N. A. Chinakal Institute of Mining Siberian Branch Russian Academy of Sciences, Novosibirsk, Russia:

A. F. Revuzhenko, Head of Laboratory, Professor, Doctor of Physical and Mathematical Sciences, revuzhenko@yandex.ru

The author gives a performance review of the Laboratory for Mechanics of Deformable Solid and Granular Media in connection with an anniversary celebrated at the Institute of Mining, SB RAS. A set of developed devices implements uniform shearing and various-path complex loading of granular and other materials alike. New regularities of elastoplastic deformation and dilatancy are described. Rocks and soil are known to contain different systems of joints, claypans and other structures. The Laboratory has developed an algorithm of experimental production of such structures. The algorithm is composed of three conditions. First, the process of loading should induce either uniform or nearly uniform distribution of strains in the medium. Second, the loading should be stiff, i.e., displacements should be set at the entire closed boundary. And third, the loading parameters should allow a loss in deformation stability. Implementation of the algorithm made it possible to discover some new structures. These results have contributed to the current concept of block hierarchical structure of rock mass. The concept of a rock as a medium capable to accumulate and release energy at different structural levels is developed. New invariants of stress tensor are obtained by averaging stresses in the plane of Mohr’s envelope. In the ranges of high stress gradients, it is required to construct and use nonlocal type models. In the framework of the mathematical models, the algorithms and software systems have been developed for the solution of various problems in mining.
The study was supported by the Fundamental Research Program, Projects Nos. AAAA-A17-117122090002-5 and AAAA-A17-117121140065-7.

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