Identification of higher symmetry in triclinic stiffness tensor: Application to high pressure dependence of elastic anisotropy in deep underground structures

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F22%3A00562004" target="_blank" >RIV/67985530:_____/22:00562004 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985831:_____/22:00561120 RIV/68145535:_____/22:00561120

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S1365160922001344" target="_blank" >https://www.sciencedirect.com/science/article/pii/S1365160922001344</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijrmms.2022.105168" target="_blank" >10.1016/j.ijrmms.2022.105168</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Identification of higher symmetry in triclinic stiffness tensor: Application to high pressure dependence of elastic anisotropy in deep underground structures

Popis výsledku v původním jazyce

We present an approach of identifying anisotropy axes and the type of symmetry from ultrasonic measurements of 21 elastic constants of the complete stiffness tensor characterizing anisotropic materials. The approach is applied to examine anisotropic elasticity of two crystalline rock samples from two underground research labo-ratories: (1) the migmatized gneiss from Bukov in the Czech Republic and (2) the Aare Granite from Grimsel in Switzerland. The full stiffness matrix is measured at selected pressure levels from 0.1 to 100 MPa. We demon-strate that the Bukov migmatized gneiss is orthorhombic, whereas the Grimsel granite is transversely isotropic under atmospheric pressure. The degree of anisotropy of both rocks decreases with applied confining pressure due to closing of preferentially oriented cracks. While the Grimsel granite is very sensitive to pressure and be-comes almost isotropic at high pressures, a great portion of anisotropy in the Bukov migmatized gneiss remains even under high pressures due to its texture. The dependence of Young's and shear moduli with pressure em-phasizes the importance of taking the pressure into account for underground projects.

Název v anglickém jazyce

Identification of higher symmetry in triclinic stiffness tensor: Application to high pressure dependence of elastic anisotropy in deep underground structures

Popis výsledku anglicky

We present an approach of identifying anisotropy axes and the type of symmetry from ultrasonic measurements of 21 elastic constants of the complete stiffness tensor characterizing anisotropic materials. The approach is applied to examine anisotropic elasticity of two crystalline rock samples from two underground research labo-ratories: (1) the migmatized gneiss from Bukov in the Czech Republic and (2) the Aare Granite from Grimsel in Switzerland. The full stiffness matrix is measured at selected pressure levels from 0.1 to 100 MPa. We demon-strate that the Bukov migmatized gneiss is orthorhombic, whereas the Grimsel granite is transversely isotropic under atmospheric pressure. The degree of anisotropy of both rocks decreases with applied confining pressure due to closing of preferentially oriented cracks. While the Grimsel granite is very sensitive to pressure and be-comes almost isotropic at high pressures, a great portion of anisotropy in the Bukov migmatized gneiss remains even under high pressures due to its texture. The dependence of Young's and shear moduli with pressure em-phasizes the importance of taking the pressure into account for underground projects.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10507 - Volcanology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

International Journal of Rock Mechanics and Mining Sciences

ISSN

1365-1609

e-ISSN

1873-4545

Svazek periodika

158

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

16

Strana od-do

105168

Kód UT WoS článku

000855044200002

EID výsledku v databázi Scopus

2-s2.0-85137050557