Study on Poisson’s Ratio Anisotropy of Foliated Metamorphic Rocks of Central Nepal
DOI:
https://doi.org/10.64862/Keywords:
Poisson’s ratio, Anisotropy, Foliated rockAbstract
Poisson’s ratio, defined as the negative ratio of transverse to axial strain under uniaxial stress, quantifies the lateral deformation behavior of materials and is crucial for analytical and numerical modeling in engineering. In metamorphic rocks, Poisson’s ratio exhibits strong anisotropy due to foliation orientation related to applied axial stress. This study experimentally investigates the Poisson’s ratios of fine-grained slate, medium-grained metasandstone, and coarse-grained Higher Himalayan banded gneiss from the Lesser Himalaya, Central Nepal. A total of 157 specimens, cored at varying angles to foliation planes, were tested under uniaxial compression. Results reveal orientation-dependent maxima and minima in Poisson’s ratio, controlled by foliation, grain size, and mineral composition.
References
ASTM International. (2015). ASTM D7012-14ε1: Standard test methods for compressive strength and elastic moduli of intact rock core specimens under varying states of stress and temperatures. ASTM International.
Cho, J. W., Lee, S. K., Jeon, S., and Min, K. B. (2012). Deformation and strength anisotropy of Asan gneiss, Boryeong shale, and Yeoncheon schist. International Journal of Rock Mechanics and Mining Sciences, 50, 158–169.
Christensen, N. I. (1966). Elasticity of ultrabasic rocks. Journal of Geophysical Research, 71 (24), 5921–5931. https://doi.org/10.1029/JZ071i024p05921
Gercek, H. (2007). Poisson’s ratio values for rocks. International Journal of Rock Mechanics and Mining Sciences, 44, 1–13. https://doi.org/10.1016/j.ijrmms.2006.04.011
Kim, H., Cho, J. W., Song, I., and Min, K. B. (2012). Anisotropy of elastic moduli, P-wave velocities, and thermal conductivities of Asan gneiss, Boryeong shale, and Yeoncheon schist in Korea. Engineering Geology, 147, 68–77. https://doi.org/10.1016/j.enggeo.2012.07.015
Poisson, S. D. (1829). Mémoire sur l’équilibre et le mouvement des corps élastiques. Mémoires de l’Académie Royale des Sciences de l’Institut de France, 8, 357–570, 623–627.
Saeidi, O., Rasouli, V., Vaneghi, R. G., Gholami, R., and Torabi, S. R. (2014). A modified failure criterion for transversely isotropic rocks. Geoscience Frontiers, 5 (2), 215–225. https://doi.org/10.1016/j.gsf.2013.05.005
Timoshenko, S. P., and Goodier, J. N. (1970). Theory of elasticity (3rd ed.). McGraw-Hill.
Wang, Q., and Ji, S. (2009). Poisson’s ratio of crystalline rocks as a function of hydrostatic confining pressure. Journal of Geophysical Research: Solid Earth, 114, B09202. https://doi.org/10.1029/2008JB006167
Wu, R., Li, H., Li, X., Xia, X., and Liu, L. (2020). Experimental study and numerical simulation of the dynamic behavior of transversely isotropic phyllite. International Journal of Geomechanics, 20 (8), 04020105. https://doi.org/10.1061/(ASCE)GM.1943-5622.0001737
Zhang, X. P., Wong, L. N. Y., Wang, S. J., and Han, G. Y. (2011). Engineering properties of quartz mica schist. Engineering Geology, 121 (3–4), 135–149. https://doi.org/10.1016/j.enggeo.2011.04.020
Downloads
Published
Issue
Section
License
Copyright (c) 2025 Nepal Society of Engineering Geology (NSEG)
This work is licensed under a Creative Commons Attribution 4.0 International License.
