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Abstract

Several operations are considering the transition from surface mining to underground block caving to access deeper resources. Depending on the geometry of the orebody, the undercut may be positioned beneath the foot of a large open pit slope, or behind its crest. The latter scenario also arises where a natural rock slope is present. Results are reported here from a numerical modelling study investigating the mechanics of deep-seated slope displacements in response to caving. Different failure models are investigated as a function of the orientation of the jointing pattern relative to the location and progressive development of the block cave. A 2-D discontinuum modelling approach is utilised based on the distinct-element method. The results show that the cave location and the resultant strain field, plays a significant role in the rock mass interactions that develop and the subsequent kinematic response of the slope with respect to translational, rotational and toppling behaviour.

Keywords

Distinct-element method Block caving Pit slope interaction Numerical modelling Slope deformation kinematics Rock slope instability

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Interaction between block caving and rock slope deformation kinematics as a function of cave position and orientation of discontinuities

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