Characterisation of secondary fragmentation processes using a combination of laboratory experiments and numerical analysis

制定碎片化模型对于为地雷规划提供可靠的碎片化估计至关重要。该模型需要提供采矿过程中不同阶段预计产生的岩块大小的范围和分布的衡量标准。对于块状和盘状洞穴开采，从采矿点提取的采矿块的大小和形状特别重要，因为生产设备和采矿点布局必须适应所产生的采矿块。在采矿可行性期间评估的破碎预测与在崩落过程中遇到的预测之间的差距突出表明，需要更好地了解二次破碎过程和机制，以促进资源的经济和可持续开采。为了满足这一需求，行业合作伙伴提供了资金和实物支持，以支持不列颠哥伦比亚大学(UBC)的研究，该研究将侧重于将数值分析和实验室实验相结合，以研究在不同载荷条件下与岩石破碎相关的破坏和粉碎过程，这些条件与崩落矿柱中遇到的情况相似。这项研究将使用不同实验室规模的受控实验来校准和约束一系列模拟脆性断裂过程的高级数值分析(使用最先进的FEMDEM代码ELFEN)。这些将被用来开发新的工具和关系，用于表征块状和片状洞穴矿山设计的次生破碎特征。在此基础上，提出了一项为期三年的NSERC合作研究与开发(CRD)赠款，旨在将复杂的数值方法与实验室实验相结合，以提高我们对地下大规模采矿方法的破碎过程及其对安全和经济采矿的贡献的知识。CRD的主要目标将集中在基于地质统计学的离散裂隙网络(DFN)模型、与矿脉密度相关的岩石破碎效率以及模拟结果与实验结果的校准。

The development of a fragmentation model is critical to provide reliable estimates of fragmentation for use in mine planning. The model would need to provide a measure of the range and distribution of the sizes of the rock blocks expected to be produced at various stages during the mining processes. For block and panel cave mining, the size and shape of the blocks extracted from the drawpoints is of particular importance, since the production equipment and the drawpoint layouts must accommodate the resulting blocks. The disparity between fragmentation predictions assessed during mine feasibility and those encountered during caving underscore the need to better understand secondary fragmentation processes and mechanisms to facilitate the economic and sustainable mining of the resource. To address this need, funds and in-kind support have been provided by industry partners to support research at the University of British Columbia (UBC) that will focus on integrating numerical analyses and laboratory experiments to study the failure and comminution processes associated with rock fragmentation under different load conditions that parallel those encountered in a caved ore column. The research will use controlled experiments at different laboratory scales to calibrate and constrain a series of advanced numerical analyses simulating brittle fracture processes (using the state-of-the-art FEMDEM code ELFEN). These will be used to develop new tools and relationships for characterising secondary fragmentation for block and panel cave mine design. Building on this, a three-year NSERC Collaborative Research and Development (CRD) grant is proposed here that will work towards integrating sophisticated numerical methods with laboratory experiments to improve our knowledge of fragmentation processes for underground mass mining methods and its contribution to safe and economic mining. The key objectives of the CRD will focus on geostatistics based Discrete Fracture Network (DFN) models, rock breakage efficiency associated with veins density, and calibration of modelling results with experimental results.