Author:
Name & Surname: Suknev S. V.
Company: Institute of Mining of the North, Siberian Branch, Russian Academy of Sciences (Yakutsk, Russia)
Work Position: Head of laboratory
Scientific Degree: Doctor of Engineering
Contacts: suknyov@igds.ysn.ru

The author describes general principles and application of the internal standard developed for estimating elastic properties of rocks under uniaxial compression of prismatic specimens. The standard has been developed based on an original procedure that enables determination of static elastic properties (modulus of elasticity, Poisson’s ratio) under variation of temperature in a specimen, which is neglected by the effective Russian and international standards but is of critical importance in mine construction in permafrost zone. The testing includes multiple loading of a specimen within the range of low reversible strains, which enables highly accurate and physically correct measurement of temperature and estimation of temperature effect on change in properties of the specimen passing from thawed to frozen state. The developed standard has been applied to investigation of elastic properties of enclosing rocks at diamond deposits in Yakutia. The uniaxial compression tests involved specimens of rocks (limestone, siltstone) in air-dried and water-saturated condition. A specimen was necessarily pre-compacted (2 loading cycles), and axial and transverse deformations were measured in the later-on cycles of loading. The upper and lower limits of loading were set based on the conditions of reversibility and linearity of deformation. Small deformations were measured using precision direct sensors. A specimen with sensors attached to it was placed in a temperature cell and tested sequentially under room temperature and, then, under 0 °С, –20 °С and –40 °С. It has been found that as the temperature is lowered, the elasticity modulus of the specimen linearly grows and Poisson’s ratio remains unaltered. The water-saturated specimens behave the same way. As compared to an air-dried specimen, the elasticity modulus of a water-saturated specimen decreases by 22–28% while Poisson’s ratio increases by 20–24%.

This work was supported by the Siberian Branch of the Russian Academy of Sciences, project no. VIII.74.5.1, and by the Russian Foundation for Basic Research, project no. 15-45-05014.

1. GOST 28985-91. Porody gornye. Metod opredeleniya deformatsionnykh kharakteristik pri odnoosnom szhatii (State Standard 28985-91. Rocks. Method of definition of deformational characteristics during one-axial compression). Moscow : Publishing House of Standards, 2004. 11 p. (in Russian).
2. Martin C. D., Chandler N. A. The progressive fracture of Lac du Bonnet granite. International Journal of Rock Mechanics and Mining Sciences & Geomechemical Abstracts. 1994. Vol. 31, No. 6. pp. 643–659.
3. Eberhardt E., Stead D., Stimpson B., Read R. S. Identifying crack initiation and propogation tresholds in brittle rock. Canadian Geotechnical Journal. 1998. Vol. 35, No. 2. pp. 222–233.
4. Hakala M., Kuula H., Hudson J. A. Estimating the transversely isotropic elastic intact rock properties for in situ stress measurement data reduction: A case study of the Olkiluoto mica gneiss, Finland. International Journal of Rock Mechanics and Mining Sciences. 2007. Vol. 44, No. 1. pp. 14–46.
5. Suknev S. V., Fedorov S. P. Standartnye metody opredeleniya uprugikh svoystv gornykh porod (Standard methods of definition of elastic characteristics of rocks). Gornyy Informatsionno-Analiticheskiy Byulleten = Mining Informational and Analytical Bulletin. 2012. No. 12. pp. 17–21.
6. DIN EN 14580. Prüfverfahren für Naturstein – Bestimmung des statischen Elastizitätsmoduls. Berlin : Deutsches Institut für Normung e.V., 2005.
7. Suknev S. V. Ispolzovanie okruzhnykh i diametralnykh datchikov deformatsiy dlya opredeleniya koeffitsienta Puassona pri szhatii (Use of peripheral and diametrical sensors of deformations for definition of Poisson's ratio in the time of compressing). Gornyy Informatsionno-Analiticheskiy Byulleten = Mining Informational and Analytical Bulletin. 2012. No. 12. pp. 22–27.
8. GOST R 1.0-2004. Standartizatsiya v Rossiyskoy Federatsii. Osnovnye polozheniya (State standard R 1.0-2004. Standardization in Russian Federation. Basic regulations). Moscow : Standardinform, 2007. 12 p. (in Russian)
9. GOST R 1.4-2004. Standartizatsiya v Rossiyskoy Federatsii. Standarty organizatsiy. Obshchie polozheniya (Sate Standard R 1.4-2004. Standardization in Russian Federation. Organization standards. Basic regulations). Moscow : Standardinform, 2007. 8 p. (in Russian).
10. GOST R 1.5-2004. Standartizatsiya v Rossiyskoy Federatsii. Standarty natsionalnye Rossiyskoy Federatsii. Pravila postroeniya, izlozheniya, oformleniya i oboznacheniya (State Standard R 1.5-2004. Standardization in Russian Federation. National standards of Russian Federation. Rules of formation, statement, design and definition). Moscow : Standardinform, 2007. 35 p. (in Russian).
11. Suknev S. V. Ispolzovanie datchikov deformatsiy firmy Toni Technik dlya opredeleniya koeffitsienta Puassona pri szhatii (Use of deformation sensors Toni Technik for definition of Poisson's ratio in the time of compression). Gornyy Informatsionno-Analiticheskiy Byulleten = Mining Informational and Analytical Bulletin. 2013. No. 8. pp. 97–100.
12. GOST 21153.2-84. Porody gornye. Metody opredeleniya predela prochnosti pri odnoosnom szhatii (State Standard 21153.2-84. Rocks. Methods of definition of durability limit in the time of one-axial compression). Moscow : Publishing House of Standards, 2001. 8 p. (in Russian).