Expand segment to DTM surface
You use this function to make a copy of a selected segment and expand it up towards a DTM surface, or contract it down towards a DTM surface. You can use this, for example, to find out where a proposed open pit would intersect the surface.
Prerequisites:A segment is open in Graphics . The surface of interest is loaded into the surface layer using the LOAD DTM SURFACE function. A design gradient is set.
To run this function: Choose Design > Expand segment > To DTM surface, or...
Instead of progressing all the way to the DTM surface, it is also possible to progress a fraction of the height between the points on the selected segment and the DTM surface. You can use a maximum bench height and limiting elevation to ensure that the expanded segment does not exceed a specific maximum bench height or elevation of interest.
Note: This function works on both open and closed segments.
Select the segment to be expanded
Select the segment of interest with the mouse to display the EXPAND SEGMENT TO DTM form.
Fields on the Expand segment to DTM form
| Field | Description |
|---|---|
| String number | The string number of the selected segment. Display only. |
| Segment number | The segment number of the selected segment. Display only. |
| Minimum Z value | The minimum Z value of the selected segment. Display only. |
| Maximum Z value | The maximum Z value of the selected segment. Display only. |
| Define the method of expansion | |
| % of height to DTM |
The percentage of the distance to the DTM by which the points of the segment are projected. To ensure that each point on the selected segment achieves the elevation of the surface in the new segment, type a value of 100. If you want the new segment to progress only a fraction of the distance to the surface, type the appropriate percentage, for example 50 to progress half of the distance to the surface, or 25 to progress one quarter of the distance to the surface. |
| Maximum bench height |
The maximum bench height you can mine to. The projection of the selected segment towards the surface can result in a design which is unacceptable for the type of mining equipment which is used, or the design might create dangerous mining conditions. You can restrict the bench heights to ensure that they do not exceed a predetermined maximum limit by entering the maximum bench height here. If you do not want to limit bench height, use a high value such as 9999.
|
| Z direction |
The Z direction is used to determine whether the points on the selected string are projected up to the surface or down to the surface.
|
| Limiting elevation | The limiting elevation restricts the elevations of the points on the new segment. For each point on the selected segment, if the elevation of the new position for that point (after considering the surface, percentage of height to surface, and the maximum bench height) exceeds the limiting elevation, the new elevation for the point is changed so that it does not exceed the limiting elevation. |
| Horizontal direction |
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Result
The selected segment is copied and modified according the settings. The new segment is drawn in Graphics Any loops which form as a result of contracting portions of the segment are removed.
The string number of the new segment is one number above the string number of the selected segment.
Before calculating the positions of the points on the new segment, the selected segment is examined with respect to the DTM and new points are introduced where the segment is found to pass through (from above to below, or below to above) the DTM surface. This ensures that a clean transition from cut to fill is achieved especially when using the Z direction of to dtm.
