Regular patterns of acoustic activity, axial and volumetric strains in rock salt under Karman’s loads and thermal effects

Authors: Kravchenko O S

Synchronous measurements of acoustic emission and deformation were carried out on rock salt samples subjected to complex stress under three different levels of the external thermal forces. The measurement instrumentation and procedures are described. The features of acoustic emission are revealed for each deformation stage and specific temperature. It is found that in the tests according to Karman’s scheme, the acoustic activity at each deformation stage changes more orderly than under uniaxial loading, which is connected with structural consolidation of the geomaterial. As against the axial and volumetric straining, the acoustic activity experiences sharp changes at the boundaries between the deformation stages. This provides sufficient distinction of the boundaries, assessment of the related physical and mechanical properties of rock salt and identification of its deformation stages. The increase in the test temperature caused some displacement of the boundaries between the linearly elastic and elastoplastic stages of deformation as well as between the stages of elastoplasticity and failure. This displacement corresponds to the decrease in the elastic limit and ultimate longterm strength in each sample of rock salt with increasing temperature relative to the ultimate compression strength.

Keywords: rock salt, mechanical loading, deformation stages, acoustic emission, thermal effects, elastic limit, ultimate long-term strength, Karman’s scheme.
For citation:

Kravchenko O. S. Regular patterns of acoustic activity, axial and volumetric strains in rock salt under Karman’s loads and thermal effects. MIAB. Mining Inf. Anal. Bull. 2020;(4):96-104. [In Russ]. DOI: 10.25018/0236-1493-2020-4-0-96-104.

Acknowledgements:
Issue number: 4
Year: 2020
Page number: 96-104
ISBN: 0236-1493
UDK: 622.02:534.22
DOI: 10.25018/0236-1493-2020-4-0-96-104
Article receipt date: 17.01.2020
Date of review receipt: 21.02.2020
Date of the editorial board′s decision on the article′s publishing: 20.03.2020
About authors:

O.S. Kravchenko, Graduate Student, e-mail: ftkp@mail.ru, National University of Science and Technology «MISiS», 119049, Moscow, Russia.

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