Constraints

Source file: strategy-setups-constraints.htm

Constraints in Strategy provide you with the ability to refine or limit a schedule based on given values. Constraints are categorised as hard Evolution must obey this constraint when generating a schedule. or soft Evolution attempts to satisfy this constraint when generating a schedule but it is not forced. in Evolution. You can then verify the schedule results by following the steps in Pivot Reporting.

The following constraints are available:

Constraint Hard/Soft Description
Global Accumulation

H (upper limit)

S (lower limit)

Used to specify a minimum or maximum constraint for any item in the model, on a period by period basis.
Ore Exposure S Used to ensure that there is enough ore supply in the benches below the mining areas.
Pit Accumulation H Used to specify a maximum accumulation value for a given model on a period by period basis.
Process Accumulation H Used to specify a range of accumulation values for any item in the model, on a process by period basis.
Process Blend S Allows you to optimise the blend as part of the value maximisation process.
Sink Rate H The mining duration per bench. Calculated from the total tonnes available for mining on a bench and the corresponding dig rate.
Stage Accumulation H Used to specify a maximum constraint for any item in the model, on a stage by period basis.
Stage Availability H Allows you to flag the availability of pit stages per period.
Stage Bench Turnover H Used to specify the maximum number of benches allowed per stage in a schedule period.
Stage Dependency H Used to define the stage release strategy to be applied, and precedence order in which the pit stages are available.
Stage Sink Rate H The mining duration per stage.
Stockpile Availability H Allows you to set the periods in which material can be sent to or reclaimed from a stockpile.
Waste Dump Availability H Allows you to set the periods in which a waste dump can be used.