INFLUENCE OF SCALE EFFECT AND HETEROGENEITY OF ROCKS TO DETERMINE THEIR STRENGTH PROPERTIES

The analysis and considers some aspects of the existence of a scale effect when testing rock samples to determine their strength properties. It is noted that in addition to determining the average values of strength important information is the value of the coefficient of variation as a characteristic of heterogeneity of rocks. The results of experimental studies of rock samples of different sizes when determining the ultimate strength in tension. According to test results there has been a sustained change (reduction) characteristics of the dispersion when increasing the length of the samples with an insignificant reduction of the value of the average strength. For samples of marble and Sandstone, medium strength with a change in the size of the samples practically stays constant. Developed methodology and conducted strength tests of samples of small dimensions, whose diameter was ~6 mm. In specimens of small size, it should be noted a slight dispersion of values of indicators of the strength properties and consequently small values of the coefficient of variation. The data obtained during testing samples of small sizes of the studied rocks is quite associated with allowance for the size effect data for tests on standard samples, indicating the possibility of using this method for determining strength and elastic properties of rocks.

The study has partly been supported by the Russian Science Foundation, Grant No. 151910007, ZDV and PPE, and by the Russian Foundation for Basic Research, Grant No. 140500446).

Keywords

Rock, destruction, scale effect, experiment, durability, heterogeneity, structure, size.

Issue number: 11
Year: 2016
ISBN:
UDK: 622.02
DOI:
Authors: Zaytsev D. V., Kochanov A. N., Toktogulov Sh. Zh., Panteleev I. A., Panfilov P. E.

About authors: Zaytsev D.V., Candidate of Physical and Mathematical Sciences, Senior Researcher, e-mail: dmitry.zaytsev@urfu.ru, Ural Federal University, 620002, Ekaterinburg, Russia, Kochanov A.N., Candidate of Technical Sciences, Senior Researcher, Institute of Problems of Comprehensive Exploitation of Mineral Resources of Russian Academy of Sciences, 111020, Moscow, Russia, e-mail: kochanov@mail.ru, Toktogulov Sh.Zh., Student, e-mail: toksham@mail.ru, Ural Federal University, 620002, Ekaterinburg, Russia, Panteleev I.A., Candidate of Physical and Mathematical Sciences, Researcher, Institute of Continuous Media Mechanics of Ural Branch of Russian Academy of Sciences, Perm, Russia, e-mail: pia@icmm.ru, Panfilov P.E., Doctor of Physical and Mathematical Sciences, Professor, e-mail: peter.panfilov@urfu.ru, Ural Federal University, 620002, Ekaterinburg, Russia.

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