Abstract
Aim: Determination of the principal technical characteristic of the explosion-stable mine stopping with embrasure pipes, i.e. thickness, depending on mechanical characteristics of the material, cross-sectional area and disposition depth of a mine working and external loads.
Methodology: The theoretical method of investigation of the stress state of the explosion-stable mine stopping being erected by the mine rescuers from gypsum with the use of one of the basic numerical methods of the solution of the boundary problems of the elasticity theory, i.e. the variation method, is applied.
Results: The mathematical model of the deflected mode of the explosion-stable mine stopping with embrasure pipes represented in the form of a thick plate with a radius of curvature changing according to the parabolic dependence under the influence of the normal and pressure load, and its three edges are fixed and the fourth one is free, is worked out; the distributions of the tensions in the stopping according to the relative coordinates depending on its thickness, mechanical characteristics of gypsum, acting loads, cross-section area and disposition depth of the mine working are received; the strength of the stopping with one embrasure pipe of 0.8 m radius is ensured in the mine working with the cross-section area from 4…30 m2 and with such two tubes - in the mine working with the cross-section area of 8 m2; the values of the stopping thicknesses received by the use of the mathematical model worked out are by 14 per cent lower on average than the values adduced in normative documents.
Conclusions: The mathematical model of the deflected mode of the explosion-stable mine stopping worked out allowed the scientific substantiation of its principal technical characteristic, i.e. thickness, depending on mechanical characteristics of the material, loading conditions, cross-section area and disposition depth of the mine working, what will guarantee the safe operation of the mine rescuers and cost reduction by erection of the stoppings as a result of accident elimination by the explosions in the coal mines.
Keywords: mine working, explosion, stopping, thickness, embrasure pipes, gypsum, mechanical characteristics, variation method, tensions, mathematical model
Type of article: original scientific article