What Is an Assembly in AutoCAD Civil 3D?

by

An assembly in AutoCAD Civil 3D is a collection of subassemblies that are used to define the shape and behavior of a corridor. A corridor is a 3D model of a road or other linear feature that represents its design intent. The use of assemblies allows for the efficient creation and editing of complex roadway designs.

What are Subassemblies?

Subassemblies are the building blocks of assemblies in AutoCAD Civil 3D. They define specific components or elements that make up a roadway, such as pavement layers, curbs, gutters, and shoulders. Each subassembly has its own set of parameters and rules that govern its behavior.

Why Use Assemblies?

Assemblies provide a flexible and efficient way to design roadways in AutoCAD Civil 3D. By using pre-defined subassemblies, designers can quickly create complex roadway geometry with accurate cut-and-fill calculations. Assemblies also allow for the automatic updating of model elements when design changes are made.

Creating an Assembly

To create an assembly in AutoCAD Civil 3D, follow these steps:

  • Create New Assembly: Open the Toolbox palette by clicking on the “Toolbox” button on the Home tab. In the Toolbox palette, click on “Create Assembly” to open the Create Assembly dialog box.
  • Add Subassemblies: In the Create Assembly dialog box, select the desired subassemblies from the list and click “Add.”

    You can add multiple subassemblies to your assembly.

  • Edit Subassembly Parameters: After adding subassemblies to your assembly, you can modify their parameters by selecting them from the list and clicking on “Edit Parameters. “
  • Create Baseline: Once you have added and edited the subassemblies, click “OK” to create the baseline for your assembly. The baseline defines the horizontal and vertical alignment of your roadway.

Using Assemblies in Corridor Design

Once you have created an assembly, you can use it to create a corridor in AutoCAD Civil 3D. A corridor represents the design intent of a roadway and consists of a baseline (created from the assembly) and an assembly. The corridor automatically generates a 3D model that includes all the necessary elements, such as surfaces, alignments, profiles, and sections.

Editing Assemblies

To edit an assembly in AutoCAD Civil 3D, follow these steps:

  1. Open Assembly Editor: In the Toolbox palette, click on “Assembly Editor” to open the Assembly Editor dialog box.
  2. Edit Subassemblies: In the Assembly Editor dialog box, select the subassembly you want to edit from the list. You can then modify its parameters or behavior by clicking on “Edit Parameters.”
  3. Add or Remove Subassemblies: To add or remove subassemblies from your assembly, click on “Add Subassembly” or “Remove Subassembly” respectively.
  4. Save Changes: After making all desired changes, click “OK” to save your modifications and close the Assembly Editor dialog box.

In Conclusion

Assemblies are a powerful tool in AutoCAD Civil 3D that allow designers to efficiently create complex roadway designs. By using pre-defined subassemblies and their associated parameters, designers can quickly generate accurate 3D models of roadways that incorporate design intent. With their flexibility and automatic updating capabilities, assemblies streamline the design process and improve productivity in AutoCAD Civil 3D.