Using Smart Pits in Optimization
Updated October 19, 2017
This article applies to:
- Softree Optimal
Softree Optimal can also decide which pit should be used if there is a choice.
- Open the Softree Optimal application.
- File | Open. Select Hart Rd optimal haul.dsnx. Press Open.
- Maximize the Profile window, ensure the Alignment Properties panel is visible.
At this point, Pit-1 is being used for all waste as there are no alternatives.
Figure 1: Waste pit usage at station 0.0 only.
- Add variable waste pits at stations 500 and 900:
- Make sure that V-align 1 is selected.
- Press the Options button and select the Pits tab.
- Press the Add button in the Pits dialogue box.
- Enter station 500 in the Pit Access Station dialogue box, press OK to accept and close.
- Make sure that Waste and Variable volume are set (figure below).
- Repeat to create another variable waste pit at station 900.
Figure 2: New waste pits added.
Notice that the Waste quality is Q1 (worst); this means that any material can be accepted by this pit. Capacity is set to inf (infinite); you can optionally limit the size of the pit by setting this property. Site preparation cost is set to zero by default.
- Press OK to close the options dialogue box.
Figure 3: Recalculate Range dialogue box with the Re-Cost option set.
- Set the Re-Cost^ check box when prompted with the Recalculate Range dialogue box.
- Press OK to recalculate and update the Optimal Haul.
Figure 4: Waste pit usage at stations 500 and 900.
Our new pits are both being used and Pit 1 at station 0 pit is not; this reduces the haul cost.
Now let’s add site preparation cost and see how the optimal haul calculation is impacted.
- Press the Options button. Select the Pits tab.
- Select Pit 4: waste variable, enter 10,000 as the site preparation $.
- Enter the same site preparation $ for Pit 1 and Pit 5.
- Press OK to accept the change as shown in the figure below:
Figure 5: Adding Site Preparation Cost
- When prompted to Recalculate Range, select OK.
Notice that the only waste pit being used now is the one at station 900; the optimal haul calculation has determined that, in this case, the extra hauling cost is less than the Site preparation cost of opening two pits.
Figure 6: Updated Opti-Haul Showing Pit Usage
- File | Exit. Do not save changes.