Yesterday, I mentioned that Corridors are made from Alignments, Profiles, and Assemblies. So what are Assemblies?
Assemblies are a collections of Subassemblies (i.e. Sidewalk, Curb & Gutter) that are placed together to form a roadway cross-section. Civil 3D comes with many stock Sub-Assemblies to use.
Because of Civil 3D 2005's dynamic nature, even after Corridors have been built changes to an Assembly can cause the Corridor it is referenced by to update automatically.
Assemblies are applied at user specified intervals along an alignment and they connect to the next Assembly along that alignment. The image used yesterday shows the embedded Assemblies in the Corridor