PSI - Issue 32

A.A. Baryakh et al. / Procedia Structural Integrity 32 (2021) 109–116 A.A. Baryakhet al./ Structural Integrity Procedia 00 (2019) 000 – 000

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depth of mining and the presence of hard rock strata in the geological section reduces the size of protective pillars under critical objects, thereby increasing the extraction of minerals.

Fig. 3. Predicted subsidence of the earth’s surface along the calculated profile:1 is 5 years after the first excavation; 2 is after 10 years; 3 is after 15 years; 4 is after 20 years; 5 is after 25 years; 6 is at the end of the displacement.

Fig. 4.The nature of the rock mass lamination along the border of the salt and dolomite strata:4 is 20 years after the first excavation; 5 is after 25 years; 6 is at the end of the displacement. 4. Geomechanical analysis of the stability of waterblocking strata As previously noted, the localisation of the plasticity zones in the underworked rock mass is closely related to its destruction in the rock jointing areas. When compressive stress is applied, plastic deformation is carried out through the formation of shear cracks, and in the tension region, it occurs due to the formation of the opening mode fractures. Within the settings described above, the destruction of the salt rocks due to shear is determined by the Mohr-Coulomb criterion, which can be represented as (9): ൌ ≥ ͳ (9) where , are found using expression (3). In the field of tensile stresses, the criterion for the destruction of salt rocks is defined in relation (10).