Determining the type of initial anisotropy of elastic material from a series of experiments

An experimental program has been developed to identify the type of initial elastic anisotropy of the material. The program includes a series of compression experiments to determine the orientation of the principal axes of anisotropy of the material and additional experiments to find the orientation of the canonical axes of anisotropy. In order to distinguish isotropic and cubic materials, it is necessary to fulfill an experiment on biaxial tension-compression in the direction of two canonical axes of anisotropy, and a shear experiment in the same plane. Similar experiments make it possible to identify trigonal, tetragonal and hexagonal materials. To identify triclinic, monoclinic, and rhombic materials, three shear experiments in planes determined by the canonical axes of anisotropy are required.