Is it possible to elevate a variable line using a known line & known slope
You could do this with a corridor. Make Line 1 your master alignment and Line 2 a reference line. Create a template with an Offset/Slope instruction. Instead of specifying an offset, select 2D Line. For the slope enter 1:3. There is an example of this in the Working with Corridors tutorial in TBC. You might want to have a look at this to see how it's done.
I had it in edit mode too long. Somebody was quicker with the corridor solution :-)
There are several ways. Not one dedicated command as long as I know, but quickly to do.
But be warned, depending on how ZigZagi your Line 1 is the outcome between the two ways might be different. Elevation computation when offsetting the line seems to be different to corridor approach. But most likely will only be an issue with hard corners and large elevation differences in Line 1
One would be to offset Line 1 beyond Line 2 and type 1:3 or 33.3% into the Vertical offset field. Depending on the offset value the vertical offset will recompute if you "Tab" to the next field.
Then create a surface with those 2 lines and drape line 2 onto that surface using the "Change Elevation" command.
The other more complicate way would be to use the corridor template instructions. Create an Alignment with Line1. Create a Corridor. Create a Template. Use Offset/Slope and use Line 2 as Offset.
Once you have your corridor surface click on it in the project explorer and use the explode command.
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