Page 365 - Rock Mechanics For Underground Mining

12 Mining methods and method

selection

12.1 Mining excavations

Recoveryofmineralfromsubsurfacerockinvolvesthedevelopmentofphysicalaccess
to the mineralized zone, liberation of the ore from the enclosing host rock and transport
of this material to the mine surface. Excavations of various shapes, sizes, orientations
and functions are required to support the series of operations which comprise the
complete mining process. A schematic layout of an underground mine is shown in
Figure 12.1. Three types of excavations employed in the process are recognised in
the figure. These are the ore sources, or stopes, the stope access and service openings,
or stope development, and the permanent access and service openings. Irrespective
of the method used to mine an orebody, similarities exist between the functions and
the required geomechanical performances of the different types of non-production
excavations.
A stope is the site of ore production in an orebody. The set of stopes gener-
ated during ore extraction usually constitutes the largest excavations formed during

Figure 12.1 Basic infrastructure for
an underground mine (after Hamrin,
2001).

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