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Background. When developing anti-landslide measures during construction on unstable slopes, an assessment of the degree of their stability should be carried out first. When using analytical (conventional) [19] calculation methods, such an assessment is conducted by calculating the stability coefficient (Ks ), which is characterised by the ratio of forces and/or moments holding the soil massif on an inclined surface to the forces shearing this massif.Aim. Within the framework of Soviet and, further, Russian practice, anti-landslide measures are commonly developed based on determination of the magnitude of landslide pressures. However, with the introduction of foreign methodological approaches and respective software applications into the practice of slope stability calculations, the question arises whether these applications can be used for determining landslide pressures and what additional approaches exist for calculating and justifying engineering protection structures on landslide and landslide-prone slopes.Materials and methods. The main conclusion of the study is the inexpediency of using the method proposed by G.M. Shakhunyants and the inadmissibility of using limit equilibrium methods to calculate landslide pressures when designing engineering protection structures.Results. The best option for calculating such tasks is to use an extended method of marginal equilibrium. However, this approach is practically not used in Russian practice. Alternatively, we can recommend an analysis of the deficit of retaining forces based on the methods of marginal equilibrium (referred to as reverse analysis in foreign terminology).

Introduction. The application of geographic information system (GIS) technologies is a promising technology for mapping and evaluating landslide hazards. At present, satellite-based terrestrial sensing is widely used. Satellite images make it possible not only to identify individual landslides, particularly in hard-to-reach areas, but also to identify those locations where landslide processes have manifested, are manifesting and may manifest themselves in the future.Aim. Mapping of the present landslide propagation in the territory of the Norak region of Tajikistan using satellite imaging and GIS.Materials and methods. In the course of the study, maps of landslide propagation were compiled both automatically and manually. An analysis of the results of previous studies and interpretations of satellite images was conducted. Digital models of the relief, as well as topographic, geomorphological, engineering and geological maps, were investigated.Results. A detailed map of landslide phenomena was compiled in the GIS format and a database of landslide phenomena was created for the first time for the territory of the Norak region of the Republic of Tajikistan.Conclusions. The conducted zoning showed that, out of the total landslide number, 24%, 36%, 10%, 18% and 12% correspond to very small, small, medium, large, and very large landslides, respectively. The landslide processes are developed across the area of 2601×104 m2, which accounts for the 4% of the total area of the district. The results demonstrate that the approach used in this study may be applicable to the landslide hazard assessment in hard-to-reach and poorly studied regions.

The coastal territories of the Red River, passing through the city of Hanoi (the capital of Vietnam), are developed very dynamically by different types of construction, sand extraction from the river bed and its banks, pumping of water, creation of ponds and agriculture. But these activities are only possible in areas protected against annual floods with a dam. However, in recent years, the intensity of lateral erosion of the river and associated suffocation and landslide processes has become rapidly increasing in both flood and dry seasons. Deformations capture natural river banks and the dam body. The authors analysed the causes and identified mechanisms of these processes taking into account variable climatic, tectonic, hydrological, geological and hydrogeological conditions complicated by economic activities in the coastal zone. The article provides calculations of the stability of banks in different conditions (during and after the flood), which confirms theoretical ideas about the mechanism of the process and coincide with the observations. The greatest contribution to the banks destruction is the variability of the internal friction angle of the sands entering the section of the coastal territory.

The development of Stoylensky iron ore opencast mine during the 50 years is accompanied by the extraction of huge masses of rocks and ores, that radically changes the stress-strain state of the array and the formation of a technogenic aquifer. The long-term quarry exploitation has a result of progressive development of engineering-geological processes: scree, landslides, creeps, suffusion. The development of processes initiated by technological works has a progressive space-time character. The solution of problem of the open pit slope stability which provides accident-free conducting of mining operations at long-term development of the field, is based on modern methodology of calculations. The angles optimization algorithm of slopes staking on Stoylensky iron ore open cast mine and the calculation of the coefficient of stability by different methods with the consideration of the anisotropy of strength properties and fracture density of the solid rock, have been suggested.

The paper discusses the methodology for assessing stability of pit walls in hard rocks, taking into account geological and structural features the rock mass and spatial position of weakness zones in relation to the pit walls. It is shown that, depending on the walls mutual orientation, the problem of pit wall stability can be solved in two-dimensional or three-dimensional formulation. Examples are given for assessing pit wall stability taking into account weakness zones in two-dimensional formulation by limit equilibrium and finite element methods, and, in three-dimensional formulation, by the method of volume rock blocks. Modern strength criteria, which are recommended to be used for modeling pit wall stability to prevent rock landslides, are described. The proposed method for assessing pit wall stability in hard rocks allows reasonable selecting the calculation method depending on structural pattern of the rock mass and the pit walls spatial position.

The article gives the comparison of the slope stability calculation results using different types of soil properties distribution in the slope massive. Four models of soil properties distribution in the landslide hazardous slopes are considered: the way used in domestic engineering geological practice - soil properties parameter values are set within outlined geological items; the abroad practice way - soil properties normative values are set within selected lithological types; proposed to consider the new approaches - the values of soil properties are set discretely within the outlined geological items; values of the properties of soils are specified discretely in a massif. The analysis of the slope stability general assessment using different principles of soil properties distribution shows that they have influence on the sliding surface position and the coefficient of slope stability value. Therefore the slope stability problem correct solution must be performed with the substantiation of soil properties distribution model in the slope massive.