Civil 3D: Expressing Elevations on 2-tier Structures

May 4, 2022 Leo Lavayen

Civil 3D has a couple of Structures that are 2-tier with cylindrical uppers and box shaped lowers:

  • Rectangular Structure 2-Tier Rectangular Frame
  • Rectangular Structure 2-Tier Circular Frame


The goal is to label both the Top of Structure (Rim) and Top of Box Elevations.  The first part is easy, there is a pre-defined property to populate the Civil 3D label for upper: Insertion Rim Elevation

The tricky part is figuring out the top box elevation.  There is NO property found in the Text Component Editor for the Structure labels:

The solution is simple, create a custom Expression to calculate the elevation value.  Civil 3D already knows the values it is just a matter of building the calculation:

The using the known values, shown below, the manually created Profile View Labels (pink) at the Rim and Top of Box are matched.

To create the needed calculation go to the Toolspace palette > Settings tab > Structure collection > Label Styles > Expressions > right click select New...

Here, you can assign a Name (that will be used in label component), Description (optional) and Build the Expressions itself:

{Insertion Rim Elevation}-({Rim to Sump Height}-{Barrel Height})