Review article

Long-term permafrost soils, which used to be widely spread in large areas of Mongolia, have been actively degrading and disappearing under the impact of modern global warming. Many buildings and structures built according to the first principle of construction on permafrost soils (namely, permafrost soils of the base are used in the frozen state preserved in the process of construction and during the entire period of operation of the structure), received deformation with loss of stability of the base, which affects the safety of structures and ensuring their normal operation. As an example of such cases, the authors consider the results of the comprehensive study of the soil at the base of the building in the town of Nalayh located in the suburbs of Ulan Bator city. As a result of research it is established that formation of vertical cracks and horizontal cavities is caused by degradation of long-term permafrost owing to the global warming.