ABSTRACT
Estimation of the magnitudes and orientations of the natural in situ rock stress at a particular project site is not always an easy task: the regional stress state can be locally perturbed by geological discontinuities, inhomogeneities and anisotropies. Also, there is a variety of difficulties associated with the various stress measurement techniques. In order to provide guidance on this subject, the ISRM Commission on Testing Methods has recently completed four new Suggested Methods for rock stress estimation. These have been published in 2003 in a Special Double Issue of the International Journal of Rock Mechanics and Mining Sciences, Vol. 40, Issues 7/8, together with seventeen supporting papers – all illustrating various aspects of rock stress estimation. In the current paper, the content of the ISRM Suggested Methods and the supporting papers is summarized within the thematic context of this Sigma3 Symposium and the need to carefully consider the strategy and tactics of a rock stress estimation campaign.
