Potential 250km/h routes?

[popeter45]

what routes do you think could benifit from any kind of new 250-280Km/h lines rather than a full 360-400km/h High speed line?
one that sping to mind is a LGV Nord style Carlile-Glasgow-Edinburgh Line to replace the Scottish part of the WCML for HS2 trains, could also work well as a fast express line connecting Glasgow to Edinburgh avoiding all the slower stoping services between either of them on the current lines connecting them

 

[Noddy]

what routes do you think could benifit from any kind of new 250-280Km/h lines rather than a full 360-400km/h High speed line?
one that sping to mind is a LGV Nord style Carlile-Glasgow-Edinburgh Line to replace the Scottish part of the WCML for HS2 trains, could also work well as a fast express line connecting Glasgow to Edinburgh avoiding all the slower stoping services between either of them on the current lines connecting them

Why 250kmh? Unless you are specifically talking about linking cities close together (such as your Glasgow-Edinburgh example) why not go for the higher speed as the cost difference probably isn’t that different. I suppose Liverpool-Manchester or Manchester-Leeds might also be candidates but it depends on how those routes link and feed into northern sections HS2 (Phase 2 and hypothetical Phase 3 such as Leeds-Newcastle). Beyond those three examples I’m struggling see where would justify a brand new route specifically built to 250kph. If you were building a new route to Bristol and South Wales for example you might as well just go for the higher speed as the only stops on it would be Bristol, Newport (at a real push) and Cardiff. If you wanted to replicate the existing service I can’t see the point in building a new route?

 

[Irascible]

I'd be interested in figures actually - I too suspect it probably isn't much cheaper to build ( maybe less issues with alignment ) but the upkeep might be noticeably less, or maybe it isn't. London-Bristol-Exeter-Plymouth ( or London-Southampton-Exeter-Plymouth as an alternative ) perhaps, wouldn't save that much time as a faster line & the easier alignment might actually matter at the western end.

 

[cle]

Is the thinking around upping speeds on lines with more mixed traffic, or shorter stretches - like the ICE network has? Or the French bypass approach?

If so, I'd think Bristol Parkway - Birmingham and Birmingham - Derby might be good examples. MKC to Rugby and the central lines up the TV?

 

[The Planner]

Is the thinking around upping speeds on lines with more mixed traffic, or shorter stretches - like the ICE network has? Or the French bypass approach?

If so, I'd think Bristol Parkway - Birmingham and Birmingham - Derby might be good examples. MKC to Rugby and the central lines up the TV?

Good luck doing that at Weedon!

 

[Bald Rick]

The cost difference between 250km/h and 300km/h is essentially nothing, subject to significant topographical features. Pretty much the only change in standards is the strength of underbridges.

So why would you do it?

 

[popeter45]

The cost difference between 250km/h and 300km/h is essentially nothing, subject to significant topographical features. Pretty much the only change in standards is the strength of underbridges.

So why would you do it?

Ah i was under the impression the big cost jump was between 250-300 instead of 200-250 hence most high speed lines in Germany being 250-280 instead of 300-320

 

[Bald Rick]

Ah i was under the impression the big cost jump was between 250-300 instead of 200-250 hence most high speed lines in Germany being 250-280 instead of 300-320

I may be corrected here, but I think the Germany NBS lines (except Köln - Frankfurt) can also accommodate conventional traffic including high axle load freight. The French engineers wince uncontrollably if you suggest putting anything with an axle load over 17t on their LGVs.

 

[Irascible]

The cost difference between 250km/h and 300km/h is essentially nothing, subject to significant topographical features. Pretty much the only change in standards is the strength of underbridges.

So why would you do it?

Are there any significant differences in minimum radii? I'm thinking it may be a bit less costly if it's a particularily hilly area. No particular difference in maintenance costs? I guess that would depend mostly on what you run down it.

 

[Clansman]

It depends what is mean by 'benefit' in this question.

Of course, every route would benefit from 250km/h running in theory so long as the journey times are increased when taking into account accerleration time and stopping distances. To what extent they'd benefit in the confines of what is reasonable, is another question altogether. Let's say we remove economics (within reason) from the matter and focus only on effiency and journey time improvements. It is agreed somewhat that 125mph under the current infrastructure is the most efficient to operate at. Anything more would cost more, and result in mininimal improvements in journey times - with the potential to even create longer journey times if acceleration is poor and breaking requires greater distances.

