Dublin Metrolink (just Metrolink posts here -see post #1 )

orangerhyme

donvito99 wrote: »

The attached link may be interesting to some, details the features of Barcelona's line 9, the single bore arrangement and its advantages particularly in terms of platform length and the relatively small footprint of stations compared with traditional methods.

http://www.cat-bus.com/2017/10/barcelonas-line-9-inspiring-montreals-pink-line/

That's really interesting, thanks.

7bn for 48km, so how much for 17km, considering Dublin would be less complex?
Maybe 2 to 3 bn

ricimaki

ted1 wrote: »

I would have thought they have electrified tracks

What's done in Barcelona, and could well be used here is a solid metal bar instead of a hanging catenary wire above the tracks. You can see it in this video

Another benefit to the 12m tunnel in Barcelona is that it allows quadruple track in some sections where the stations are built outside of the bore. It could allow express trains to skip some stops. Not really necessary for the relatively short route in Dublin, but could be useful elsewhere

donvito99

Does anyone know how resilient the trackbed on the existing Charlemont - Sandyford alignment is? i.e. how heavy a metro could be accommodated by it. Longer platforms is more easily done in single bore, so it would seem that the only factors stopping a much longer/heavier train is the loading gauge and what the max. load bearing limit of the Green line is.

Sam Russell

donvito99 wrote: »

Does anyone know how resilient the trackbed on the existing Charlemont - Sandyford alignment is? i.e. how heavy a metro could be accommodated by it. Longer platforms is more easily done in single bore, so it would seem that the only factors stopping a much longer/heavier train is the loading gauge and what the max. load bearing limit of the Green line is.

Is it not the same bed as carried the old Harcourt Street line - that is heavy heavy locomotives?

Grandeeod

donvito99 wrote: »

Does anyone know how resilient the trackbed on the existing Charlemont - Sandyford alignment is? i.e. how heavy a metro could be accommodated by it. Longer platforms is more easily done in single bore, so it would seem that the only factors stopping a much longer/heavier train is the loading gauge and what the max. load bearing limit of the Green line is.

I would be stunned if it couldn't carry a heavier load as it used to be a real railway.:D

Sam Russell

Perhaps the Dundrum Viaduct might be a worry but I doubt it.

bk

One issue with the above Barcelona tunnel is that it requires far more spoil (earth and rock) to be removed then a traditional tunnel, this greatly increases costs.

BTW You can put Metro trains side by side in a single tunnel bore. Plenty of examples of that and in fact the above Barcelona Metro line has many KM's of side by side trains in a single tunnel. They are only using the top/bottom approach in the core city center and more traditional methods in the Suburbs.

marno21

If the Charlemont-Sandyford section was built with Metro in mind I'd be very very surprised if the Dundrum bridge couldn't handle Metros

cgcsb

orangerhyme wrote: »

yeah but theyre be a metro station a few hundred meters either side.

Its just the Luas from OCS to STG causes so much hassle for 1km of track that will have a Metro covering the same route.

Im just thinking about once the metro is built in 10 years to be optimistic, even with the best of intentions as regards improving public transport, that part of the city center will still be vital for cars and buses, and the Luas will still be a pain in the hole crossing OCB and college green.

There won't be any cars in that part of the City 10 months from now, never mind 10 years form now.

Sam Russell

bk wrote: »

One issue with the above Barcelona tunnel is that it requires far more spoil (earth and rock) to be removed then a traditional tunnel, this greatly increases costs.

BTW You can put Metro trains side by side in a single tunnel bore. Plenty of examples of that and in fact the above Barcelona Metro line has many KM's of side by side trains in a single tunnel. They are only using the top/bottom approach in the core city center and more traditional methods in the Suburbs.

The Barca tunnel is 44 km underground while the Dublin tunnel is - what - 8 km.

The twin tunnel will also produce spoil, but more at the stations, because the Barca design has the station within the tunnel. So not a big problem. If the single tunnel works, the reduced cost might be worth it.

The Port tunnel was built in two years so the Mtrolink tunnel could be less than that.

Be great when they start.

marno21

Sam Russell wrote: »

The Barca tunnel is 44 km underground while the Dublin tunnel is - what - 8 km.

The twin tunnel will also produce spoil, but more at the stations, because the Barca design has the station within the tunnel. So not a big problem. If the single tunnel works, the reduced cost might be worth it.

The Port tunnel was built in two years so the Mtrolink tunnel could be less than that.

Be great when they start.

Metrolink tunnel is proposed to be 13km in length.

Sam Russell

marno21 wrote: »

Metrolink tunnel is proposed to be 13km in length.

That is the Airport to SSG so must be a curvy route. It is still a third of the Barca tunnel. The Port Tunnel was 5.7 km by two. Cost €1 bn iirc.

bk

Sam Russell wrote: »

That is the Airport to SSG so must be a curvy route. It is still a third of the Barca tunnel. The Port Tunnel was 5.7 km by two. Cost €1 bn iirc.

