civil 3d fundamentals: pasting surfaces

image Have you ever wanted to make a surface that was the composite of two other surfaces?

For example, would you like a complete finished ground model consisting of roads, ponds, lot grading and more combined with the original existing ground?

Do you dream at night about it being dynamic to the original surfaces?

Well, dream no more.  Surface pasting is your answer.

Read on…

Step 1: Make a new, blank surface.  I like to call mine Composite FG.


Step 2: Right click on Edits and choose Paste Surface.  Choose your biggest “platform” surface, which is usually your existing ground, or maybe existing ground stripped or something like that.


Step 3: Right click on Edits and choose Paste Surface.  Choose your second surface, which could be a corridor based surface or grading object surface, etc.

**Note the preview pane contains a list of each surface you pasted into the Composite FG.  You can removed pasted surfaces at any time by right clicking in here.


Step 4: Investigate your drawing, isolating the Composite FG surface.  Note that the corridor surface TIN has replaced EG TIN where the two overlap making one integrated surface object.



The best part is- this composite surface is dynamic to both the EG and the corridor surface.  So if your surveyors come in with new points or your profiles change (and therefore your corridor is rebuilt), this Composite FG will always react immediately.

My favorite technique is to build the composite surface on day one and use it as the rim/rule target for my pipe networks and similar tasks that would otherwise require me to wait for my smaller FG surfaces were ready. 

 As I continue to design my project, I add more elements to my composite surface and make edits, but I never have to tell my pipe networks to seek another surface, nor do I have to figure out which surface works for which structures, and other surface based tasks.


  1. fairhilleng says:

    Thank you for this post. I think a lot of people would appreciate more like this.

    What do you recommend for a composite surface style for final plotting if the EG surface extends beyond the limits of grading? Typically we like to display solid proposed contours and background (dashed) existing contours that are not modified. Would a boundary around the Composite FG at the limits of grading be the best bet? The EG surface could then be displayed with a background style.

    John Mascari, Fair Hill Engineering, Civil 3D 2008

  2. Tim McGivern says:

    This is great, but doesn’t seem to work if you want to “stitch” two or more surfaces together. How can this be done?