This should be really simple but I still haven't figured out how to do this with AutoCAD 2014. In Eagle Point I could select a 3D polyline and project it to a boundary offset, not simply a constant offset. I was then asked to input slope and voila, a second 3D polyline projected to another line. How do you all do this? Thanks, frustrated.
Sounds like Projection Grading may be what you're trying to accomplish?
Feature Lines and Projection Grading can also be used together.
In any case you're going to want to become familiar with Feature Lines as they're a very powerful tool.
Civil 3D has 4 criteria types for grading. Surface, Distance, Elevation and Relative Elevation. Looks like you are looking for a boundary target, which Civil 3D does not offer - directly.
What I do in that situation is grade out from the source feature line at the desired slope to a distance beyond the target boundary.
Then convert the target boundary polyline to a feature line (Feature Line from Objects command) and get the elevations from Surface, which is the surface made from the grading object.
Regards,
Mike
because in C3D you do it with the elevation by adjacent FL tool