Abstract
In this paper, the method of determination the orthotropy ratio and the principal material direction of orthotropic brittle material in diametrical compression test is shown. For this method, strains and angles between principal strain and the direction of load are calculated at the center of cross section under several orthotropy ratios and several angles between direction of load and principal material direction by theoretical solution. The relation between ratio of these strains and principal material direction, and the relation between the direction of principal strain and that of principal material direction are shown by graphical representations in this paper. When strains and directions of principal strain obtained by rosette gages are applied to these graphical representations, the orthotropy ratio and the principal material direction of this specimen are able to be determined.
