Stope Section Coordinates
When you define the Stope Section boundary or a ground/truncation surface, a local X-Y coordinate system is used, where:
- The X-axis is horizontal and positive to the right (in the plane of the 2D section).
- The Y-axis is vertical and positive upwards (in the plane of the 2D section).
Stope Section Orientation
The relationship of the Stope Section X-Y coordinate system to the 3-dimensional orientation of the stope you are modeling, is that you are looking at a top (bird's eye view) of the pillar. The stope sides (or abutments) then go into the page to some defined Pillar Height.
NOTE: For a Rectangular Pillar shape, the Pillar Length, and Pillar Width sides are aligned with the x-axis and y-axis, respectively. The Stope Section geometry is fully defined by the Pillar Length and Pillar Width in the Input Data dialog. Rectangular Pillar coordinates cannot be directly edited.
Coordinate Values
The absolute values of the X-Y coordinates which you use to define the Stope Section boundary, is not important, except for the following cases:
- The absolute values of the X and Y coordinates of the Opening Section boundary, should have a similar order of magnitude. For example, if the X coordinates are small (near zero) then the Y coordinates should also be small. Or if the X coordinates are large, then the Y-coordinates should be large.
- If there is a very large difference in the order of magnitude between the X and Y coordinates, then numerical problems may result. For example, if X coordinates were small (near zero) and Y coordinates were very large (> 1 million), then numerical problems may occur with the analysis.
Except for these cases, you may define the Stope Section boundary coordinates anywhere in the X-Y plane, and this will not affect the results of the CPillar analysis.