Wiles, TD 2007, 'Evidence Based Model Calibration for Reliable Predictions', in Y Potvin (ed.), Proceedings of the Fourth International Seminar on Deep and High Stress Mining
, Australian Centre for Geomechanics, Perth, pp. 3-20.
This paper discusses how to quantify the reliability of numerical model predictions, ways to improve the
reliability, and finally how to apply this knowledge. By comparing model results with actual mine response
we can quantify the reliability of numerical model predictions. This reliability can be improved by refining
our model. This may require an improved representation of the geometry, better estimates of the pre-mining
stress state, fine-tuning of the material properties and implementation of more complex plastic constitutive
response. We can readily assess how important each of these refinements is simply by seeing how much
improvement in reliability each of these refinements provides. This allows us to determine what type of
model we require and assess whether the increased cost of a more complex model can be justified. Once we
have quantified the reliability, we can use probability theory to make predictions of future mine behaviour.
The use of probabilistic prediction allows for direct cost benefit comparisons of various alternates to be
more readily considered.
Jamieson, M. (2007) Personal Communication, Senior Rock Mechanics Engineer, Xstrata Copper – Mount Isa Copper
Operations, Mt. Isa, Queensland, Australia.
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Rock. Mech. Min. Sci. Vol. 31, pp. 439-446.
Wiles, T.D. and Kaiser, P.K. (1994) In situ stress determination using the under-excavation technique – II.
Applications. Int. J. Rock. Mech. Min. Sci., Vol. 31, pp. 447-456.
Wiles, T.D., Villaescusa, E. and Windsor, C. (2004) Rock reinforcement design for overstressed rock using three-
dimensional numerical modelling. 5th International Symposium on Ground Support, Perth, Australia, 2004,
Wiles, T.D. (2005) Rockburst Prediction Using Numerical Modelling: Realistic Limits for Failure Prediction Accuracy.
6th International Symposium on Rockbursts and Seismicity in Mines (RaSiM 6), Perth, Australia, 2005,
Wiles, T.D. (2006) Reliability of Numerical Modelling Predictions, Int. J. Rock Mech. & Min. Sci. 43, pp. 454-472.
Wiles, T.D. (2007) Map3D User’s Manual, available from
Evidence Based Model Calibration for Reliable Predictions T.D. Wiles
20 Deep Mining 07, Perth, Australia