摘要
为研究攀枝花铁矿开采境界内铁矿石的动力学性能,利用动静组合分离式霍普金森杆实验系统,开展4种典型铁矿石的动态单轴压缩试验。以动态强度、能量耗散、碎屑分布为切入点,分析4种矿石的动力学响应特征。试验结果表明:4种铁矿石的动态强度均具有明显的率效应,随冲击速率的增加而增大;所研究冲击速率范围内,中低品位铁矿石的动态强度显著大于高品位铁矿石和表外矿的强度;随着冲击速率的增加,单位体积耗散能随之增大,且单位体积耗散能的增加幅度与铁矿石的品位相关;基于分形理论分析4种铁矿石破坏后碎屑块度的分形维数,发现碎屑块度的分形维数随冲击速率增大而增加;最后,分析了单位体积耗散能与分形维数的关系,发现二者呈现非线性正相关关系。
To study the dynamic performance of iron ore in the mining realm of Panzhihua Iron Mine,the dynamic uniaxial compression test of four typical iron ore was carried out by using the static-dynamic coupled Split Hopkinson Pressure Bar(SHPB)experimental system.The dynamic properties of the four ores are analyzed,including dynamic strength,energy dissipation,debris distribution.The test results show that the dynamic strength of all types of iron ores have obvious rate effects,which rise with the increase of the impact rate;within the range of the studied impact rate,the dynamic strength of the medium and low-grade iron ore is significantly greater than that of the high-grade iron ore and off-surface ore;with the increase of impact velocity,the dissipation energy per volume increases,but the increase value of the dissipation energy per volume is related to the grade of iron ore;the fractal dimension of the fragmentation are analyzed based on fractal theory,it is found that the fractal dimension of the fragmentation increases as the impact velocity increases;finally,the relationship between the dissipation energy per volume and the fractal dimension is analyzed,and it is found that the they have a nonlinear positive relationship.
作者
刘雅甜
方士正
何松林
李剑楠
刘朕
LIU Yatian;FANG Shizheng;HE Songlin;LI Jiannan;LIU Zhen(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《金属矿山》
CAS
北大核心
2022年第6期46-54,共9页
Metal Mine
基金
国家自然科学基金项目(编号:51934001)。
关键词
铁矿石
SHPB
动载
动态强度
能量耗散
分形维数
iron ore
SHPB
dynamic loading
dynamic strength
energy dissipation
fractal dimension