The full length of the Barcelona Tunnel isn't this over/under design, only the core city center section is, the outer sections are side by side in a single bore. The fact that they have two different approaches in this manner, makes me think the over/under design is a lot more expensive and only used because of lack of space in the city center.

It sort of makes sense, think about it, they probably have to put a massive amounts of effort into making sure that the floor between the levels will be able to take a heavy Metro, every 2 minutes, 24/7 for the next 100 years!

A wall separating two lines in a single bore by comparison should be a lot easier/cheaper.

It is a very cool design, but I suspect more complicated then we need. It looks like each of our planned stop locations has space for a regular station box. Certainly OCS and SSG E both have plenty of space for it, being wide streets. Only Tara looks a bit tight.

I suspect we will either go with single bore side by side or dual bore, both with regular station boxes.

Sam Russell

The single bore, side by side arrangement means a lot of the spoil can go back in to form the base below the track bed. The up-down arrangement means that stations are on the one side and within the tunnel - neat.

Maybe the Barca crew will try and get the tender.

ricimaki

Having a look at the planning applications map in Dublin, I found this right beside Tara. This is the building.

I couldn't see any other items relating to Metro North

salmocab

Lots of talk here about single bore or twin bore, surely a single bore with trains stacked would mean one much bigger tunnel as a tunnel that’s twice the height needed means 4 times the volume taken out so allowing for 2 tunnels that means twice the amount really. Also in the port tunnel there are a few places where you can switch tunnels in an emergency so I would assume that’s a factor too.

Sam Russell

salmocab wrote: »

Lots of talk here about single bore or twin bore, surely a single bore with trains stacked would mean one much bigger tunnel as a tunnel that’s twice the height needed means 4 times the volume taken out so allowing for 2 tunnels that means twice the amount really. Also in the port tunnel there are a few places where you can switch tunnels in an emergency so I would assume that’s a factor too.

Read about it here.

One 12 metre tunnel vs two 8 metre tunnels. Cross section = 113 sq metres vs 100 sq metres - not such a difference. One TBM instead of two - saving there. Safety is thought of and good solutions put forward.

I'd go with the Barca solution.

bk

So in Barcelona you have:

- Single Bore, lines side by side, 9m
- Single Bore, lines stacked, 12m

London Underground:
- Twin bore, 4.5m per tunnel.

I don't think you would go with stacked unless you have space issues with the station boxes, which I just don't think we have.

cgcsb

Shurimgreat wrote: »

New York, London, Paris are multi-dimensional lines.
LUAS/Metro North is a SINGLE Line. That means EVERYONE gets off at the one stop.

what does the above even mean?

Shurimgreat wrote: »

Then there is the question of space. LUAS lines will have to do a "U Turn" at Sandyford as will Metros. So two separate turning points for both. Plus platforms both ways for both. Meaning 4 platforms.

Underground works because you can put platforms and even lines at different heights. When you attempt transit stations above ground like that proposed at Sandyford you run into a myriad of problems.

As for magical fantasy land, its you who are living in it. Much like the average Dublin planner, you really haven't thought the whole thing through, the little details such as how Sandyford would work.

I despair at planners in this country. They take simple problems and turn them into the mother of all problems with the average commuter suffering.

trams don't do u turns. They have a drivers cab at both ends, the driver just gets in the other end and goes the other way.

cgcsb

Shurimgreat wrote: »

So they will be tearing up the Green Luas line extension to the Northside they spent hundreds of millions on in recent years?
What a complete waste of money so.

I think we can all agree the whole thing is an absolute shambles.

have you read this thread? that is the opposite of what is proposed.

cgcsb

Shurimgreat wrote: »

There are other stops and you know it. Broombridge, Cabra, Phibsborough, Grangegorman, Broadstone, and possibly Parnel as well as the 3 I mentioned.

Commuters from south of Sandyford to these locations will need 3 trams, a bit of walking as well as waiting/queuing for all 3 trams. A miserable commuting experience I would say.

2 trams, one change will be needed as has been explained here multiple times, change at Charlemont for the south side stops(if you really need to, but most likely you wont because all south side luas stops will be spitting distance from a metro station) and change at O'Connell For the northside, infact you'd get to the northside quicker than the current luas service.

no.8

Idbatterim wrote: »

thats true about the luggage, if they was an underground pedestrian tunnel with travelator , it might be ok, but without it, on surface! forget it!

I wonder roughly what the cost for each 90m below ground station will be (I am strongly assuming they are going with 90m)

Only 90m! That really doesn't leave much room for expansion does it

cgcsb

Consonata wrote: »

That map is crying out for Metro West. Its disappointing to see that its been left to the dust since that was one of the more promising projects for Dublin in my opinion. That and Metro North. The massive gap at Harolds cross really isn't acceptable, and isn't likely to be serviced till 2060 at this rate.

