The roundabout thread

[Jeroen669]

Freeway on ground-level has the advantage that traffic will decelarate more easily on off-ramps and a better acceleration on on-ramps.

[R.A.K.cancer]

we

[Harry]

Originally Posted by Norsko

Was this the most simple way of making traffic floting?

I know this roundabout quite well, and it works surprisingly well. It has been there for about 35 years and succeeds because drivers, as they should, treat the junction as 5 separate mini-roundabouts. There is a lot of holding capacity in this design and, because it is possible to navigate from one exit to another in more than one way, congestion here is very rare.

[volkhen]

Originally Posted by Xusein

My parents and I went to Boston and had to go on one of these, they were scared to death!

What they were afraid of?

[Xusein]

...crashing into another car while trying to get out of the circle.

[GENIUS LOCI]

That remembers me Chevy Chase in National Lampoon's European Vacation, when Griswolds are in London and keep on driving for hours around a roundabout as they're afraid to exit (in England, obviously, roundabouts are clockwork)

"Look kids, Big Ben..."

[volkhen]

Originally Posted by Xusein

...crashing into another car while trying to get out of the circle.

They should have used a outer lane... It's impossible to crash. But...

Here in Poland we have thousands of roundabouts and still I don't like driving on inner lane.
There is a most dangerous roundabout in Poland. It's located in my city There are an 360 accidents on this roundabout per year. So it's one for a day. I always choose outer lane there .
The reason is:
You need to give priority when you are on inner lane to the cars on outer lane. The only problem is that the streets are not symetrical so sometimes this rule don't apply. I hope that you know what I mean.


ps. sorry for any mistakes in English.

[nils16]

I hate to drive in multilanes roundabouts...
Switzerland have also many.

[Verso]

Originally Posted by volkhen

There is a most dangerous roundabout in Poland. It's located in my city There are an 360 accidents on this roundabout per year. So it's one for a day.

Same here, accidents almost every day in one of our roundabouts.

[bartheius]

Its about 1.9 Kilometers Guys and have only one way traffic.. not have traffic from inner there is a temple inside it no entry for public vehicles there..


http://maps.google.com/maps?ll=10.52...6&t=h&hl=en-GB

[eskandarany]

BIG roundabouts are nice
otherwise imo optimised traffic signals are best. though for heavy traffic loads each situation must be considered separately.. certainly roundabouts cause massive tailbacks so unless there are signals ON them (which there often are in britain in large roundabouts) otherwise not a gd idea

[Scion]

Xiamen, China

[mgk920]

Originally Posted by Scion

Xiamen, China

Looks like a lot of drivers are forgetting the 'yield before enter' rule here....



Mike

[ChrisZwolle]

Yeah such backups are mostly due to bad driver behaviour than due to the design.

[Rebasepoiss]

The biggest roundabout in Estonia...and it really is a roundabout, not just a road in a circle:

[Glodenox]

Originally Posted by Scion

Xiamen, China

Strange... On that roundabout it seems that the people ON the roundabout have to give way... In that case I think it's more due to the design. It would be much more efficient with just 2 lanes (at the very maximum 3).
EDIT: looked at Google Earth and saw that the feeder lanes had just 3 or 2 lanes 800 meters before the roundabout. I don't understand why they'd do that: a 6-lane roundabout is much less efficient than a 2-lane roundabout... They better let 2 lanes enter the roundabout and the third one can be used to go directly to the right. Even more efficient would be a tunnel going straight under the roundabout for the most-used direction (or two tunnels if that's possible) and letting just one lane go through to the roundabout (one with the normal roundabout priority rules: if you're on the roundabout, you've got priority because traffic on it has to keep flowing).

Many of the comments I see in this topic I simply can't understand. It all depends on the characteristics of the intersecting roads whether certain structures are better than other. Sometimes roundabouts are the best solution by far, sometimes traffic lights work better. In case driving education seems to be rubbish (seems to be the case for the USA looking at the responses here), traffic lights are a lot safer because they "think" for you.

All in all, I love roundabouts in all its forms as long as they're appropriate for that specific intersection. They don't necessarily have to be bigger than a traffic light intersection.

Greetings,
Glodenox

[Glodenox]

Here's one of the worst roundabouts of Belgium which is luckily being transformed into a conflict-free intersection: Intersection Lummen.



Many accidents have happened there because of this ageing structure. It's slightly elliptical because of the angle at which the highways intersect.

Greetings,
Glodenox

[Verso]

How about the Roundabout around the world?
Worlds largest roundabouts
Roundabouts: good idea?

Too many threads about roundabouts.

[ChrisZwolle]

Not anymore

I could merge them because nearly all posts in those threads were from different timespans, so the thread is not really mixed up.

[Verso]

Good! I thought there was another thread about them.