Grading Object passes through surface in batter.

[acullinan86]

Hi All,

I'm trying to grade to an existing batter. I want to calculate volumes for various stages of the backfill. I have set up a feature line to hug the structure that will be built and created a grading at 0% (flat) to target the surface of the existing excavation (batter). On the straight areas it is behaving as expected (green), however when it changes direction, it producing and arc which is going slightly past the batters (circled red), so I end up with some cut volumes which I should not have. 

How can I fix this, is there a way to make it generate the true daylight / intersection line with the batter all the way around? 

[AuditInPaperSpace]

Hello!

I was able to reproduce this issue. I don't really have any insight as to why the grading feature is doing that, other than that grading features can get a little weird when projecting arcs outwards. 

I might try filleting the corners of your starting feature line, instead of the chamfer you have. That seems to give better results.

However, if you're just trying to calculate how much fill is required to get up to a certain contour level, you can do that without grading features. You just extract the desired contour line from your surface, add it to a new surface as a breakline, and create a volume comparison surface between the existing, and the surface you just created. You can also have a surface draw a contour line at any arbitrary elevation, if the elevation you want is not an even number.

Let me know if this helps!

[brian.strandberg]

I will tell you when I am using grading objects with right-angle corners, I find I get better success if I put a slight fillet on those corners.  This way the points will radiate out at the corner instead of doing that 90 degree thing you are seeing.

Hope this helps - thanks.

[lim.wendy]

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