About One Option of Calculation of the Trajectory of the Movement of Crack Loaded with Internal Pressure in the Roof of the In-seam Working



N.V. Cherdantsev, Dr. Sci. (Eng.), Laboratory Head, nvch2014@yandex.ru FITs UUKh SO RAN, Kemerovo, Russia

Annotation:

The results of the solution of the problem on creation of the trajectory of movement in the roof rocks of the in-seam working artificially created by the crack, which is under the influence of the liquid internal pressure, are presented. Vertical gravity of the loaded array is higher than the horizontal, and he is in conditions of plane deformation. The massif is loaded with equally component gravitational field of stresses, and is in the conditions of the flat deformed state. The issues related to emergence of the crack and liquid entering to it are not considered. The bedrocks and the layer roof are rather strong, and at reaching the limit state are destroyed as fragile materials.
The problem is solved within the model of geomechanical condition of the massif of rocks containing in-seam working, in which boards the limit stressed zones are formed. The model is created on the basis of basic provisions of mechanics of the deformed solid body. It is imlemented by means of the method of boundary elements and classical ideas on the condition of the crack, its stable and unstable growth in the infinite plane from fragile material based on Griffith — Irving theory.
Based on the results of the conducted researches the trajectory of the crack movement is created for a number of values of coordinates of its initial position and the angle of slope to the horizon. The schedules of change of critical pressures at the crack intergrowth are given.

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DOI: 10.24000/0409-2961-2017-12-5-10
Year: 2017
Issue num: December
Keywords : mine working massif of rocks the method of boundary elements coefficients of stress intensity crack Griffith — Irving theoriy
Authors:
  • Cherdantsev N.V.
    Dr. Sci. (Eng.), Chief Research Associate, nvch2014@yandex.ru, Federal Research Centre of Coal and Coal Chemistry of SO RAN, Kemerovo, Russian Federation