It was proved for the first time that rock mass is capable to create the dissipative structures (DS), which self-organize and facilitate their irreversible movement during accumulation of the damage to spend minimum potential energy for the same amount of the irreversible integral movement of the rock mass (Nazimko & Zakharova, 2017; Zakharova, 2018). These structures are triggered by random fluctuations of thermodynamic parameters such as pressure, temperature or volume. DS are a product of both the close interaction of adjacent blocks or ground fragments and the distant cooperation of the block clusters (Griniov et al., 2017). The ground fragments create short-lived clusters that move as an entirely aggregated body, which may eventually reintegrate into other clusters and blocks during progress of the irreversible ground moving.
DS facilitate the accumulation of degrees of freedom for a ground body to separate from the stable rock mass and develop a landslide or roof sag and even a fall in an underground opening. These patterns of nonreversible ground motion can be unveiled with incremental fields of ground movement. These increments should be as small as possible however not to be less than the error of measurement.
The patterns of ground irreversible movement and the dissipative structure vary in space and in time. The adjacent blocks and clusters promote their cooperation giving the way one after the other, moving in turn, alternatively. The anti-phase pattern of incremental block movement prevails and is the most important peculiarity of the irreversible behavior of the ground and a rock mass. A block delayed when the adjacent block accelerated and vice versa, what demonstrates the close interaction of the ground fragments.
An apparent distant cooperation manifested during the development of a damaged zone around an underground roadway when this zone sequentially expanded to all direction not at the same time but in turn. Possibility of synchronous active irreversible movement of surrounding ground in all directions (from the roof, sides, and floor) is negligible because it is not consistent with the second law of thermodynamics.
The close interaction and distant cooperation of the rock clusters create such patterns of DS as rotors, torrents, sources and sinks.
It is very important to investigate how patterns of DS and their evolution depends on the rate of loading. Preliminary researches indicate that on one hand, increase of the rate multiplies number of DS patterns. However on the other hand, high rate of loading shifts the path of loading and demands more energy (specific energy, reduced to the volume of the ground) to produce the same amount of irreversible ground movement.Basic investigation relied on experimental works due to actual measurements of irreversible ground movement in situ. Computer simulation will be another tool to investigate irreversible ground movement. This is the aim of future proposed investigation.
(Responsible: D.Sc. Prof. Victor Nazimko)