Subassemblies are the basic building blocks of a corridor design.
A subassembly is an AutoCAD drawing object (AECCSubassembly) that defines the geometry of a component used in a corridor section. Through the tool palette and tool catalogs, AutoCAD Civil 3D provides preconfigured subassemblies for components such as travel lanes, curbs, side slopes and ditches. These subassemblies are defined by a set of points, links, and optionally closed areas referred to as shapes.
The subassemblies provided with AutoCAD Civil 3D have built-in intelligent behavior. They can automatically adapt to conditions such as superelevation and cut or fill requirements. For example, a side slope subassembly has variable slopes that change automatically depending on the depth of cut along the corridor. In fill conditions exceeding a given depth, the shoulder automatically widens to include a guardrail or barrier.
After you determine the kinds of subassemblies to use, make sure they are available through an AutoCAD Civil 3D tool palette or tool catalogs available through the Content Browser. For more information, see the Content Browser Help.
In addition to ready-to-use subassemblies, AutoCAD Civil 3D also lets you create your own custom subassembly objects from polylines, or design more sophisticated ones using a .NET language. (See AutoCAD Civil 3D Developer’s Guide.)
A subassembly that has not yet been applied to a corridor is considered to be in layout mode. After you create a corridor, all subassemblies included in the corridor model are considered to be in modeling mode.
You can use a special type of subassembly called a conditional subassembly that automatically inserts other specified subassemblies when certain conditions are met.
For example, a conditional corridor assembly could contain two ConditionalCutOrFill subassemblies. The first ConditionalCutOrFill subassembly can be configured to apply a ditch subassembly when a cut condition exists. The second ConditionalCutOrFill subassembly can be configured to apply a guardrail, shoulder, and daylight to surface when a fill condition exists. Using conditional subassemblies enables you to reduce the number of corridor regions and assemblies that you have to maintain.
An assembly that contains one or more conditional subassemblies can be referred to as a conditional assembly. For more information, see Creating Conditional Assemblies, or the tutorial exercise Creating an Assembly with Conditions.
Topics in this section
- The Subassembly Object
A subassembly is an AutoCAD Civil 3D drawing object (AECCSubassembly) that defines the geometry of a component used in a corridor section.
- Subassembly Styles
Use code set styles to control the appearance of subassemblies.
- Subassembly Settings
Use subassembly settings to control the behavior of subassembly-related commands.
- Subassembly Properties
Specify administrative, parameter and codes information using subassembly properties.
- Subassembly Collection (Settings Tab)
Use the Subassembly collection in the Settings tree to manage subassembly settings and commands.