Statistical characterisation of intact rock properties at a Canadian underground mining project

At the early stages of an underground mining project in the Canadian arctic, two successive field and laboratory campaigns were undertaken to evaluate intact rock properties (tensile strength and uniaxial compressive strength (UCS). All tests were performed according to the International Society for Rock Mechanics (ISRM) suggested methods. Intact rock properties were evaluated for several rock types. The obtained results were compared to target levels of confidence associated with different stages of a mining project. This was done using various statistical analysis methods. The results obtained for the different rock types are presented and discussed. A discussion is also provided on the level of confidence required for permanent versus temporary openings at underground mines. The approach can also be used as a tool to identify geotechnical drilling targets for subsequent characterisation campaigns