Damage initiation, fracture evolution to failure in deep excavations in structured rock for mining, tunnelling and deep storage - Getting dilation, degradation and structural displacements right for prediction, field verification & observational desi

高水平核废料的处置是所有核电生产国面临的重大工程挑战。深部岩石开挖堆放废物的安全评估主要涉及开挖损伤区(EDZ)的最大范围和该晕圈内的流体流动性。用于公路、铁路、水利、水电、管道布线和资源储存的深部岩石隧道往往涉及在深处接合(自然破裂)的岩体。随着隧道的推进，破坏开始，并演变成隧道工作面和围岩的破坏，以及可能的岩石爆破(剧烈破坏)。在采矿方面，短期的矿石通道和长期的关键基础设施需要隧道。虽然早期的支架设计是基于不稳定岩石载荷和能量释放(岩爆)的计算，但现代设计必须考虑位移潜力和能力。为了支持这三种应用，现代工程模拟工具可以预测深部和高应力条件下均匀、非结构化岩石中的损伤起始和整体屈服程度。作为当前分析的可靠结果，深埋隧道掘进中的屈服后膨胀、空洞产生、体积变化和边界位移的准确表示仍然是难以捉摸的。上述应用之间的共同联系是，需要通过监测施工初始阶段的位移，直至施工孔洞附近岩石内渐进和动态变形的长期演变，来预测和验证。在存在离散结构(节理、静脉)的地方，变形的准确预测和有意义的监测成为一项重大挑战，但为了在这些条件下进行有效和安全的观测设计，必须解决这一问题。这项研究将涉及三个研究环境，包括女王地质力学实验室的力学测试、高级不连续体/连续体建模，以及对过去和当前正在进行的挖掘的评估。12名HQP将通过拟议的研究方案接受培训，培训的基础是过去在挖掘损害研究、支撑分析、长期变形和损害预测、先进建模和最先进监测的关键发展方面的贡献。该DG的研究重点是演化的损伤引起的变形，包括受应力路径、应力和地质构造控制的EDZ的时变和动态响应。关键成果将是以位移为基础的支助设计以及变形反分析和监测的实用指导。其结果将是对结构性脆性岩石中的深层施工进行稳健和智能的观测设计，提高工人的安全性、支撑可靠性和监测有效性。这项工作将在工程评估和设计的可靠性方面产生阶段性变化，降低风险成本，并提高价值数十亿美元的加拿大地下基础设施的项目可行性。

Disposal of high-level nuclear waste is a critical engineering challenge for all countries that generate nuclear power. Safety assessment of deep rock excavations for waste storage is primarily concerned with maximum extent of the excavation damage zone (EDZ) and fluid mobility within this halo. Deep rock tunnelling for roads, rail, water, hydro-power, pipeline routing and resource storage often involves rockmasses that are jointed (naturally fractured) at depth. Damage initiates as the tunnel is advanced and evolves to create tunnel face and wall failure and possible rock-bursting (violent failure). In mining, tunnels are required for short-term ore access and long-term critical infrastructure. While earlier support design was based on calculations of unstable rock load and energy release (rockburst), modern design must consider displacement potential and capacity. In support of these three applications, modern engineering simulation tools can predict damage initiation and overall extent of yield within a uniform, unstructured rockmass in deep and high stress conditions. Accurate representations of the post yield dilation, void generation, bulk volume change and boundary displacement in deep tunnelling remain elusive as reliable outputs from current analysis. The common link between the applications described above is the need to predict and verify through monitoring displacements in the initial stages of construction through to long-term evolution of progressive and dynamic deformations within the rock adjacent to the constructed void. Where discrete structure exists (joints,veins), the accurate prediction and meaningful monitoring of deformations becomes a major challenge, but one that must be solved for effective and safe observational design in these conditions. This research will involve a trifecta of research environments including mechanical testing in the Queen's Geomechanics Lab, advanced discontinuum/continuum modelling, and assessment of past and currently ongoing excavations. 12 HQP will be trained through the proposed research program, building on past contributions in excavation damage research, support analysis, long-term deformation and damage prediction, advanced modelling and key developments in state-of-the-art monitoring. The proposed research for this DG focuses on evolving damage-induced deformation, including time-dependent and dynamic response of EDZ, controlled by stress path,  and geological structure. Practical guidance for displacement-based support design as well as deformation back-analysis and monitoring will be key outcomes. The result will be robust and intelligent observational design for deep construction in structured brittle rock, improving worker safety, support reliability, and monitoring effectiveness. This work will create a step change in reliability of engineering assessments and designs, reducing risk costs and improving project viability for Canadian underground infrastructure worth $Billions.