Relevance. Engineering-geological surveys are an integral part of mining operations for various purposes. The quality of soil core sampling has an important impact on the results of engineering geological surveys. At the same time, obtaining a frozen rock core is complicated by an increase in the bottomhole zone temperature, which arises as a result of drilling. As the temperature rises, the physical and mechanical properties of frozen soils change, which leads to a transformation of the mechanism of their destruction and an increase in the likelihood of drilling emergencies. A core obtained under conditions of rising temperature does not allow for a reliably accurate assessment of the properties and structure of soils in their natural conditions. Therefore, there is a need to develop technological and technical means that help maintain the temperature regime of a rock mass under mechanical effect on it. The analysis of the conditions of core drilling in frozen rocks showed that, along with technological reasons, the design of the rock-cutting tool affects the increase in bottom-hole temperature. The article reveals the dependence of the temperature change at well bottom when drilling on the design features of the core rock-cutting tool. Aim. To study the impact of the design features of a drilling core tool on the nature of destruction of frozen soils, represented by loose sedimentary rocks as the most susceptible to changes in physical and mechanical properties with increasing temperature. The study was based on frozen soils that make up the section of Yakutia, a large industrial region that requires frequent geotechnical surveys for its development. Objects. Core drilling tool design, mechanism of frozen rocks destruction, conditions for core sampling in frozen soils. Methods. Analytical method, experimental method, production test method. Results. The authors have determined the main directions for the development of core tools for high-quality core sampling in frozen soils. They derived the dependence of the magnitude of the temperature increase at well bottom on the orientation and size of the cutters reinforcing the rock-cutting tool.
来源平台：BULLETIN OF THE TOMSK POLYTECHNIC UNIVERSITY-GEO ASSETS ENGINEERING