Indeed a densely populated wedge of the City around Harold's X gets nothing as of yet and little or no scope for better bus services. I expect Bus Connects will do something for the area, a few gardens CPOed and more bus lanes put in. Also there is a massive gap between the metro line and the northern DART line. I wouldn't worry though, once the travelling public have high frequency DARTs and metros criss-crossing the City the cries for an Artane-Harold's X metro line will be so deafening not even the dimmist of politician will ignore it. We may even see the Finglas-Charlemont line extended to UCD in time.

bk

no.8 wrote: »

Only 90m! That really doesn't leave much room for expansion does it

Well just 5 years ago they were proposing just 60m trains in order to save costs!

So most of us are hoping we are back to the original 90m.

90m is pretty standard for most big Metros, for instance I think most trains in Barcelona are 86m.

London Underground ranges from 66m up to 133m, but the average is around 110m, but then we have nothing like the population of London. 90m is probably a good length for us.

Yes, DART's are much longer, but Metro makes up with it with high frequency. A 90m Metro every 2 minutes is going to give you far more capacity then a 180m DART every 20 minutes or even 10 minutes. Plus people tend to prefer such high frequency, less time waiting at the station normally.

LXFlyer

cgcsb wrote: »

Indeed a densely populated wedge of the City around Harold's X gets nothing as of yet and little or no scope for better bus services. I expect Bus Connects will do something for the area, a few gardens CPOed and more bus lanes put in. Also there is a massive gap between the metro line and the northern DART line. I wouldn't worry though, once the travelling public have high frequency DARTs and metros criss-crossing the City the cries for an Artane-Harold's X metro line will be so deafening not even the dimmist of politician will ignore it. We may even see the Finglas-Charlemont line extended to UCD in time.

It will take a bit more than CPOing a few gardens - the Templeogue and Rathfarnham QBCs have the slowest average bus speeds in the city and without demolishing the various villages en route and massive CPO activity and, importantly, active enforcement of the priority measures, then not much will change. I remain to be convinced that the plans under BusConnects will see the light of day once the householders along the various corridors realise what’s involved - especially if a general election starts looming on the horizon.

It will only be solved by a long underground metro line that serves the Harold’s X, Terenure, Rathfarnham, Templeogue and Knocklyon areas, probably surfacing beyond Templeogue and ending in Tallaght but that’s something that our politicians probably don’t want to hear.

cgcsb

LXFlyer wrote: »

It will take a bit more than CPOing a few gardens - the Templeogue and Rathfarnham QBCs have the slowest average bus speeds in the city and without demolishing the various villages en route and massive CPO activity and, importantly, active enforcement of the priority measures, then not much will change.

It will only be solved by a long underground metro, something that our politicians probably don’t want to hear.

indeed but I expect there will be some measures brought in to improve buses in the area, but all tinkering around the edges stuff. Metro is needed. I expect that bus connects will include camera enforcements at key locations.

LXFlyer

cgcsb wrote: »

indeed but I expect there will be some measures brought in to improve buses in the area, but all tinkering around the edges stuff. Metro is needed. I expect that bus connects will include camera enforcements at key locations.

Quite - as you say all it will be is tinkering.

That whole area has some of the busiest bus routes in the city with little or no effectove priority in both directions (9, 14, 15 group, 16).

Sam Russell

LXFlyer wrote: »

Quite - as you say all it will be is tinkering.

That whole area has some of the busiest bus routes in the city with little or no effectove priority in both directions (9, 14, 15 group, 16).

What is needed is in-bus cameras that are sufficient for AGS prosecutions for errant motorists. Driver presses button, image goes to AGS, fixed penalty in the post, job done.

Also, traffic lights should always favour buses, if possible.

LXFlyer

Sam Russell wrote: »

What is needed is in-bus cameras that are sufficient for AGS prosecutions for errant motorists. Driver presses button, image goes to AGS, fixed penalty in the post, job done.

Also, traffic lights should always favour buses, if possible.

I think a bus driver should be focussing on driving his bus safely rather than pressing a button to take photos. Let’s be realistic about this. Any cameras have to be part of an automated process and not be a distraction from the bus driver driving safely.

The fundamental problem is the lack of roadspace and the large number of pinch points along the route.

tom1ie

Sam Russell wrote: »

What is needed is in-bus cameras that are sufficient for AGS prosecutions for errant motorists. Driver presses button, image goes to AGS, fixed penalty in the post, job done.

Also, traffic lights should always favour buses, if possible.

I posted a question about this before on boards, but I never got an answer, do dB busses have transponders fitted to give them priority at traffic lights?
I realize this creates its own problems in cc but in suburbia it would work well.
Surely it wouldn’t cost too much to get this infrastructure retrofitted to busses and traffic lights?