The objective of this work is to substantiate the hereditary character of the stresses and deformations accumulation in loose mined rock during the disintegrators working surfaces convergence. It is shown, in particular, that the layer porosity after compression and the side thrust coefficient depend not only on the applied pressure, but also on the initial porosity. It is substantiated the mechanism of interrelation between the stresses and deformations of a layer. The experimental researches on fine– grained granite compression in a rigid matrix have been fulfilled. The approximation of obtained results by polynomial functions has been carried out. The coefficients have been determined by the least-square method. The close agreement of the analytical and the experimental values has been recorded. The initial porosity parameter was put into the equation of dependences of the current porosity and the side thrust coefficient on pressure. The mechanism of the forces distribution on separate particles contacts has been explained in terms of the material compacting hystory. The practical value of the research is in calculating the disintegrators operating parts parameters with account of the mined rock layer condition prior to the act of crushing.

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Purpose is to substantiate the parameters and factors in terms of which amber can be mined efficiently from sand deposits using hydromechanical method. Methods. Laboratory studies and full-scale experiments of amber-bearing sand with 2-50 mm fractions were carried out to substantiate velocity of amber buoying up to the sludge surface. Amber from Klessiv and Volodymyrets deposits were involved. Computer research relied upon Curve Fitting of the software environment Matlab. Analysis of amber particles, buoying up to the surface, relied upon a theory of particle motion within the sand formation, characterizing by motion with resistance of a dry friction type. Methods of mathematical statistics were applied; then dependences were plotted describing the effect of mining parameters on the amber buoying up velocity. Findings. The basic parameters of hydromechanical method and parameters, effecting buoying up velocity, and dependence of dimensions as well as weight of the amber fractions have been identified. Dependences of the dominant factor effect on the process of amber buoying up to the surface of sludge-like rock mass have been determined to improve the efficiency of amber mining.Originality. Maximum period of the analyzed amber fractions, differing in their diameters, is not longer than 4 minutes.The results of the experimental data as well as computer-based experimental data have helped define that 3 rd order polynom with corresponding rational coefficients for various amber fractions, occurring in the sand amber-bearing deposits, is the most adequate to describe the research. It has also been defined that velocity of amber buoying up from amber-bearing sand medium depends upon effect on the process of the dominant factors; and geometry of amber fractions and their weight making it possible to apply a hydromechanical mining method. Practical implications. The obtained regularities of hydromechanical mining of sand amber deposits help calculate and select facilities for hydromechanical mining of amber.

New devices were developed to increase the extraction of amber, especially with the size less than 5 mm, which can not be extracted at the present time. They are made on the basis of a hydraulic spiral classifier using vibration and bubbling with air bubbles. Analytical formulas are needed to calculate such devices, in first, for free motion of particles, then the constrained motion, and then to determine the effect of vibration and bubbling on the speed. This article discussed the first part of the problem – hydrodynamics of free movement of amber and quartz particles in a mixture of amber sand-clay rocks with water. The technique and formulas of calculation of kinematic viscosity and speed of movement are given. The dependences of the kinematic viscosity and the speed of free deposition of quartz and free ascent of amber on the density of the suspension for particles size less than 5 mm are obtained. The non-linear character of the dependence of the speed of ascent of amber from the density of the suspension is set. The results obtained are the basis for the calculation constructional parameters and technological characteristics of the hydraulic classifiers of new construction.