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Modelling of rock slopes has until recently traditionally considered failure as a yield/sliding dominated
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too difficult to model. The authors present a review of brittle rock fracture simulation in rock slope failure
and discuss the approaches adopted to-date. Particular emphasis is given to the application of a hybrid
finite-discrete element code incorporating fracture mechanics criteria. Simon Fraser University and
Camborne School of Mines using this approach have almost fifteen years combined experience in simulating
brittle rock fracture during rock slope failure including a wide variety of failure mechanisms. Initial
modelling focused on back analysis of both major natural rock slides and engineered slopes. The rock slopes
were modelled from an equivalent continuum to a rock debris pile. In the second phase of modelling an
equivalent continuum was assumed and a total slope analysis simulated including development of the failure
surface, brittle fracture of the rock mass and debris transport. The authors then considered the importance
of limited discontinuity persistence and step-path failure involving intact rock fracture through rock bridges.
Discrete pre-existing fractures of varied persistence were initially assumed with more recent rock slope
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Modelling Brittle Fracture in Rock Slopes — Experience Gained and Lessons Learned D. Stead, et al.
252 Slope Stability 2007, Perth, Australia