Development and validation of a 3-D bonded block modelling approach to assist in the assessment of rock mass bulking and support design for highly stressed mine pillars

随着人口的不断增长和生活水平的不断提高，全世界对矿物资源的需求继续增加。随着近地表资源的枯竭，加拿大等资源丰富的国家正在进行更深层次的开采。加拿大的几个作业已经代表了世界上最深的一些矿山，并计划继续深入。这些工程将包括巨大的地下足迹和众多的岩柱，这些岩柱对于维持安全和经济的工作条件至关重要。面临的挑战是，在开挖过程中，这些支柱将经历显著的应力诱发强度退化和变形，导致支撑系统的广泛负荷，可能导致其破坏。为了满足这些需求，里约热内卢Tinto通过其位于萨德伯里的里约热内卢Tinto地下矿山建设中心（RTC-UMC）提供了研究资金，以(i)调查复杂矿山应力路径下岩体膨胀的潜在机制，（ii）开发可以更好地解释这些机制的数值工具，以及（iii）比较和对比不同支持策略的有效性。为了实现这一目标，我们与软件提供商Itasca合作，使用他们的商用3d独特元素代码3DEC来开发粘结块脆性断裂建模工具，这里称为3DEC- bbm。模型开发将与验证和校准工作同时进行，使用受控的实验室实验和实地数据。一旦完成，这项研究的结果将大大提高加拿大在深部采矿和岩石支护优化方面的知识和专业知识。将开发新工具（连同其使用准则），协助工程师设计和安全开发下一代加拿大矿山，帮助确保该工业的可持续性。它还将为HQP提供独特和实用的学习经验和技能，这些经验和技能在采矿业中需求量很大，对加拿大未来的自然资源开发需求具有战略重要性。

With ever growing populations and rising living standards, worldwide demand for mineral resources continues to increase. Resource-rich countries like Canada are responding by mining deeper as near surface resources are exhausted. Several Canadian operations already represent some of the deepest mines in the world, and plans are to continue deeper. These will encompass large underground footprints with numerous rock pillars that are essential for maintaining safe and economic working conditions. The challenge is that during excavation, these pillars will experience significant stress-induced strength degradation and deformation leading to extensive loading of the support system, potentially leading to its failure. To address these needs, Rio Tinto through their Sudbury based Rio Tinto Centre for Underground Mine Construction (RTC-UMC), have provided research funding to (i) investigate the underlying mechanisms of rock mass bulking under complex mine stress paths, (ii) develop a numerical tool that can better account for these mechanisms, and (iii) compare and contrast the effectiveness of different support strategies. Towards this goal we have partnered with software provider Itasca to use their commercial 3-D distinct-element code 3DEC to develop a bonded-block brittle fracture modelling tool, referred to here as 3DEC-BBM. Model development will be carried out in parallel with validation and calibration exercises, using both controlled laboratory experiments and field-based data. Upon completion, the results of this research will significantly enhance Canada's body of knowledge and expertise in deep mining and rock support optimization. New tools will be developed (together with guidelines on their use) that will assist engineers in designing and safely developing the next generation of Canadian mines, helping to secure the sustainability of the industry. It will also provide HQP with unique and practical learning experiences and skill sets that are in high demand in the mining industry and are of strategic importance for Canada's future natural resource development needs.