Amadei B. Rock Anisotropy and the Theory of Stress Measurements

Springer, 1983. — 497 p. — (Lecture Notes in Engineering 2). — e-ISBN13: 978-3-642-82040-3This important work by Bernard Amadei provides the solution to a problem central to interpretation of stress measurements in anisotropic rock. Although numerical methods have the capability of describing the stress and strain distributions in anisotropic bodies subjected to very general systems of loading, it is not feasible to perform a full numerical analysis for each new stress measurement configuration. In the overcoring methods of stress measurement, in which an inclusion is emplaced in a pilot borehole and then overcored with a concentric, larger borehole, the boundary conditions are sufficiently well defined and regular that a "closed-form" solution could be obtained. Previous authors have produced useful analyses of subsets of the overcoring problem in which an inclusion is emplaced in rock having either isotropic elastic properties or anisotropic properties with symmetry aligned to the boreholes. Dr. Amadei's results, on the other hand, allow the concentric boreholes to have any orientation with respect to both the initial stress field and the axes of elastic symmetry of the rock. The thickness and properties of the elastic inclusion and the system used to measure strains or displacements in the overcored inclusion, are also described with general parameters. Thus the results have real value and are a significant advance for practical rock mechanics.