Roundabouts in the Sky

[kalvado]

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.

[SSR_317]

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.

[pderocco]

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.

[Urban Prairie Schooner]

I've always admired the aesthetics of the Airline Hwy/Causeway Blvd 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.

[cjw2001]

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

[kphoger]

Just imagine what'll happen if a drunk driver plows through that thing at 100 mph!   

[cjw2001]

Just imagine what'll happen if a drunk driver plows through that thing at 100 mph!   

Never underestimate the power of a greater fool to find a way to evade a foolproof design.