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，世界范围内对矿产资源的需求不断增加。随着近地表资源枯竭，加拿大等资源丰富的国家正在采取更深层次的开采。加拿大的几个业务已经代表了世界上一些最深的矿井，并计划继续进行更深的开采。这些将包括巨大的地下足迹和大量的岩柱，这对于保持安全和经济的工作条件是必不可少的。挑战在于，在开挖过程中，这些支柱将经历严重的应力引起的强度退化和变形，导致支撑系统承受广泛的载荷，可能导致其失效。为了满足这些需求，力拓通过其位于萨德伯里的力拓地下矿山建设中心(RTC-UMC)提供了研究资金，以(I)调查复杂矿压路径下岩体膨胀的根本机制，(Ii)开发能够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3-D独特元素代码3DEC来开发粘结-块状脆性断裂建模工具，这里称为3DEC-BBM。模型的开发将与验证和校准工作同时进行，使用受控实验室实验和实地数据。完成后，这项研究的结果将大大增强加拿大在深部采矿和岩石支持优化方面的知识和专业知识。将开发新的工具(以及它们的使用指南)，以帮助工程师设计和安全开发下一代加拿大矿山，帮助确保行业的可持续性。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很高，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.