My interchange designs.

nordydan

This is an awful load of bollocks of a drawing, but what about a design similar to this? It keeps the M8 and M/N25 continuous, as that's what they're supposed to be

mysterious

nordydan wrote: »

This is an awful load of bollocks of a drawing, but what about a design similar to this? It keeps the M8 and M/N25 continuous, as that's what they're supposed to be

I would prefer that design myself.

I made my designs on whats currently acheievable.


You would have to removed the whole interchange and start from scratch. You have quite alot of bridges there. It would be a lot of work.

I think its good though. I would prefer the N25 mainline.

Chris_533976

Tunnel north to N25 east should be the mainline.

I drew a version of this myself a few years ago that had all movements resonably easily, including the stupid Little Island road. Unfortunately its easy to do if you have one set of traffic lights.

I reckon they'll have to put in a parallel road from the little island road on the south of Dunkettle to a massively upgraded Little Island junction, upgrade Dunkettle and fix up the Glanmire interchange all at once.

The Word Is Bor

Vertical alignment from tunnel to N8/M8 would not be achievable.

mysterious

The Word Is Bor wrote: »

Vertical alignment from tunnel to N8/M8 would not be achievable.

How not?

Chris_533976

One problem is that if you GSJ Dunkettle, then the Glanmire junction is right on top of the slips. You can save that problem with some slip roads.

This may have some unnaturally tight slips, and upgrading the Little Island junction is a pain in the ass, but overall (I think) this has most movements that matter freeflow.

Anyone spot any I left out?

mysterious

Chris that would not work at all.

Far to many flyover all over the place that have no coherent direction whatsoever.

mysterious

I can count at least 15 flyovers on your drawing.

L1011

mysterious wrote: »

Chris that would not work at all.

Far to many flyover all over the place that have no coherent direction whatsoever.

It appears, however, to be physically possible unlike your one. There is not the space for the N8 to rise above the N25 and drop back in time for the Glanmire junction. If you intend to keep the existing N25 flyover you'd be looking at an incline that many vehicles couldn't even manage.

nordydan's one has a slip sitting directly on top of the railway line at one stage...

murphaph

The Word Is Bor wrote: »

Vertical alignment from tunnel to N8/M8 would not be achievable.

Agreed, but didn't want to be the one to break the bad news to mysterious. He's looking at a 20~30% gradient to the tunnel mouth. Imagine trucks climbing out of the tunnel to a 30% gradient!

nordydan

MYOB wrote: »

nordydan's one has a slip sitting directly on top of the railway line at one stage...

My drawing was done in about 10 secinds in fairness!

Overheal

mysterious wrote: »

Here is a Map of existing Dunkettle








Here is my first one. The N25 free flow layout.


This is the best I can do With MS paint.:) If I had better tools it would be much easier.

• 3 extra bridges
• And Mainline N25 widened to facilitate merging movements.
• All movements are free flow.
• Existing roundabouts underpasses used
• Inexpensive and efficient layout.

These are not professional drawings. I cannot work out the exact measurement and aspect to scale using the tools that I have.

Now you're thinking American.

A good place to study would be Los Angeles.

mysterious

Noooo Overheal.


I'm thinking common sense. To be honest I find what you said insulting.

Sponge Bob

Overheal wrote: »

Now you're thinking American.

No he ain't , an American would build another tunnel under the tunnel coming out and merging near Glanmire

mysterious

Sponge Bob wrote: »

No he ain't , an American would build another tunnel under the tunnel coming out and merging near Glanmire

Overheal I'm glad I don't think like America and I'm sure glad I don't think like anyone else. I'm glad that I think for myself.

I was going to say something else about Overheal's comment.

But I'll bite my lip.

Road-Hog

No disrespect to mysterious etc but without having any vertrical and horizontal information on the existing alignment and a topographic survey of the adjacent lands its almost pointless doodling with MS paint etc using aerial photographaphy only, from my limited knowledge of road/interchange design there are all sorts of min, max and transition curves in the horizontal, hog and sag curves in the vertical and also max and min gradients and superelevations to take into account and not to mention potential archaeological, CPO, ecology and environmental issues. unfortunately all these issue too often can turn relatively straight forward looking upgrades majorily complicated projects. It would be interesting however to get some information on the proposals if any that there are from NRA or whoever they have farmed out this work to?

