So, are there any roundabouts that are elevated and lets say there is another primary route that flows through on the surface? Maybe over a river or other natural feature?
So, like, any grade-separated roundabout interchange where the through-route goes underneath?
Quote from: kphoger on November 01, 2022, 06:40:58 PM
So, like, any grade-separated roundabout interchange where the through-route goes underneath?
Yes
Then here's a good one in Greece: https://goo.gl/maps/atL6DZpHvXLPnuHa8
Here's one in Italy, this fits the criteria of going over a natural feature:
https://www.google.com/maps/@38.9119738,16.5912067,314m/data=!3m1!1e3
A Norwegian roundabout over a roundabout:
(https://pbs.twimg.com/media/Dgj9VmuXUAAuQ0_.jpg)
Quote from: Bruce on November 01, 2022, 08:22:31 PM
A Norwegian roundabout over a roundabout:
(https://pbs.twimg.com/media/Dgj9VmuXUAAuQ0_.jpg)
I believe that you mean a traffic circle over a roundabout. :spin:
Do you mean something like this?
https://www.google.com/maps/@-34.8024695,-54.5737754,709m/data=!3m1!1e3
Quote from: CoreySamson on November 01, 2022, 10:24:42 PM
Do you mean something like this?
https://www.google.com/maps/@-34.8024695,-54.5737754,709m/data=!3m1!1e3
What purpose does this one serve? Seems like they could have just built a jersey barrier between two lanes if they wanted to keep the traffic separated.
Quote from: Avalanchez71 on November 01, 2022, 10:50:51 PM
Quote from: CoreySamson on November 01, 2022, 10:24:42 PM
Do you mean something like this?
https://www.google.com/maps/@-34.8024695,-54.5737754,709m/data=!3m1!1e3
What purpose does this one serve? Seems like they could have just built a jersey barrier between two lanes if they wanted to keep the traffic separated.
I believe the reason stated on this forum was to slow down traffic on the bridge, since apparently tons of fisherman use the bridge to fish. Don't quote me on that though.
Quote from: CoreySamson on November 01, 2022, 10:53:56 PM
Quote from: Avalanchez71 on November 01, 2022, 10:50:51 PM
Quote from: CoreySamson on November 01, 2022, 10:24:42 PM
Do you mean something like this?
https://www.google.com/maps/@-34.8024695,-54.5737754,709m/data=!3m1!1e3
What purpose does this one serve? Seems like they could have just built a jersey barrier between two lanes if they wanted to keep the traffic separated.
I believe the reason stated on this forum was to slow down traffic on the bridge, since apparently tons of fisherman use the bridge to fish. Don't quote me on that though.
Yeah, I'm going to call bullshit on that claim. I doubt they have been to Uruguay to know people fish on the bridge. They built the bridge before anyone ever fished on it, so it's not like they re-built the bridge because motorists were driving too fast while people fished. They could've easily built a pier to permit fishing away from traffic.
It's a traffic calming measure (https://web.archive.org/web/20160623231807/http://national.suntimes.com/world-news/7/72/2503378/this-circular-bridge-encourages-drivers-to-slow-down-and-take-in-the-view). There are pedestrian crossings on each end and the shape is designed to slow traffic.
(https://upload.wikimedia.org/wikipedia/commons/f/f9/Bridge_Laguna_Garz%C3%83%C2%B3n%C3%82%C2%A1.jpg)
I've always admired the aesthetics of the Airline Hwy/Causeway Blvd (https://goo.gl/maps/qnMKgjeLRqv7uHF29) interchange in suburban New Orleans. I've never been there, so I can't speak to its functionality.
Heathrow arrival stacks. More than one loop may be required.
Quote from: pianocello on November 02, 2022, 09:23:45 PM
I've always admired the aesthetics of the Airline Hwy/Causeway Blvd (https://goo.gl/maps/qnMKgjeLRqv7uHF29) interchange in suburban New Orleans. I've never been there, so I can't speak to its functionality.
Those are common in Britain at freeway-to-freeway interchanges. Never seen one over here before.
