All Lane Running - Smart Motorways ?

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JohnnyMo
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All Lane Running - Smart Motorways ?

Post by JohnnyMo »

Driving down the M6 last weekend I noticed a number of upgrades in progress. Some were to All lane running other to 'Smart' motorway.

I think it would be better if a single style had been chosen, but are there and design/planning/... restrictions on which is the preferred solution.
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Re: All Lane Running - Smart Motorways ?

Post by Johnathan404 »

ALR is a type of Smart Motorway; the most extreme form with supposedly the most benefits.
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Re: All Lane Running - Smart Motorways ?

Post by wrinkly »

As discussed in other threads the trend seems to be towards ALR.

Are there any SM schemes currently under construction that aren't ALR?
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Re: All Lane Running - Smart Motorways ?

Post by DB617 »

I would hope that ALR is now the default for any sensible motorway conversion to 'Smart' being planned. The only places that anything else should be considered (on the mainline, slip roads and intersection arms being an entirely different situation) are where continuous D4ALR is not possible because of engineering issues like the M1 Tinsley Viaduct etc. Dynamic hard shoulder running like on the M42 J3a-J8 and M4/M5 interchange, in just about everyone's experience, has a net negative or near zero effect on traffic flow because it's just too difficult to control or drive correctly and safely. It was something of a bodge.

As an aside, is it being considered to convert any D2M to D3ALR or are there any examples where this has been used? I'm thinking M42 J9-A42, where I as a greenhorn driver discovered elephant racing, although the exchange with the M6 Toll and M6 might be an issue there.
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Re: All Lane Running - Smart Motorways ?

Post by JohnnyMo »

wrinkly wrote: Mon Sep 03, 2018 16:48 As discussed in other threads the trend seems to be towards ALR.

Are there any SM schemes currently under construction that aren't ALR?
I may have mis-understood the signage -- As some of the upgrades explicitly referred to all lane running and other upgrade just to smart motorway. Which I took as 3 lanes some of the time.
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Re: All Lane Running - Smart Motorways ?

Post by Ruperts Trooper »

DB617 wrote: Mon Sep 03, 2018 16:56 I would hope that ALR is now the default for any sensible motorway conversion to 'Smart' being planned. The only places that anything else should be considered (on the mainline, slip roads and intersection arms being an entirely different situation) are where continuous D4ALR is not possible because of engineering issues like the M1 Tinsley Viaduct etc. Dynamic hard shoulder running like on the M42 J3a-J8 and M4/M5 interchange, in just about everyone's experience, has a net negative or near zero effect on traffic flow because it's just too difficult to control or drive correctly and safely. It was something of a bodge.

As an aside, is it being considered to convert any D2M to D3ALR or are there any examples where this has been used? I'm thinking M42 J9-A42, where I as a greenhorn driver discovered elephant racing, although the exchange with the M6 Toll and M6 might be an issue there.
And yet the original M42 trial showed significant increase in average speeds - but I too would like to see D3ALR on M42, it would be nice to convert the A42 as well.
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Re: All Lane Running - Smart Motorways ?

Post by DB617 »

Ruperts Trooper wrote: Mon Sep 03, 2018 17:20

And yet the original M42 trial showed significant increase in average speeds - but I too would like to see D3ALR on M42, it would be nice to convert the A42 as well.
True, I'm probably being unfair on Managed Motorway; it has tangible gains for a motorway up to a certain congestion level. After this level it totally breaks down as people cannot weave in and out of the intermittent inner lane safely with three lanes of solid, minimum or less separation traffic to the right. A lot of people, including myself, tend to stick to GPS 60mph (60 on the M42 at least appears to be compulsory during HSR) and consequently just occupy the passing lanes as the rest of the traffic flows at less than 60 and fights with the DHSR.

Conversely ALR represents a near permanent capacity increase and improvement in overtaking opportunities. The effect of the extra lane is most clear during elephant racing scenarios, comparing them between D3M and D4ALR. An extra overtaking lane for car traffic makes ALL the difference.

I'm sure SABRE has discussed all this at length and will do again. I suppose it's one of the more interesting ways we're trying to squeeze every drop of capacity out of our existing (and crucially paid for) network.
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Re: All Lane Running - Smart Motorways ?

Post by Ruperts Trooper »

DB617 wrote: Mon Sep 03, 2018 20:01 Conversely ALR represents a near permanent capacity increase and improvement in overtaking opportunities. The effect of the extra lane is most clear during elephant racing scenarios, comparing them between D3M and D4ALR. An extra overtaking lane for car traffic makes ALL the difference.
Outside peak periods, my observation is the opposite - too many car drivers sitting in lane three mean there's still only one "overtaking" lane.
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Re: All Lane Running - Smart Motorways ?