Irjudge1

mysterious wrote: »

Here is a Map of existing Dunkettle








Here is my first one. The N25 free flow layout.


This is the best I can do With MS paint.:) If I had better tools it would be much easier.

• 3 extra bridges
• And Mainline N25 widened to facilitate merging movements.
• All movements are free flow.
• Existing roundabouts underpasses used
• Inexpensive and efficient layout.

These are not professional drawings. I cannot work out the exact measurement and aspect to scale using the tools that I have.

I need some help here. For clarity I'm going to ignore the fact that orientation of the drawing is 180 Degrees out.

So if approachng from the West /Right and you wish to Head Northwards to the tunnel how do you get there? I cant see a connection onto the Northbound road. The road you are on simply travels under the North/South Dual C/W and leads you back to the road you came off?

mysterious

The Large Loop was there provided for it. Good spotting. I totally forgot to put that arrangement fully in.:o

I wil fix it.

Poster King

I'm loving this thread. Have done lots of this amateur junction layout stuff myself over the years.

The Naas Road - Long Mile Road junction is one junction that needs to be sorted out. see attached (I've not made an attempt to redesign yet)

I consider myself a competent and traffic aware driver, but still get nervous any time I approach this junction. Not long ago I witnessed 3 accidents (one quite serious and 2 minor) in the space of 2 minutes at this juntion on a fiday evening.
It is one of the craziest juntions. I simply can't believe that they did not put the Luas on a bridge.
(I'm sure there has been a thread on this before - if anyone could point me in the right direction it would be great)

nordydan

Poster King wrote: »

I'm loving this thread. Have done lots of this amateur junction layout stuff myself over the years.

The Naas Road - Long Mile Road junction is one junction that needs to be sorted out. see attached (I've not made an attempt to redesign yet)

I consider myself a competent and traffic aware driver, but still get nervous any time I approach this junction. Not long ago I witnessed 3 accidents (one quite serious and 2 minor) in the space of 2 minutes at this juntion on a fiday evening.
It is one of the craziest juntions. I simply can't believe that they did not put the Luas on a bridge.
(I'm sure there has been a thread on this before - if anyone could point me in the right direction it would be great)

I don't think this junction is upgradable in fariness, does the luas not need a very long incline and decline for its potential bridge?

sdanseo

nordydan wrote: »

I don't think this junction is upgradable in fariness, does the luas not need a very long incline and decline for its potential bridge?

Not really...look at the ramp in town at Peter Place. Very steep indeed - not a fan of it though :P

Zoney

I think you couldn't possibly manage to get the north/south mainline up and over the east/west, it would have to be the other way round. Due to the topography and the insane gradient you would have on the tunnel side (absolutely impractical - it would make the R526 overbridge on the SRR in Limerick look like the level!). I would imagine though that with the other way round, fitting in the slips would be more awkward.

While the arrangement of slip roads in mysterious's drawing may be somewhat attractive from above (in terms of not looking too incoherent or needing loads of bridges), that's about all that can be said.

Although I don't consider nordydan's effort that realistic either - his contribution that one should focus on making N25 and N8 continuous is interesting, but I wonder is it warranted? What are the busiest traffic flows on the junction? They are the ones that should probably be accommodated most rather than a theoretical N8/N25 continuity OR the North/South continuity.

I'm not suggesting doodling junction layouts is completely worthless - it is of some help in discussing them and dredging up the various issues that would be involved in a junction redesign. Plus it is presumably interesting too for those drawing them!

sdanseo

Irjudge1 wrote: »

I need some help here. For clarity I'm going to ignore the fact that orientation of the drawing is 180 Degrees out.

What does that matter? The before and after are both orientated the same, that's all that matters. He's not expected to be an architect.

Road-Hog

sdonn wrote: »

What does that matter? The before and after are both orientated the same, that's all that matters. He's not expected to be an architect.

North should always 'point up' as in go from bottown of page to top of page in the majority of plan type drawings.

