Using DFN Logic in Open Pit Stability Analysis: Applications for Calibration and Predictive Calculation Including Defined Persistence Discontinuities

Authors

Edgar MontielEsteban Hormazabal

Emilia Rubio

Max Blondel

Jonathan Soberanis

In open pit stability analyses, numerical modeling helps to evaluate failure modes related to the interaction between discontinuities and the rock mass. In particular, numerical models that integrate discrete fracture networks (DFNs) are a relevant tool for detecting slope failure mechanisms, especially when failure involves slippage along geological structures.  Traditionally, the focus of such analyses is stochastic in nature. However, a deterministic approach to open pit modeling can be adopted using DFN as a discontinuity integration logic with defined persistence based on field mapping.

This article presents a stability analysis of a "deterministic" type approach which implements the DFN logic incorporated in discrete element software, which would allow for the representation of discontinuities of variable persistence. The methodology has been validated through its application in numerical open pit models aimed at calibrating instabilities and evaluating predictive design conditions, whose results have been satisfactory, and representative of the instability conditions observed in situ.