If you were going by alignments, one could argue that in Scotland you could shave off around 5-15 mins in 250km+ running between Dunblane-Aberdeen (economics aside), and . And if you were going by true benefits, then look no further than what HS2 shaves off.

What truly suits 150km+ (155mph+) running isn't alignments, or high usage commuter belts in a 100 mile radius, but sheer non stop running distance alone. Plain and simple. If anyone needed an example, look at the journey time from Hong Kong to Beijing direct on a high speed train is on an average miles per hour basis. 8-9 hours on the train, 3 hours by plane, 1200 miles. That's the equivilant of a direct train from London to Tunisia roughly, in 8 bloody hours. The same journey time that gets you from London to Inverness (~500 miles) or there abouts. A journey that'd only be up to (at a guess) 30-45 minutes quicker if you were to fork out the investment to allow the speeding up running on the straighter sections under current stopping patterns.

Certainly makes one think, and puts the speed increase argument into perspective in a UK context.

 

[class26]

It depends what is mean by 'benefit' in this question.

Of course, every route would benefit from 250km/h running in theory so long as the journey times are increased when taking into account accerleration time and stopping distances. To what extent they'd benefit in the confines of what is reasonable, is another question altogether. Let's say we remove economics (within reason) from the matter and focus only on effiency and journey time improvements. It is agreed somewhat that 125mph under the current infrastructure is the most efficient to operate at. Anything more would cost more, and result in mininimal improvements in journey times - with the potential to even create longer journey times if acceleration is poor and breaking requires greater distances.

If you were going by alignments, one could argue that in Scotland you could shave off around 5-15 mins in 250km+ running between Dunblane-Aberdeen (economics aside), and . And if you were going by true benefits, then look no further than what HS2 shaves off.

What truly suits 150km+ (155mph+) running isn't alignments, or high usage commuter belts in a 100 mile radius, but sheer non stop running distance alone. Plain and simple. If anyone needed an example, look at the journey time from Hong Kong to Beijing direct on a high speed train is on an average miles per hour basis. 8-9 hours on the train, 3 hours by plane, 1200 miles. That's the equivilant of a direct train from London to Tunisia roughly, in 8 bloody hours. The same journey time that gets you from London to Inverness (~400 miles) or there abouts. A journey that'd only be up to (at a guess) 30-45 minutes quicker if you were to fork out the investment to allow the speeding up running on the straighter sections under current stopping patterns.

Certainly makes one think, and puts the speed increase argument into perspective in a UK context.

London - Inverness is well over 500 miles

 

[Clansman]

London - Inverness is well over 500 miles

Typo

 

[Bald Rick]

Are there any significant differences in minimum radii? I'm thinking it may be a bit less costly if it's a particularily hilly area. No particular difference in maintenance costs? I guess that would depend mostly on what you run down it.

Yes, clearly the higher the speed the higher the minimum radius. And yes it then does become a potential issue in areas of mildly challenging topography. In more challenging topography it doesn’t make much difference - you’re going over or under it regardless.

 

[Chris Butler]

Surely:-

1. the minimum radius (all other things being equal) depends on speed with the consequence that higher maximum speeds constrain the route to some degree (and not just because of topography since housing, protected land/monuments, rivers, bogland etc. etc. etc. also have to be avoided),
   
   
2. track maintenance costs increase very significantly with speed. I know that road maintenance/repair requirements are proportional to the third or fourth power of the speed of traffic, so I assume a very similar dependence applies for rail as well.

 

[Bald Rick]

Surely:-

1. the minimum radius (all other things being equal) depends on speed with the consequence that higher maximum speeds constrain the route to some degree (and not just because of topography since housing, protected land/monuments, rivers, bogland etc. etc. etc. also have to be avoided),
   
   
2. track maintenance costs increase very significantly with speed. I know that road maintenance/repair requirements are proportional to the third or fourth power of the speed of traffic, so I assume a very similar dependence applies for rail as well.

1) yes, but between 250 and 300, not that much.

