Surface basics

Last updated: 2021-06-29

Total video time: 03:58

Exercise files: srfc-basc-data-begin-c3d20.zip

Start with 12345678\Design\Surfaces\Surf-Ex.dwg

srfc-basc-01.mp4 3:58

Civil 3D surfaces are a dynamic object representing elevation through a series of triangles; TIN surface triangles or gridded surface triangles.

Change surface style

  1. Select surface > right-click menu > select Surface Properties...
    1. Surface Properties dialog box
      1. Default styles box
        1. Surface style dropdown: EX TrianglesOK

Tip: TIN triangles are irregular. Gridded triangles are even or squared; two right-triangles that define the grid.

Surface borders and boundaries

Borders: Indicates where the edge of the triangles is located.

Outer Boundaries: Prevent triangles from being made outside the boundary line.

Inner or Hide Boundaries (aka Void boundaries): Prevents triangles from being made inside its shape.

Show Boundary: Drawn inside the Hide Boundary and are used to display triangles that the Hide Boundary removed.

Volume surface

Comparison of volume between two surfaces, TIN or grid.

  1. Toolspace > Prospector tab > right-click Surfaces > select Create Surface
    1. Create Surface dialog box
      1. Type dropdown: TIN volume surface
      2. Properties box
        1. Surface style dropdown: EX TrianglesOK
        2. Name: TIN Vol
        3. Base Surface: Exist
        4. Comparison Surface: Grading
      3. OK
  2. Toolspace > Prospector tab > expand Surfaces > right-click TIN Vol > Surface Properties...
  3. Surface Properties - TIN Vol dialog box
    1. Surface style: Vol Elevation
    2. OK