In PART 1 of this series of posts, I showed you how to create a surface in Civil 3D from a shapefile that contained contour data. I also showed you some of the issues with using that command. In this post, I’ll show you how an alternative method for creating a surface from a shapefile. There are pros and cons to this method compared with the previous method:

  • Pros
    • Allows you to use all the data in the shapefile as needed.
    • Gives you control over the weeding and suplementing factors for the surface creation.
    • Allows you to use the correct options for minimizing flat areas.
  • Cons
    • There are a lot of steps to this process.
    • It potentially creates a much larger surface (data wise)

There are a lot of steps to this process so rather then detailing each step like I normally do, I’m going to summarize the steps here and then, if you need more detailed information, you can watch the included video.

  1. Import the shapefile into a drawing as AutoCAD entities (create object data from the shapefile data).
  2. Save the file as a new drawing and close it.
  3. Create a new drawing and attach the drawing with the contours to it via the Map Explorer in the Map Task Pane.
  4. Query the contours from the old drawing into the new drawing altering the elevations of the polylines to the elevation from the shapefile.
  5. Create a new surface.
  6. Add a dataclip boundary to the surface.
  7. Add the contours to the surface as contour data (make sure you toggle on all four minimize flat area options).

And that’s it! This will create a much better surface from your data but it definitely takes a lot longer to do.