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We're excited about our new roundabout

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Re: We're excited about our new roundabout

#151

Post by rswail »

al_borland wrote: post #87
netsharc wrote: post #86

Earlier quoted context omitted.

Don't the exits have signs to say where the exit takes you? In Europe they'd be labeled, and highway onramps will have a different background color to indicate a highway.. Also, keeping your navigation display "north up" is much better than having one that will probably be laggy in a roundabout, confusing you on which exit to take. If all else fails, look at the signage; I remember driving and a passenger not sure if…

I think part of the issue is that it’s multi-lane. So if you’re in the right-lane to go to one road, and miss it, staying in the right-lane forces you onto the highway. If there is a car in the left lane you can’t get over to avoid it without causing an accident, or stopping, which would backup the whole circle and also risk accidents. So you end up paying the 9 mile tax. There is no way to miss your turn and easily…

I like the German roundabouts that have 3 lanes at each entry. The furthest left takes you to the 3rd exit (left hand turn), the middle takes you to the 2nd exit (straight ahead), and the right hand lane takes you the 1st exit (right hand turn).

The lanes are painted to "spiral" so that if you take the furthest left hand, by the time you get to the 3rd exit, it's the outermost lane.

Re: We're excited about our new roundabout

#153

Post by sethammons »

MostlyStable wrote: post #66
thepaulmcbride wrote: post #35

I live in the US now, but originally from Ireland. My least favourite part of US road infrastructure is the 4 way stop. They are just not good compared to a roundabout. Half the time the only way you can tell it’s an all way stop is by looking for the back of the stop signs on the perpendicular road. With a roundabout, you only have to look in one direction, and if it’s clear, you don’t even have to stop.

Wait until you find one of the distressingly common places where they build a roundabout and put stop signs on some or all of the entrances.

What does the stop provide that a yield does not? I am confused

Re: We're excited about our new roundabout

#154

Post by fransje26 »

urbandw311er wrote: post #143

UK reader here (we are pretty much 'all in' on roundabouts) I'm reading this and wondering how they'd cope with the 'Magic Roundabout': https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst... Even UK drivers struggle a bit with this one!

As the credited inventors of the modern roundabout, I've always wondered how the UK traffic planners managed to misunderstand their own creation to the point that they come up with such designs..

An other baffling design I've encountered in the UK is a roundabout with traffic lights half-way through.. Wasn't the concept based on removing traffic lights to fluidify traffic..?

As a whole, if designers come up with far-fetched designs where drivers struggle to understand what's going on, they are doing something very wrong. Assuming the average driver is already barely in control (phone distraction, screaming kids, lack of sleep, medication, subpar vehicle control, etc), the last thing you want to do is remove even more situational awareness by coming up with over-complicated designs that require serious thinking.

The argument that people will slow down because they don't understand what is happening is a fallacious one. Yes, they will slow down, but then, under stress, they will probably default to some instinctive basic reaction which has a high probability of being incorrect, leading to accidents. An illustrative example can be made with traffic videos of American roundabouts.

https://www.youtube.com/watch?v=Xu0VJ7Vo5pg

So in conclusion: Keep It Simple Stupid. (KISS)

Re: We're excited about our new roundabout

#155

Post by fransje26 »

Auracle wrote: post #128
bnralt wrote: post #95

Earlier quoted context omitted.

Online I see this mentality that roundabouts are great no matter what and it seems really strange to me. It really depends on the design of the roundabout and the traffic conditions. Where I grew up there are a lot of roundabouts, but many of them are so dangerously designed I started actively avoiding them. It’s not that you can’t poorly design a four way stop, but it seems to be much less common, for whatever reaso…

My experience driving in rural France was that nearly every intersection was a roundabout and it slowed things down dramatically. Many, many times I was the only driver within sight. Surely one of the two directions is more used and a couple of putting stop signs the other way would make more sense. Roundabouts are great sometimes, but they aren’t a magic bullet. That said we have a nasty intersection in the area on…

> My experience driving in rural France was that nearly every intersection was a roundabout and it slowed things down dramatically. [..] Surely one of the two directions is more used and a couple of putting stop signs the other way would make more sense.

