A compressive strength criterion for anisotropic rock materials

Abstract

This paper proposes a general compressive strength criterion for anisotropic rock materials under multiaxial states of stress. The proposed criterion is a generalization of the Von Mises' criterion for yielding of ductile metals, which has also been used previously as a strength criterion for brittle fracture in the spirit of both being limits of linear elastic behavior. The presently proposed criterion takes into consideration the effects of the confining pressure, the various stress components, and the material anisotropy on rock material failure in a multiaxial stress state. To verify the applicability of the proposed criterion, it has been used to construct the failure envelopes for several types of rock materials. Consequently, the constructed failure envelopes and the corresponding experimental results have been compared. In all cases, a close agreement with the experimental results has been achieved. This result demonstrates the versatility and applicability of the proposed strength criterion in representing the compressive strength behavior of anisotropic rock materials under complex multiaxial states of stress. Key words: strength, rock materials, anisotropy.