Abstract:
In the process of mining with open stoping subsequent filling method, in order to reduce the damage caused by blasting impact during blasting and ore falling in the second step back mining room to the pillar of cemented filling after mining in the first step. Through the LS−DYNA software analyze the damage of two charge structures of air interval charge and sand−gravel interval charge to the adjacent cemented filling body during the blasting process under different reserved pillar thicknesses. The research results showed that the damage range of the retained ore body adjacent to the side of the cemented filling body and the change of the damage in the cemented filling body with the thickness of the retained ore body during the blasting process of the two charging structures were basically the same. However, compared with the sand−gravel interval charge structure, the air interval charge structure had lower energy consumption in the crushing zone, more energy was concentrated in the fracture zone, the explosive energy distribution was more balanced, and the rock breaking efficiency was better. In addition, throught the on−site monitoring of blasting vibration data, combined with the Sadov's formula for blasting vibration attenuation, the vibration monitoring data were subjected to multiple linear regression.The attenuation coefficients of blasting vibration in the
X、
Y、and
Z directions of the filling body were 2.31, 1.76, and 2.08, respectively, and the regression curve had a strong linear correlation, which was in line with the actual situation of the mine, the relevant attenuation coefficient could be used as the theoretical basis for controlling the maximum single−shot charge in the blasting process.The research conclusion provides a theoretical basis for the selection of blasting parameters in underground mining, and has certain guiding significance for safe underground mining.