Abstract
Deformation characteristics of rock masses are often significantly anisotropic due to discontinuities e.g. sedimentary planes and joints. Anisotropic properties of rock masses are commonly obtained by several triaxial tests using rock cores sampled to different orientations, but which is costly and time consuming. In this study in-situ torsional shear test for rock masses is proposed by the authors. Anisotropic deformation properties can be obtained by fewer tests than the conventional testing method. In this paper, for developing testing methods, a method of determining constitutive parameters for transversely isotropic rock masses is proposed. In this proposed method, the directions of anisotropy are determined by the strain responses under isotropic consolidation and 5 elastic parameters of transversely isotropic rocks are determined by both strain responses during isotropic consolidation and the distributed stress responses during torsional shearing.
