PSI - Issue 32

Artem Udartsev et al. / Procedia Structural Integrity 32 (2021) 187–193 Author name / StructuralIntegrity Procedia 00 (2019) 000 – 000

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mode and being in a volumetric stress state (Pankov et al., 2013;Agnieszka, 2017). Thus, it is relevant to study how sylvinite and carnallite are deformed under conditions of volumetric and uniaxial creep. 2. Experimental Studies To reach the assigned objectives, 45 sylvinite and 48 carnallite specimens were made from the core of the geological exploration wells drilled at the Gremyachinskoye deposit. The pictures of the prepared specimens of sylvinite and carnallite rocks are shown in Fig.1. To find the acting loads during creep, some of the prepared specimens were tested under conditional instantaneous uniaxial and volumetric compression, on average, 5-6 specimens from each batch. Determination of the conditional instantaneous strength and deformation characteristics of the salt rocks was carried out in a controlled loading mode at a constant deformation rate, in accordance with the requirements and recommendations set forth in (Bieniawski and Bernede, 1979; Kovari et al., 1983). Based on the experimental results for uniaxial and volumetric compression, complete deformation curves were constructed in the coordinates stress ( σ 1 ) – deformation ( ε 1 ) , which were used to determine the ultimate strength ( σ str ) and failure strain ( ε str ) at the ultimate strength (Baryakh et al., 2008).

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Fig. 1. Produced specimens of rocks:a) sylvinite; b) carnallite

Fig. 2. Servo-hydraulic press МТ S-815 for conditional instantaneous compression tests