Sakhno S. Improvement of the safety level of miners' work while supporting the underground roadways of aslope coal seams with rock bolts

The revealed regularities of strengthening of rocks by anchor bolts, which are fixed along the entire length of the borehole by self-expanding mixtures, for controlling the resistance of rocks, reducing rock falls and, consequently, reducing the level of injury miners from rock falls in roadways. It is established that "rock falls" is among the five most dangerous factors in the vast majority of coal mining countries, accounting for about 18% of fatal injuries in the coal industry in Ukraine. The number of rock falls and severity of injuries in the first place depend on the support type and its reliability. In the conditions of large deformations of the contour of roadways, destruction and rock falls, the immediate perspective of supporting is associated with the development of anchor systems that combine the frictional effect with adhesion and mechanical fastening. The influence of the basic mechanical parameters of the fixer, which provides the maximum energy intensity of the «rock bolt-fixing-rock» system with its non-destructive deformations, on the stress-strain state of the system is established. The range of their varios is determined in which the containment of the rock falls is ensured, which helps to reduce the level of traumatism in mining operations. The method of non-adhesive fastening of anchor bolts by self-expanding mixture in the process of hydration curing is proposed. Mine researches of the developed method of anchoring is carried out. The economic effect of the method 41.80 UAH / rock bolt. The method of estimating the risk of injury from the destruction of the roof in the roadways has been developed. A system for assessing the hazards of rock falls and the level of the risk of injury is proposed. An analysis of the developed method for assessing the risk of injury from the rock falls from roof, allowed to establish that, it is possible to reduce the level of probability of rock falls up to 8.9%. Key words: safety of miners, bolting, rock falls, injuries from rock falls, selfexpanding mixture, risk of injury to miners.