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

用于采矿、隧道开挖和深部存储的结构岩石深部开挖中的损伤萌生、断裂演化到失效 - 正确预测膨胀、退化和结构位移，进行现场验证

• 批准号: RGPIN-2022-03052
• 负责人: Diederichs, Mark
• 金额: $ 6.41万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754986
• 关键词: Damage; initiation; fracture; evolution; failure

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.

高放射性核废料的处置是所有核能发电国家面临的一项重大工程挑战。废物储存的岩石深开挖的安全评估主要涉及开挖破坏区（EDZ）的最大范围和该晕内的流体流动性。用于公路、铁路、水利、水电、管道路由和资源储存的深岩隧道通常涉及在深度处节理（自然断裂）的岩体。损坏随着隧道的推进而开始，并发展成隧道面和壁的破坏以及可能的岩爆（剧烈破坏）。在采矿中，隧道需要用于短期矿石通道和长期关键基础设施。早期的支护设计是基于不稳定岩石载荷和能量释放（岩爆）的计算，而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在深层和高应力条件下均匀的非结构化岩体内的损伤起始和总体屈服程度。从目前的分析中，屈服后膨胀，空洞的产生，体积变化和边界位移在深隧道的准确表示仍然难以捉摸的可靠输出。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来预测和验证，直到施工空隙附近岩石内渐进和动态变形的长期演变。在存在离散结构（节理、矿脉）的情况下，准确预测和有意义的变形监测成为一个重大挑战，但必须解决这些条件下有效和安全的观测设计。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机械测试，先进的不连续/连续建模，以及对过去和目前正在进行的挖掘的评估。12名HQP将通过拟议的研究计划接受培训，建立在过去在挖掘损伤研究，支撑分析，长期变形和损伤预测，先进建模和最先进监测的关键发展方面的贡献。该DG的拟议研究重点是不断发展的损伤诱导变形，包括时间依赖性和动态响应的EDZ，控制应力路径，和地质结构。对基于位移的支护设计以及变形反分析和监测的实际指导将是关键成果。其结果将是结构性脆性岩石中深部施工的稳健和智能观测设计，提高工人安全性，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创造一个台阶，降低风险成本，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。