Quantification of blasting parameters and the relationship to heterogeneous and anisotropic nature of jointed rock masses

在采矿作业中，通常使用钻孔和爆破来破碎岩石。不同的参数会影响岩体对爆炸能量的响应，从而影响岩石的破碎效果。这些参数包括岩体的物理和地质力学性质、炸药的性质、爆炸设计、时间等值线和爆炸的边界条件。由于这些参数之间的复杂相互作用，准确预测爆炸诱发的岩石破碎一直是一个具有挑战性的问题。此外，在窄矿脉露天矿，矿化以断层或剪切赋存的窄矿脉的形式出现，台阶爆破会导致矿石过度损失和贫化。 任何爆破引起的岩石破碎和爆破引起的矿石损失/贫化的改善都需要对岩石的非均质性和各向异性有很好的了解。组成节理岩体的原地岩块和完整岩桥的大小和形状分布对块度和爆破性能有重要影响。本研究旨在研究岩石地质力学性质的空间变异性和各向异性对其爆炸响应的影响。在这个研究项目中，现场和实验室数据将从位于安大略省北部的德图尔湖露天矿收集。这包括绘制不同岩体域的节理网络图、测量完整的岩石性质、记录当前的爆破设计、矿井使用的炸药类型等。此外，还将在不同岩体域的矿场进行爆破运动监测，以测量爆炸引起的岩石运动。收集到的数据将经过详细的统计分析，以更好地了解岩石性质与其在爆破过程中的行为之间的关系。这一结果将有助于开发替代战略，以减少和控制矿石损失和贫化，同时改善岩石破碎程度。总体而言，这将对露天矿规划的经济和技术方面产生非常积极的影响。

In mining operations, drilling and blasting are commonly used for rock fragmentation. Different parameters can influence the response of rock masses to blasting energy and consequently the rock fragmentation results. These parameters include physical and geomechanical properties of rock masses, properties of explosives, blast design, timing contours and boundary conditions of the blast. Accurate prediction of blast-induced rock fragmentation has remained a challenging issue due to the complex interaction between these parameters. In addition, in narrow vein open pit mines, where the mineralization occurs in the form of fault or shear hosted narrow veins, bench blasting can result in excessive ore loss and dilution. Any improvement in blast-induced rock fragmentation and blast-induced ore loss/dilution requires a good understanding of rock mass heterogeneity and anisotropy. The size and shape distribution of the in-situ rock blocks and intact rock bridges that make up a jointed rock mass have an important influence on fragmentation and blasting performance. This research project aims to investigate the effect of spatial variability and anisotropy of rock mass geomechanical properties on their response to explosive action. In this research project field and laboratory data will be collected from the Detour Lake open pit mine located in northern Ontario. This includes mapping of the joint networks in different rock domains, measurement of intact rock properties, recording current blast design, type of explosives used at the mine, etc. In addition, blast movement monitoring will be carried out at the mine site for different rock mass domains to measure the blast-induced rock movement. The collected data will be subjected to a detailed statistical analysis to better understand the correlation between rock mass properties and their behaviour during blasting. The results would allow development of alternative strategies to reduce and control ore loss and dilution while improving rock mass fragmentation. Overall, this will have a very positive impact on the economic and technical aspect of open pit mine planning.