<abstract xmlns="http://www.w3.org/1999/xhtml">Understanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of correlations between the engineering properties of intact rock has always been the scope of experimental research, driven by the need to depict the actual behaviour of rock and to calculate most accurately the design parameters. To determine the behaviour of intact rock, the value of important mechanical parameters such as Young’s modulus (<italic>E</italic>), Poisson’s ratio (ν) and the strength of rock (σcd) was calculated. Recently, for modelling the behaviour of intact rock, the crack initiation stress (σci) is another important parameter, together with the strain (σ). The ratio of Young’s modulus and the strength of rock is the modulus ratio (<italic>M</italic>R), which can be used for calculations. These parameters are extensively used in rock engineering when the deformation of different structural elements of underground storage, caverns, tunnels or mining opening must be computed. The objective of this paper is to investigate the relationship between these parameters for Hungarian granitic rock samples. To achieve this goal, the modulus ratio (<italic>M</italic>R = <italic>E</italic>/σc) of 50 granitic rocks collected from Bátaapáti radioactive waste repository was examined. Fifty high-precision uniaxial compressive tests were conducted on strong (σc >100 MPa) rock samples, exhibiting the wide range of elastic modulus (<italic>E</italic> = 57.425–88.937 GPa), uniaxial compressive strength (σc = 133.34–213.04 MPa) and Poisson’s ratio (ν = 0.18–0.32). The observed value (<italic>M</italic>R = 326–597) and mean value of <italic>M</italic>R = 439.4 are compared with the results of similar previous researches. Moreover, the statistical analysis for all studied rocks was performed and the relationshipbetween <italic>M</italic>R and other mechanical parameters such as maximum axial strain <inline-formula><alternatives><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_sgem-2019-0010_eq_001.png"></inline-graphic><math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mrow><mrow><mo>(</mo><mrow><msub><mi>ε</mi><mrow><mtext>a,</mtext><mtext> </mtext><mtext>max</mtext></mrow></msub></mrow><mo>)</mo></mrow></mrow></math><tex-math>$\left( {{\varepsilon }_{\text{a,}\,\text{max}}} \right)$</tex-math></alternatives></inline-formula>for studied rocks was discussed.</abstract>

Understanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of correlations between the engineering properties of intact rock has always been the scope of experimental research, driven by the need to depict the actual behaviour of rock and to calculate most accurately the design parameters. To determine the behaviour of intact rock, the value of important mechanical parameters such as Young’s modulus (E), Poisson’s ratio (ν) and the strength of rock (σcd) was calculated. Recently, for modelling the behaviour of intact rock, the crack initiation stress (σci) is another important parameter, together with the strain (σ). The ratio of Young’s modulus and the strength of rock is the modulus ratio (MR), which can be used for calculations. These parameters are extensively used in rock engineering when the deformation of different structural elements of underground storage, caverns, tunnels or mining opening must be computed. The objective of this paper is to investigate the relationship between these parameters for Hungarian granitic rock samples. To achieve this goal, the modulus ratio (MR = E/σc) of 50 granitic rocks collected from Bátaapáti radioactive waste repository was examined. Fifty high-precision uniaxial compressive tests were conducted on strong (σc >100 MPa) rock samples, exhibiting the wide range of elastic modulus (E = 57.425–88.937 GPa), uniaxial compressive strength (σc = 133.34–213.04 MPa) and Poisson’s ratio (ν = 0.18–0.32). The observed value (MR = 326–597) and mean value of MR = 439.4 are compared with the results of similar previous researches. Moreover, the statistical analysis for all studied rocks was performed and the relationshipbetween MR and other mechanical parameters such as maximum axial strain (εa, max)$\left( {{\varepsilon }_{\text{a,}\,\text{max}}} \right)$for studied rocks was discussed.

Complex analysis of uniaxial compressive tests of the Mórágy granitic rock formation (Hungary)

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Understanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of...

Complex analysis of uniaxial compressive tests of the Mórágy granitic rock formation (Hungary)

Article Category: Research Article

Published Online: Apr 12, 2019

Page range: 21 - 32

Received: Sep 15, 2018

Accepted: Feb 04, 2019

DOI: https://doi.org/10.2478/sgem-2019-0010

Keywords
uniaxial compressive test, modulus ratio (), maximum axial strain(ε), crack damage stress(σ), crack initiation stress (σ), Mórágy granite formation.

© 2018 M. Davarpanah et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Complex analysis of uniaxial compressive tests of the Mórágy granitic rock formation (Hungary)

Article Category: Research Article

Published Online: Apr 12, 2019

Page range: 21 - 32

Received: Sep 15, 2018

Accepted: Feb 04, 2019

DOI: https://doi.org/10.2478/sgem-2019-0010

Keywordsuniaxial compressive test, modulus ratio (), maximum axial strain(ε), crack damage stress(σ), crack initiation stress (σ), Mórágy granite formation.

© 2018 M. Davarpanah et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
uniaxial compressive test, modulus ratio (), maximum axial strain(ε), crack damage stress(σ), crack initiation stress (σ), Mórágy granite formation.