Research On Boundary Control Blasting Technology Of Open-Pit Mine Based On Shaped Charge

With the increase of the scale of open-pit mining,more and more problems are related to the penetration of shaped charge blasting into rock and soil.The rational use of’ shaped charge controlled blasting ’ It will benefit many aspects of mining.At present,Many general techniques require very small hole s Pacing,the drilling rig perforation cost and the number of perforation is relatively high,affecting the overall cost of the mine and mining efficiency.In view of the problem that the existing blasting technology is difficult to accurately achieve the directional fracture of rock mass and the small distance between adjacent holes,the " controlled boundary blasting " technology of open-pit mine based on shaped charge is proposed to achieve the goal of long-distance directional fracture of adjacent holes,and the results of increasing the distance between adjacent holes and improving the utilization rate of explosion energy are obtained.However,the complexity of its field lithology brings many difficulties to the field test.A lot of research on mine boundary re Pair,and the following research results have been obtained :(1)The thickness of the liner and the height of the shaped cavity have been increasing,and the depth of rock penetration has also been increasing,which is verified by numerical simulation.The cone angle also affects the penetration depth.The effect of shaped charge jet penetrating rock mass is the best when the height of ’ shaped charge ’ is1.5cm,the thickness of liner is 0.2cm and the angle of cone angle is 53 °.The shaped tube made of PVC material is used to replace the metal tube cover,which is economical,applicable and easy to process,and the directional fracture rock effect still exists.Com Pared with the ordinary charge structure,the explosive energy is distributed in the direction of energy accumulation,and the crack pro Pagation has obvious directivity.(2)Taking the similar model with the diameter of600 mm of cement mortar pouring as the research object,the test system composed of TST3406 and CS-1D Use some resistors to get the change display.The results show that the peak strain in the direction of energy accumulation is larger,and the failure effect of the circular shaped energy accumulation groove on the specimen is the most obvious.The blocking effect is good,the directional failure effect of the shaped charge structure on the hole wall is better,and the depth of the ’ groove ’ in the direction of the inner energy accumulation of the hole wall is obviously increased.(3)Based on the actual project,this chapter carries out on-site industrial tests in Zongyang Conch Group to verify that the shaped charge structure can increase the s Pacing of adjacent pre-splitting holes in pre-splitting blasting,from 2.5m to 3.0m.The hole s Pacing increases,the adjacent pre-splitting hole cracks penetrate,The stability of the reserved rock mass is protected,and this saves money.Com Pared with the conventional pre-splitting blasting,the shaped charge structure can increase the s Pacing of adjacent pre-splitting holes and ensure the crack penetration effect.This is conducive to crack pro Pagation,more practical for boundary trimming.Figure 61,Table 13,Reference 55...