Justification of the upper limit of slope formation when washing the tail storage tiers

Purpose. The method of determining the distance from the inner facelower edge of the embankment dam along the level of the wash to the point where particles of a given density and size will begin to fall from the flow to the dusting surface of the of washout, taking into account the flow rate and concentration of the water mixture, the slope of dusting surface of washout and the coefficient of friction of the soil from which it was formed in the article, for the conditions of collecting waste from mineral raw materials processing into artificial storages using hydraulic methods. Methodology. In contrast to existing methods, the approach used in the article provides for the upper limit determination of the particles concentration zone of a specific fraction, determined taking into account the critical flow regime, when the speed at which particles fall out of the flow is determined by the hydraulic particle size and the slope of the bottom surface flow. Results. The dependence of the relative upper limit of the slope during washing formation of the layer on the solid fraction parameters, the flow rate and the volumetric concentration of the water mixture coming from the pipeline was established. The dependence has a maximum, the parameters of which are determined by the density, diameter and friction coefficient of solid particles, as well as the value of the flow of the water mixture distributed along the length of the beachis shown. Scientific novelty. For the first time, the technique takes into account the influence on the material fractionation process of both particle density and their diameters. This makes it possible to calculate the occurrence of man-made deposits limits and predict the parameters and characteristics of man-made deposits formed in mineral raw material processing waste storages. Practical significance. For the first time it is possible to determine on the dusting surface of washout where the zones in which the particles of only one fraction are concentrated intersect, though it is possible to calculate the areas with a combined concentration of several fractions particles with the help of the formulas given in the article.