A preliminary, calibrated scheme for estimating rock mass properties

D.A. Beck and C.R. Lilley
Beck Engineering Pty Ltd, Sydney, Australia

F. Reusch, V. Levkovitch, G. Putzar and A. Flatten
Beck Engineering Pty Ltd, Berlin, Germany

Calibration of 3D, discontinuum, strain softening, dilatant (SSD) models of mines often yields different rock mass scale (representative elementary volume, or REV) properties to empirical methods. In this paper, some steps towards a calibrated empirical scheme for estimating material properties for some types of 3d, discontinuum non-linear models targeting larger than (REV) scale phenomena are described. The scheme uses typical pre-mining rock mass classification date and strength tests to estimate the peak and residual yield, softening and dilatancy parameters. The scheme is a purely empirical device, derived from UCS and GSI field data and calibrated model results, and is a work in progress. The underlying nature of the Hoek Brown-GSI scheme (Hoek, E., and E. T. Brown., 1997; Hoek et al., 2002), is validated by the work.