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, Australian Centre for Geomechanics, Perth, pp. 213-223, https://doi.org/10.36487/ACG_repo/708_11
The mechanism of composite deformation in open pit coal mine slopes combines slip along existing defects
with strength mobilisation involving rock material. Mining activity and initial stress conditions are linked
with the onset of relatively sudden, unpredicted failures. In order to develop more reliable methods for
recognising potential failure and providing early warning signs, it is first necessary to identify and
understand the potential trigger processes. This paper describes early progress in numerical modelling of
bedded coal measures rock masses under conditions where composite slope failures have occurred
repeatedly. Results to date illustrate the effects of initial stress on extensional deformations within a highwall
slope. The results are linked to observations of actual failures, and highlight the role of extension strain
fracturing near the slope toe as a triggering mechanism.
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Numerical Modelling of Rock Slope
Slope Stability 2007, Perth, Australia 223