Turning left at roundabouts
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Joined: May 2002
Posts: 31,739
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From: Survivalist enclave
Read para 2 
if it's dual carriageway all round the roundabout & in and out, it could work. Sort of like where there is a left filter lane to avoid the roundabout entirely for traffic turning left, only there's not a left filter lane to avoid the roundabout entirely for traffic turning left, sort of thing.
if it's dual carriageway all round the roundabout & in and out, it could work. Sort of like where there is a left filter lane to avoid the roundabout entirely for traffic turning left, only there's not a left filter lane to avoid the roundabout entirely for traffic turning left, sort of thing.I thought I was getting it until I read Heinz's post then I started thinking about driving on the right and lost the will to live
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Joined: Aug 2001
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From: North Yorks
Originally Posted by gaddafi' timestamp='1334243211' post='21601065
[quote name='Nick Graves' timestamp='1334240553' post='21600941']
The lanes merging is an interesting one; flow studies have shown that if everyone barrelled down the fast lane & merged zipper file before the end, it disrupts flow less than tailing back & merging too early into the creepy-crawly lane. It's counter-intuitive and people probably couldn't be trusted to do it out of ineptitude/road captaincy etc.
I'd be interested to see a study into d/c roundabout d/c left-turning; it may be the case that fast-laners turning left by going round the roundabout (thus allowing the left-laners to flow consistently unimpeded) might actually improve flow rates - dependent upon other roundabout feed volumes, I'd hypothesise.
The lanes merging is an interesting one; flow studies have shown that if everyone barrelled down the fast lane & merged zipper file before the end, it disrupts flow less than tailing back & merging too early into the creepy-crawly lane. It's counter-intuitive and people probably couldn't be trusted to do it out of ineptitude/road captaincy etc.
I'd be interested to see a study into d/c roundabout d/c left-turning; it may be the case that fast-laners turning left by going round the roundabout (thus allowing the left-laners to flow consistently unimpeded) might actually improve flow rates - dependent upon other roundabout feed volumes, I'd hypothesise.
Re para 2, how could traffic be consistently unimpeded in the left lane if they have to give way to traffic coming from the right?
The left lane would not be impeded any more than the right lane . One from the left then one from the right then one from the left etc etc.
[/quote]
In New Zealand the signs are very simple - a big sign beforehand that says "Merge Like A Zip" and shows cars merging in turn.
Why does it have to be any more complicated than that?
Joined: Aug 2005
Posts: 2,907
Likes: 70
From: Lincolnshire Wolds
Originally Posted by Heinz '57' timestamp='1334264217' post='21602379
[quote name='gaddafi' timestamp='1334243211' post='21601065']
[quote name='Nick Graves' timestamp='1334240553' post='21600941']
The lanes merging is an interesting one; flow studies have shown that if everyone barrelled down the fast lane & merged zipper file before the end, it disrupts flow less than tailing back & merging too early into the creepy-crawly lane. It's counter-intuitive and people probably couldn't be trusted to do it out of ineptitude/road captaincy etc.
I'd be interested to see a study into d/c roundabout d/c left-turning; it may be the case that fast-laners turning left by going round the roundabout (thus allowing the left-laners to flow consistently unimpeded) might actually improve flow rates - dependent upon other roundabout feed volumes, I'd hypothesise.
[quote name='Nick Graves' timestamp='1334240553' post='21600941']
The lanes merging is an interesting one; flow studies have shown that if everyone barrelled down the fast lane & merged zipper file before the end, it disrupts flow less than tailing back & merging too early into the creepy-crawly lane. It's counter-intuitive and people probably couldn't be trusted to do it out of ineptitude/road captaincy etc.
I'd be interested to see a study into d/c roundabout d/c left-turning; it may be the case that fast-laners turning left by going round the roundabout (thus allowing the left-laners to flow consistently unimpeded) might actually improve flow rates - dependent upon other roundabout feed volumes, I'd hypothesise.
