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PILLAR SUPPORTED MINING METHODS
Figure 13.28 Pillar performance,
defined by degree of rupture (over-
break) and mechanical integrity, com-
pared with domains defined by rock
degradation and failure criteria (after
Diederichs et al., 2002).
13.7.2 Extraction sequence
Whatever the expected intermediate and final states of stress in a mining layout,
the planning requirement is to develop a sequence in which stopes are to be mined,
and perhaps pillars are to be recovered, which satisfies geomechanical constraints
and specific mining requirements, such as production rate, number of sources of ore
in operation at any one time, and a tolerable level of risk to ore reserves. When
the integrity and stability of the final mine layout are not assured, the question of
extraction sequence becomes acute. Some general principles are now proposed to
guide formulation of a logical order for stope and pillar extraction.
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