Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Well I suppose there are two theories about what ramp metering does:
1. Keeps flows smooth, giving better access onto the motorway from the onslip as well as a better motorway journey (mutual benefit model)
2. Prioritizes motorway traffic at the cost of worse onslip access (trade-off model)
Highways authorities like to emphasize the mutual benefit model, because it sounds nicer to say that everyone benefits rather than saying many gain, a few lose out. But the practice of turning off the metering when a queue is detected at the top of the slip suggests that the trade-off model is actually closer to the truth. After all, as WHBM says, if the mutual-benefit model was correct, turning off the metering would be self-defeating and would just make the slip queue even longer.
1. Keeps flows smooth, giving better access onto the motorway from the onslip as well as a better motorway journey (mutual benefit model)
2. Prioritizes motorway traffic at the cost of worse onslip access (trade-off model)
Highways authorities like to emphasize the mutual benefit model, because it sounds nicer to say that everyone benefits rather than saying many gain, a few lose out. But the practice of turning off the metering when a queue is detected at the top of the slip suggests that the trade-off model is actually closer to the truth. After all, as WHBM says, if the mutual-benefit model was correct, turning off the metering would be self-defeating and would just make the slip queue even longer.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
A piece on the BBC today: -
http://www.bbc.co.uk/news/uk-england-ma ... r-41967961
How can this possibly work ? And, more importantly, how can it be safe ? If you stop traffic joining the M62 from the M6, it will tailback onto the M6. The potential for rear-shunt accidents is immense. You only need a lorry tearing along at maximum to miss seeing the rear of the queue to result in a very serious accident with multiple fatalities. So what will happen now, is a speed limit will be applied over the whole of the junction. As there is already a temporary limit of 50 mph, this will be made permanent and create a huge bottleneck on the M6.
http://www.bbc.co.uk/news/uk-england-ma ... r-41967961
How can this possibly work ? And, more importantly, how can it be safe ? If you stop traffic joining the M62 from the M6, it will tailback onto the M6. The potential for rear-shunt accidents is immense. You only need a lorry tearing along at maximum to miss seeing the rear of the queue to result in a very serious accident with multiple fatalities. So what will happen now, is a speed limit will be applied over the whole of the junction. As there is already a temporary limit of 50 mph, this will be made permanent and create a huge bottleneck on the M6.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Firstly, the loop has an advisory 40 limit anyway, and a lorry wouldn't be doing enough to cause a 'very serious accident with multiple fatalities'. Given there are often queues on that slip road anyway, and no one has managed to do what you suggest, I think this risk is massively overstated. When it is quiet the signals will be off and there will be no problem.
As for making everything 50 because of some ramp metering, that's really rather tin foil hat stuff. No other ramp metering site has a permanent speed limit lower than 70, and the M62 itself will have variable speed limits on approach anyway.
As for making everything 50 because of some ramp metering, that's really rather tin foil hat stuff. No other ramp metering site has a permanent speed limit lower than 70, and the M62 itself will have variable speed limits on approach anyway.
Bryn
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Thanks for t hat. As I've never gone along the link, I didn't know about the 40mph advisory. I hear what you say about existing ramp metering, but surely this is the first Motorway-Motorway metering, all the others are for joining/leaving the motorway.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
The downside of this is that drivers do make an assumption, often quite reasonable, about what such a limit is for. This is an issue not only on roads but has arisen in railway accidents as well. So they may presume the limit is for curvature etc, when it is now also maintained for the chance of standing traffic ahead.Bryn666 wrote:Firstly, the loop has an advisory 40 limit anyway.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Isn't the sb->eb left turn also getting ramp metered? If it has an advisory at all it must be higher than 40.
I do think rear-ending is a risk, and the fact that it exists already from current queues is cold comfort. The objective should be to remove such hazardous speed differentials through increased mainline capacity rather than formalising them.
