Erosion of the frozen riversides of the northern rivers depending on the direction of the coastal slope

The problems of hydraulic engineering require expansion of the scale of research on destructive coastal processes of water bodies located on the territory of the permafrost. Subject: of research in this article are the slopes of the rivers located in the zone of frozen rocks, and the main possible processes on them, occurring under the influence of various seasonal factors. The aim of this work is to study the thermo erosion slope processes of permafrost with allowance for hydromechanical and thermodynamic factors and the development of the main characteristics of these processes, as well as the construction of a single model that allows estimating and predicting the effect of seasonal conditions (including spring snowmelt and exposure to solar radiation) on possible destructive coastal processes at water bodies located on the territory of the permafrost zone. Materials and methods: theoretical analysis and generalization of known achievements in the field of hydrology and glaciology, the theory of slope processes, sediment transport, mechanics of frozen soils, and filtration. As a factual material, the data of laboratory experiments carried out in the PFUR hydraulic laboratory on a facility that allows varying rain currents of varying intensity, while measuring both the rate and number of infiltration flows, and the amount of side flow in the case of frozen or partially thawed soil, that were used as factual material. A various soil structure was modeled by freezing or introducing ice interlayers. Such studies in the laboratory were conducted for the first time. Results and conclusions: a method for predicting thermo-erosion is proposed taking into account the effect of seasonal conditions on permafrost. The influence of the direction of the coastal incline on the rate of thawing of soils under the influence of solar radiation is studied. The influence of ultraviolet rays on snow melting is different from the influence of infrared rays, since short waves (UV) penetrate deep into opaque substances and are transformed into heat fluxes within the snow layer. Cloudiness is a deterrent only for the IR portion of the spectrum. It has been shown experimentally that the dependence of the erosion of solid matter on the slope angle (other things being equal) will have a exponent (4/3) form. Thawing and erosion of frozen water bodies are proportional to the square root of time. The linear coefficient depends on the nature of the rock, ice content, ambient temperature and flow temperature. On the basis of the results obtained, it is possible to give practical recommendations for preventing and reducing the negative impact of the destructive processes under investigation, which is especially important for those areas where intensive hydrotechnical construction is being carried out.