Case Studies in the Assessment of Rock Mass Criteria

Various rock mass failure criteria are being validated against field performance as part of a large research program into the geotechnical risk of concrete gravity dams. The project has sought rock structures which may contribute to providing either upper or lower bounds to various failure criteria. The emphasis therefore has been on finding sites with high quality field and laboratory data. This paper summarises the analysis and results of a large pit slope at Kidston Gold Mine, together with a summary of other previously reported cases. The results from the studies allow the field stresses and strengths to be compared with the commonly used Hoek-Brown empirical rock mass failure criterion. As expected, the bounds on the various failure criteria are very broad and care must be taken when placing any reliance on any particular criterion.