Simulating a mining-triggered rock avalanche using DDA: A case study in Nattai North, Australia

This study numerically simulated the failure process of a mining-induced landslide at Nattai North, Australia. Results obtained using Discontinuous Deformation Analysis (DDA) matched the conceptual failure process suggested by local geologists and the observed maximum run-out distance. The maximum velocity of the sliding rocks exceeded 40 m/s. Computational results showed that the slope with inward sub-horizontal bedding planes and sub-vertical discontinuities remained stable if the mining-induced high principle stresses did not fracture the rocks near the slope toe. Failure of the rocks near the toe of the slope was a key causal factor in the subsequent landslide. This paper presents the first numerical simulation of the post-failure behavior of the mining-induced landslide at the Nattai North site. It also represents the first DDA simulation to clarify the chain reaction of a mining-induced landslide and demonstrate its applicability in such investigations.