The 106th street roundabout over I 69 works quite well in Fishers IN. https://www.google.com/maps/@39.9419778,-86.0185414,191m/data=!3m1!1e3
The google maps image from above is a bit distorted so some better views are available here:
https://www.youtube.com/watch?v=r_fL4rqvZG0
Live traffic camera (usually pointed at the roundabout but may be pointed elsewhere during incidents on the highway) https://511in.org/@-86.01933,39.94322,14?show=incidents,normalCameras,trafficSpeeds,electronicSigns,stationsAlert,weatherWarningsAreaEvents,plowCameras,flooding#camera/791/2413281424
Quote from: cjw2001 on November 03, 2022, 04:06:24 PM
The 106th street roundabout over I 69 works quite well in Fishers IN. https://www.google.com/maps/@39.9419778,-86.0185414,191m/data=!3m1!1e3
The google maps image from above is a bit distorted so some better views are available here:
https://www.youtube.com/watch?v=r_fL4rqvZG0
Live traffic camera (usually pointed at the roundabout but may be pointed elsewhere during incidents on the highway) https://511in.org/@-86.01933,39.94322,14?show=incidents,normalCameras,trafficSpeeds,electronicSigns,stationsAlert,weatherWarningsAreaEvents,plowCameras,flooding#camera/791/2413281424
I wonder what was the cost of such interchange. Must be very non-trivial...
Quote from: kalvado on November 03, 2022, 04:24:21 PM
Quote from: cjw2001 on November 03, 2022, 04:06:24 PM
The 106th street roundabout over I 69 works quite well in Fishers IN. https://www.google.com/maps/@39.9419778,-86.0185414,191m/data=!3m1!1e3
The google maps image from above is a bit distorted so some better views are available here:
https://www.youtube.com/watch?v=r_fL4rqvZG0
Live traffic camera (usually pointed at the roundabout but may be pointed elsewhere during incidents on the highway) https://511in.org/@-86.01933,39.94322,14?show=incidents,normalCameras,trafficSpeeds,electronicSigns,stationsAlert,weatherWarningsAreaEvents,plowCameras,flooding#camera/791/2413281424
I wonder what was the cost of such interchange. Must be very non-trivial...
The cost is in the description on the YouTube video ($21.7 million). This was a new from scratch interchange so they were able to start with a clean slate. The old 106th overpass was removed and replaced with the new interchange.
Quote from: cjw2001 on November 03, 2022, 04:06:24 PM
The 106th street roundabout over I 69 works quite well in Fishers IN. https://www.google.com/maps/@39.9419778,-86.0185414,191m/data=!3m1!1e3
The google maps image from above is a bit distorted so some better views are available here:
https://www.youtube.com/watch?v=r_fL4rqvZG0
Live traffic camera (usually pointed at the roundabout but may be pointed elsewhere during incidents on the highway) https://511in.org/@-86.01933,39.94322,14?show=incidents,normalCameras,trafficSpeeds,electronicSigns,stationsAlert,weatherWarningsAreaEvents,plowCameras,flooding#camera/791/2413281424
That looks like a really well-designed interchange. It's a shame we don't see more of those built. These are way better than dumbbell or dogbone interchanges, though I'll still take those over a standard diamond.
The Shirlington interchange (https://www.google.com/maps/@38.8405036,-77.0850734,518m/data=!3m1!1e3) on I-395 in Arlington County, VA is similar but not quite the same.
Quote from: JoePCool14 on November 04, 2022, 09:28:45 AM
It's a shame we don't see more of those built. These are way better than dumbbell or dogbone interchanges, though I'll still take those over a standard diamond.
My suspicion is that they're more commonly installed
under the highway than
over, such as here: https://goo.gl/maps/b7i9MXe1JqX98Btx6
Quote from: kphoger on November 04, 2022, 12:54:10 PM
Quote from: JoePCool14 on November 04, 2022, 09:28:45 AM
It's a shame we don't see more of those built. These are way better than dumbbell or dogbone interchanges, though I'll still take those over a standard diamond.
My suspicion is that they're more commonly installed under the highway than over, such as here: https://goo.gl/maps/b7i9MXe1JqX98Btx6
And next question is how that is different from the ol' good diamond...
Quote from: Occidental Tourist on November 02, 2022, 01:35:01 AM
It's a traffic calming measure (https://web.archive.org/web/20160623231807/http://national.suntimes.com/world-news/7/72/2503378/this-circular-bridge-encourages-drivers-to-slow-down-and-take-in-the-view). There are pedestrian crossings on each end and the shape is designed to slow traffic.
Why would they design the bridge so pedestrians could cross the street to walk in the middle? If the bridge was straight, wouldn't they just walk along the sidewalk they're already on?
Quote from: jeffandnicole on November 04, 2022, 01:27:09 PM
Quote from: Occidental Tourist on November 02, 2022, 01:35:01 AM
It's a traffic calming measure (https://web.archive.org/web/20160623231807/http://national.suntimes.com/world-news/7/72/2503378/this-circular-bridge-encourages-drivers-to-slow-down-and-take-in-the-view). There are pedestrian crossings on each end and the shape is designed to slow traffic.
