1. Create Terrain models for each of the upper and lower surfaces. Save these surfaces in separate files. NOTE: the surfaces do not have to have the same x,y coordinate points, nor do they have to cover the same plan view area.
2. Open the Terrain file which contains the upper surface (the surfaces can intersect each other, see Intersection of two surfaces below).
4. In the Volumes / Surface Properties dialog set Surface B to be the bottom Terrain file. Disable Calculate Intersection Features and Volumes by Polygon. Press OK.
5. When the calculation is complete the volumes are reported in the Volume Reporting dialog.
Volumes by Polygon
Volumes can be calculated inside one or more polygonal boundaries. These boundaries are defined by features in the current Terrain file with feature property surface boundary. If you have created a feature and wish to use it for volume calculations you can change its property using in the Feature Properties dialog.
Volume Reporting
When the volume calculation is complete the results are displayed in the Volume Reporting dialog. The volume of material enclosed between the two surfaces is reported as either Above A or Below A. The volume of material enclosed between the two surfaces is reported as either above A or below A. Eg. if Surface A is an excavation surface and Surface B is the original ground then Volume Above A is cut volume and Volume Below A is fill volume.
Intersection of two surfaces
When two surfaces cross, it is possible to calculate the intersection line. When the calculation is complete the intersection polyline(s) is saved as a feature with the prefix SSCT.
