Autodesk CIVIL3D - CIVILDESIGNCOMP 2007 SLM CD Tutorials Manual page 595

6 In the Section View Properties dialog box, on the Projections tab, under
3D Polylines, select the 3D Polyline- 23 row.
When you select the row, notice that the corresponding object is
highlighted in both plan and section views.
7 In the Elevation Options column, change the value to
Corridor - (1) Surface - (1).
8 Repeat Steps 6 and 7 to change the elevation of
Eastern White Pine- 21 to reference Corridor - (1) Surface - (1).
9 Click OK.
In the section view, notice that the fence marker and tree are now at the
corridor surface elevation.
Exercise 1: Projecting an Object onto a Section View | 583
Surface
Multi View Blocks