Opencast Step Presplit Research And Application Of Blasting Parameter Optimization

Mining is to provide raw materials and energy industries for the national economy, the majority of outdoor metal mines are used in the treatment of side slope blasting technology. Blasting technology can effectively override and control the rock burst, which is widely used in the open pit slope treatment. Therefore, it is necessary for the production of pre-splitting mine blasting parameters are optimized to accelerate the rate of mine production and construction, maintenance, slope stability, reduce blasting costs, thereby obtaining good economic and social benefits.In this paper, how to form the slope Dagushan process by helping in the case of a flat and stable surface pre-split for the study, the main parameters of the network through the hole blasting rock types and millisecond intervals, using ANSYS/LS-DYNA software and optimized according to production test, the optimal parameters of the main blasting rock blasting species. Pre-split blasting in the field test, the observed occurrence rate half hole, pre-crack surface smoothness and the extent of damage, and the use of blasting vibration test observations drop shock effect, through the pre-split blasting evaluation after comprehensive evaluation model to optimize the design of the pre-split blasting blasting effect.By theoretical analysis, laboratory testing and field trials, made the following findings:(1) Based on the test results show that the triangular cloth hole, it can be the equivalent resistance line and form a more uniform stress field, which destroyed most unfavorable region significantly reduced, explosive energy distribution more uniform, to ensure blast fragmentation effect.(2) By ANSYS/LS-DYNA finite element software, and the optimal blasting rock blasting parameters Dagushan major species. Magnetite, granite hole network parameters are adjusted to7m x6.5m, between the holes millisecond time25ms, ranked among millisecond time is65ms. Hole network parameters adjusted gneiss8m×7.5m, between the holes millisecond time25ms, ranked among millisecond time is65ms. After several main types of rock blasting parameters optimized for half of the porosity increased significantly reduced vibration, reduced roughness, the extent of damage is significantly reduced.(3) To achieve a fine idea of blasting the concrete practice in a large open pit mine, breaking the traditional segment to another to determine the limitations of existing detonators millisecond of time, so that the design rationalization millisecond time.(4) The use of fuzzy mathematics in the summary and analysis of the effect of pre-split blasting characteristics and influencing factors on the basis of a new method for evaluation of pre-splitting blasting effect, the establishment of a pre-split blasting open pit mine slope comprehensive evaluation model proved fuzzy mathematical evaluation of the effect of the pre-feasibility blasting crack.