lot anyway, just look at the down line after a few big waves and the way the ballast piles up against the right hand rail to the point that the wheel flanges will be hitting that ballast.!

Gravels can pretty much be considered to be high density, high viscosity fluids for many purposes. That's pretty much the mechanism which allows that movement (fluid dynamics), with the sleepers effectively floating on top of it.

 

[Morpethcurve]

This from a 1960 Operating Manual for BR Locos D11 - D137:-

"RUNNING THROUGH WATER

If the water is deep enough to touch wheel flanges, speed must be restricted to 5 m.p.h.

The locomotive, however, should not be driven through water deeper than 4 in. above the top of the rails"

Regards - Morpethcurve