Author 1:
Name & Surname: Pleshko M. S.
Company: Rostov State University of Transport Communication (Shakhty, Russia)
Work Position: Professor
Scientific Degree: Doctor of Engineering Sciences
Contacts: mixail-stepan@mail.ru

Author 2:
Name & Surname: Pashkova O. V.
Company: Rostov State University of Transport Communication (Shakhty, Russia)
Work Position: Postgraduate

Author 3:
Name & Surname: Nasonov A. A.
Company: Shakhty Institute, Platov South-Russian State Polytechnic University (Shakhty, Russia)
Work Position: Assistant Professor
Scientific Degree: Candidate of Engineering Sciences

In view of the evident tendency toward deeper level mineral mining, complicating ground conditions and intensified geomechanical processes and dynamic events of rock pressure, the authors report the results of in situ research (monitoring) and ultrasound diagnosis of solid concrete lining in mine shafts in order to detect damages, cavities, cracks, foreign inclusions, decrease in thickness and other changes of geometrical parameters of the lining, first of all, down the reduction of the design safety factor. The dominant causes of geometrical heterogeneities in concrete lining of mine shafts in course of construction and operation are identified. In three test areas of a mine shaft, reduction in the lining thickness made 15–20% of the design value. Based on the ultrasound scanning data, the authors implemented mathematical modeling of the lining areas with the changed geometrical parameters and the comparative modeling of the area with the design parameters. The analysis of stress–strain dynamics in concrete lining and safety factor used the Mohr–Coulomb criterion. On the mathematical modeling basis, the authors derive the expression for estimating stress concentration factor in concrete lining area with the changed thickness applicable to assessment of lining safety factor and mine shaft stability.

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