I do think rear-ending is a risk, and the fact that it exists already from current queues is cold comfort. The objective should be to remove such hazardous speed differentials through increased mainline capacity rather than formalising them.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
There will be massive signs warning of the signals, ultimately (as I say until I am blue in the face) it is the responsibility of the driver to drive to the conditions, if they can't see around the corner then they shouldn't be doing 80 into it.
My bigger concern is that it's taken HE nearly 12 months to do this work despite the fact it was billed to last less than 6 initially. What was the delay?
My bigger concern is that it's taken HE nearly 12 months to do this work despite the fact it was billed to last less than 6 initially. What was the delay?
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
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
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
I think your face will remain blue for a long time because charging round blind bends at speed must be the second-most dangerous practice of so many drivers on our roads today, tailgating being the first. Or maybe its the other way round !There will be massive signs warning of the signals, ultimately (as I say until I am blue in the face) it is the responsibility of the driver to drive to the conditions, if they can't see around the corner then they shouldn't be doing 80 into it.
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Perhaps the delay was due to designing a suitable sign that says "possible queues ahead" - for those motorists who cannot register seeing a "traffic-light" triangle with "SLOW" underneath? Or getting approval to hack down the undergrowth so that motorists can see THROUGH the bend and gain valuable yards of advance warning of stationary rear-ends? Miss the clearance slot ahead of the start of the nesting season and you're out by a year, old chap!Bryn666 wrote:There will be massive signs warning of the signals, ultimately (as I say until I am blue in the face) it is the responsibility of the driver to drive to the conditions, if they can't see around the corner then they shouldn't be doing 80 into it.
My bigger concern is that it's taken HE nearly 12 months to do this work despite the fact it was billed to last less than 6 initially. What was the delay?
Mike Hindson-Evans.
Never argue with a conspiracy theorist.
They will drag you down to their level and beat you with experience.
Never argue with a conspiracy theorist.
They will drag you down to their level and beat you with experience.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
How long until we start having traffic lights on the mainline, y’know, like signalised roundabouts?? Then the speed limit will need to be cut, of course...
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Berk wrote:How long until we start having traffic lights on the mainline, y’know, like signalised roundabouts?? Then the speed limit will need to be cut, of course...
A flat roundabout every few hundred metres allowing access to a housing estate or retail park probably :/
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Exactly this is planned for the M181.booshank wrote:Berk wrote:How long until we start having traffic lights on the mainline, y’know, like signalised roundabouts?? Then the speed limit will need to be cut, of course...
A flat roundabout every few hundred metres allowing access to a housing estate or retail park probably :/
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Reading the comments on that BBC article has really given me a headache. Here's a selection (apologies in advance for any blood-boiling that occurs):
And the signals are being installed where there is already stationary traffic in rush hour - if anything these signals are designed to reduce the risk of stationary traffic.
Hmm, not sure they're too familiar with this junction if they reckon it needs free-flow slips...Looks like a bigger better junction with dedicated free flowing and extended slip roads is required now- not in 20 years time( ala the now improved M1/M6/A14 Catthorpe or M25 junctions with the eastbound A2/M2 and M20)
Solid facts here coupled with the hint that traffic lights cause people to run red lights.Every single roundabout I know that has had traffic lights installed cause greater congestion and more incidents.
They also result in people running red lights in quiet periods
Everyone seems oblivious to the M18/A1M jct, Lofthouse, Simister, Thornham, M27/M271, which are instances of signals already on motorways - and to anyone with a brain realise that many other A-route interchanges with signals which people manage to negotiate safely every day.Traffic lights on a Motorway ?? a disaster waiting to happen .. come to a stop on a Motorway is risking your own death and everyone else's .. what moron thought this up ?
And the signals are being installed where there is already stationary traffic in rush hour - if anything these signals are designed to reduce the risk of stationary traffic.
