Shape-anisotropy Type of Young’s Modulus for Transverse Isotropic Rocks Regarding the Orientation of Foliation Plane

Abstract

Abstract: Generally, engineers need to know how rocks deform when subject to the various loads associated with engineering structures. Hence, deformability of anisotropic rocks is essential for design purposes. However, intact rock deformability depends on the orientation of the applied load. This study carried out to assess the curve-type elastic modulus anisotropy of banded amphibolite rocksas a function of foliation plane angle (B = 0°, 30°, 60° and9O°). The unconfined compressive test was performed on drilled rock samples and the values of elastic modulus are calculated. The results obtained have shown that Young modulus values of amphibolite rocks with B follow both types of shape anisotropy, “U-shape” and “decreased order-shaped”. However ,there is no clear dependence on microstructures characteristics of subtype-amphibolite rocks that controlling modulus “shape- anisotropy”.lt seems that this is mainly due to slight undulation of foliation planes, that being not perfectly straight. Thus, this study recommended further research could he undertaken regarding the role of modulus “shape-anisotropy” within the same litho-type.