Abstract:Uniaxial tension tests were conducted on specimens with three axial orientations taken from the same block sample of Inada granite for investigating anisotropy of strength and deformation. The experimental results reveal that the tensile strength and deformation properties of the Inada granite vary with the direction of tensile load. The strength and Young¢s modulus in the R-direction,perpendicular to the rift plane,are significantly less than those in other directions. In addition,the degree of anisotropy of tensile strength is largest compared with that of other physical properties. Moreover,a new type of specimen assembly is designed so that microscopic observations of fracture at different stages of the tensile failure process can be performed. Specimens before completely broken are successfully obtained,making such microscopic observation possible. The observed tensile fracture in a specimen examined at a stage beyond ultimate strength but before completely broken shows that the tensile fracture path is mostly within mineral grains in the granite.