Stripping Schedule

Apply prestripped waste credit sequentially to fixed ore/stripping schedule and screen capacities; does not optimize precedences or silently reschedule.

Description

A stripping schedule allocates required waste removal across periods.

A stripping schedule allocates required waste removal across periods. Existing prestripping credit reduces new waste before comparing material movement with capacity.

The tool returns newWasteTonnesByPeriod (new waste tonnes by period); totalMaterialTonnesByPeriod (total material tonnes by period); capacityMarginsTonnesByPeriod (capacity margins tonnes by period); allPeriodsWithinCapacity (all periods within capacity). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.

When to use Stripping Schedule

Use Stripping Schedule when you already have oreTonnesByPeriod, requiredWasteOreRatios, prestrippedWasteCreditTonnes, totalMaterialCapacityTonnesByPeriod and want newWasteTonnesByPeriod, totalMaterialTonnesByPeriod, capacityMarginsTonnesByPeriod, allPeriodsWithinCapacity. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.

How to use Stripping Schedule and understand its results

Enter oreTonnesByPeriod, requiredWasteOreRatios, prestrippedWasteCreditTonnes, totalMaterialCapacityTonnesByPeriod using the field table below. Match the units, ordering and data boundaries described in the calculation.
Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
Read newWasteTonnesByPeriod, totalMaterialTonnesByPeriod, capacityMarginsTonnesByPeriod, allPeriodsWithinCapacity. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.

Input field	Meaning	Value type and bounds	Requirement
oreTonnesByPeriod	Ore tonnes by period	list of number	Required
requiredWasteOreRatios	Required waste ore ratios	list of number	Required
prestrippedWasteCreditTonnes	Prestripped waste credit tonnes	number	Required
totalMaterialCapacityTonnesByPeriod	Total material capacity tonnes by period	list of number	Required

Use aligned nonnegative period inputs. Consume credit sequentially, carry unused credit forward and compare ore plus new waste with period capacity; zero margin passes.

requiredWaste = ore×ratio; newWaste = requiredWaste−min(credit,requiredWaste)

The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.

json

{
  "input": {
    "oreTonnesByPeriod": [
      100,
      100
    ],
    "requiredWasteOreRatios": [
      2,
      3
    ],
    "prestrippedWasteCreditTonnes": 50,
    "totalMaterialCapacityTonnesByPeriod": [
      300,
      350
    ]
  },
  "output": {
    "newWasteTonnesByPeriod": [
      150,
      300
    ],
    "totalMaterialTonnesByPeriod": [
      250,
      400
    ],
    "capacityMarginsTonnesByPeriod": [
      50,
      -50
    ],
    "allPeriodsWithinCapacity": false
  }
}

Limitations and assumptions

This implements the supplied period order and ratios. It does not optimize the schedule or validate spatial access and precedences.

Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.

Alternative or Complementary methods

Stripping Ratio: Aggregate bank-volume stripping quantities and distinguish waste/ore volume and mass ratios using supplied densities; excludes loose-volume swell. Ultimate Pit Stripping Ratio: Compare cumulative/incremental stripping across nested shells; limits do not solve ultimate-pit optimization or establish slope feasibility.

Methodological background: Surface Mining Technology: stripping ratios and pit layouts.^[1]

References

Surface Mining Technology: stripping ratios and pit layouts — NPTEL, Indian Institute of Technology Kharagpur

Similar or alternative tools

Stripping Ratio
Aggregate bank-volume stripping quantities and distinguish waste/ore volume and mass ratios using supplied densities; excludes loose-volume swell.
Ultimate Pit Stripping Ratio
Compare cumulative/incremental stripping across nested shells; limits do not solve ultimate-pit optimization or establish slope feasibility.