Assembly: AeccDbMgd (in AeccDbMgd.dll) Version: 10.3.488.0
A corridor in Civil 3D represents a path, such as a road, trail, railroad, or airport runway. The geometry of a corridor is defined by a horizontal Alignment and a Profile. Together, these form the baseline - the centerline of the 3D path of the Corridor.
Along the length of the baselines is a series of Assembly objects, which define the cross-sectional shape of the Alignment. Common points in each Assembly are connected to form feature lines (objects). Together the assemblies and feature lines form the 3D shape of a corridor.