Post by Bendo »

Ruperts Trooper wrote: Mon Sep 03, 2018 20:15
DB617 wrote: Mon Sep 03, 2018 20:01 Conversely ALR represents a near permanent capacity increase and improvement in overtaking opportunities. The effect of the extra lane is most clear during elephant racing scenarios, comparing them between D3M and D4ALR. An extra overtaking lane for car traffic makes ALL the difference.
Outside peak periods, my observation is the opposite - too many car drivers sitting in lane three mean there's still only one "overtaking" lane.
Snap. Lane discipline is horrendous in ALR sections, often it is easier to pass on the inside, although whilst I'm generally happy to do that in L1 with a hard shoulder I won't do it in L1 of an ALR section with nowhere to go if a buffon does decide to move over without looking.
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Re: All Lane Running - Smart Motorways ?

Post by TimM3-A55 »

DB617 wrote: Mon Sep 03, 2018 16:56
As an aside, is it being considered to convert any D2M to D3ALR or are there any examples where this has been used? I'm thinking M42 J9-A42, where I as a greenhorn driver discovered elephant racing, although the exchange with the M6 Toll and M6 might be an issue there.
Part of the A1(M) near stevenage between J6&8 is D2M and getting a smart motorway upgrade. I think that is the only one. Many D2M sections are too old with narrow hard shoulders to allow HSR or ALR. That shouldn't apply to the M42, it's no where near that old, but I don't know for sure.
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Re: All Lane Running - Smart Motorways ?

Post by Ruperts Trooper »

TimM3-A55 wrote: Tue Sep 04, 2018 12:56
DB617 wrote: Mon Sep 03, 2018 16:56
As an aside, is it being considered to convert any D2M to D3ALR or are there any examples where this has been used? I'm thinking M42 J9-A42, where I as a greenhorn driver discovered elephant racing, although the exchange with the M6 Toll and M6 might be an issue there.
Part of the A1(M) near stevenage between J6&8 is D2M and getting a smart motorway upgrade. I think that is the only one. Many D2M sections are too old with narrow hard shoulders to allow HSR or ALR. That shouldn't apply to the M42, it's no where near that old, but I don't know for sure.
AFAIK the M42 has a full-width hard shoulder from Jct 9 to 11 but the A42 north of that doesn't
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Re: All Lane Running - Smart Motorways ?

Post by DB617 »

Ruperts Trooper wrote: Tue Sep 04, 2018 13:09
TimM3-A55 wrote: Tue Sep 04, 2018 12:56
DB617 wrote: Mon Sep 03, 2018 16:56
As an aside, is it being considered to convert any D2M to D3ALR or are there any examples where this has been used? I'm thinking M42 J9-A42, where I as a greenhorn driver discovered elephant racing, although the exchange with the M6 Toll and M6 might be an issue there.
Part of the A1(M) near stevenage between J6&8 is D2M and getting a smart motorway upgrade. I think that is the only one. Many D2M sections are too old with narrow hard shoulders to allow HSR or ALR. That shouldn't apply to the M42, it's no where near that old, but I don't know for sure.
AFAIK the M42 has a full-width hard shoulder from Jct 9 to 11 but the A42 north of that doesn't
Worse than that, it's believed that at the time as cash ran out the option for expansion to D2M or D3 north of Tamworth was prevented for strange political reasons ('Better the project be dead than us looking bad later' mentality) , and the overbridge pillars deliberately obstruct a third lane or hard shoulder from being added. The A42 is one of the worst examples of British designing to spite ourselves. This leaves that section requiring structure rebuilds to even add a third lane without the hard shoulders, thus no easy fix smartifying there.
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Re: All Lane Running - Smart Motorways ?

Post by Ruperts Trooper »

DB617 wrote: Tue Sep 04, 2018 13:31
Ruperts Trooper wrote: Tue Sep 04, 2018 13:09
TimM3-A55 wrote: Tue Sep 04, 2018 12:56

Part of the A1(M) near stevenage between J6&8 is D2M and getting a smart motorway upgrade. I think that is the only one. Many D2M sections are too old with narrow hard shoulders to allow HSR or ALR. That shouldn't apply to the M42, it's no where near that old, but I don't know for sure.
AFAIK the M42 has a full-width hard shoulder from Jct 9 to 11 but the A42 north of that doesn't
Worse than that, it's believed that at the time as cash ran out the option for expansion to D2M or D3 north of Tamworth was prevented for strange political reasons ('Better the project be dead than us looking bad later' mentality) , and the overbridge pillars deliberately obstruct a third lane or hard shoulder from being added. The A42 is one of the worst examples of British designing to spite ourselves. This leaves that section requiring structure rebuilds to even add a third lane without the hard shoulders, thus no easy fix smartifying there.
To add to the A42's issues, the road surface has subsided in many places, presumably because of the Leicestershire & South Derbyshire Coalfield underneath.
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Re: All Lane Running - Smart Motorways ?

