Since Civil 3D was first introduced, grading, in my opinion, has been the least reliable part of the program. Due to the incessant crashing, it always left a bad taste in my mouth and I tried to avoid it at all costs. Well, I finally broke down and gave it some more testing in Civil 3D 2011 and was pleasantly surprised. I’m hoping to start a dialog on this blog about different perspectives on grading in Civil 3D, and where the program falls apart. I’ve seen two methods of dealing with grading in Civil 3D.
- Create a new Site and a new grading group. This will in turn create a new proposed surface which drives the design.
- With the new empty surface created, you may now add feature lines, polylines, points, etc. to the proposed surface and watch the design update in real-time.
- If the grading objects became too complex, the drawing and/or surface would become unusable.
- More grading would lead to more crashing.
- “Automatic Surface Generation” could easily cause crashing .
- Confusion between which entities take precedence, the surface data added or the grading object.
- Infills would be required to fix holes created by the gradings.
- Create a site and grading group just to be able to use the daylighting portion of grading objects. Do not turn on “Automatic surface generation”.
- Create a proposed surface and use feature lines, points, and polylines to design the surface.
- When daylighting is needed, use a grading object, but explode the grading object and use the footprint polyline as a breakline in the surface.
This solution seems to yield the least amount of crashes, but it comes at a price.
- Gradings are not linked to a surface. If you need another daylighting design you must create another grading object, explode it again, and then add it to your surface yet again (reminds me of Land Desktop).
- More control over the surface generation, however, much less automated control.
I would typically use Method #1, and when Civil 3D would fail for some grading task I would move to method #2. However, when I found myself starting with method #1, after a while it would crash a lot, forcing me to use method #2. Please share any experiences with Civil 3D Grading (good or bad) that you’ve had so that we all can gain from everyone’s expertise.