Suggested Methods for Rock Failure Criteria: General Introduction

Excerpt

In the application of rock mechanics to rock engineering design, one of the most important issues is the failure of rock: we wish to fail the rock during the excavation process; and then avoid failure of the completed structure. For this reason, the failure of rock has been one of the most important research subjects since the formation of the ISRM in 1962. However, over the years it has become difficult to decide on the best failure criterion to use in specific situations. The ‘Mohr–Coulomb’ and ‘Hoek–Brown’ are the most frequently used failure criteria—but both of these incorporate only the major and minor principal stresses, and not the intermediate principal stress. However, other criteria have been suggested over the years. The ISRM Commission on Testing Methods set out to prepare this document to provide guidance on the characteristics of the several existing failure criteria and suggest circumstances when they should be employed. …