紫金山金铜矿爆破孔网参数优化模拟研究

Simulation Study on Optimization of Blasting Hole Pattern Parameters in Zijinshan Gold and Copper Mine

台阶爆破是露天采矿的重要环节,其爆破效果直接影响到后续铲装运输的效率,爆破设计、岩石性质、地质构造等因素均对爆破效果有较大影响。为减少底根和大块,提高爆破效果,以紫金山铜矿9号溜井降段工程为依托,进行爆破参数的优化模拟研究。通过试验确定了岩石的力学参数,通过LS-DYNA软件建立了3组不同孔网参数的爆破模型,观察起爆过程的应力云图并分析被爆岩石的应力响应,得出裂纹区内岩石所受的峰值拉应力是其发生破碎的主导作用。之后结合岩石破碎理论,逐一分析了不同孔网参数下被爆岩石的峰值拉应力,并同岩石的动态抗拉强度做对比,来判断其破碎效果,得出了最优的孔网参数。通过数值模拟优化及现场试验,爆破效果得到了明显改善,铲装运输效率也大大提升,此模型可为类似爆破工程的孔网参数优化提供参考。

Bench blasting is an important link in open pit mining.Its blasting effect directly affects the efficiency of subsequent shovel loading and transportation.Blasting design,rock properties,geological structure and other factors have a great impact on the blasting effect.In order to reduce the root and large blocks and improve the blasting effect,the optimization simulation study of blasting parameters is carried out based on the No.9 pass lowering project in Zijingshan Gold and Copper Mine.The mechanical parame⁃ters of the rock were determined through experiments.Three groups of blasting models with different hole mesh parameters were established through LS-DYNA software.The stress nephogram of the initiation pro⁃cess was observed and the stress response of the blasted rock was analyzed.It was concluded that the peak tensile stress of the rock in the crack zone was the dominant role in its fragmentation.Then combined with the rock fragmentation theory,the peak tensile stress of the blasted rock under different hole network param⁃eters is analyzed one by one,and compared with the dynamic tensile strength of the rock to judge its frag⁃mentation effect,and the optimal hole network parameters are obtained.Through numerical simulation opti⁃mization and field test,the blasting effect has been significantly improved,and the efficiency of shovel load⁃ing and transportation has also been greatly improved.This model can provide a reference for the optimiza⁃tion of hole network parameters in similar blasting projects.