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
That would need downgrading from motorway status first.jackal wrote:Exactly this is planned for the M181.booshank wrote:Berk wrote:How long until we start having traffic lights on the mainline, y’know, like signalised roundabouts?? Then the speed limit will need to be cut, of course...
A flat roundabout every few hundred metres allowing access to a housing estate or retail park probably :/
Formerly known as 'lortjw'
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
I (sincerely) fail to understand the thinking behind that. I have observed traffic for many years, long before I learned to drive. My experience shows that red lights simply allow queues to form -sure, they may allow opposing flows some opportunity to enter - but the tailbacks on the mainline are usually pronounced, and virtually never clear during rush hour.darkcape wrote:And the signals are being installed where there is already stationary traffic in rush hour - if anything these signals are designed to reduce the risk of stationary traffic.
My conclusion is that signals are only deployed to allow some equality of access to a junction, but not to improve traffic flow.
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Well, one roundabout at least.jackal wrote:Exactly this is planned for the M181.booshank wrote: A flat roundabout every few hundred metres allowing access to a housing estate or retail park probably :/
No doubt that will happen.lotrjw wrote:That would need downgrading from motorway status first.
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
Indeed! You definitely need to apply your 'marketing hype filter' to the promotional materials - even to the detailed, erudite and backed-up papers published here by VicRoads (= H.E.).jackal wrote: ... two theories about what ramp metering does ... (mutual benefit model) ... (trade-off model) ... the trade-off model is actually closer to the truth.
Our first, single-site implementation was initially publicised as "Easy-Merge". This went down well, and in fact it worked well and still does. Most of our (Australian) on-ramps begin at traffic signals not roundabouts, so we have a more intense 'platoon' effect. Breaking up these platoons of vehicles is definitely helpful.
As the system was expanded, especially when it included on-ramps that became lane-gains, the "Easy-Merge" label was dropped and the mutual benefit advantage was promoted. Even though most drivers broadly accept this notion, everyone sitting in the queue actually knows that it's also a trade-off.
I think that on top of this there is an aspect of 'demand management'. Some users (though only a small proportion) will avoid the queue by avoiding the freeway, ie. use a local-road route instead. This is especially the case for hop-on-hop-off users.
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
There are no roundabouts on this junction, it is a full free flow motorway to motorway junction, so it is in no way the same as the M18 to A1M, nor the M27/M271 junction. The 40mph advisory is exactly that, advisory. I fail to see how making already stationary or nearly stationary traffic stay stationary for longer will make things better. Perhaps just leaving it alone and let it work (albeit slowly) as it has done for decades may be the best option here. You can't fix everything. I can't see a single gain from this whatsoever and just a huge taxpayer bill for installation of the lights. It's fantastic how they have money for this and not to repaint and resurface the small section of A1(M) at Leeming Bar, which will probably produce a better benefit.
How about some more beans Mr. Taggart?
Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
What interests me here is that ramp metering was trialled in a number of places in the early 2000s as a way of relieving congestion - in the early days of SABRE I remember a discussion around Highways Agency trials on (I think) the M3 and M27 where the traffic signal heads were in the middle of huge blue diamond-shaped boards. And at that time, of course, the pedantic response was that actually we already had ramp metering, it had been in use on entrances to the M6 in the West Midlands for years. Ramp metering was then introduced to the M42 as a component of the original Active Traffic Management (proto-Smart Motorway) scheme.
The ramp metering on the M27 and M3 is, to my knowledge, gone now, as are the signals on the M6 in the West Midlands. I don't regularly use the M42, certainly not in the rush hour, but I'm not certain the ATM ramp metering system is in regular use any more either. I would conclude from this that the effect of ramp metering at a wide range of places was not satisfactory and the trials weren't considered successful. So how come, ten years later, we're installing ramp metering again (this time on a free-flowing motorway interchange, heaven help us) in the hope that it's going to make the M62 flow more smoothly? Is there something different about this ramp metering scheme or is it just that Highways England's institutional memory doesn't stretch back as far as mine does?
