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xkcd #2932: Driving PSA
(imgs.xkcd.com)
Alt text:
This PSA brought to you by several would-be assassins who tried to wave me in front of speeding cars in the last month and who will have to try harder next time.
Except the ones with two lanes that can both exit or continue
I have never seen a roundabout here in Australia that allows for these sorts of conflicting movements, that would be asinine. Are you saying there's multiple lanes that can exit or go straight such that someone in the inside lane can turn out in front of someone continuing around in the outside lane? Is this a North American thing? Of course that would result in accidents, don't build your bloody roundabouts like that!!
I drive through three lane (six lane road) roundabouts all the time and no one gets hurt. In fact I have to drive through two such roundabouts to get to the nearest freeway.
There are so many like this in the US. I don't understand who thought they were a good idea or why they keep getting made
I'm absolutely calling BS. I've never seen such a thing and wagering that you are just confused about what lanes can do what (or you're just making shit up). There are several roundabouts near me where an inside lane can turn out or go straight, but in all of those cases all lanes further out are required to turn out. The people that design traffic patterns aren't idiots, but there's no shortage of idiot drivers that can't follow even the simplest patterns.
If you want to insist, all you need to do is link to such an intersection in google maps so I can look at the aerial view. I'm honestly curious how they would paint the traffic lanes to indicate what you're describing.
Even on that, a driver in the right lane must exit. If they want to continue to the left, they are required to make a lane change, in which case all lane change rules would apply.
I’ve got some near to me that both lanes can exit, but you must be in the inside lane to keep going round. They’re very strangely designed.
I don't see any conflicting movements here. I have a roundabout almost exactly like this just around the corner. It's not complicated.
I think it's probably got more to do with the drivers. There are plenty of roundabouts like this where I am in Aus, and they get used just fine. Over here they have a far lower rate of accidents than other types of intersections. We never have 4 way stops either, we just put a roundabout there.
Imagine a roundabout where most of the traffic flows straight on only one of the streets. Things would improve a lot of you gave that street the right of way and cut a shortcut on the middle of the roundabout, wouldn't them?
(/s by the way, but a lot of transit engineers to really believe in this. Unironically.)
You jest, but we do kind of have something like this in Melbourne, Australia. Except the vehicles that get to cut through the middle of the roundabout are Trams. Plus while they're trundling through, everyone else has to stop and wait for them.
I was not joking when I said a lot of transit engineers believe on it.
That one is one of the least bad I've seen. Try imagine it on the cross of two roads (actual high-speed roads, country-side). I've seen many of those.
I'm bloody sorry but did you just say this is one of the least bad you've seen?? Let me give you a different view:
Trams traverse the traffic lanes at three points, as well as one making an immediate left turn exit. There are four traffic lanes. Royal Parade has inside lanes and service lanes.
But I also don't have to imagine that at all, those are common here too and I've never had a problem at them:
Notice how the approaching lane at the bottom left has an artificial curve added to it? It's traffic calming to help slow down cars before they get to the roundabout itself.
That second picture of yours is just a normal roundabout. Try making one of the roads pass directly through it. And don't change the signaling.
I've noticed that the tram line cuts the traffic in 3 points. What is the speed of that street? Anyway, the tram line is clearly signed in a way that can be noticed on the photo. And every car there is making a weird curve, nobody is speeding anyway.
You'll have to be specific, all five of the roads that enter this roundabout are different, none actually continue through it. I think the maximum speed limit in the area is 60km/h though.
Edit: Also, the weird looking building in the first picture? That's the Royal Melbourne Hospital. There is A Lot going on at this roundabout. Though I guess as far as it not being "bad" it is probably the best intersection they could have built for this location. The cycle length if it were a signalised intersection would be insane.