Authors: Stead, D; Coggan, JS; Elmo, D; Yan, M Purchase Paper |

Stead, D, Coggan, JS, Elmo, D & Yan, M 2007, 'Modelling Brittle Fracture in Rock Slopes - Experience Gained and Lessons Learned', in Y Potvin (ed.),

Modelling of rock slopes has until recently traditionally considered failure as a yield/sliding dominated process. Brittle failure of rock during the rock slope failure was generally considered either unimportant or 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 analyses incorporating discrete fracture networks. The authors emphasise that the incorporation of intact rock fracture into the analysis of rock slopes is important in many rock slopes and essential if the failure of large open pit slopes or high mountain failures is to be realistically modelled.

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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

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