AutoCAD Civil 3D

[#1]

What is the best workflow for modeling turning islands to get it to look "clean" with the desired nose returns? 

Is it possible to model the intersection without the island first (like it's all just pavement), then create the island as it's own corridor with an alignment wrapped around the curb face and somehow merge the 2 (clip out the pavement and replace with the island)?

Civil3d 2012-SP1

Windows 7-64bit

HP Z400, 16GB ram, NVIDIA Quadro 4000

[#2]

It's tough to do with corridors.  I would just make a corridor without the island and a top surface.  Make your porkchop from feature lines and make a surface.  Make a 3rd surface and paste the other 2 into it.

[#3]

Matt,

Can't you just add the feature lines to the corridor surface?

[#4]

Can you? Yes. I prefer to keep them separate.

[#5]

I agree with Matt. I like to keep the corridor surface representative of what the corridor is. I then use that surface as data in a different surface.