Page 34 - Rock Mechanics For Underground Mining

ROCK MECHANICS AND MINING ENGINEERING

geomechanical parameters determining the deformational response of the medium.
Particularly valuable data are generated by the analysis of local failures in the system.
These provide information about the orientations, and possibly relative magnitudes
of the in situ field stresses, as well as high quality information on the in situ rock mass
strength parameters. Subsequently, stope mechanical and production performance
data can be assessed with a view to formulating detailed stope design and operat-
ing criteria. This might involve establishment of rules specifying, for example, stope
shape relative to geological structure, stope blasting practice, and drawpoint layouts
and designs for various types of structural and lithological conditions.
Figure 1.7 indicates that data generated by retrospective analysis are used to update
the site characterisation data, mine model and design process, via the iterative loop.
This procedure represents no more than a logical formalisation of the observational
principle long used in soil mechanics practice (Peck, 1969). It is a natural engineer-
ing response to the problems posed by basic limitations in site characterisation and
conceptualisation associated with excavation design in geologic media.

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