2) yes they do, up to a point. Once above 125mph, there’s little difference, as it is all the highest standard for ballasted track, and speed has little effect on the rate of asset deterioration. If it’s slab (as HS2 will be) there’s no difference at all.

 

[DJ_K666]

As someone who doesn't 'Do' metric, what is 250km/h in miles?

 

[Philip Phlopp]

As someone who doesn't 'Do' metric, what is 250km/h in miles?

155mph

 

[DJ_K666]

155mph

Thanks

 

[Irascible]

Yes, clearly the higher the speed the higher the minimum radius. And yes it then does become a potential issue in areas of mildly challenging topography. In more challenging topography it doesn’t make much difference - you’re going over or under it regardless.

Which is what I was considering - at some point numbers get large enough that they're practically indistinguishable outside of edge cases. Having said that, 250kmh is not really much faster than our 200kmh rather-less-costly format & alignment wise probably isn't that far removed. Still not worth I feel it unless the cost of a proper high speed line is astronomically more ( I'd imagine Cornwall might have some challenges... ).

 

[JonasB]

I may be corrected here, but I think the Germany NBS lines (except Köln - Frankfurt) can also accommodate conventional traffic including high axle load freight. The French engineers wince uncontrollably if you suggest putting anything with an axle load over 17t on their LGVs.

That is probably part of the reason. Another reason is that Germany is a very polycentric country compared to France. So as the average journey is likely to be much shorter, 250 km/h might be enough for most trips.

 

[The Ham]

Surely:-

1. the minimum radius (all other things being equal) depends on speed with the consequence that higher maximum speeds constrain the route to some degree (and not just because of topography since housing, protected land/monuments, rivers, bogland etc. etc. etc. also have to be avoided),
   
   
2. track maintenance costs increase very significantly with speed. I know that road maintenance/repair requirements are proportional to the third or fourth power of the speed of traffic, so I assume a very similar dependence applies for rail as well.

When designing roads speed has no impact on the construction makeup of the road, it's all about volume of HGV's and other large vehicles.

Whilst that doesn't exclude the fact that maintenance costs are likely to be much higher in high speed roads. However it's be interesting to see the data for those higher maintenance costs for roads, as probably a lot of high speed roads with high volumes of traffic are constructed with concrete which is harder to maintain (read more costly).

 

[ABB125]

When designing roads speed has no impact on the construction makeup of the road, it's all about volume of HGV's and other large vehicles.

Whilst that doesn't exclude the fact that maintenance costs are likely to be much higher in high speed roads. However it's be interesting to see the data for those higher maintenance costs for roads, as probably a lot of high speed roads with high volumes of traffic are constructed with concrete which is harder to maintain (read more costly).

I was under the impression that concrete was cheaper, since it lasts longer than tarmac?

Apologies for digressing slightly

 

[The Ham]

I was under the impression that concrete was cheaper, since it lasts longer than tarmac?

Apologies for digressing slightly

Whilst it does last longer, when it does need replacing/repairing it's fairly expensive, not least that because of the time taken to replace it.

Asphalt Paving is fairly easy maintain, as other the surface course the rest of of the road doesn't need much/any work, unless the sub base fails (however that's then a major problem for concrete roads).

 

[Bald Rick]

Whilst it does last longer, when it does need replacing/repairing it's fairly expensive, not least that because of the time taken to replace it.

Same for slab track.

 

[ABB125]

Whilst it does last longer, when it does need replacing/repairing it's fairly expensive, not least that because of the time taken to replace it.

Asphalt Paving is fairly easy maintain, as other the surface course the rest of of the road doesn't need much/any work, unless the sub base fails (however that's then a major problem for concrete roads).

Ah right, thanks.

 

[Chris Butler]

When designing roads speed has no impact on the construction makeup of the road, it's all about volume of HGV's and other large vehicles.

Whilst that doesn't exclude the fact that maintenance costs are likely to be much higher in high speed roads. However it's be interesting to see the data for those higher maintenance costs for roads, as probably a lot of high speed roads with high volumes of traffic are constructed with concrete which is harder to maintain (read more costly).

I am talking about for the same road, or construction of road, how the costs of maintenance depend on speed with all other things being equal. Obviously, capital and construction methods (or parameters) are different depending on the (expected) traffic profile.