Laurencekirk GSJ

The study of British and Irish roads - their construction, numbering, history, mapping, past and future official roads proposals and general roads musings.

There is a separate forum for Street Furniture (traffic lights, street lights, road signs etc).

Registered users get access to other forums including discussions about other forms of transport, driving, fantasy roads and wishlists, and roads quizzes.

Moderator: Site Management Team

User avatar
Osthagen
Member
Posts: 3342
Joined: Sun Apr 19, 2015 15:01
Location: Mercia

Re: Laurencekirk GSJ

Post by Osthagen »

All of the options look fine. I think that option 2 would get my vote in this case.
"I see the face of a child. He lives in a great city. He is black. Or he is white. He is Mexican, Italian, Polish. None of that matters. What matters, he's an American child"
- Richard Nixon
User avatar
novaecosse
Member
Posts: 4722
Joined: Tue Nov 21, 2006 23:35
Location: Dundee, Scotland

Re: Laurencekirk GSJ

Post by novaecosse »

I'm surprised the Forties Pipeline System isn't shown as a Design Constraint, it's quite close to the A90 at Laurencekirk.
B9127
Member
Posts: 694
Joined: Wed Apr 02, 2008 20:45
Location: Angus Scotland

Re: Laurencekirk GSJ

Post by B9127 »

novaecosse wrote:I'm surprised the Forties Pipeline System isn't shown as a Design Constraint, it's quite close to the A90 at Laurencekirk.
By the time it is built the pipe will be empty
Motorways travelled 2019 - M90 - M9 - M80 - M8 -M77 - M73 -A74(M) -M6-M42-M40 -A404(M) - M4 - M5 -M50 -M56 much better so far than last year
Peter Freeman
Member
Posts: 1390
Joined: Thu Aug 30, 2012 07:52
Location: Exits 9 & 10, M1 East, Melbourne, Australia

Re: Laurencekirk GSJ

Post by Peter Freeman »

Option 2, with both sub-option A's. However, the bridge should be perpendicular not skewed, and the cloverleaf loops should be in the other two quadrants so that the link road can be nicely connected to the south roundabout (as it is in Option 1).
User avatar
Ruperts Trooper
Member
Posts: 12031
Joined: Sun Jun 17, 2012 13:43
Location: Huntingdonshire originally, but now Staffordshire

Re: Laurencekirk GSJ

Post by Ruperts Trooper »

I'm not in a position to give a detailed opinion of the options - but we sometimes stay with our caravan just north of Laurencekirk at Pitrennie Mill - the left turn from the south is easy but the right turn through the gap to go back south is difficult due to the amount of traffic with a caravan, even with a high-powered car - even worse for tractors.

With a GSJ south of Laurencekirk and the central gaps closed it'll be much safer to go south through the village itself - no point doing that now as it's still an at-grade turn through the gap.
Lifelong motorhead
User avatar
Bryn666
Elected Committee Member
Posts: 35755
Joined: Thu Jun 20, 2002 20:54
Contact:

Re: Laurencekirk GSJ

Post by Bryn666 »

Peter Freeman wrote:Option 2, with both sub-option A's. However, the bridge should be perpendicular not skewed, and the cloverleaf loops should be in the other two quadrants so that the link road can be nicely connected to the south roundabout (as it is in Option 1).
I'm not keen on Option 2 because of the extremely sharp turns the design provides. This seems needlessly substandard and landtake wise it doesn't appear to offer much, if any, saving over Option 1.
Bryn
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.

Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
Altnabreac
Member
Posts: 506
Joined: Wed Sep 30, 2015 11:50

Re: Laurencekirk GSJ

Post by Altnabreac »

Ideally you'd want to see Option 1 and the north junction from Option 3 built.

I suspect Option 3 wouldn't really work because the initial design work identified that a fair amount of the existing Laurencekirk bound traffic from Montrose already uses the B974 from Marykirk or the minor road to Drumnagair.

If you put a long diversion in at Laurencekirk you'll just encourage traffic to divert to those A90 gaps further south.

