Create Profiles

Create profiles

The Create Profiles option to create profiles of your two surface triangulations. Profiles are needed to perform volume calculations (using the Volume option). They are the end area polygons beneath each section line that when combined with the section separation give the volume.

Profiles are generated along existing section lines (created through the Create Sections option), and use the existing surface triangulations for their shape. The automatically generated profiles attempt to form a closed polygon defining the cut and fill areas beneath their section line.

A single profile is generated as follows:

1. Registration of the section line onto both surfaces.
2. At this stage there is a string defining the original surface and a string defining the new surface, both in the vertical plane of the section line. A polygon needs to be formed from these two strings. Assuming you are in a section view:
   • If the two strings intersect, and the intersection point lies in the first segment and/or the last segment of the new surface string, then the program will truncate the segment(s) at their respective intersection point(s). Any truncation point by definition at the intersection of the two surface strings, will form a vertex of the required end area polygon. An intersection anywhere else along the new surface string forces no truncation, just a switch from cut to fill or fill to cut.
   • If there is no intersection, then the program extrapolates the first and last segments of the new surface string. If either of these extrapolated segments intersect the original surface string, then they are truncated at their respective intersection point(s). As before, any truncation points will form a vertex of the end area polygon. Otherwise, the polygon is formed by joining any remaining untruncated ends (that is, non-extrapolated ends) with a straight line. The cut and fill areas of this polygon become the end area for this section line.

Note Each profile is an 'editable' object in the working layer. This layer needs to be defined before you proceed with this option.

Instructions

• Select Open Pit menu
• Select Pit Volumes submenu
• Select Create Profiles option

Select the new design triangulation, followed by the previous design triangulation. The choice of new and previous surfaces determines whether material is categorised as cut or fill.

Once selected, the profiles are created along the section lines. Use the rotate icons on the Graphics toolbar to view the profiles, or the icons on the Slice toolbar to view each profile in its vertical plane consecutively (ensure that the 'Slice-step' is the same as the 'separation' between the profiles).