Post by Isleworth1961 »

Bendo wrote: Tue Sep 04, 2018 10:27
Ruperts Trooper wrote: Mon Sep 03, 2018 20:15
DB617 wrote: Mon Sep 03, 2018 20:01 Conversely ALR represents a near permanent capacity increase and improvement in overtaking opportunities. The effect of the extra lane is most clear during elephant racing scenarios, comparing them between D3M and D4ALR. An extra overtaking lane for car traffic makes ALL the difference.
Outside peak periods, my observation is the opposite - too many car drivers sitting in lane three mean there's still only one "overtaking" lane.
Snap. Lane discipline is horrendous in ALR sections, often it is easier to pass on the inside, although whilst I'm generally happy to do that in L1 with a hard shoulder I won't do it in L1 of an ALR section with nowhere to go if a buffon does decide to move over without looking.
I was on the M1 heading north a few weeks ago, between the A42 and M18 - it was really strangely quiet, but there were idiots driving in lane 3 at about 60 for seemingly mile after mile with nothing anywhere near them. As it was so quiet I saw them way in the distance in front, caught up with them, then passed on the left of them in lane 1 at 70, and saw them disappear in my mirror, still sitting in lane 3!
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Re: All Lane Running - Smart Motorways ?

Post by ManomayLR »

Ruperts Trooper wrote: Mon Sep 03, 2018 17:20
DB617 wrote: Mon Sep 03, 2018 16:56 I would hope that ALR is now the default for any sensible motorway conversion to 'Smart' being planned. The only places that anything else should be considered (on the mainline, slip roads and intersection arms being an entirely different situation) are where continuous D4ALR is not possible because of engineering issues like the M1 Tinsley Viaduct etc. Dynamic hard shoulder running like on the M42 J3a-J8 and M4/M5 interchange, in just about everyone's experience, has a net negative or near zero effect on traffic flow because it's just too difficult to control or drive correctly and safely. It was something of a bodge.

As an aside, is it being considered to convert any D2M to D3ALR or are there any examples where this has been used? I'm thinking M42 J9-A42, where I as a greenhorn driver discovered elephant racing, although the exchange with the M6 Toll and M6 might be an issue there.
And yet the original M42 trial showed significant increase in average speeds - but I too would like to see D3ALR on M42, it would be nice to convert the A42 as well.
The A42 would become Expressway as it would still have MS4s and (proudly) the first "Variable speed limit" signs put up with a green background!
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Re: All Lane Running - Smart Motorways ?

Post by James »

EpicChef wrote: Tue Sep 04, 2018 16:49
The A42 would become Expressway as it would still have MS4s and (proudly) the first "Variable speed limit" signs put up with a green background!
Unless something has changed since last I saw expressways will have blue signs! It will be A42(M) and M42 sadly

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Re: All Lane Running - Smart Motorways ?

Post by Johnathan404 »

James wrote: Tue Sep 04, 2018 18:18
EpicChef wrote: Tue Sep 04, 2018 16:49
The A42 would become Expressway as it would still have MS4s and (proudly) the first "Variable speed limit" signs put up with a green background!
Unless something has changed since last I saw expressways will have blue signs! It will be A42(M) and M42 sadly

https://screenshots.firefox.com/iMFX9ga ... ice.gov.uk
...and “variable speed limits” is not a direction sign so it would proudly be the wrong colour on two counts.
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Re: All Lane Running - Smart Motorways ?

Post by darkcape »

wrinkly wrote: Mon Sep 03, 2018 16:48 As discussed in other threads the trend seems to be towards ALR.

Are there any SM schemes currently under construction that aren't ALR?
M1 J23a-J24 is remaining D4, as it had already been widened to D4 previously there was no room left under the Ashby Rd bridge, meaning it's have to be demolished. The new A6 bridge should've allowed this to happen but instead the old bridge is being retained so we remain at 4 lanes with intermittent hard shoulders. Didn't stop them doing full verge reconstruction though.
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Re: All Lane Running - Smart Motorways ?

Post by James »

darkcape wrote: Tue Sep 04, 2018 20:00
M1 J23a-J24 is remaining D4, as it had already been widened to D4 previously there was no room left under the Ashby Rd bridge, meaning it's have to be demolished. The new A6 bridge should've allowed this to happen but instead the old bridge is being retained so we remain at 4 lanes with intermittent hard shoulders. Didn't stop them doing full verge reconstruction though.
Thats a suprise. Watching the new bridge take shape I had always assumed the old one was going to go. I wander why they are keeping it? The new bridge seems to make it redundant.
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Re: All Lane Running - Smart Motorways ?

Post by Alderpoint »

James wrote: Tue Sep 04, 2018 20:57 Watching the new bridge take shape I had always assumed the old one was going to go. I wander why they are keeping it? The new bridge seems to make it redundant.
From https://www.slp-emg.com/c/community/faqs.php

"KB12 Is the old Ashby Road bridge over the M1 going to be demolished?
No, the old bridge will remain and be used as a pedestrian and cycle route.
"
Let it snow.
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