Offset alignment but keep Z values

[swartaZ6NR2]

Hi There,

I have created a long alignment (-+118km) (started with 3Dpolyline, then feature line, then alignment) with XYZ points, however I want move the alignment slightly, not always uniform offsets, (ranges from 0.5m to 0.25m). How can I do this quickly to get the new XY coordinates, but keep the Z values from the original points. There are too many points to move them manually. I have attached the drawing with the first 3Dpolyline drawn. The cyan line is the new position for this line. So I want to make the cyan line my new alignment with the points just transferred to the new line. Is it possible?

Thank you

[AllenJessup]

I haven't tried it. But. I'd offset the 3D polyline past the new position. Then use the original and offset polylines to create a Surface. Create the new align and create a profile from the Surface. If you need Cogo Points. Use the Point Creation Tools to set them appropriately.

[EliANewlines · Accepted solution]

Hi @swartaZ6NR2, there is an easy way to accomplish this.

First, join all the cyan lines to make one long polyline, and convert the polyline to a feature line. Then, you can use the command ADJACENTFEATUREELEVSBYREF to set the elevations of the feature line to match the elevations of the 3D polyline next to it.

Use the 3D polyline as the reference object, select the feature line to modify it, and use an elevation difference of 0. This will make the feature line get the elevations of the 3D polyline.

One word of the caution though: the 3D polyline is very long, with over 2,000 vertices. If you run the command with a very long reference object, it will take a very long time to complete (depending on your system, it can take 10 minutes!) and may even cause Civil 3D to crash. I would first weed the 3D polyline to only have a couple hundred vertices before running the command.