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Speed restrictions as the heatwave arrives

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Darandio

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What, like NR were aware of the heatwave forecast days in advance yet all they could come up with was this contingency plan of speed restrictions?

Presumably they should have hired in Mr Freeze?
 
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Agent_c

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FGW are probably the most creative of all TOC's when it comes to finding reasons not to run trains! So the points for both Marlow and Henley branches are for some reason more susepable to heat than all the other points in thus area! My bet it is summertime, there is a shortage of train crews/stock and FGW had to find an excuse as why they have had to cancel services!

HC

If however its connecting to a train that is on (and will remain on) a branch line, wouldn't that suggest that more staff would be needed to run the overall service (original train and new train).
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I live in South Australia, one of those other places where the conditions for the rails are much tougher. After a lengthy period of track rebuilding, our suburban network is now at the point where we don't get rail-related disruption even when the maximum temperature is into the mid 40s. When things do start going wrong, in general the problems we do get are equipment failures rather than issues with the rails.

Your rails there will be "tuned" for higher temperatures when accounting for expansion/contraction based on temperature.. If there was to suddenly be a cold snap such that Australia doesn't see outside of the Skifields, You could expect problems to occur that a British section of track would be quite happy with (after the snow had been removed of course).
 

westv

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Ultimately though it doesn't matter how many logical reasons are given Joe Public (after a hard day at work, has his normal train cancelled so has to endure the next boiling hot and overcrowded service which then runs late) is going to wonder what's going on. The rail industry is in a no win situation whatever. It might not be right but that's the way it is.
 

meridian2

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Ultimately though it doesn't matter how many logical reasons are given Joe Public (after a hard day at work, has his normal train cancelled so has to endure the next boiling hot and overcrowded service which then runs late) is going to wonder what's going on. The rail industry is in a no win situation whatever. It might not be right but that's the way it is.

Hardly; the shareholders might disagree with you there.

I have no axe to ginnd with NR, the problem is lack of forward planning when the Met Office has forecast this heatwave since last week. Even just informing passengers would've been enough.
 

Dave1987

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Ultimately though it doesn't matter how many logical reasons are given Joe Public (after a hard day at work, has his normal train cancelled so has to endure the next boiling hot and overcrowded service which then runs late) is going to wonder what's going on. The rail industry is in a no win situation whatever. It might not be right but that's the way it is.

That he/she pays thousands of pounds each year to use because they have no choice but to commute by rail etc etc etc....... Thought I would add that little bit you missed off in. There was a quote from a guy at Witham who said "there is always some excuse, wrong type of sun today".

I think one way that Network Rail could show the serious safety implications of not introducing the heat restrictions is by making some kind of film showing what would have if a train hit a buckled rail at full speed. Because those that are moaning about the speed restrictions would be the first to ask why there weren't any if there was a major crash.
 

6Gman

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Hardly; the shareholders might disagree with you there.

I have no axe to ginnd with NR, the problem is lack of forward planning when the Met Office has forecast this heatwave since last week. Even just informing passengers would've been enough.

So if the TOCs had announced a few days ago that "services will be subject to potential cancellation and delay in the event of high temperatures" you would have been satisfied?
 

Dave1987

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Hardly; the shareholders might disagree with you there.

I have no axe to ginnd with NR, the problem is lack of forward planning when the Met Office has forecast this heatwave since last week. Even just informing passengers would've been enough.

You seem to have a real axe to grind about privatisation though but I'm sure that a nationalised railway would have coped perfectly on the hottest July day on record in Britain :roll:

They do have forward planning, they responded to the forecast by implementing safety blanket speed restrictions. What more could they possibly have done?
 

dviner

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I think one way that Network Rail could show the serious safety implications of not introducing the heat restrictions is by making some kind of film showing what would have if a train hit a buckled rail at full speed. Because those that are moaning about the speed restrictions would be the first to ask why there weren't any if there was a major crash.

Why bother? The response would be that NR should have planned for this, and got its thousands of overpaid track workers out there to re-stress the rails before it could happen.

Sorry. Forgot the <sarcasm> tags there.
 

Dave1987

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So if the TOCs had announced a few days ago that "services will be subject to potential cancellation and delay in the event of high temperatures" you would have been satisfied?

And then if temperatures didn't quite hit over 30 degrees they would have been accused of over reacting.
 

meridian2

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So if the TOCs had announced a few days ago that "services will be subject to potential cancellation and delay in the event of high temperatures" you would have been satisfied?

But they were still caught out, just look at the number of imposed speed restrictions.

'NR can't win' is a bit disingenuous to say the least.
 

Dave1987

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But they were still caught out, just look at the number of imposed speed restrictions.

'NR can't win' is a bit disingenuous to say the least.

I'm very confused by your statement that they were caught out. They introduced speed restrictions during the hottest part of the day to prevent serious damage to the track. That's being proactive. There isn't much more they can do.
 

