STUDY OF THE INFLUENCE OF PARAMETERS TECHNOLOGICAL SCHEMES OF EXCAVATION ON THE SUSTAINABILITY OF MINE ROADWAYS WHEN IMPLEMENTING THE CONCEPT OF «SMALL MINES»

Abstract

Purpose. Investigation of the influence of the parameters of technological schemes of coal mining on the stress-strain state of the rocks containing the mine roadways in the implementation of the concept of «small mines». Methods. The study used the finite element method and the analysis method. Modeling was carried out by the method of dangerous sections. According to the first variant of the technological scheme, two dangerous sections were selected, according to the second – four. The solution of the problem was carried out in a volumetric setting with observance of the boundary conditions. Results. The analysis of the stress-strain state of the rocks around mine roadways, according to the compared options, made it possible to determine the expected state of the rocks and establish the parameters of the zones of possible destruction. From the point of view of rock stability at the stage of elastoplastic deformation of rocks, the compared options are almost equivalent. Taking into account the shorter time of maintenance of roadways, it is more expedient to use short longwalls. In this version, trapezoidal support is used as the main fastening in the roadways, and in the “traditional” version – metal arch support. It is shown that with significantly lower costs for maintaining mine roadways, their stability when using short-longwall technological schemes is better. The studies carried out make it possible to assert that for “small mines” with small production, technological schemes with short longwalls are more appropriate than the “traditional” technological schemes developed for complex mechanization. Scientific novelty. The study of the stress-strain state of rocks around mine roadways of various shapes and sizes during the analysis of technological schemes for coal mining with short longwalls made it possible to establish the orientation and parameters of the massif sections that pass into an out-of-bounds state. This was done for the first time for the conditions of the Ukrainian Donbass. Practical significance. The availability of information about the expected stress-strain state of the rock mass allows timely planning of methods of fastening and measures to increase the local stability of rocks. Keywords: stresses, deformations, development, coal mine, technological schemes of excavation.