For full pedant points, I don't actually believe this is the first use of ramp metering at a motorway-to-motorway junction either. I'm almost certain the blue diamond experimental ramp metering lights of the early 2000s were trialled, among other places, at the M27/M271 interchange for traffic joining the M27.
Edit: here's some additional info from the SABRE archives. M27/M3 ramp metering was abandoned in 2005, so the trial must have only run for two or three years before HA gave up on it. Ramp metering has also been used at two other motorway-motorway junctions in the past: M4 J8/9 (OK, another roundabout interchange, but it's still a motorway-motorway junction), installed in 2008, and in the same year M25 J5 got them too for the clockwise entry from the A21.
The ramp metering on the M27 and M3 is, to my knowledge, gone now, as are the signals on the M6 in the West Midlands. I don't regularly use the M42, certainly not in the rush hour, but I'm not certain the ATM ramp metering system is in regular use any more either. I would conclude from this that the effect of ramp metering at a wide range of places was not satisfactory and the trials weren't considered successful. So how come, ten years later, we're installing ramp metering again (this time on a free-flowing motorway interchange, heaven help us) in the hope that it's going to make the M62 flow more smoothly? Is there something different about this ramp metering scheme or is it just that Highways England's institutional memory doesn't stretch back as far as mine does?
For full pedant points, I don't actually believe this is the first use of ramp metering at a motorway-to-motorway junction either. I'm almost certain the blue diamond experimental ramp metering lights of the early 2000s were trialled, among other places, at the M27/M271 interchange for traffic joining the M27.
Edit: here's some additional info from the SABRE archives. M27/M3 ramp metering was abandoned in 2005, so the trial must have only run for two or three years before HA gave up on it. Ramp metering has also been used at two other motorway-motorway junctions in the past: M4 J8/9 (OK, another roundabout interchange, but it's still a motorway-motorway junction), installed in 2008, and in the same year M25 J5 got them too for the clockwise entry from the A21.
Chris
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Re: Motorway to motorway (M2M) metering pilot scheme M62 junction 10 (Croft Interchange)
The signal heads on blue diamonds survived on the NB on-slip at M6 J10 until it was reconfigured as a smart motorway. Ironically, I never saw those signals in use, while the SB set, in the now-customary yellow oval, were often in operation. You are correct that the signals on the M6 are all now gone, while at least one set survives on M42 at my nearest junction, J3 for A435, where they control the EB on-slip on a part time basis.Chris5156 wrote:What interests me here is that ramp metering was trialled in a number of places in the early 2000s as a way of relieving congestion - in the early days of SABRE I remember a discussion around Highways Agency trials on (I think) the M3 and M27 where the traffic signal heads were in the middle of huge blue diamond-shaped boards. And at that time, of course, the pedantic response was that actually we already had ramp metering, it had been in use on entrances to the M6 in the West Midlands for years. Ramp metering was then introduced to the M42 as a component of the original Active Traffic Management (proto-Smart Motorway) scheme.
The ramp metering on the M27 and M3 is, to my knowledge, gone now, as are the signals on the M6 in the West Midlands. I don't regularly use the M42, certainly not in the rush hour, but I'm not certain the ATM ramp metering system is in regular use any more either. I would conclude from this that the effect of ramp metering at a wide range of places was not satisfactory and the trials weren't considered successful. So how come, ten years later, we're installing ramp metering again (this time on a free-flowing motorway interchange, heaven help us) in the hope that it's going to make the M62 flow more smoothly? Is there something different about this ramp metering scheme or is it just that Highways England's institutional memory doesn't stretch back as far as mine does?
For full pedant points, I don't actually believe this is the first use of ramp metering at a motorway-to-motorway junction either. I'm almost certain the blue diamond experimental ramp metering lights of the early 2000s were trialled, among other places, at the M27/M271 interchange for traffic joining the M27.
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