Separate materials in material lists are interacting with one annother.

[Coffee_Aided_Design]

Hello everyone, I have a two materials in a material list. One cut and one fill. The cut is meant to be subtracted from the fill to give me what I am calling structure backfill. The problem is that the areas are being calculated incorrectly (Section line  1+30.00). When I drop these materials into separate material lists they behave as expected. Any ideas?

Fill calculated wrongFill calculated correctlyCut calculated correctly

[Coffee_Aided_Design]

Hello everyone, I have a two materials in a material list. One cut and one fill. The cut is meant to be subtracted from the fill to give me what I am calling structure backfill. The problem is that the areas are being calculated incorrectly (Section line  1+30.00). When I drop these materials into separate material lists they behave as expected. Any ideas?

Fill calculated wrongFill calculated correctlyCut calculated correctly

[Civil3DReminders_com]

The Ground Removed and Ground Fill allow you to add additional surfaces to the list. I'd suggest adding the surfaces and then setting the Below/Above option to the correct value. This should give you the desired results. 

In this case it looks like you need to add Strcuture Backill Datum to the other group and the Top Pipe Structure Backfill to the other group in the correct order. 

[Civil3DReminders_com]

The Ground Removed and Ground Fill allow you to add additional surfaces to the list. I'd suggest adding the surfaces and then setting the Below/Above option to the correct value. This should give you the desired results. 

In this case it looks like you need to add Strcuture Backill Datum to the other group and the Top Pipe Structure Backfill to the other group in the correct order.