云南某露天铅锌矿砂岩能耗规律及动态力学性能研究OA

Aiming at the design requirements of deep multi-bench blasting in an open-pit lead-zinc mine in Yunnan,impact tests were conducted on rock samples by using the Split Hopkinson Pressure Bar(SHPB)system to investigate the energy consumption law and dynamic mechanical properties of sandstone under different impact loads.The results show that when the impact air pressure increases from 0.25 MPa to 0.50 MPa,the incident energy,transmitted energy and absorbed energy of sandstone samples increase linearly,while the reflected energy rises in a quadratic polynomial trend.With the strain rate increasing from 53.09 s-1 to 126.57 s-1,the damage degree of sandstone specimens intensifies and fine fragments increase.The energy consumption per unit mass rises from 0.02 J/g to 0.29 J/g,showing a linear relationship between energy consumption and strain rate.This study reveals the quantitative relationship between the dynamic compressive strength of sandstone and strain rate.It is proposed that the charge weight should be increased in deep high-stress areas to match the dynamic strength of rocks and avoid under-blasting or over-blasting.The research findings provide theoretical support for the efficient and safe exploitation of deep mineral resources.