Research On Blasting Parameters And Charge Structure Of Dahongshan Copper Mine

Drilling and blasting method is still the main rock breaking method in China’s metal mines.Therefore,it is necessary to conduct in-depth research on the blasting parameters of underground mining sites in order to improve the economic benefits of mining enterprises and provide technical support for efficient and safe mining.This paper relies on the research on the key technology of blasting parameters design in the adjacent panel of Dahongshan Copper Mine,determination of basic hole network parameters of underground mining blasting by series blasting funnel test,simulation of radial and axial stress distribution of air-spaced charge structures by finite element software LS-DYNA,comparison of the vibration reduction rate of air-spaced charge and segmented charge,the air-spaced charge structure is used to replace the original sand-segment segmented charge structure of the mine.The millisecond delay interference vibration reduction principle and HHT method are used to study the delay time of the blasthole row.The blasting funnel test was carried out based on the Livingston blasting funnel theory.Single hole blasting crater test,variable hole distance blasting crater test and inclined step test were carried out at 485 level 48-49 line and 26-28 line of 405 level in this part,it is preliminarily determined that the hole network parameters of the 48-49 line aperture 76 mm blasthole are(1.8~2.2)×1.0m,the unit consumption is 0.56kg/t,and the hole mesh parameter with aperture 165 mm is(4.5~5.4)×2.4m.The unit consumption is 0.45kg/t;The hole mesh parameter of the 26-28 line aperture 76 mm blasthole is 1.8×1.0m,the unit consumption is 0.57kg/t,the hole mesh parameter with aperture 165 mm is 4.5×2.4m,and the unit consumption is 0.47kg/t.Numerical simulation of establishing air-spaced charge and sand spacer charge,the radius of the comminution zone of the two charge structures,the equivalent peak stress around the blasthole,and the time of the detonation wave stress are compared,from the perspective of energy fragmentation,the radius of the crushing zone of the air-spaced charge is small,the equivalent peak stress around the borehole is small,the energy consumed in the crushing zone is less,more energy acts on the fracture zone,and the stress action time Longer,the explosive energy utilization is uniform,and the rock breaking effect is better.Therefore,it is recommended that the charging structure of the underground mining site of Dahongshan Copper Mine adopts an air-spaced charging structure.Based on the delay time interference vibration reduction and HHT method,the results show that the blasting vibration period of the underground mining site in Dahongshan Copper Mine is about 24~28 ms.It is recommended that the large blasting row delay time of the Dahongshan copper mine underground mine should be 36~ 42 ms can reduce the damage of blasting vibration to underground buildings,people and equipment.