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Stephane Dumas:

--- Quote from: Alex on April 10, 2022, 08:03:48 AM ---
--- Quote from: rte66man on April 09, 2022, 11:37:52 AM ---Never seen a SPUI shifted like that. I wonder where else you can find one.

--- End quote ---

There is a similar SPUI at Interdtate 225 and Alameda Avenue in Aurora, Colorado.

--- End quote ---

As well as another one at St.Paul, Minnesota at I-694/Rice St. where a former diamond interchange was converted into a SPUI.
https://goo.gl/maps/kxqz78NCUJyjtUq36

rte66man:

--- Quote from: Stephane Dumas on April 26, 2022, 08:53:24 AM ---
--- Quote from: Alex on April 10, 2022, 08:03:48 AM ---
--- Quote from: rte66man on April 09, 2022, 11:37:52 AM ---Never seen a SPUI shifted like that. I wonder where else you can find one.

--- End quote ---

There is a similar SPUI at Interdtate 225 and Alameda Avenue in Aurora, Colorado.

--- End quote ---

As well as another one at St.Paul, Minnesota at I-694/Rice St. where a former diamond interchange was converted into a SPUI.
https://goo.gl/maps/kxqz78NCUJyjtUq36

--- End quote ---

That interchange shows as an offset roundabout, not a SPUI. Does Google have it wrong?

Stephane Dumas:

--- Quote from: rte66man on April 27, 2022, 11:02:42 PM ---That interchange shows as an offset roundabout, not a SPUI. Does Google have it wrong?

--- End quote ---

Google have it right, I guess it could be a variant who could be called "SRUI" (Single Roundabout Urban Interchange). However there a real shifted SPUI where Rice Street meet MN-36. https://www.google.com/maps/@45.007569,-93.1037842,1584m/data=!3m1!1e3
 

mrsman:

--- Quote from: Alex on April 10, 2022, 08:03:48 AM ---
--- Quote from: rte66man on April 09, 2022, 11:37:52 AM ---Never seen a SPUI shifted like that. I wonder where else you can find one.

--- End quote ---

There is a similar SPUI at Interdtate 225 and Alameda Avenue in Aurora, Colorado.

--- End quote ---

This is a fantastic design.  One thing about most of the normal SPUIs that I have been to is that in order to make left turns, you have to swoop across the whole intersection.  In some ways it feels a bit unnatural, in that in making your left turn, you basically have to drive a little bit in opposite direction traffic to then meet up with the onramp.

Take this example in Pikesville, MD:

https://www.google.com/maps/@39.3843465,-76.7335423,3a,37.5y,284.35h,82.79t/data=!3m6!1e1!3m4!1sYvnON3RVudYkNpZeRt6qbA!2e0!7i16384!8i8192

You are sitting at the stop line waiting for a green arrow to make a left.  You have to go all the way to where that green sign is on the left to make it to the onramp.  This is probably one of the main reasons that permissive lefts at SPUIs are rare, even for single lane left turns.

But the intersection in Aurora, CO feels like a normal intersection.  A direct left turn can be made in the normal fashion.  Much more intuitive (and probably safer).

The off-set SPUI seems pretty rare, but one half of this interchange in design is not so rare.  It usually occurs where there is a major street that is parallel to the freeway.  (Some times the major street is the old highway that was replaced by the freeway).  If that parallel street is set to end at another major street that is also serviced by a freeway exit and entrance, it is a convenient design to get traffic on the parallel street directly on the freeway.

West Main Street entrance onto US 101 in Ventura, CA.  An offset half-SPUI to get business route traffic directly onto freeway:

https://www.google.com/maps/place/Ventura,+CA/@34.2822034,-119.3180284,17.3z/data=!4m5!3m4!1s0x80e9ad155097394d:0x24eff57c367aeae8!8m2!3d34.2804923!4d-119.2945199


roadman65:
https://itd.idaho.gov/news/construction-begins-next-week-on-the-i-90-sh-41-interchangePost Falls to receive a SPUI, but not one that meets under or over the freeway.

https://itdprojects.org/projects/i90sh41ic/
Look and you’ll see on ITD’s page how it will look.

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