Method for controlling the floor heave in mine roadways of underground coal mines

Purpose. The method development and research on controlling the floor heave of mine roadways located in the zone of increased stresses by local strengthening the rocks with mixtures expanding in the solid phase. Methods. The work uses the following research methods: analysis and generalization of previously performed research on the process of heaving the floor in mine roadways; full-scale mining studies, which include instrumental measurements at benchmark stations, rapid measurements, photo-fixation of floor rock cuts in the areas of dinting. Findings. It has been determined that the problem of heaving the floor is relevant for most of the temporary roadways located in the zones of increased stresses, for example, in the zone of longwall face impact, both Ukrainian and foreign coal mines. The conducted full-scale mining studies have revealed that the floor rocks in the zone of increased stresses are in a destroyed state and can be represented as a block-discrete medium. A method for controlling the floor heave in mine roadways has been developed, which is based on the formation of locally strengthened zones of a special shape in the mine roadway floor. The strengthening effect is achieved by consolidating the rocks due to their compression by mixtures expanding in the boreholes drilled into the floor of the mine roadway. The method parameters have been calculated which make it possible to set the necessary expansion pressures for the formation in the mine roadway floor of a stable strengthened zone of a specified shape. Studies on the formation of local strengthening of floor rocks with mixtures expanding in mine conditions substantiate the fundamental possibility of rock consolidation. Originality. The ideas about the consolidation of a block-discrete medium by compression and the formation of stable strengthened zones with mixtures expanding in the solid phase have been developed. Practical implications. A method for controlling the heaving of floor rocks and a methodology for determining the method parameters have been developed. The results obtained can be used to ensure the stability of mine roadways in zones of increased stresses.