Trying to grade a Ramp from a Road

[mdemers]

I've had a consistant problem with grading for a while and wonder if I can get some help.

I'm trying to grade a temporary ramp from a road to OG. I have an OG surface, and a Road surface. Whenever I try to grade my ramp from the crest of the road to OG 10% nothing happens (no errors nothing). But if I delete the road surface and all its feature lines, then grade the ramp to OG then there is no problem at all.

Is there a maximum number of surfaces you can have overlap each other in Civil 3D 1007 SP2? What can cause this?

Thanks in advance

Canon

[petrocat]

Did you try putting the grading on a different site? I'm not certain this will work, but from other posts in the newsgroup, site topology is sometimes the kink in the process.

[mdemers]

Petrocat

thanks for the reply I'll try that tommorrow morning.

Canon