Size Control

To access this screen:

Optimization control bar >> Pushbacks >> Settings and select the Size Control tab.

Define size control variables and parameters to constrain pushback generation, on a per-pushback basis. The parameters defined here apply to individual pushbacks unless stated otherwise.

Note: If a pushback is not listed in the table on this screen, the parameters of the nearest preceding pushback are used.

Pushback size control is achieved by entering values into the table. For each pushback define one or more of the following parameters:

Pushback	The pushback serial number, for example, 1.
Control	Select the size control variable from a list of previously defined variables. Click Edit Control Variables to review and add available items. See Define Control Variables.
Value	Enter the maximum size in terms of the selected control variable; for example, 500,000 (tons). A pushback's size must be defined before pushbacks can be generated so it is important that at least one Value is defined. If you attempt to generate pushbacks with no Value entries in the table, pushback generation will fail (you are told why). Note: This is not a hard constraint: The actual pushback size may exceed this value in order to satisfy other requirements
Bench Limit	Set the pushback depth limit in terms of benches; see bench elevations below the table for reference.
Adjustments	Select a previously defined pushback adjustment object. These objects are either created as the result of importing boundary data or manually digitizing a boundary and applying it to a section view, using the Apply Digitizer Boundary screen. When a pushback boundary is generated by either of these methods, they become available for selection. Pushback boundaries support an important attribute that determines how the boundary is treated (the pit shell cannot extend beyond the selected bench, the pushback cannot extend beyond this bench and so on.) See Digitized Pushback Boundary Parameters.
Mining Width	Define the mining width constraint for the pushback. Note: You can also define a global mining width constraint using the All Pit Options screen. If a pushback-level width is specified, it takes precedent over the global value.

Note: The Value and Adjustment fields work together; for example, if the pushback boundary adjustment is set to the PB Forced Limit option on the Apply Digitizer Boundary screen, and a value of 100,000,000 tonnes of rock mass is set as the Value, if the boundary adjustment includes less than 100,000,000 tonnes, the actual rock mass value defined by the boundary adjustment will be used, overriding whatever Value is defined here.