Benches

This topic relates to the Extrude outlines as mining blocks option on the Select Data screen.

The Default bench height, specified in metres, is used to determine the toe elevation of a bench according to the string position as follows:

Crest: Toe RL = String RL – Bench Ht.
Mid-Bench: Toe RL = String RL – (Bench Ht/2).
Toe: Toe RL = String RL.

If DPLUS and DMINUS are used then:

Bench ht = (DPLUS + DMINUS)/2.

Note: If you choose to perform an automatic search for bench exits, the Vertical search tolerance is considered relative to the toe reference level and is plus or minus.

The Vertical search tolerance, for the String Position options shown on the Select Data screen, using a default bench height, can be illustrated as follows:

Using a variable bench height (DPLUS and DMINUS option) can be illustrated as follows:

If a Default bench height is specified then the String Position must also be specified.
If DPLUS and DMINUS are to be used then the String Position does not need to be specified.
If DPLUS and DMINUS are to be used then the string object must have these columns and they must not contain absent values.
Alternatively, if DPLUS and DMINUS are present in the Block Reserves they can be copied to the string object by selecting Add block attribute on the Field Treatments screen.