In 2-lane motorways, during the peak hours, lane 1 is usually occupied by lorries and everyone else travel via lane 2 making it almost like a single carriageway!
But in 3 (or more) lane motorways assuming lane 1 reserved for lorries (well - sort of) there are 2 lanes available for everyone else.
So theoretically even though 3-lane motorways have 33% extra road space (over 2-lane ones), traffic probably moves twice as fast.
I understand it may be an extreme generalisation but that's what I noticed by travelling in parallel stretches of M1 and A1(M). I somehow feel more comfortable in M1 because I can maintain my own pace without someone kissing my bumper in lane-2 or having to switch frequently between lane-1 and 2.
It will be interesting to see if any proper research data is available for this.
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I'm going to appear pedantic here, but three-lane carriageways have 50% more space than two-lane carriageways. Conversely, two-lane carriageways have 33% less space than three-lane carriageways.
Such simple comparisons don't take account of 'elephant racing' on two-lane carriageways and CLOCkers on three-lane carriageways.
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>> I'm going to appear pedantic here, but three-lane carriageways have 50% more space than two-lane
>> carriageways. Conversely, two-lane carriageways have 33% less space than three-lane carriageways.
2 lane motorway is 2 lanes + hard shoulder (normally)*
3 lane motorway is 3 lanes + hard shoulder (normally)
2 lanes +Hard shoulder is a lot better than 2 lane dual carriageway (and safer IMHO)
Playing percentages and the HS a 3 lane Mway +HS is 33% bigger than 2 lane+HS and conversely the 2 lane Mway+HS is 25% smaller than 3 lane+HS
* Some motorways were not built with HS eg M90 (parts of) in Fife
Some with Motorways with HS are having it modified to become another lane.
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>> 2 lanes +Hard shoulder is a lot better than 2 lane dual carriageway (and safer IMHO)
Safer - agreed
But how it is better than 2-lane dual carriageway (assuming no roundabout/signal in dual carriageway)?
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>> But how it is better than 2-lane dual carriageway (assuming no roundabout/signal in dual carriageway)?
>>
Somewhere to exit Stage left in the event of something nasty in lanes 1&2
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That's why I was careful to refer to them as carriageways, not motorways. I'd assume the traffic carrying capacity of a hard shoulder to be zero.
>>* Some motorways were not built with HS eg M90 (parts of) in Fife
I understood the definition of a motorway to be two or more carriageways in each direction separated by a centre refuge, with a hard shoulder alongside the inside lane?
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>> I understood the definition of a motorway to be two or more carriageways in each direction separated by a centre refuge, with a hard shoulder alongside the inside lane?
Some of our intelligent MPs have decided that opening HS to traffic will reduce the congestion without (!) spending any money.
So, only difference between MWays and dual carriageways is now lack of traffic signals and roundabouts.
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>> opening HS to traffic will reduce the congestion without (!) spending any money
M1 junction 10 - junction 13 works are estimated to cost between £326m - £503m. The works are taking 4 years to complete, and all we are getting is a strengthened hard shoulder and some signs and cameras.
www.highways.gov.uk/roads/projects/4482.aspx
They did the same thing up at junctions 22 - 25 a couple of years ago for a bargain £340m. And yet they still won't put Catthorpe right.
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I understood the definition of a motorway to be two or more carriageways in each direction separated by a centre refuge, with a hard shoulder alongside the inside lane? Bath Tub.
Not always we have a road here as you prescribe with a 40mph speed limit.
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So, to conclude, are we agreed that a three-lane motorway can carry more traffic than a two-lane one? And that a hard shoulder makes a useful place to go in an emergency?
What next? As John Humphrys once inadvertently put it, applehood and mother pie?
}:---)
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Reduce of congestion is a pipe dream .Lots of family's with two cars..
People having to travel futher to their place of work.Amount of traffic during peak times.
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"Lots of family's with two cars..
People having to travel futher to their place of work"
Recession = less cars + less places of work.
Problem sorted!
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If the recession was the answer.Drive in any town at. peak times no less cars.
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>> If the recession was the answer.Drive in any town at. peak times no less cars.
>>
>>
Also applies to motorways. Fewer jobs about so more people forced into long commutes to find work.
I know people commuting 100+ miles through no other reason than it being a better option than the dole queue.
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>> If the recession was the answer.Drive in any town at. peak times no less cars.
>>
>>
Not sure I agree with that. Norwich seems to me less busy than the last few years even now the children have gone back to school. A11, the main road to London also seems quieter with the traffic queues at Elvedon, a major bottleneck seeming shorter of late. A year or two of serious recession and inflation will see a lot of second/third family cars being sold.
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>> assuming lane 1 reserved for lorries (well - sort of)
Assumptions like that are a big part of the problem.
I've just got back from a 300 mile round trip in a Transit van*, 80% of which was motorway. I did 70-75mph all the way, and was in lane 1 for more than half the time.
>> travelling in parallel stretches of M1 and A1(M)
>> someone kissing my bumper in lane-2 or having to switch frequently between lane-1 and 2
Knowing the Beds/Herts stretches of both motorways VERY well, I would suggest that's something specific to the A1(M), rather than something that applies to all 2-lane motorways Movilogo. :)
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>> I've just got back from a 300 mile round trip in a Transit van*, 80%
>> of which was motorway. I did 70-75mph all the way, and was in lane 1
>> for more than half the time.
In the last week I've done round trips from Northampton to Sheffield and to a village near Stourbridge. About 400 miles in all, using the Berlingo which is at it most comfortable a tad under 70. Like Dave I spent lots of time in lane 1, though more so on Sunday than yesterday; the M42 was chocker around 18:00.
Realxing, reasonable progress made and the fuel gauge is still around the 25% mark.
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Currently running round Sicily in a Fiat 500.
Here the number of marked lanes ( where they exist at all) is merely
Guidance, a suggestion, to the number of cars the authorities think should fit in that carriageway. It appear to be at least two less than the locals think should fit
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Reminds me of driving in Naples in the rush hour a few years ago. Whenever there were traffic lights, what had been (say) four lanes of moving traffic now became at least six stationary.
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For many exceptions to the definition of a 'motorway', may I refer the collective to the excellent (IMO) website, Pathetic Motorways (www.pathetic.org.uk)
Unfortunately no link available at present as the site seems to be down, but its great when it works.
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It's working now, Alastair, and what a great site! (What the Internet, or at least the WWW was invented for, if you ask me.) Best of all it explains the mess of junction numbers and motorway stubs where the M4 passes Maidenhead, as I do every working day.
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2-lane vs 3-lane motorways - bathtub tom