Bald Rick

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But they were still caught out, just look at the number of imposed speed restrictions.

'NR can't win' is a bit disingenuous to say the least.

Except that on Sunday, the forecast was for 30c max. You haven't answered the question - what alternatives do you suggest?

Anyway, NR control phoned Stephen Hawking this morning, and he confirms that, unfortunately, NR can't break the laws of physics, even for just a couple of days.
 

EM2

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But they were still caught out, just look at the number of imposed speed restrictions.

'NR can't win' is a bit disingenuous to say the least.
Is it? You need only look at the reactions when it was decided to pre-emptively suspend services well in advance of the big storms last year.
 

SpacePhoenix

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Does it make any difference when the trains are either longer but less frequent or shorter but more frequent?
 

Ediswan

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Not so. At this time of year, rail temps will be +18c above ambient in sunny weather, +15C in partly cloudy, +13C in full high cloud, and +8C in full grey cloud.

Thanks for that. Anybody who has accidenatally picked up a spanner that has been full sun knows the effect. Your post gives some hard to find numbers.

It seems to me (not a railway worker, but familiar with other complicated systems) is that what we have here is a system which, when faced with unusual extreme conditions, continues to deliver a gracefully degraded service.

The other basic options are: Pay £££££s extra for a capability that will rarely if ever be used; Shut down completely; Carry on regardless and risk a distinctly ungraceful degradation of the service.

The current approach works for me as both a passenger and taxpayer.
 

carriageline

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The only option to stop buckling rails (as I understand it, but I'm a mere signaller not a track engineer!) is to go out and restress all the track for a higher temp.

Now the problems with this:

1) man power, it would take a LONG time. Time that NR simply do not have, teams are occupied with more important tasks.

2) cost

3) what's the point for a week or two, soon as the temp starts dropping again it will have to be restressed so it doesn't crack when it contracts due to the lower temps.
 

LAX54

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Those comparing our railways with continental Europe are really comparing apples and oranges. For starters, their railways are run as a public service rather than to line pockets of shareholders, ergo, they are considerably more safer and well-designed to cope with all weather conditions.

"Wow there Neddy" ! I think you will find the UK Railways are by far the safest in the World, and by far the busiest! As for Hote weather, everyone in the media keep going on that it's the hottest day for 9 years, some say hottest day on record, then we are hotter than Brazil / Bali / Hawaii etc, then moan that because the heat is above what is really 'normal' in the UK Network Rail are trying to take precautions to minimise the effect of the heat !
other countries maybe run as a 'public service' but the level of that public service is very questionable !
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Well this morning we had problems with the OHLs at Colchester. That's another issue, especially on routes like the GEML, which has old wires along much of the route.

Faulty transformer which did not raise it's head until about 0500, this resulted in the GE stock being stranded in the c/sdgs, to start with the OHL was isolated from Marks Tey to the c/s Colchester on the Down, but due to the sterling work of the staff called out of their beds, this was shortened so that trains could run vai the DGL via P1 at Colchester. and temporary fix was done by about 1300 I think.
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What, like NR were aware of the heatwave forecast days in advance yet all they could come up with was this contingency plan of speed restrictions?

Of course they should have! close the network completely for about a week, restress all the track to take into account the unusual high temps, (not sure what you can do about the physics of copper wire on the OHL and heat) they can then run a near 'normal' service, then shut down again at the end of the heatwave, and restress again for cool Uk weather :) sorted :)
 

Boodiggy

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The only option to stop buckling rails (as I understand it, but I'm a mere signaller not a track engineer!) is to go out and restress all the track for a higher temp.

Now the problems with this:

1) man power, it would take a LONG time. Time that NR simply do not have, teams are occupied with more important tasks.

2) cost

3) what's the point for a week or two, soon as the temp starts dropping again it will have to be restressed so it doesn't crack when it contracts due to the lower temps.

Hi Signaller, Most track of will be correctly stressed its only sites with either inadequate stress or unknown stress where we have the issues. These sites will mostly be planned in before the onset of hot weather (from a Pway point of view that is 1st April). Most speeds that have been going up are at renewals sites or for low ballast or transient sites that are on for a set number of days following ballast being disturbed (tamping etc). All CWR track must be stressed and the standard States we stress it to a Stress Free Temperature of 27 degrees.
 

Bald Rick

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Most of these speed restrictions today are not to do with stress in the rails per se, but more because work has been done on the ballast in the last 5-10 days which reduces the fixity of the track alignment until the ballast has re consolidated under traffic.

In some case the restrictions are also due to the type of track (eg wooden sleepers) and/or curvature - tight curves are more likely to buckle.

