ABOUT FLEXURAL DEFORMATIONS OF THE ROOF ROCKS OF A COAL SEAM UNDER THE ACTION OF SHOCK LOADS
Journal Title: Вісник Кременчуцького національного університету імені Михайла Остроградського - Year 2018, Vol 1, Issue 110
Abstract
Purpose. To study the state of enclosing roof rocks under the action of dynamic loads on them, in the form of sud-den collapses of the flake off stratum, on discrete models of equivalent materials. The rocks of the roof of the coal seam which is being developed were considered in the form of a cantilever beam, of a certain length, which rests on a supple support which is a spring of constant rigidity. It is necessary to establish the impact on them of shock loads and the resulting flexural deformations. Methodology. A comprehensive research method using the basic concepts of theoretical mechanics, impact theory and modeling from equivalent materials have been used. Results. The use of a flexible support with a constant value of rigidity ensures stability of the side rocks in the vicinity of the supported mine workings with sudden collapse of the stratified strata or plantings of the main roof are researched. Originality. With the approach of the place of impact of the rock block with the beam to the flexible support, the deformations caused by the corresponding displacements reach their greatest value. This occurs not at the moment of the impact of the rock block with the beam, but after a certain time interval one after another, the magnitude of which depends on the physical and mechanical properties of the rock console, the mass of the rock block falling on the beam, the logarithmic decrement of the oscillations in the system and the damping properties of the compliant support. Practical value. Development of measures aimed at increasing the stability of mine workings in the development of coal seams in difficult mining and geological conditions. The use of a flexible support with a constant value of rigidity ensures stability of the side rocks in the vicinity of the supported mine workings with sudden collapse of the stratified strata or plantings of the main roof. But it is necessary to take into account the parameters of the rock console, the width of the face space and the mass of the collapsed rocks. Сonclusions. In order to prevent sudden collapses of lateral rocks in the development of steep coal seams, one should be guided by the use of a universal method for controlling rock pressure and protecting mine workings has been proved. References 37, figures 16.
Authors and Affiliations
S. Podkopaev, Е. Konopel'ko, I. Iordanov, D. Chepiga, А. Polozhij
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