Fabric and contact parameters for sand from wave velocity measurements

This paper aims to describe the elastic behavior of granular materials such as sand from a micromechanical point of view and in particular its anisotropic character. First an empirical description of the anisotropic elasticity in general is given (with consideration of initial and stress induced anisotropy) based on experimental observations. Then the empirical description is linked with a micromechanical approach called ''static hypothesis'' in which the basic relations are a description of the contact forces in the medium and a definition of the global strain. The last part focuses on the description of experimental results by the micromechanical approach.