3D Hydromechanical discontinuum simulation for pit slopes

Beck, D., Reusch, F., Beck Engineering, Australia

The assessment of slope stability does not frequently account for the interaction between stress, rock mass damage and water pressure and flow in a rigorous manner. Owing to improvements in computer capacity, it is now possible to undertake fully coupled or partially coupled, 3d hydromechanical Finite Element simulation of mines, including explicit representations of large numbers of discontinuities. The analysis requires fewer assumptions than uncoupled analysis or 2d analysis, but may require a change in how hydrological data is collected. The way hydrological data is incorporated in stability assessment and the approach to uncertainty in hydrological information also requires discussion.
The current procedures for this type of analysis are discussed, along with some practical difficulties and learnings from early applications. A work flow for integration of 3d hydromechanical modelling with pit planning and some considerations for the management of uncertain data are also proposed.