Deforming railway tracks?!

[minimutly]

People forget that we have never had these temps in the UK

(Please don't start with '76, that was 10 degrees cooler)

The tracks were designed for a working temp plus a bit it margin, we are exceeding the margin

A river in Germany is drying up, complaining the massive barge can't transport coal down it. Cause and effect anyone?

Lack of rain obviously...
Actually, the bit about the German coal barge is quite clever.

 

[awemawson]

Lack of rain obviously...
Actually, the bit about the German coal barge is quite clever.

It just shows that the Earth is a self limiting system - too much heat, less rain, no rivers, no coal barge - sorted !

 

[Screwdriver]

It's actually only 3.5%. have a look at Kelvin temperatures for further details

Indeed and let's not forget, the rails (or any exposed item) are not simply being warmed up by the ambient air temperature, they are being heated directly by solar radiation.

Without getting into the "temperature" debate which is vastly complex for radiation, the temperature these rails can rise to is much higher than ambient air. The warm air just means the rails cannot dump excess heat so easily by convection.

 

[julianthegypsy]

I suppose with miles of continuous track even a small expansion per m of track adds up. And I suppose 35 degrees Vs 25 degrees is 40% hotter in percentage terms.
What do they do in places like Africa, India or Australia where it's always hot?

It's only a problem where the temperatures fluctuate. If it's always 32⁰ then there's no expansion or contraction. If the temperature drops to freezing over night then hits 30⁰ in the day, then you have a serious problem !

 

[bump]

Isn’t it about time they sorted this one out ? After all we have been told we are having more of this for the last 50 years.

Yeah but all those shareholders need to make sure that they take all the profits out first.

We should learn from the French and remove infrastructure planning, implementation and management from those that only have eyes on the next election. Then we might actually get somewhere.

 

[eLuSiVeMiTe]

Indeed and let's not forget, the rails (or any exposed item) are not simply being warmed up by the ambient air temperature, they are being heated directly by solar radiation.

Without getting into the "temperature" debate which is vastly complex for radiation, the temperature these rails can rise to is much higher than ambient air. The warm air just means the rails cannot dump excess heat so easily by convection.

65 degrees c was mentioned on the news today

 

[caprinut]

The expansion gaps in modern welded rails is scarf jointed, and the rails laid during mild weather so that when they are cooled in cold weather they are placed in tension in warm they are placed in compression the expansion joint at the end is take hot conditions however in extreme weather events can't be predicted or allowed for. There is a youtube video of conditions in Australia where this happens and a hapless driver coming round a corner to find that has happened the expletive and the result.

Bert

 

[mike os]

The expansion gaps in modern welded rails is scarf jointed, and the rails laid during mild weather so that when they are cooled in cold weather they are placed in tension in warm they are placed in compression the expansion joint at the end is take hot conditions however in extreme weather events can't be predicted or allowed for.

Bert

Unacceptable … everyone has been screaming about hotter summers for all my life, it’s plain incompetence

 

[mtt.tr]

Unacceptable … everyone has been screaming about hotter summers for all my life, it’s plain incompetence

Consider that the rails will also have to deal with minus c in the winter.

 

[mike os]

Consider that the rails will also have to deal with minus c in the winter.

And?

 

[mtt.tr]

And?

We talking metres of expansion and contraction

 

[mike os]

We talking metres of expansion and contraction

So compensate for it

 

[mike os]

Can’t wait for ss2 to be finished, some time next decade, with summer temperatures in the low 40’s and average travel times up 2 hours on todays with only 4 trains a day … yet everyone hailing it as a fantastic investment

 

[James1979]

So compensate for it

There was a chap from ‘the railway’ whoever that is, possibly Network Rail on Radio 4 earlier. He gave the most sensible, grown up explanation of this.

In a nutshell, what he said was
1, most of this infrastructure was planned and implemented 40 years ago to suit the climate then
2, European countries where there is warm summers and freezing winters can’t deal with it. They spend a fortune stressingrails in spring and de stressing them in autumn
3, HS2 is future proofed as its Slab Rail so the tracks run on a concrete road and there is no expansion instead of traditional ballast.

I am no expert. I found him interesting. He also was able to shoot down the stupid presenter woman who was trying to trip him up which was nice.

 

[mtt.tr]

So compensate for it

They do, the track is pre-tensioned

 

[mike os]

They do, the track is pre-tensioned

Inadequately

 

[mike os]

There was a chap from ‘the railway’ whoever that is, possibly Network Rail on Radio 4 earlier. He gave the most sensible, grown up explanation of this.

In a nutshell, what he said was
1, most of this infrastructure was planned and implemented 40 years ago to suit the climate then
2, European countries where there is warm summers and freezing winters can’t deal with it. They spend a fortune stressingrails in spring and de stressing them in autumn
3, HS2 is future proofed as its Slab Rail so the tracks run on a concrete road and there is no expansion instead of traditional ballast.

I am no expert. I found him interesting. He also was able to shoot down the stupid presenter woman who was trying to trip him up which was nice.

Just another excuse for not investing and improving … far too profit oriented

If my 40 year old car didn’t work would I continue driving it or fix it ?

 

[Wallace]

I remember going on an Italian train late 80's and how smooth it was, no constant clickety clack. Wasn't the welded rail introduced to give a better ride and less stress on the rolling stock?

 

[James1979]

Just another excuse for not investing and improving … far too profit oriented

If my 40 year old car didn’t work would I continue driving it or fix it ?

Chop it in for an EV on the latest grant scheme?

 

[mike os]

Chop it in for an EV on the latest grant scheme?

Been looking at it … I can’t afford it unless fuel nearly doubles