Inverted SPUI + Super 2 freeway combination

[yand]

The downside of inverted SPUI is the merging occurs on the passing lane, which isn't an issue for roads without passing lanes. It seems to me that inverted spuis on a super 2 would be an excellent combination. Are there any real life examples of this?

[froggie]

None that I'm aware of on a Super-2.  Seems pointless given you'd need a wider median to accommodate the median ramps, which defeats the purpose.  Nevermind the well-known safety issues of left-side exits and entrances.

[jakeroot]

None that I'm aware of on a Super-2.  Seems pointless given you'd need a wider median to accommodate the median ramps, which defeats the purpose.  Nevermind the well-known safety issues of left-side exits and entrances.

There'd also be the need for either two separate bridges for each direction of the super-2, or a decently-wide overpass for the side-road. Either certainly being pointless since super-2's are normally single-carriageway (IIRC).

[yand]

None that I'm aware of on a Super-2.  Seems pointless given you'd need a wider median to accommodate the median ramps, which defeats the purpose.  Nevermind the well-known safety issues of left-side exits and entrances.

Maybe it won't save space, but I think one of the benefits of SPUI is consolidating the surface road to a single intersection for the side street, which can then be fitted with 1 set of traffic lights, or a 2 way stop, or a 4 way stop

There'd also be the need for either two separate bridges for each direction of the super-2, or a decently-wide overpass for the side-road. Either certainly being pointless since super-2's are normally single-carriageway (IIRC).

I'm thinking more having the side road on the overpass. The overpass would only be a bit wider to accommodate the intersection, but certainly not was wide as an uninverted SPUI. I'm thinking the median ramps could be built on some sort of filled in structure, and then you would only need a short section of overpass for each side of the freeway. I guess I don't know enough about bridges to say that two short sections of overpass on a raised median cost more or less to maintain than a single longer overpass?
ms paint doodle I made: https://pasteboard.co/IeUmTnZ.png

edit: also, if the side road has thick shoulders and the overpass is expected to have shoulders, then it wouldn't need to be any wider at the intersection as vehicles could just use the shoulder space for turning

[froggie]

None that I'm aware of on a Super-2.  Seems pointless given you'd need a wider median to accommodate the median ramps, which defeats the purpose.  Nevermind the well-known safety issues of left-side exits and entrances.

Maybe it won't save space, but I think one of the benefits of SPUI is consolidating the surface road to a single intersection for the side street, which can then be fitted with 1 set of traffic lights, or a 2 way stop, or a 4 way stop

You still get those benefits with a traditional SPUI, without the hassle and safety issues of left-side exits/entrances or needing two bridges instead of one.  One could also argue that your concept requires more in the way of earthmoving and fill.

I don't know of any examples of SPUI's on Super-2s where the side road overpasses over.  There is half of an example where the side road goes underneath...the VT 9/VT 279 interchange on the east side of Bennington.