Tula State University, Tula, Russia

S. V. Antsiferov, Head of the Department, Associate Professor, Doctor of Technical Sciences, antsser@mail.ru

Tulaproekt LLC, Tula, Russia

M. A. Kudryavtsev, Lead Engineer

The study of the stress-strain state of the soil around the workings carried out near the surface of the slope indicates its significant change in comparison with the untouched massif. As a result, there may be a violation of the initial equilibrium state of the slope, leading to a loss of stability of both the slope and the workings. The proposed method is one of the ways to solve the urgent problem of assessing the stability of an array of soil and underground facilities built in areas with complex terrain. The method is based on mathematical modeling of the interaction of the slope's soil mass and the production of a circular cross-section as elements of a single deformable system. The solution of the planar problem of elasticity theory for a semi-infinite weighty linearly deformable medium containing a reinforced circular hole near the inclined boundary is adapted to the assessment of slope stability. Analytical solutions to the problems posed were obtained by methods of mathematical theory of elasticity using complex Kolosov-Muskhelishvili potentials, Cauchy type integrals, properties of the Sokhotsky-Plemel theorem and the theory of Laurent series. This makes it possible, based on the analysis of the calculated stress-strain state of the soil mass obtained using analytical solutions to the relevant geomechanics problems, to assess the stability of slopes accommodating horizontal mining operations carried out in a closed manner parallel to the Earth's surface. The individual results of the performed studies are presented in the form of isofields of soil stability coefficients around loose and reinforced workings, obtained using the Coulomb-Mohr and Hoek-Brown criteria and allowing us to establish conditional zones of inelastic deformations of the massif. The established results can serve as an explanation for the causes of landslide processes observed during the construction of road tunnels in soft plastic limestones and marine clastic deposits in mountainous areas of Greece.

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