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DifficultybeginnerAdded2027.0Statusdraft

Assemblies (Civil 3D essentials)

Assembly objects contain and manage a collection of subassemblies which are used to form typical sections of linear structures.

An assembly is created by adding one or more subassembly objects, such as travel lanes, kerbs, and side slopes to the assembly baseline.

  1. To create an assembly, go to the Home tab in the ribbon and select the Assembly – Create Assembly command to place it in model space. If the design grid is not being used, it is good practice to place assemblies close to a longsection:

  2. Specify the Name and Assembly Type:

Created assembly baseline:

  1. Open the Tool Palettes window with the icon indicated in the image below. The tool palettes contain a library of subassemblies which can be added to an assembly. Users can program subassemblies or use the Subassembly Composer to develop custom subassemblies:

The Tool Palettes window has various tabs that contain subassemblies for specific types of structures:

A road assembly with kerbs and sidewalks will be created in the next section.

  1. In the Tool Palettes go to the Lanes tab and select LaneSuperelevationAOR:

  2. Specify the parameters in the Properties window as shown in the image below:

  3. Select the assembly baseline marker to add the subassembly to the assembly:

Note: Every subassembly consists of points connected with links and the closed areas form shapes. Shapes are used for material volume calculations. Points, links and shapes have names which are called Codes in Civil 3D. Codes are displayed in an assembly. Point codes are Pink, link codes are Orange and shape codes are Green. One object can have multiple codes.

  1. In the Tool Palettes go to the Curbs tab and select UrbanCurbGutterGeneral:

  2. Specify the parameters in the Properties window as shown in the image below:

  3. Select the outside-top point of the LaneSuperelevationAOR subassembly (green cross) to add the gutter subassembly to the assembly:

  4. In the Tool Palettes go to the Curbs tab and select the UrbanSidewalk:

  5. Specify the parameters in the Properties window as shown in the image below:

  6. Select the outside-top point of the UrbanCurbGutterGeneral subassembly to add the sidewalk subassembly to the assembly:

  7. In the Tool Palettes go to the Basic tab and click on BasicSideSlopeCutDitch to define the cut and fills:

  8. Specify the parameters in the Properties window as shown in the image below:

  9. Select the outside-top point of the UrbanSidewalk subassembly to add the BasicSideSlopeCutDitch subassembly to the assembly:

Note: BasicSideSlopeCutDitch subassembly contains a channel in the cut condition. If there is no need for a channel, the subassembly LinkSlopeToSurface from the Generic tab can be used.

  1. Select all the subassemblies on the right-hand side, right-click and select the Mirror command from the menu. If you want to Move, Copy or Mirror a subassembly NEVER use the AutoCAD commands, only use the right-click menu commands. When using the AutoCAD commands, the assembly might display correctly in the layout mode, but the corridor will be incorrect, some of the subassemblies will move up or down by a few meters when rebuilding the corridor.

Use the AutoCAD commands when you need to Move or Copy the entire assembly, only select the baseline of the assembly to copy it. Subassemblies which are properly connected to the assembly will be moved or copied as well.

  1. Select the baseline marker to mirror the subassemblies to the other side:

  2. Select the LaneSuperelevationAOR on the left-hand side, right-click and select Properties or Subassembly Properties:

  3. Change the Use Superelevation parameter to Left Lane Outside. This will ensure that the correct superelevation is used on the left-hand side:

  4. The Assembly Properties can be reviewed in the Assembly Properties window. Select an assembly baseline, right-click and select Assembly Properties from the menu:

In the Information tab the assembly can be renamed:

In the Construction tab the assembly type can be changed, the assembly construction can be reviewed, and the subassemblies' parameters can be modified:

In the Codes tab all the codes from the subassemblies are displayed: