Аннотация:One of the critical geoecological concerns of the present day in the developed countries of the world and in Russia is removal of immense amount of high-level radioactive wastefrom the biosphere. The only feasible way out is deep burial. Rocks should possess propertieswhich most certainly prevent the spread of radionuclides with groundwater over the whole period of biohazard (more than 10 thousand years). The insulating properties of rocks depend ontheir stress–strain behavior and thermal exposure. The HLW temperature may reach 1500 °Cand keeps on for 150–300 years. This article presents the analytical results on the time-seriesof unique observations over deformation of sidewall rock mass in underground facilities accommodating powerful heat sources at the Mining and Chemical Plant in Zheleznogorsk. Theanalysis aimed to explain the adjacent rock mass deformation mechanism and its correlationwith the temperature and rock mass quality (structural damage). It is found that the increase inthe temperature correlates with the increase in the amplitude of displacements in adjacent rockmass and that the process of sidewall rock deformation has a cyclic behavior. Over the periodfrom 1980 to 1998, the average displacement velocities were: 03–0.45 mm/yr in poor qualityrocks heated up to 50–700 °C (maximum velocity 4.65 mm/yr); 0.1–0.2 mm/yr in weakly damaged and heated rocks (maximum velocity 0.6 mm/yr); 0.02–0.04 mm/yr in undamaged rockmass with the natural temperature background. The proposed model of deformation processin time can be used as a framework for the geomechanical experimentation planning in anunderground research laboratory toward assessment of structural damage growth in rocks masscontaining a manmade heat source.
