Introduction. The conditions for determining the stable equilibrium of a landslide for any sliding surfaces, density, mass, volume and slope steepness are considered. The equilibrium equations for a landslide are given in rectangular coordinates. For this purpose, reference and deformation networks are created on the landslide slope. Depending on the size of the landslide body, the support network is designed in the form of a polygonometric course, the geometric parameters of which satisfy the accuracy characteristics of the course and the conditions of the work area. And based on the accuracy of the equilibrium equations, the required number of points of the deformation network is determined. The subject of the study is a mathematical model of a landslide created on the basis of geodetic observations and engineering-geological studies. The purpose of the study is to determine the possible condition of the landslide at the time of the observation. At the present stage, determining the conditions for the stability of a landslide is an important scientific and practical task, the relevance of which is beyond doubt.
Materials and methods. It is proposed to use an integrated approach, which is based on the joint application of the method of geodetic monitoring of deformation processes with engineering and geological studies. For geodetic monitoring, landslide and deformation geodetic networks are created, which are fixed on the terrain by geodetic signs, respectively, outside the zone of influence of landslide processes and directly on the landslide slope. At the same time, engineering and geological studies are carried out to obtain objective information on the physical and mechanical properties of soils. The article presents the equilibrium equations of the landslide body in rectangular coordinates determined in the process of geodetic monitoring, through the equation of the surface in general form and through the vector of the adhesion force.
Results. On the basis of the results of geodetic monitoring and engineering-geological studies, formulas were obtained for determining the stable equilibrium of a landslide for any sliding surfaces, density, mass, volume and slope steepness for their practical use and further prediction of possible landslide dislocations.
Conclusions. The formulas obtained make it possible to determine the stable equilibrium of a landslide based on geodetic and geological data. How exactly do these formulas allow us to determine the stable equilibrium of a landslide? This question remains open and requires further investigation by methods of error theory. The question is very important, since the definition of the landslide hazard assessment depends on it. If the landslide slope is built up, then the determination of the asses-sment of landslide vulnerability. Then it is possible to obtain a reasonable assessment of the risk and level of landslide safety of the frozen landslide slopes. These assessments are very important and can be further used in organizing the development of urban planning solutions, as well as in assessing the life cycle of intelligent sustainable cities.