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The aim of the work is to study the stability of the roof rocks of the coal seam with a malleable support under the action of dynamic loads. To achieve this goal, laboratory studies were performed on models of equivalent materials, when the roof of the coal seam was presented in the form of a beam, which rested on a flexible support of various rigidity, depending on the modeling options. During the studies, the behavior of the simulated deformable system after the force of a falling rock on a beam was studied and it was found that taking into account the heterogeneity of the beam material, if there is a flexible support from loose rock that has different particle size, voidness and bulk density, the beam will be deformed over time lag behind its movement by the amount of phase shift, and, the lower the stiffness of the pliable support, the greater the time lag. The maximum displacement of the beam in the simulated system depends on the static compression of the compliant support and the possible deviation of the center of mass from the equilibrium position upon impact. With this interaction of the beam with a malleable support, the amount of energy spent on the beam deformation depends on the stiffness of the flexible support, the duration of the impact and the time interval between the end of the external force and the maximum movement of the beam, which has compliant support links. It has been proven that the stability of the simulated deformable system is ensured under conditions when the compliant support from the loosened rock, on which the roof rocks are behind the clearing face, has a hollowness of not more than M≤20% and not less than M≥7%, with an increase in its bulk density. With an increase or decrease in the hollowness of the pliable support, under the action of dynamic loads, destruction of the simulated beam occurs. A complex of laboratory studies on models of equivalent materials shows that the presence of a malleable support from loosened   ISSN 2079-5459 (print) ISSN 2413-4295 (online) СЕРІЯ "НОВІ РІШЕННЯ В СУЧАСНИХ ТЕХНОЛОГІЯХ" ВІСНИК НТУ "ХПІ" No 10 (1335) 11 © И. В. ИОРДАНОВ, Ю. И. СИМОНОВА, А. В. ПОЛОЖИЙ, С. В. ПОДКОПАЕВ, В. Ю. ДОВГАЛЬ, А. В. КОРОЛЬ, 2019 rock of reasonable particle size to maintain the roof of the coal seam behind the stope under the action of dynamic loads, ensures the stability of lateral rocks in the vicinity of the supported mine workings.

vìsnik nacìonalʹnogo tehnìčnogo unìversitetu "hpì". novì rìšennâ v sučasnih tehnologìâh/vestnik nacionalʹnogo tehničeskogo universiteta "hpi". novye rešeniâ v sovremennyh tehnologiâh

A study of the stability of the roof of the cobled plate with the suppressional support of various hardness on models