Bezruchko K.А., Pymonenko L.I., Burchak O.V., Baranovskyi V.I., Prykhodchenko O.V. Residual deformations of coal during destruction under pressure
- Details
- Parent Category: Geo-Technical Mechanics, 2025
- Category: Geo-Technical Mechanics, 2025, Issue 172
Geotech. meh. 2025, 172, 93-104
RESIDUAL DEFORMATIONS OF COAL DURING DESTRUCTION UNDER PRESSURE
M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine
UDC 622.831.1:539.37
Language: English
Abstract. Deformation and destruction of rocks and coal during underground workings are the primary processes that define the stability of these workings, the nature and intensity of potential gas-dynamic phenomena. Rocks, from the viewpoint of mechanics, are complex and contradictory objects: they are highly heterogeneous in small volumes, whereas they tend to be relatively homogeneous in larger volumes. They act as solid bodies in small volumes but as discrete bodies in larger ones. Importantly, the concept of destruction includes elastic, plastic, and brittle stages of deformation. The authors examine the properties of residual deformations in coal that occur during its destruction under external pressure. The physical and mechanical properties of coal were analyzed during loading to destruction and after the removal of the load. The established relationship between the level of residual deformations and the structural characteristics of coal enables an assessment of its deformation resistance.
The work aimed to develop theoretical and experimental approaches to studying the mechanical properties of coal at the microlevel and estimating the magnitude of the energy of elastic deformations.
For the first time, it is shown for coal at the microlevel that under force loading, the direction of brittle (crack) and plastic (surface corrugation) deformations most often coincide, which reflects a gradual transition from plastic to brittle deformations.
It is shown that in samples of crushed coal during compression, deformations are distributed unevenly due to critical fluctuations in local differently activated zones: the energy of elastic deformations is concentrated in harder particles, and the distribution of both the particles themselves and the deformations in them has a local (random) character.
The elastic strain energy accumulated in crushed coal (size class 0.10–0.16 mm) during compression was calculated for coal grade LF, ranging from 0.20 J/g to 0.50 J/g with a change in compressive force of 0.03 kN to 0.05 kN. The results obtained can be used to improve models of mining pressure and predict the stability of mining operations in coal deposits. Additionally, research in this area is extremely important both for industry (efficiency and safety of mining operations) and for fundamental science related to the strength and deformation of materials to better understand the behavior of complex deformation systems.
Keywords: coal, compression, residual deformation, fracture, physical and mechanical properties, structural changes.
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About the authors:
Bezruchko Kostiantyn, Doctor of Geology Science, Senior Researcher, M.S. Poliakov Institute of Geotechnical Mechanicsof National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Head of Department of Geology of Coal Beds at Great Depths, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. (Corresponding author)
Burchak Oleksandr,Doctor of Technical Science, Senior Researcher, M.S. Poliakov Institute of Geotechnical Mechanicsof National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Head of Department of Geology of Coal Beds at Great Depths, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.
Pymonenko Liudmyla, Doctor of Geology Science, Senior Researcher, Principal Researcher in the Department of Geology of Coal Beds at Great Depths, M.S. Polyakov Institute of Geotechnical Mechanics under the National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.
Baranovskyi Volodymyr, Engineer, Junior Researcher of Geology of Coal Beds at Great Depths, M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.
Prykhodchenko Oleksiy, PhD of Geology Science, M.S. Poliakov Institute of Geotechnical Mechanicsof the National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Research Fellow of Department of Geology of Coal Beds at Great Depths, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.