Is there any way to add subassemblies directly to a plan view/DTM surface? We are working on plans for relocation of a short section of Township Road (with removal of the old road, adding a turning lane to the State Road it intersects with, and adding an entrance to a new development). I currently have a surface of the proposed improvements, with featurelines at all the grade breaks defining the road slopes, superelevation, etc. I'm going to need to cut cross sections of this and think I can do it OK by creating assemblies and corridors and targeting the featurelines. But what I would like to be able to do is pick a subassembly (say a defined pavement section), then pick the area on the plan view where it should be applied and have the slopes/gradebreaks picked up from the DTM surface (sort of like hatching the paved areas, only in 3D), then pick a subassembly for the improved shoulder and apply it to appropriate area, etc. So that I end up with a true model of the improvements. Then just create sample lines where I want cross sections and have it cut them. This would save me a lot of work defining assemblies for the intersections, places that don't daylight to existing ground (due to the removal of the old road), places where the shoulder sometimes has a grade break and sometimes doesn't due to superelev, etc.
I assume Civil 3D just doesn't allow this to be done, but thought I would check here first to be sure.
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