Malich M., Katan V., Laikov D., Kravchenko K. Fracture diagrams of prismatic specimens with a refined contact stress distribution law

Geotech. meh. 2025, 173, 112-122

 

FRACTURE DIAGRAMS OF PRISMATIC SPECIMENS WITH A REFINED CONTACT STRESS DISTRIBUTION LAW

1Malich M.

2Katan V.

1Laikov D.

3Kravchenko K.

1Ukrainian State University of Science and Technology

2Oles Honchar Dnipro National University

3Dnipro University of Technology

UDC 622.83+539.4

Language: English

Abstract. The extraction and further processing of minerals are associated with the improvement of existing and development of new resource-saving technological solutions for underground and open-cycle operationsThe most costly technology for processing mineral raw materials is destruction itself, which accounts for about 20% of total electricity production and up to 50% of total capital and operating costs. To determine the stability of the rock mass in an ultimate state, a stress-strain diagram of rock is used. To analyse these diagrams, it is necessary to know the distribution of contact normal and tangential stresses. According to classical solutions to this problem, the stress distribution was determined using the methods of L. Prandtl and E.P. Unksov. However, these methods did not account for the occurrence of stresses perpendicular to the compression vector.

The article provides further development of the method for refining the distribution of contact stresses and constructing a “normal stress-longitudinal deformation” diagram and limit curves, taking into account contact friction under load. A comparative assessment of the proposed method with diagrams constructed using the classical method is carried out.. The proposed method allows determining the strength limit and residual strength of rock samples based on parameters that can be easily established experimentally in the laboratories of mining enterprises. The results can be used to monitor the condition of the rock mass and ensure effective rock destruction.

Therefore, an improved method for determining the distribution of contact normal and tangential stresses in prismatic samples of brittle, relatively homogeneous rocks under stress is proposed, which takes into account stresses perpendicular to the load vector and allows for a more accurate assessment of the stress-deformed state of the samples taking into account contact. It has been established that, especially at small angles of internal friction, the level of current stresses according to the proposed method is lower than that obtained using classical solutions.

The developed approach allows avoiding the influence of the scale effect and transferring the results of laboratory studies to real, undamaged and relatively homogeneous arrays. The results are of practical importance for assessing the stability of rock masses and improving the efficiency of rock destruction during the extraction and processing of solid minerals.

Keywords: contact, friction, diagram, rock, deformation, stress, destruction

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About the authors:

Malich Mykola, Candidate of Sciences in Engineering, Ukrainian State University of Science and Technology, Department of Industrial Engineering, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. (Corresponding author)

Katan Volodymyr, Candidate of Sciences in Physics and Mathematics, Oles Honchar Dnipro National University, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Laikov Dmytro, Postgraduate student,Ukrainian State University of Science and Technology, Department of Industrial Engineering, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Kravchenko Kostiantin, Candidate of Sciences in Engineering, Dnipro University of Technology, Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.