Bridge between Scotland and Ireland

[Clive Arthur]

On 11/02/2020 21:43, Steve Walker wrote: <snip?

It's not the track gauge which is 4" 8.5" standard gauge, it's the size and form factor of the rest of the vehicle.

[Steve Walker]

If WWIII breaks out, what makes them think that anywhere in Europe wouldn't be a target, with or without a nuclear base?

SteveW

[mcp]

The proposed Portpatrick-Larne route would need about 100 miles of motorway to reach the M74.

[Tim Streater]

So it's the loading gauge we're talking about.

[jon lopgel]

Unlikely that anyone who matters would waste any nukes on scotland if there were no Tridents there anymore.

[Steve Walker]

The loading gauge.

If we were running trains over a bridge between Scotland and NI, we could design them for the smallest loading gauge that they would ever need to pass through. However I am pretty sure that NI, like the rest of Ireland, uses 5'3" gauge, hence the need for gauge changing.

SteveW

[Roger Hayter]

The only (remaining) railway route from Cardiff to Aberystwyth is via Shrewsbury!

[Marland]

There is a similar gauge difference between the older railways of France and Spain with Spain like Ireland using a wider gauge.When they built the new high speed routes the Spanish chose to build them to the std gauge rather than their wider one so high speed trains can run across the border and have plans for a rolling programme to convert some older routes to std, some like ones that serve the port of Barcelona are already converted to mixed gauge. New concrete sleepers in Spain are cast and laid with holes to suit fastenings for both gauges so as time goes by a lot of preparation work will already be done. Ireland should a rail carrying Bridge ever reach it would probably do something similar at least to Dublin.

GH

[Marland]

You are mixing up two traffic flows, what is the Eurostar passenger service was intended to have services going North from london that never took place Those trains were built to fit the smaller British loading gauge so they could do so and reach the original Waterloo Terminus. The high speed route to St Pancras now called HS1 can take continental sized trains. The vehicle Shuttles that run between the two terminals at each end of the tunnel are much larger than that even, the wagons are some of the largest in use anywhere.

To have built the line to take train wagons that size further inland would have been horrendously expensive and there would be no chance of practically rebuilding existing tracks to accommodate them. There was going to be a third style of train which were sleeper coaches to other parts of the UK to and from abroad overnight. The advent of Ryanair and Easy jet etc with their low fares from regional airports made the concept still born. After a while the fleet of brand new coaches that never turned a wheel in service were sold at little more than cost price to Canada where their small British size looks very odd amongst the normal stock over there.

GH

[Marland]

Used only with the special passenger stock, freight wagons go through the tedious bogie change. Now the new high speed std gauge lines in Spain are operational the gauge changers are disused.

GH

[Marland]

True but Ireland also a track gauge of 5ft 3? to complicate the issue, decided by Westminster in the 1800?s . Anxious to avoid the complications in Ireland that occurred here between the stephenson gauge of 4? 8.5? and Brunels 7? they dictated something in between. Not that it did any good, it proved too expensive to justify building in many places for the custom available so Ireland ended up with a secondary system of mainly isolated lines that were 3ft. Now long gone except for the 90 mile or so network that takes peat from the bogs to some power stations that burn it. The Irish Free state was anxious to stop its dependence on UK coal when it built them. They built some Hydro stations on rivers for the same reason.

GH

[polygonum_on_google]

True. Though I looked at a pre-grouping map the other day with the line up through Lampeter.

I wouldn't want the damage that would be caused to build one, but it would have been rather nice if there were a line from Cardigan to Aberwstwyth along the coast.

BBC news carries this headline today:

HS2: Outrageous rail project will not benefit Wales, transport expert says

[nightjar]

That only works on rolling stock, which has to pass through the gauge changer at about 10kph. Locomotives generally can't gauge change without changing the complete bogie and it is simpler to change the locomotive pulling the train instead. For passenger traffic, it would probably be cheaper to get the passengers to move themselves to a different train.

Which isn't really a problem, as you use trains that fit the smallest load gauge they are likely to meet. There are half a dozen different loading gauges in use on the UK mainland - seven if you include the Channel Tunnel rail link.

They chose the middle of the three different gauges in use in Ireland at the time - 4'8.5" 5'3" and 6'2".

Brunel's broad gauge was adopted because of the limitations of lubrication at the time. The wider gauge allowed the wheels to be placed outside the carriages, rather than under them. That allowed them to be larger and hence rotate more slowly at a given train speed.

[Roger Hayter]

An advantage for a re-instated line through Lampeter is that it would have very little competition from the roads. Not a great deal of traffic either, though.

[T i m]

<snip>

LOL!

Cheers, T i m

[nightjar]

...

You don't actually need to book in advance for the Channel Tunnel, except at the busiest times, and, even if you do book, you can usually turn up either early or late and get on the next available train.

As for cost, I wouldn't expect a road toll over such a bridge to be cheap. It would be built by a private concern that would want to get a return on the investment - just like the Channel Tunnel. OTOH, unlike a tunnel, a bridge could be built to carry both road and rail traffic. However, if the rail terminals were in sensible places, I would expect the speed and convenience of the rail link would prove to be more popular over time - just as the Channel Tunnel is preferred today over ferries by many regular travellers.

[newshound]

I'd never heard that before (slightly surprising being in the lubrication business). I had always assumed it was about capacity and stability. Here is one reference (sorry for the poor link)

Not mentioned in here

but some may be interested.

Also never realised before that Brunel's 7' gauge was actually tweaked upwards by a quarter of an inch.

[Andy Bennet]

I don't think the McCartneys would be amused.

[charles]

been on a train in Spain that had a track gauge change. The orginal loco uncoupled and went away. Carriages pushed onto gauge changer and coupled to a new loco on the other side. All very painless.

[Andrew May]

Been on the Trans-Siberian as it crosses from Russia into Mongolia. They lift the entire train in one go and change the bogies.

Didn't seem to mind passengers getting off before lifting the train and wandering around the bogie changing shed as they swung the bogies overhead.