Yes, that is by design. Slowing traffic down, also in relatively low-traffic areas, is one of the use-cases for roundabouts in France. Mostly around villages and/or industrial areas.

Re: We're excited about our new roundabout

#156

Post by Woeps »

tmnvix wrote: post #140

Roundabouts get a lot of praise whenever they're mentioned, and from a traffic flow perspective that's understandable - if by traffic you mean motorised traffic. For pedestrians and cyclists they are worse than the alternative (lights - or even a simple intersection) in my opinion. > Making a roundabout for everyone ctrl-f "walk", "cycl", pedes". Nothing.

> For pedestrians and cyclists they are worse than the alternative (lights - or even a simple intersection) in my opinion.

As a cycling Dutch I prefer a roundabout to a traffic light. As a roundabout doesn't force a fullstop and takeoff again. Also because stopping/get going again is more difficult for elderly/injured people.

Re: We're excited about our new roundabout

#157

Post by jen729w »

svl wrote: post #147

No discussion about roundabouts can be complete without a mention of the (mostly) Dutch "turbo roundabout", where the lane you take going into a multi-lane roundabout depends on where you want to exit, and you can't / are not allowed to switch lanes while on it: https://wiki.openstreetmap.org/wiki/Tag:roundabout%3Dturbo https://en.wikipedia.org/wiki/Roundabout#Turbo_roundabouts https://www.arcadis.com/en-us/knowledge…

Similarly this is a mandatory mention.

https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst...

Re: We're excited about our new roundabout

#158

Post by bnralt »

Arn_Thor wrote: post #129
bnralt wrote: post #111

Earlier quoted context omitted.

> The worst roundabout beats the best 4-way stop any day of the week. Sometimes there really are easy answers. Maybe you haven't seen the worst ones, then. For instance, one by my house had traffic lines which gave people the wrong impression about the right of way within the roundabout, leading to every vehicle treating driving like that. I actually drove like that as well for a long time - when you're spending ever…

I'd really like to know where this was or see some pictures of it. It's almost inconcievable that something designed like a roundabout would be more dangerous. It might indeed cause more accidents due to the kind of confusion you describe, but at the very least the angles and grading should lower speeds dramatically and result in fewer deadly accidents.

It's set up like this - busy avenue with lanes (left to right) 1, 2, and 3 enter into roundabout with circles (inner to outer) A, B, and C. The problem is that half way around the circle, where the avenue continues, A, B, and C then have lines indicating that you can either continue on the circle or move in a perpendicular direction to the circle and exit back such like this A -> 1, B -> 2, and C -> 3. And that's what everyone does. The problem is If someone from C is going around the circle, they're going to t-bone anyone going A -> 1 or B -> 2, and there's no moment to prepare because A or B is going to be suddenly cutting in front of them.

Or to visualize it another way - if you can image those intersections where there are two right turn only lanes, and one lane to the left of them that's right turn or go straight. Now imagine if all three lanes were right turn or go straight, and everyone made right turns - but if someone in the far right lane is going straight, they're plowing into the cars turning in the other two lanes.

After years they eventually fixed it and made the two outer circle lanes right turn only, which is what they should have done at the beginning. But even there they screwed up, because there's a street that enters the circle right after the right turn only signs, so if someone is entering from that direction and isn't familiar with the circle it's possible for them to ram into the other cars.

Re: We're excited about our new roundabout

#159

Post by dm319 »

A roundabout looks to be more appropriate here compared to the previous junction. The only thing that catches my eye as a UK-driver is the road markings would go against the way we would mark roundabouts in the UK. The dashed lines should indicate where the priority is - and that is on the roundabout, so in the UK there would be lines going across the road as you approach the roundabout, indicating that you are a minor road connected to a major road which has priority.

Driving in Morocco is a very special experience. Some roundabouts follow the 'priority on the right', which is a default if the junction doesn't indicate priority, in much of Europe (especially France). This means you give way to those approaching the roundabout, as they are on your right. But there are also roundabouts where you have priority on the roundabout. The only way to tell are to look at the road markings which help to indicate the priority.

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