AutoCAD Civil 3D Corridor Modeling Tutorial – 1 | Assemblies | Subassemblies | Subassembly Composer | Concrete Median. This tutorial shows you how to develop corridor designs using assemblies and subassemblies in AutoCAD Civil 3D. Topics covered in this tutorial are:
0301 Introduction to assemblies and subassemblies
0302 Creating a subassembly with subassembly composer
0303 Creating points and links with subassembly composer
0304 Defining the concrete median
source