If you prefer to only use alignments and Civil 3d corridors only for the basic road layout and use feature lines to connect up intersections, draw knuckles and cul-de-sacs then follow this guide. It provides detail on how to add Allsite roading objects in place of these specialized civil 3d objects. When Level AI runs it will then return feature lines connecting the the civil 3d corridor sections. You can mix and match full civil 3d corridor objects and Allsite road objects for different parts of the design.
Note: Corridor assemblies must still meet Allsite requirements just as if using full corridors.
Setting up intersections
Draw your curb returns as polylines, use the back-of-curb to define line. You can draw multiple strings to define a sidewalk.
Select the 3 (or more) polylines and convert them to a road modifier
Use the modifier extended data to set attributes. It is important to set the most outer modifier to an outside edge as this defines the corridors extent. If using multiple modifiers, it is just the outer modifier that needs this set. Additionally set the sub assembly (these are populated based on the surrounding corridors assembly).
Draw polylines to connect the surrounding corridor regions. Make sure they are snapped to the alignment at edge of region. Convert them to Road->Road (Layout Assist)
Configure longitudinal grade information for the intersection on the road polyline objects.
The intersection is now complete. When running Level AI prepare you may see a Road Region disconnected validation warning, this can be ignored.
Follow similar steps for cul-de-sacs, but draw the road centreline to finish at the centre of the cul-de-sac.
Click the below animation to get a step-by-step guide to drawing an intersection
Results
When Level AI results are run, roading feature lines are added to the model connecting the intersection and defining the curb. All feature lines have extended data added to them to allow for easy object selection.
Alignment profiles will have 'gaps' where the feature lines define the intersection profile (ie joining the 2x sections of the corridor/alignment running through)