The solutions are of course simple:

1) re stress the lot twice a year
2) slab it all
3) relay it all in a much thicker (and therefore stiffer) rail section
4) put it all under cover
5) stress to a higher stress free temperature, and accept a much higher incidence of broken rails in winter (many railways do this, particularly those that predominantly carry freight)
6) try to find the best Stress Free temperature that covers 99.9% of the likely temperature range, and accept that for the 0.1% there will be speed restrictions.

Guess which one causes the least disruption to passengers, and also has the lowest cost to the funders of the railway (farepayers and taxpayers, ie all of us).
 
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edwin_m

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There are plenty of other places with railways that have a much wider temperature range than Britain. How do they cope?

- Heavier or closer spaced sleepers?
- More ballast?
- Re-stressing the rail twice a year?
- Breather switches?
- Jointed rail?
- Something else?

Or do they just accept a greater level of risk?

Or do they all impose restrictions too, we just don't get to hear about them?

Pretty clear they don't consider slab track to be necessary, otherwise it would be much more widespread than it is in those countries.

Wouldn't heavier rail just actually make things worse by increasing the expansion forces?
 

DasLunatic

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Or, a cheaper and easier solution: add sprinklers that spray cool water onto the rails. It'll be just like driving in the rain. No restressing rails. No extra ballast - sorted cheaper.
 

alexl92

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I can agree with that, having looked out of the windows of my creaking 321 the other day to realise that NR have done absolutely no vegetation control on the GEML...

I heard somewhere that if NR had kept the lineside as clear as they're meant to then the whole WCRC steam ban in LM zone/lineside fire started by 5972 thing last year probably wouldn't have happened because the hot coal that started the fire which started the whole thing wouldn't have had anything to set fire to.

No idea if it's true though.
 

Bald Rick

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Or, a cheaper and easier solution: add sprinklers that spray cool water onto the rails. It'll be just like driving in the rain. No restressing rails. No extra ballast - sorted cheaper.

Not so good in areas with third rail. Or a long way from mains water.
 

Flamingo

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There was an experiment a few summers ago with having the rails kept wet to see if it kept them cool...
 

Bald Rick

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There are plenty of other places with railways that have a much wider temperature range than Britain. How do they cope?

- Heavier or closer spaced sleepers?
- More ballast?
- Re-stressing the rail twice a year?
- Breather switches?
- Jointed rail?
- Something else?

Or do they just accept a greater level of risk?

Or do they all impose restrictions too, we just don't get to hear about them?

Pretty clear they don't consider slab track to be necessary, otherwise it would be much more widespread than it is in those countries.

Wouldn't heavier rail just actually make things worse by increasing the expansion forces?

Well the thing is, there simply aren't that many railways that do have a wider range of rail temperatures than us. Even in the middle of the Australian desert, rail temps don't go much above 60C. Yesterday we had rail temps at 55C. And we have to go down to -15C and lower.

Most other railways either put speed restrictions on (eg most of France yesterday) or accept a higher incidence of buckles, broken rails and the consequences (eg the US railroads).

Breather switches don't help with CWR. They are solely for use at the join between CWR and unstressed sections.
 

infobleep

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i love the twitter feeds on the TOC twitter accounts which remind people to carry a bottle of water with them when travelling. thanks for stating the bloody obvious!
Well Southeastern were giving out free water bottles yesterday. Without any water though. I saw a picture on Facebook with a sarcastic comment to go with it.

I think the intention was for you to fill it up yourselves and reuse it. Not a bad idea.

As I've alighted I've just heard the water bottle announcement from South West Trains..

What annoys me if the concert venues that wouldn't let you take water bottles in or you have to remove the caps. Not helpful when following the public transport advice after the concert. There isn't always time afterwards or the facilities to buy water bottles either.
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Most renewals are to those specs these days but what you need to realise is most buckles are caused by ballast disturbance. It is not just a case of rails getting hot and buckling. Most heat related speed restrictions will be imposed at sites where ballast has been recently disturbed or the rail has inadequate stress. Also G44 sleepers use fastclips that have a higher toe load than pandol 401 clips or e1809 (eclips) that are used on older sleepers which means there is more resistance to expansion and contraction.
Every section of track will have a CRT (Critical Rail Temperature) and there are many factors that reduce this. An undisturbed site on concrete sleepers will hold up in the heat far better than track on wood sleepers etc. Also if a section of track is not stressed to the required temperature then this will effect the CRT. Low ballast has a very negative effect on CRT. For jointed track it is slightly different but again if a site has joints regulated properly it will have a much higher CRT than a site where the expansion joints are incorrectly set.

It is not just simply a bit of sun expanding rail and buckling it.
I'm surprised their wasn't heat related delays on the South West Trains mainline yesterday. The one through Earlsfield. I'd have expected them.

I know Worpolesden station has wooden sleepers going through it. I noticed them this year and was surprised to see them. I thought this line would all be concrete by now.
 
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