Autodesk Civil 3D: Tips and Tricks!

There are a lot of little things that go unnoticed in Civil 3D. Probably due to the fact that there are a million icons and commands! Whether they are hidden away within your Toolbox, or several layers deep within the ribbon, there are some really good tools that are often overlooked. Here are some of my favorite little tasks, some new, and some oldies but goodies!

Linear Feature & Point Extraction (ReCap / Autodesk Docs)

Point cloud data feature extraction allows you to extract reference points and linear features, such as a curbs and gutters as well as points, such as street signs, fire hydrants and light poles, from a point cloud dataset.

These tools are available in the Autodesk Construction Cloud viewer. Published ReCap point cloud projects have access to these extraction tools in the viewer.

From within the point cloud viewer, you will find the Feature Extraction command along the toolbar on the bottom of the screen.

Once selected, you place your view direction in the direction you wish to extract your linear objects.

You can also set up pre-determined point types with feature codes for easy import into Civil 3D, as well as custom templates and naming convention for you extracted linear features. This will help speed up the import/processing of data in Civil 3D.

Once you’ve adjusted your points on the section view, select Start Auto Extraction. You’ll visually see the features being created!

If the extraction algorithm runs into an issue in the point cloud data that it is following, auto extraction will pause. A warning dialog will then display, offering two options:

  • STOP. Extraction stops to allow the cross section to be adjusted. Extraction will need to be started again once complete.
  • IGNORE. The extraction continues to the next cross section interval until the threshold is not met again.

Stage Storage w/ User Defined Contour Analysis

Need a quick volume analysis from a pond?  Need that analysis every 0.5’ within the pond?  The Stage Storage Tool in Civil 3D is your new best friend!

First, you need to decide what interval you need to report on.  Your surface style will control the results/interval within the report. For example, if I want the following pond volumes in 0.50’ intervals, I simply edit the surface style to display the correct interval, prior to running the analysis.

However, let’s take this one step further by using the User Defined Contour analysis from within your surface properties. Sometimes you may want to see the high-water mark, a pressure elevation or maybe a floodplain elevation. This is a great tool, and coupled with the State Storage command can help you identify true volumes much easier.

After you have edited your style to display the User Contour and your preferred contour interval, select the surface you wish to analyze, and from the Analyze panel of the ribbon, choose Stage Storage.

This will launch the report dialog box, fill in the blanks as needed, and select DEFINE BASIN.

You want to then select Define Basin from Polylines and select the Extract Objects from Surface button.

Select the surface, select DEFINE back on the dialog box and select up to the polyline you wish to analyze. The dialog box should reappear with your results and notice the oddball contour interval based on our user defined contour! You can save this report to a text file, or even better, save it as a file to be used within SSA!!

Expressions in Civil 3D

An example for expressions is to use them to aid in labeling cut vs. fill labels in a volume surface. For example, you may want to display your CUT in red, and you FILL in blue.  To do so, we will set up a couple quick expressions.

1. First, ensure you have a VOLUME surface created. This goes without explanation but thought I would mention it anyway!

2. Create two expressions, one for the Cut Text height and one for the Fill Text height.

3. Name this first expression Cut-Text. Use this as the expression:

a. IF({Surface Elevation}<0,0.10/12,0.00000001)

4. Name this second expression Fill-Text. Use this as the expression:

a. IF({Surface Elevation}<=0,0.12/12,0.00000001)

What we are doing here is creating a super small text that will NOT show up once we place our labels. These expressions are slightly different, we won’t use these in our label composer, but we will use these to adjust the text height and differentiate Cut v. Fill.

5 .Create a label style that has 2 components, Cut and Fill text.  These components reference the Surface Elevation, but in the text height property, you will set the corresponding expression (Cut/Fill).

6. Change the CUT component color to RED.

7. Change the FILL component to BLUE.

8. Test this out by using your new label style to label a surface!!

Misc. Expressions

Here are a few other simple expressions I’ve used in Civil 3D.

Truncate your elevations.  An example of this is displaying an elevation of 132.67 as 32.67:

  • {Surface Elevation}-100*TRUNC({Surface Elevation}/100)

2 Point Slope Arrow – Arrow always pointing downhill

  • IF({Surface Slope} <= 0, 0, pi)
  • This expression gets applied to the Rotation Angle of the direction arrow component.

Pipe True Slope

  • ({Start Invert Elevation}-{End Invert Elevation})/{2D Length - To Inside Edges}

Length in Meter – Display both (any object)

  • {Segment Length} *.3084

Slope Distance AND Horizontal Distance in a label (Use on lines, polylines, figures and feature lines)

  • SQRT({General Segment Length}^2-(ABS({General Segment Start Z}-{General Segment End Z})^2))

Civil 3D Corridor Transitions

Civil 3D now has added controls for transitioning subassembly parameter values across a defined station range. This allows for greater flexibility in modelling complex roadway features and saves time setting up target linework, separate regions, and multiple assemblies.

You can also create linear, slope, and elevation transitions on corridor feature lines which reduces the need for complex, custom subassemblies.

Some of the top use cases include:

  • Daylight slope transitions
  • ADA ramps and driveways
  • Bus bays
  • Turn lanes

To create corridor transitions, first, select the corridor.

On the ribbon, on the Modify Corridor panel, select Edit Corridor Transition.

If the corridor has multiple baselines, you are prompted to select a baseline. Select the baseline in the corridor to which you want to add the transition. This may be an alignment or a feature line.

The Corridor Transition Panorama vista is displayed, and a prompt is displayed at the command line to select the subassembly to transition.

Hover over your corridor, on the subassembly you want to transition, and select it on the screen. After you select the subassembly, a list of available parameters in the subassembly that you can transition is displayed.

Select the parameter to transition from the list.

Select the start station of the transition.

Enter the parameter value at the start station. The default value is displayed in Panorama Vista.

Select the end station of the transition.

Enter the parameter value at the end station.

Specify the transition type.

If needed, continue to specify transition information by specifying the end station for the next transition. In this example, I’ve transitioned for a drive access by removing the curb and gutter back. Once completed, select Apply from the top right of the panorama.

NOTE: You can copy and paste transition sets to the same corridor, a different corridor, or a corridor in another drawing. In the Corridor Transition Panorama vista, right-click a transition or a transition set to access the copy and paste commands.


There are always forgotten commands, or simple tips and tricks that may help us boost our productivity.  I have been doing this for over 15 years now and I learn something every time I ask a question, or simply sit back and listen to others speak.  Feel free to send me any of your favorite hidden commands or tips and tricks you have learned along your Autodesk journey.

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