Shows the problem of just developing a strategy for individual junctions when really you need an overall Dundee - Stonehaven gap closure programme looking at the whole route.
Last edited by Altnabreac on Tue Oct 31, 2017 15:00, edited 1 time in total.
Peter Freeman
Member
Posts: 1390
Joined: Thu Aug 30, 2012 07:52
Location: Exits 9 & 10, M1 East, Melbourne, Australia

Re: Laurencekirk GSJ

Post by Peter Freeman »

Bryn666 wrote:
Peter Freeman wrote:Option 2, with both sub-option A's. However, the bridge should be perpendicular not skewed, and the cloverleaf loops should be in the other two quadrants so that the link road can be nicely connected to the south roundabout (as it is in Option 1).
I'm not keen on Option 2 because of the extremely sharp turns the design provides. This seems needlessly substandard and landtake wise it doesn't appear to offer much, if any, saving over Option 1.
Yes, the cloverleaf loops are fairly tight, but not, of course, as tight as the roundabout circulatory carriageways. Therefore traffic approaching the roundabout only needs to slow down a little earlier, and traffic leaving the roundabout must simply defer full acceleration.

I am very favourable to dumbbell roundabout junctions for limited access roads. Apart from their economy in structures (one bridge, versus two for a classic UK GSJ), they provide a useful way to service extra arms without traffic needlessly crossing and re-crossing the bridge(s). Either the diamond or partial cloverleaf shapes are OK for a dumbbell, but I marginally prefer the parclo as I believe it makes the roundabout work better. Its sequence of junctions as you circulate goes enter-exit-enter-exit-enter-exit, whereas the diamond form's sequence is enter-enter-exit-enter-exit-exit. It is easier to join the roundabout circulation if an exit lies immediately to your right, since exiting traffic creates a gap for you. Having no such gap-former can result in long streams of uninterrupted traffic coming off the bridge, making entry difficult or hazardous.
Nwallace
Member
Posts: 4239
Joined: Tue Apr 10, 2007 22:42
Location: Dundee

Re: Laurencekirk GSJ

Post by Nwallace »

How do the curves on the cloverleaf options compare to the curves and short acceleration lanes found elsewhere on the A90?

The Kirrie junction springs to mind as one where no sooner are you out the sharp corner than you're on the main line
B9127
Member
Posts: 694
Joined: Wed Apr 02, 2008 20:45
Location: Angus Scotland

Re: Laurencekirk GSJ

Post by B9127 »

Kirrie Junction is similar to the GSJ'S on the A92 between Monifieth and Arbroath all with very tight radii - one of the Laurencekirk options is similar to Muirdrum on the A92
Motorways travelled 2019 - M90 - M9 - M80 - M8 -M77 - M73 -A74(M) -M6-M42-M40 -A404(M) - M4 - M5 -M50 -M56 much better so far than last year
Nwallace
Member
Posts: 4239
Joined: Tue Apr 10, 2007 22:42
Location: Dundee

Re: Laurencekirk GSJ

Post by Nwallace »

B9127 wrote:Kirrie Junction is similar to the GSJ'S on the A92 between Monifieth and Arbroath all with very tight radii - one of the Laurencekirk options is similar to Muirdrum on the A92
Hm, that's one of the nicer junctions to use on that bit of the A92
User avatar
orudge
Site Manager
Posts: 8261
Joined: Sun May 27, 2007 12:23
Location: Banchory
Contact:

Re: Laurencekirk GSJ

Post by orudge »

Preferred option to be published on the 20th July, with public exhibitions to be held in Laurencekirk.

https://www.transport.gov.scot/news/a90 ... c-display/
User avatar
wrinkly
Member
Posts: 8986
Joined: Tue Mar 04, 2008 12:17
Location: Leeds

Re: Laurencekirk GSJ

Post by wrinkly »

Exhibition panels and leaflet now up

https://www.transport.gov.scot/projects ... t-details/
User avatar
novaecosse
Member
Posts: 4722
Joined: Tue Nov 21, 2006 23:35
Location: Dundee, Scotland

