Abstract: The subject of research is natural and man-made kurums (blocky accumulations of rocks). The purpose of the work was to analyze the main literary sources, in which the results of research on the formation of the thermal regime of rock dumps (kurums) were published. The retrospective period of the research extends for more than 50 years. Domestic and foreign sources of information are considered. The most representative ones have been selected for analysis, in which the results of research with theoretical value and practical significance have been published. The analysis showed that on many important aspects of the formation of the thermal regime of natural and man-made kurums, all the authors of studies conducted in different regions and at different time periods, independently of each other, came to the same conclusions. This indicates the reliability and objectivity of the results obtained. An analytical review of scientific articles was used as a research method, in which research materials on the formation of the thermal regime of both the kurums themselves and their soil bases were published. The kurums of the permafrost and island permafrost zones are considered. An analytical review of literary sources containing theoretical and practical results of research on the formation of the thermal regime of natural and man-made kurums is carried out. The results of the analysis allow us to draw the following main conclusions. 1. Any types of natural and man-made kurums lead to progressive cooling of the base on which they are located. 2. When interacting with the rock base, the technogenic kurum works as an active thermal protection, changing its thermal resistance during the annual cycle. 3. When modeling the process of thermal interaction of technogenic kurum, it is quite acceptable to consider the kurum as a heat-protective layer, the thermal resistance of which depends on the effective coefficient of thermal conductivity, which changes its value when the sign of atmospheric air temperature changes. Based on the analysis of the results of the published works, conclusions are drawn about the possibility of a number of simplifications in the construction of computational models for forecasting and controlling the thermal regime of frozen bases of technogenic kurums.

Abstract: The subject of research is the underground structures of the cryolithozone (permafrost zones). The design of such structures, in particular the choice of space-planning solutions, methods and means of fastening rocks, unlike structures located not in frozen rocks, has a number of features and is associated with the need to take into account the zone of thermal influence of chambers operated with different thermal conditions constantly or periodically. For example, when changing the type of thermal regime in the chambers in cases of natural or man-made accidents and catastrophes. The purpose of the research was to determine the zone of thermal influence of a single chamber of an underground cryolithozone structure, depending on the type of fastening used (in the presence and absence of a thermal protective layer) and the duration of the operational period, using various calculation formulas. To achieve this goal, three types of formulas were studied that determine the dependence of the dimensionless radius of thermal influence of chambers on Fourier and Bio criteria. Multivariate calculations were performed using the formulas, which are presented in the form of 3D graphs. The analysis of the performed calculations showed that the calculations for all three formulas give similar results in a fairly wide range of changes in the initial parameters. Moreover, the formula, which does not take into account the influence of the Bio number on the radius of thermal influence, gives a certain calculated margin. In general, it is shown that the higher the value of the Bio number, the less its effect on the depth of the thermal influence zone of the underground chamber. Small values of the Bio number (up to 5-6) are typical for cameras that are fixed with sprayed concrete or have special heat-protective coatings.It is established that when choosing space-planning solutions for underground structures to assess the influence of the thermal factor, it is quite acceptable to use an approximate formula to estimate the radius of the thermal influence of a single chamber. The scientific novelty lies in establishing the scope of the studied formulas for predicting the radius of the zone of thermal influence of cameras with various types of fastening and thermal protection.

Abstract: When designing cryolithozone engineering structures, proper consideration of the thermal factor largely determines their subsequent reliable and safe operation. One of the important indicators when choosing design solutions is the coefficient of thermal conductivity of materials used in the construction of objects. The accuracy of determining the thermal conductivity coefficient also depends on the accuracy of determining the thermal resistance of heat-protective structures. The coefficient of thermal conductivity of materials is usually selected from the reference tables. When using mixtures of materials, the coefficient of thermal conductivity is determined by calculation. The purpose of this work was to compare the calculated values of the thermal conductivity coefficient of binary mixtures (a mixture of binder and filler) determined by the formulas of K. Lichtenecker and P. Schwerdtfeger. The comparison was carried out in the range of changes in the properties of materials characteristic of heat-accumulating and heat-insulating mixtures. It is established that for heat-accumulating mixtures, both calculation formulas give similar results. For thermal insulation mixtures, the results differ significantly. Moreover, the discrepancy for some ranges of changes in filler concentrations is hundreds and thousands of percent, which indicates a complete disagreement of the results obtained. The validity of applying one or another formula in different ranges of changes in the initial parameters for thermal insulation binary mixtures needs separate special studies.
Note that the results obtained and the conclusions drawn can be extended to compare the formulas of K.Lichteneker and V.I.Odelevsky.
At the same time, at this stage of research, it is not possible to reliably determine which of the two formulas should be used when calculating the thermal conductivity coefficient of thermal insulation mixtures.

Abstract: One of the important parameters determining technical solutions in the design of highways in the cryolithozone is the depth of thawing of the soils of the road base. The aim of the work was to quantify the degree of influence of the iciness of the soil foundations of roads in the cryolithozone on the depth of their seasonal thawing. For the analysis, the classical formula for calculating the thawing depth for bodies of plane symmetry, obtained by solving the single-phase Stefan problem, was used. The results of calculations are presented in the form of 2D and 3D graphs, which allow us to visually assess the effect of the iciness of the soil and the degree of its change during the operation of the road on the depth of thawing of the road base. It was found, in particular, that the degree of change in the depth of thawing at the same value of the increase in ice content in different ranges (for example, from 10 to 20% and from 30 to 40%) for the considered typical case of the ground base of the cryolithozone decreases by almost 1.3 times. It is shown that the greater the initial iciness of the soil, the degree of decrease in the depth of thawing when the iciness changes by a constant value will be less. A 3D graph was built to determine the depth of thawing of the soils of the active layer of the road base in a wide range of possible changes in ice content during the construction and use of the highway. The availability of a schedule allows to quickly assess possible options for changing the depth of thawing and make a correct, informed technical decision when designing the road. For example, when assessing the need to use a special heat-protective layer in road clothing. Further directions of research in this area should be aimed at studying the effect of humidity (iciness) of dispersed soils on the depth of thawing of road foundations, taking into account the dependence of the density and thermal conductivity of the soil on the iciness.