Design and optimization of fractured rock mass blasting network structure of non black open pit coal mine

The structure of rock mass will change under long-time drought,little rain,windy climate conditions.There will be lots of joints and cracks in rock mass,so when blasting,it may appear that high block rate,blasting pile irregular,flying wounding accidents and so on.Based on the blasting test,the design adopts the asymmetric "V" type oblique hole to hole millisecond blasting network.The large area of deep hole blasting can increase the free surface,and the circumferential tensile stress and radial tensile stress apparent effect.In this paper,through the theory and practice of non constructing fracture blasting of Montenegro open pit mine,the rock blasting block rate reduced 5%~7%,greatly improve the blasting effect.