Road-Hog

Road-Hog wrote: »

North should always 'point up' as in go from bottown of page to top of page in the majority of plan type drawings.

For the purpose of these drawings I don't think it really matters as long as the destinations are marked.

nordydan

There are some on this forum that seem to think you shouldn't even attempt to suggest a junction redesign without being a chartered civil engineer and producing a 300 page EIS yourself.

I'd rather see somebody suggest an alternative design, even if its unviable, rather that sit and snipe from the sidelines (often with a clear lack of ideas from their own). These drawings are done on MS Paint ffs, no-one is epxecting the Nobel prize for engineering. Fair play to anyone who at least gave it a lash. I spent a good 10 seconds on my effort. Ever tried designing a junction with a mouse and SM paint?? That's why God invented AutoCAD.:cool:

By the way the N25 north (through the JLT) to N8 west may be the biggest movement now from that direction, but if the Cork NRR is built a lot of traffic may head up the N8 to use this, so maybe existings orientations are correct. Just a thought;)

Sponge Bob

nordydan wrote: »

If the Cork NRR is built a lot of traffic may head up the N8 to use this, so maybe existings orientations are correct. Just a thought;)

Compensated for by southbound traffic from Fermoy that no longer uses Dunkettle. The NRR will end at the N20 though .....not around Ballincollig as I now understand it .

murphaph

nordydan wrote: »

There are some on this forum that seem to think you shouldn't even attempt to suggest a junction redesign without being a chartered civil engineer and producing a 300 page EIS yourself.

I'd rather see somebody suggest an alternative design, even if its unviable, rather that sit and snipe from the sidelines (often with a clear lack of ideas from their own). These drawings are done on MS Paint ffs, no-one is epxecting the Nobel prize for engineering. Fair play to anyone who at least gave it a lash. I spent a good 10 seconds on my effort. Ever tried designing a junction with a mouse and SM paint?? That's why God invented AutoCAD.:cool:

By the way the N25 north (through the JLT) to N8 west may be the biggest movement now from that direction, but if the Cork NRR is built a lot of traffic may head up the N8 to use this, so maybe existings orientations are correct. Just a thought;)

From my own perspective the only problem I have is the OP's virulent attacks on unknown engineers (and anyone who suggests the engneers had issues to deal with) for dealing with unknown geological problems on an unknown budget in an unknown way. The OP simply shouldn't be lambasting people when he has NONE of the facts to hand. Doodling away is fine and good fun, but coupled with the "I can do it so why can't the NRA engineers?" line it's something more and a little tiresome (and childish) when every single post from the OP is phrased like this.

nordydan

Sponge Bob wrote: »

Compensated for by southbound traffic from Fermoy that no longer uses Dunkettle. The NRR will end at the N20 though .....not around Ballincollig as I now understand it .

Here's the rest of it:

http://www.corkrdo.ie/files/CNRR%20Brochure-Preferred%20Route%20Part%201.pdf

mysterious

murphaph wrote: »

From my own perspective the only problem I have is the OP's virulent attacks on unknown engineers (and anyone who suggests the engneers had issues to deal with) for dealing with unknown geological problems on an unknown budget in an unknown way. The OP simply shouldn't be lambasting people when he has NONE of the facts to hand. Doodling away is fine and good fun, but coupled with the "I can do it so why can't the NRA engineers?" line it's something more and a little tiresome (and childish) when every single post from the OP is phrased like this.

lol. Somebody is envious, no surprise there.


But to debunk your nonsense and your petty dig. I don't think "I can and only do it". - "I don't think I'm better". " I also said my designs are not perfect. I can take constructive criticism, you murpaph as always show to have a little understanding of the actual skill I have in this subject. I would even say you would miss this in a lot of people.


I have been away from this thread for a while. I'm constantly drawing new designs of interchanges. I never said I was better than anyone else. I didn't look for compliments. I'm just doing it.


I am someone who is putting my ideas and work out there. I couldn't give a blimey what you think.


Something you have issues with. As your posts clearly states. Nobody is lambasting people only you. I stil think the NRA are goons. I won't deny that nor would else dissagree with me on that.