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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(a)

(b)

Fig. 4. An example of the rock deformation diagramsat different lateral pressures: a) sylvinite; b) carnallite

Table 1. Average values of the main mechanical indicators for the conditional instantaneous compression of the rock specimens of the GPD Lateral loading  3 , MPa Silvinite Carnallite σ str , MPa ε str , % σ str , MPa ε str , % 0 17.25 2.07 11.82 0.48 5.0 56.5 16.27 42.35 2.36 7.5 61.37 21.81 49.89 2.08

Based on the creep experimental results for various load levels, long-term deformation diagrams were constructed in the coordinates deformation ( ε 1 ) – time (t) , which were used to determine the steady-state creep rate and ultimate long-term strength (Baryakh et al., 1996; Bolikovand Konstantinova, 2003; Kartashov et al., 1979). The characteristic curves of creep under uniaxial and volumetric loading of sylvinite and carnallite are shown in Fig. 5-6.

Fig. 5. An example of typical sylvinite creep curvesobtained at different values of the lateral pressure