Forecasting potential rock slope failure in open pit mines using the inverse-velocity method / Прогнозирование потенциального разрушения откосов горных пород в карьерах открытым способом с использованием метода обратной скорости

Forecasting potential slope failure in open pit mines is necessary to maintain safety and mine productivity. Laboratory testing of rain induced landslides in Japan 20 years ago led to an inverse-velocity approach for estimating the time of slope failure. This approach appears to have been largely overlooked in mining, but has now been successfully applied, aiding in the prediction of three large slope failures ranging in size from 1 to 18 million cubic metres and control of another large instability. The predictions were forecasted five days to three months in advance of failure. This paper provides an overview of the development of inverse-velocity as a tool for failure prediction and a detailed discussion of the advantages and limitations of the technique, illustrated by examples from the literature. Four original case examples of successful application of this approach are then described. Forecasting rock slope failure is a complex problem, involving observations, analysis and experienced judgment. In many cases, the inverse-velocity method is a simple, but powerful tool aiding this process. <...>