Why would they design the bridge so pedestrians could cross the street to walk in the middle? If the bridge was straight, wouldn't they just walk along the sidewalk they're already on?
This is a bridge on an unpaved road, probably most of the traffic is tourists - both walking and driving...
Quote from: kalvado on November 04, 2022, 01:12:50 PM
Quote from: kphoger on November 04, 2022, 12:54:10 PM
Quote from: JoePCool14 on November 04, 2022, 09:28:45 AM
It's a shame we don't see more of those built. These are way better than dumbbell or dogbone interchanges, though I'll still take those over a standard diamond.
My suspicion is that they're more commonly installed under the highway than over, such as here: https://goo.gl/maps/b7i9MXe1JqX98Btx6
And next question is how that is different from the ol' good diamond...
Yield signs.
Quote from: kphoger on November 04, 2022, 02:03:14 PM
Quote from: kalvado on November 04, 2022, 01:12:50 PM
Quote from: kphoger on November 04, 2022, 12:54:10 PM
Quote from: JoePCool14 on November 04, 2022, 09:28:45 AM
It's a shame we don't see more of those built. These are way better than dumbbell or dogbone interchanges, though I'll still take those over a standard diamond.
My suspicion is that they're more commonly installed under the highway than over, such as here: https://goo.gl/maps/b7i9MXe1JqX98Btx6
And next question is how that is different from the ol' good diamond...
Yield signs.
I would rephrase that as
priority of left turning "to highway" traffic over straight through traffic.
Quote from: cjw2001 on November 03, 2022, 04:06:24 PM
The 106th street roundabout over I 69 works quite well in Fishers IN. https://www.google.com/maps/@39.9419778,-86.0185414,191m/data=!3m1!1e3
The google maps image from above is a bit distorted so some better views are available here:
https://www.youtube.com/watch?v=r_fL4rqvZG0
Live traffic camera (usually pointed at the roundabout but may be pointed elsewhere during incidents on the highway) https://511in.org/@-86.01933,39.94322,14?show=incidents,normalCameras,trafficSpeeds,electronicSigns,stationsAlert,weatherWarningsAreaEvents,plowCameras,flooding#camera/791/2413281424
I used to commute across the old 106th Street grade separation over I-69 for a couple years before that particular job ended. But that was before the current interchange was built. As part of the project to build it, they had to relocate a historic farmhouse.
Quote from: Avalanchez71 on November 01, 2022, 10:50:51 PM
Quote from: CoreySamson on November 01, 2022, 10:24:42 PM
Do you mean something like this?
https://www.google.com/maps/@-34.8024695,-54.5737754,709m/data=!3m1!1e3
What purpose does this one serve? Seems like they could have just built a jersey barrier between two lanes if they wanted to keep the traffic separated.
It guarantees that there is always someone driving on the bridge with the sun directly in his eyes.
Quote from: pianocello on November 02, 2022, 09:23:45 PM
I've always admired the aesthetics of the Airline Hwy/Causeway Blvd (https://goo.gl/maps/qnMKgjeLRqv7uHF29) interchange in suburban New Orleans. I've never been there, so I can't speak to its functionality.
Most people seem to get the gist of that interchange pretty easily, seeing that it has existed for 60+ years. The only hazard is the death-merge onto SB Causeway Blvd. More recent modifications have eliminated the other death-merges that used to exist.
Quote from: cjw2001 on November 03, 2022, 04:06:24 PM
The 106th street roundabout over I 69 works quite well in Fishers IN. https://www.google.com/maps/@39.9419778,-86.0185414,191m/data=!3m1!1e3
The google maps image from above is a bit distorted so some better views are available here:
https://www.youtube.com/watch?v=r_fL4rqvZG0
Live traffic camera (usually pointed at the roundabout but may be pointed elsewhere during incidents on the highway) https://511in.org/@-86.01933,39.94322,14?show=incidents,normalCameras,trafficSpeeds,electronicSigns,stationsAlert,weatherWarningsAreaEvents,plowCameras,flooding#camera/791/2413281424
Here is some additional video of the interchange that popped up in my YouTube feed... https://www.youtube.com/watch?v=QbvgnQ9dCRw
Just imagine what'll happen if a drunk driver plows through that thing at 100 mph! :evilgrin:
Quote from: kphoger on November 08, 2022, 08:50:34 PM
Just imagine what'll happen if a drunk driver plows through that thing at 100 mph! :evilgrin:
Never underestimate the power of a greater fool to find a way to evade a foolproof design.