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Training
DifficultybeginnerAdded2027.0Statusdraft

Road Widening (Civil 3D essentials)

Civil 3D has very powerful tools for road widening. The road width can be driven by a polyline, feature line or by an alignment. In the example below, an offset alignment will be used. An offset alignment is an alignment linked to the main alignment, and users can apply widening to this type of alignment.

  1. To create an offset alignment, select an alignment in the plan view, in the contextual ribbon select the Offset Alignment command:

  2. Set the No. of offsets on left to 1 and on right to 0 (an offset alignment will only be created on the left side). Specify the Incremental offset on left and set the Alignment Style, see the image below:

  3. Created offset alignment (dashed line which overlaps with road edge):

  4. To add a widening to an offset alignment, select an offset alignment and use the Add Widening command from the contextual ribbon:

  5. When prompted Create Widening Portion as a New Alignment?, select No:

  6. Specify the Start and End stations and enter the Widening Offset. The widening offset is measured from the road centreline:

Created widening on the offset alignment (thick line):

  1. Go to the Corridor Properties, Parameters tab and click on the Set All Targets button:

  2. Click on the text <None>, which is next to Left SuperelevationAOR at the Width or Offset Targets section:

  3. For the Object type to target use Alignments, select the offset alignment (offset alignment has offset values stipulated in the name) and click Add:

Result, the road edge follows the offset alignment: