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I'm calculating partial TIN volumes using Polygon Volume in ArcMap 10.7. I've done this hundreds of times using arcpy and for the most part, it works fine (Height Field = MAX; Reference Plane = BELOW). However, sometimes the routine calculates a volume and a surface area of zero, respectively, without any error messages.
My data can be downloaded here. I have provided one example of a TIN and a shapefile that works, and one example of a combination that doesn't. I cannot figure out the difference between the two.

EDIT:
Following @Vince, I've used Check Geometry on the shapefile (as it does not work with TINs), which gave me the error notification:
Could not find spatial index.
When Repair Geometry did nothing to fix this, I simply ran Add spatial index.
After that, the Check Geometry routine gave me no further errors - however, I still get an area and volume of zero when I use Polygon Volume.

When I use other shapefiles (that overlap with the TIN to a larger or smaller extent) the volume/area calculation runs fine. So, I suspect the error has to lie within the shapefile - but I have no idea what caused it.

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    Try running Check Geometry and/or Repair Geometry to identify and correct topology errors. A "bowtie" (quadrilateral with 2nd and 3rd vertices swapped) will usually show zero area. – Vince Mar 25 at 12:07
  • Thanks very much for the info! Check geometry did indeed show some errors, but my problem is not solved. I've updated the question accordingly. – Florian Mlehliv Mar 25 at 12:33
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    @FlorianMlehliv, which column did you use as height? Your TIN has heights ranging from 2400-2250, but all the values from the table your are much lower. I did a test run, and it worked fine for me. – alecsx Mar 26 at 8:55
  • @alecsx: Thanks for the test run! I use the "MAX" column as height. But the height values for the shapefile ("MIN" and "MAX") are approximately in the same range as the TIN (2463-2243), so there should be no problem. Which column did you take when you succeeded with the test run? – Florian Mlehliv Mar 26 at 9:09
  • I used one of your hazard columns, and now I tried it with the MAX and it also works, just set your reference plane to BELOW, because if you set it ABOWE, you will get 0 values. desktop.arcgis.com/en/arcmap/10.3/tools/3d-analyst-toolbox/… – alecsx Mar 27 at 11:20
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I was unable to find the reason for this not working for me but for others, however, this alternative should work:

Generate a copy of the TIN, edit this TIN with the polygon and then use Polygon Volume or Surface Volume.

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