To Merge two different grading surfaces in Civil 3D

Merging of gradings or grading surfaces does not work in Civil 3D it is a program limitation.

Solution:

• If you want to merge or have gradings interacting they need to be placed in the same site. However, the results might not look as expected
• The following workaround can be applied to merge overlapping grading surfaces:
  • Create a new and empty surface in Civil 3D
  • Use "EditSurfacePaste" to insert the Existing Ground (EG) and the Grading Surface 1
  • Create a Crop Surfcace the does not contain the overlapping surface areas between Grading Surface 1 and 2
  • In a new DWG insert the Crop Surface and create/add Grading Surface 2