Characterizing behaviour of healed rockmass structures

在具有特别深（约500米）地下开挖和大型露天矿边坡的现代贱金属采矿中，有效的岩体岩土力学特征对于初始开挖和地面支护设计以及在整个项目开发过程中准确预测岩体行为至关重要。由于高预测的全球供需预测、提高的生产率和改善的工人安全，大型露天矿和块状洞穴采矿方法是开发大型矿体的流行方法。采矿业是新不伦瑞克省和加拿大的重要产业；加拿大采矿业在13种主要矿物和金属的全球产量中排名前五。2015年，整个行业为加拿大的GDP贡献了560亿美元。******本研究计划的主要目标是进一步了解岩体结构的愈合元素的行为及其对地下开挖和岩石边坡周围岩体行为的贡献。已愈合的岩体结构，称为块内结构，发生在裂隙边界块体内，否则是完整的岩石，它影响岩体的变形能力和强度。在岩石工程项目的岩土工程调查、表征和分析中，通常不考虑块内结构。然而，在特别深的高应力采矿挖掘中，这些结构已经被观察到通过传统上被认为是完整的岩石或可预测的自然断裂的岩体来控制额外的或延迟的地面破坏的发展。这些意外的地面故障需要额外的地面支持，这增加了工人的安全风险以及项目地面支持成本。随着开挖的继续深入，裂缝对岩体行为的影响将越来越小，但块内结构没有深度限制，对稳定性、安全性和矿山经济性的影响将越来越大。******该研究项目将侧重于块体内部结构的现场检查及其与地面行为的关系，力学特性的实验室分析，并将其集成到岩土工程设计应用的数值模拟中。指导这项研究短期目标的主要主题包括开发一个全面的块内结构数据库，改进岩土数据收集和样品选择方法，对具有块内结构的岩石进行岩土实验室测试，将块体内结构与先进的非连续体数值模型相结合，用于大型露天矿边坡深部破坏和块状溶洞矿山深部开挖周围岩体行为预测。******1名博士，4名硕士和5名URAs将在DG研究计划期间接受培训，并将在工业界和学术界获得大量曝光。

In modern base metal mining featuring particularly deep (>500 m) underground excavations and large open pit slopes, effective geotechnical characterization of the rockmass is critical to the initial excavation and ground support design, and to the accurate prediction of rockmass behaviour throughout project development. Large-scale open pit and block cave mining methods are popular approaches to exploit large orebodies due to the high projected global supply and demand forecasts, increased production rates, and improved worker safety. Mining is a significant industry in New Brunswick and Canada; the Canadian mining industry ranks in the top 5 countries in global production of 13 major minerals and metals. The entire industry contributed $56 billion to Canada's GDP in 2015.******The primary objective of this research program is to gain further understanding of the behaviours of healed elements of rockmass structure and their contributions to rockmass behaviour around underground excavations and rock slopes. Healed rockmass structures, termed intrablock structures, occur within fracture-bounded blocks of otherwise-intact rock, which influence rockmass deformability and strength. Intrablock structures are not conventionally considered during geotechnical investigation, characterization and analysis in rock engineering projects. However, in particularly deep mining excavations at high stress, these structures have been observed to control additional or delayed development of ground failures, through what is traditionally considered to be intact rock, or a predictable, naturally-fractured rockmass. These unexpected ground failures require additional ground support on a reactive basis, which increases the safety risk to workers as well as project ground support costs. As excavations continue to go deeper, fractures will have less influence on rockmass behaviour, but intrablock structures have no depth limit and will have increasing effects on stability, safety, and mine economics.******This research program will focus on the field examination of intrablock structures and their relationship to ground behaviour, laboratory analysis of mechanical properties, and integration into numerical simulations for geotechnical design applications. Major themes to direct the short-term goals of this research include development of a comprehensive intrablock structure database, improvement of geotechnical data collection and sample selection methodologies, geotechnical laboratory testing of rock with intrablock structure, and the integration of intrablock structure into advanced discontinuum numerical models for rockmass behaviour prediction of deep seated failures in large open pit mine slopes and around deep excavations in block cave mines.******1 PhD, 4 MSc and 5 URAs will be trained during this DG research program and will gain significant exposure in industry and academia.