What software, and what version are you using?
While I do not know for certain (have not done a lot of design with ORD) I believe you can create a Clipped Terrain from your existing ground that has the area within your corridor limits removed. You may then be able to attach that for your cross sections.
Hopefully someone with more experience than I can better assist you.
MaryB
Power GeoPak 08.11.09.918Power InRoads 08.11.09.918OpenRoads Designer 2021 R2
Ok
As Mary B says what software are you using I will assume ORD... so forgive me if I am wrong. I use ORD and the version I use is stated below.
So in ORD we have a command under the terrain ribbon,, additional methods create a terrain from design meshes. This method way better than alternative surfaces via a template as per InRoads as it picks up your civil cells. So run that command. Then under the same pull down run create complex terrain use your active DTM as primary DTM and your new terrain as the merge DTM.
That should sort you out I hope!
By the way I put the corridor terrain in a new file as if you place it in the corridor file that will slow your corridor processing speed down a great deal.. Not a good idea that one...
I hope this helps.
Regards
Ross
If you are using OpenRoad Connect Edition, you can select what you need to obtain when processing corridors creating new feature definitions, and selecting different display settings. You can obtain Top Mesh, Bottom Mesh, Components, Linear Features, include or not Null Point Lines, Major Contours, Minor Contours, or any combination of them. If you create a Feature definition for a corridor named "Top Mesh" and set only Top Mesh in display settings, you will obtain the Top Mesh, after that you can create a terrain model from elements selecting the top Mesh as break lines, this step can be done creating a new file with a 3d seed, attaching the 3d model containing the top mesh; once you have your terrain model, you can create another file with a 3d model, then you attach the Existing groud model and the top mesh model and create your complex terrain.