Re para 2, how could traffic be consistently unimpeded in the left lane if they have to give way to traffic coming from the right?
The left lane would not be impeded any more than the right lane . One from the left then one from the right then one from the left etc etc.
[/quote]
In New Zealand the signs are very simple - a big sign beforehand that says "Merge Like A Zip" and shows cars merging in turn.
Why does it have to be any more complicated than that?
[/quote]
Simples, innit?
Joined: Mar 2001
Posts: 31,181
Likes: 58
From: Hertford
Originally Posted by MarkB' timestamp='1334305430' post='21603902
[quote name='Heinz '57' timestamp='1334264217' post='21602379']
[quote name='gaddafi' timestamp='1334243211' post='21601065']
[quote name='Nick Graves' timestamp='1334240553' post='21600941']
The lanes merging is an interesting one; flow studies have shown that if everyone barrelled down the fast lane & merged zipper file before the end, it disrupts flow less than tailing back & merging too early into the creepy-crawly lane. It's counter-intuitive and people probably couldn't be trusted to do it out of ineptitude/road captaincy etc.
I'd be interested to see a study into d/c roundabout d/c left-turning; it may be the case that fast-laners turning left by going round the roundabout (thus allowing the left-laners to flow consistently unimpeded) might actually improve flow rates - dependent upon other roundabout feed volumes, I'd hypothesise.
[quote name='gaddafi' timestamp='1334243211' post='21601065']
[quote name='Nick Graves' timestamp='1334240553' post='21600941']
The lanes merging is an interesting one; flow studies have shown that if everyone barrelled down the fast lane & merged zipper file before the end, it disrupts flow less than tailing back & merging too early into the creepy-crawly lane. It's counter-intuitive and people probably couldn't be trusted to do it out of ineptitude/road captaincy etc.
I'd be interested to see a study into d/c roundabout d/c left-turning; it may be the case that fast-laners turning left by going round the roundabout (thus allowing the left-laners to flow consistently unimpeded) might actually improve flow rates - dependent upon other roundabout feed volumes, I'd hypothesise.
Re para 2, how could traffic be consistently unimpeded in the left lane if they have to give way to traffic coming from the right?
The left lane would not be impeded any more than the right lane . One from the left then one from the right then one from the left etc etc.
[/quote]
In New Zealand the signs are very simple - a big sign beforehand that says "Merge Like A Zip" and shows cars merging in turn.
Why does it have to be any more complicated than that?
[/quote]
Simples, innit?
[/quote]
Because we're famously a nation of Road Captains & General Arseholes. They're generally more 'societal' on the incontinent.
Also, all the Asians here would all complain that Reisverschluss is racist; a Rice Fastener is worse than a wedlock or a padlock.
It's a lot tastier and more nutritious than a Reissverschluss, though! Never get your tongue caught in one, though.
Joined: Aug 2005
Posts: 2,907
Likes: 70
From: Lincolnshire Wolds
Missing more than one "S" of late!
Joined: Mar 2001
Posts: 31,181
Likes: 58
From: Hertford
The right amount!
Too early merging, or stopping to merge (!) is why the polite system fails.
I think barrelling right up to the cones is considered rude & road captains will close the gaps.
Somewhere one has to synchronise speeds & find a gap before they're gone.
Since some people are children & won't let ANYONE in front of them, it's awkward.
Maybe if they introduced Reissverschliessungskameras & fined anyone who failed, it might improve discipline. Actually, Reissverschliessungskanonen would be better; blast the buggers to damnation!
Too early merging, or stopping to merge (!) is why the polite system fails.
I think barrelling right up to the cones is considered rude & road captains will close the gaps.
Somewhere one has to synchronise speeds & find a gap before they're gone.
Since some people are children & won't let ANYONE in front of them, it's awkward.
Maybe if they introduced Reissverschliessungskameras & fined anyone who failed, it might improve discipline. Actually, Reissverschliessungskanonen would be better; blast the buggers to damnation!
