Intensification of technological processes in drilling and blasting operations during open-cut mining in Kyzylkum region

Purpose. It is found that for long term standing, the pit bench profile is close to the boundary of the disturbed zone. Therefore, long stability of the bench can be estimated in respect to the size of the disturbed area and the boundary of residual deformations zone. Methods. Protective ability of the shielding splitting during the perimeter blasting in Kyzylkum quarries is estimated by the amplitude coefficient depending on the width of the shielding splitting, duration of explosive pulse as well as physical and mechanical properties of the shielding splitting filler. Findings. Analysis of the research regarding special methods of conducting drilling and blasting operations (DBO) for bench slope development showed that the most effective way of reducing deformation zone beyond the designed surface of separation is to use pre-splitting. Analysis of the research related to selecting parameters of contouring charges for creating a shielding splitting revealed the absence of methods which can reasonably and unequivocally recommend DBO parameters for specific mining and geological conditions. Currently known dependences only approximately allow to estimate the relationships between the main parameters of contouring explosives. Originality. In accordance with the “Research method of blast impact of contouring charges in the border zone of the quarry”, experiential and industrial tests of the developed blast design and effective parameters of perimeter blasting have been conducted in Muruntau quarry. As a result, stable slopes of 20-meter benches with the slope angle 60 degrees were formed, eliminating the need for additional wall cutback, simultaneously improving labour safety at lower horizons. The developed effective parameters of perimeter blasting ensured creation of maximal widest shielding splitting for the designed limit of the disturbance zone thickness with destroyed inter-block connections in the area adjacent to the slope. Practical implications. Fixing mixture underwent industrial testing and was implemented in Tashkura quarry of Djeroy-Sardara phosphorite fields. It was established that during explosive fragmentation of rock mass, using stemming of fixing mixture, the amount of dust and gas clouds is reduced by 30 – 35% as compared with stems made of drill cuttings.