Re: Laurencekirk GSJ

Post by novaecosse »

wrinkly wrote: Fri Jul 20, 2018 18:44 Exhibition panels and leaflet now up

https://www.transport.gov.scot/projects ... t-details/
If they don’t close the centre gaps at the North and middle junctions, then the designers are idiots.
User avatar
jackal
Member
Posts: 7549
Joined: Tue Jan 08, 2008 23:33
Location: M6

Re: Laurencekirk GSJ

Post by jackal »

As they're proposing to retain the reservation gaps at the B9120 and A937 I have doubts about whether the scheme is really worth doing. Its quite a lot of money to get the job only a third done.
User avatar
Glen
Social Media Admin
Posts: 5426
Joined: Mon Mar 13, 2006 02:16
Location: Inbhir Pheofharain
Contact:

Re: Laurencekirk GSJ

Post by Glen »

It seems they are planning to leave the other two junctions open for the sake of not building an extra 1km of local access road to the B9120.
User avatar
Burns
Member
Posts: 3791
Joined: Mon Oct 16, 2006 21:37
Location: Dundee
Contact:

Re: Laurencekirk GSJ

Post by Burns »

A UK junction improvement scheme that's got a massive, glaring problem with it that any sane person can spot? That doesn't sound like the kind of thing that happens very often in this country... oh, wait. :wink:
User avatar
Bryn666
Elected Committee Member
Posts: 35755
Joined: Thu Jun 20, 2002 20:54
Contact:

Re: Laurencekirk GSJ

Post by Bryn666 »

Glen wrote: Sat Jul 21, 2018 16:20 It seems they are planning to leave the other two junctions open for the sake of not building an extra 1km of local access road to the B9120.
No doubt the (invariably rigged in favour of the client's cost cutting measures) traffic model says no one will use the gaps because of the safety benefits the GSJ provides.

Yeah I'm not convinced some highway design engineers actually understand human behaviour.
Bryn
Terminally cynical, unimpressed, and nearly Middle Age already.
She said life was like a motorway; dull, grey, and long.

Blog - https://showmeasign.online/
X - https://twitter.com/ShowMeASignBryn
YouTube - https://www.youtube.com/@BrynBuck
User avatar
Burns
Member
Posts: 3791
Joined: Mon Oct 16, 2006 21:37
Location: Dundee
Contact:

Re: Laurencekirk GSJ

Post by Burns »

Bryn666 wrote: Sat Jul 21, 2018 21:40
Glen wrote: Sat Jul 21, 2018 16:20 It seems they are planning to leave the other two junctions open for the sake of not building an extra 1km of local access road to the B9120.
No doubt the (invariably rigged in favour of the client's cost cutting measures) traffic model says no one will use the gaps because of the safety benefits the GSJ provides.

Yeah I'm not convinced some highway design engineers actually understand human behaviour.
It has the feel of the right angle triangle pathway problem. Designers put in a path around the edge of small, grassy area but no-one uses the path, instead, the third side of the triangle is completed by a muddy route along said grass.
David D Miller
Member
Posts: 636
Joined: Tue Jan 22, 2002 11:04
Location: St Andrews
Contact:

Re: Laurencekirk GSJ

Post by David D Miller »

From my experience, the problems on the A90 on the Laurencekirk by-pass are very much concentrated at the southern junction, and the limited improvements just published are no great surprise. Even before the 50 mph speed limit was imposed, I used to regularly slow below 60 mph through this junction, just as I used to at the similar flat junctions for Glamis and Kirriemuir down on the Forfar by-pass. The middle junction and northern junction at Laurencekirk simply aren't in the same league, are too important for local traffic to be closed off, and not enough of a problem to justify building two more expensive bridges.

On the Forfar by-pass, with its junctions originally built to the same standards as at Laurencekirk, only two of the four major junctions have been grade separated: The southern Forfar junction at Lochlands is effectively unchanged, just as the corresponding northern junction at Laurencekirk will be. The northern Forfar junction at Quilkoe has had its gap closed, with northbound traffic diverted via the nearby Kirriemuir junction.

There are still plenty of other flat crossings on the A90 between Dundee and Aberdeen. It's not a motorway.
Post Reply