Influence of Fracture Heterogeneity on Rock Deformation and Failure (INFORM): A Mechanics-based Multi-scale Framework for Radioactive Waste Disposal

裂缝非均质性对岩石变形和破坏的影响（INFORM）：基于力学的放射性废物处置多尺度框架

• 批准号: EP/W031221/2
• 负责人: Junlong Shang
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FW031221%2F2
• 关键词: Influence; Fracture; Heterogeneity; Rock; Deformation

Nuclear power is low-carbon and green energy. It presently provides about 10% of the world's electricity and 20% of the UK's electricity, contributing enormously to global Net Zero emissions. Nuclear power will continue to play an important role in the global transition to a low carbon economy. However, one major disadvantage of nuclear power is that its generation process produces radioactive waste that can remain hazardous for hundreds of thousands of years. Over the past more than 60 years' utilisation of nuclear power in the UK and worldwide, many radioactive wastes have accumulated, most of which are stored temporarily in storage near nuclear power plants. It is vital for us to deal with the waste to protect human health and the environment. A global consensus has been reached in this area, that is to isolate radioactive waste that is incompatible with surface disposal permanently in suitable underground rock formations (i.e., host rocks) by developing a geological disposal facility (GDF). As also set out in the 2014 White Paper, the UK Government is committed to implementing geological disposal, with work on developing this led by Radioactive Waste Management Ltd (RWM). Developing a GDF relies on a stable rock formation to ensure mechanical stability and barrier function of host rocks. It is therefore essential to understand factors that influence the integrity of rocks. This is challenging partially because of the complexity of rock fractures that are widespread in the Earth upper crust. Although rock mechanical behaviour has a long record of study, attempts to understand the role of fractures on rock deformation still has unresolved issues. For example, natural rock fractures are often dealt with crudely; almost all previous studies of this problem assume rock fractures to be continuous, with zero or very small cohesion that can be neglected. However, it is almost a ubiquitous feature that natural rock fractures in the subsurface are incipient and heterogeneous, with considerable tensile strength and cohesion. This is either due to secondary minerals having recrystallised, bonding fracture surfaces together, or due to rock bridges.This INFORM project will focus on mineral-filled fractures (i.e., veins) that are frequently seen in the subsurface but often ignored or less researched so far. The aim of INFORM is to increase confidence in the design, construction, and operation of GDFs, by developing a mechanics-based multi-scale framework to understand the influence of fracture heterogeneity on the integrity and deformation behaviour of rocks across scales. The framework will integrate imaging analysis, laboratory experiments, numerical modelling, and field observations, to (1) determine factors contributing to fracture heterogeneity across scales, (2) understand the shear and triaxial deformational behaviour of veined rocks considering natural fracture geometry and heterogeneity, and (3) develop a field-scale model for repository structures considering fracture heterogeneity. Unlike most previous studies, which have focused on the influence of mechanical fractures on rock behaviour, INFORM will for the first time investigate the influence of natural veins, and will consider and implement these observations in the modelling of veined rock behaviour applied to a GDF. INFORM will "inform" a wide range of audiences with new insights through correlating micro-scale observations and macro-scale deformation of heterogenous veined and fractured rocks. This will be possible with the strong support of our academic and industrial partners (RWM, UK; Jacobs, UK; Northeastern University, China; GFZ, Germany; Stanford University, USA) and the help of our well-designed outreach and publication plans. INFORM will lead to a more accurate and reliable examination of fracture heterogeneity, which will not only directly benefit GDF R&D, but also broader rock engineering applications (e.g., tunnelling, cavern construction).

核能是低碳和绿色能源。目前，它提供了世界上约10％的电力和20％的英国电力，造成了全球净零排放量的巨大贡献。核电将继续在向低碳经济的全球过渡中发挥重要作用。但是，核能的一个主要缺点是其产生的过程产生了可危害数十万年的放射性废物。在过去的60多年来，在英国和全球范围内利用了核电，许多放射性废物都积累了，其中大多数是临时存储在核电站附近的存储中。对于我们处理保护人类健康和环境的废物至关重要。在该领域达成了全球共识，即通过开发地质处理设施（GDF），将与表面处置不相容的放射性废物隔离在合适的地下岩层（即宿主岩石）中永久性地处置。正如2014年白皮书中所述，英国政府致力于实施地质处置，并以放射性废物管理有限公司（RWM）为首的开发这种处理。开发GDF取决于稳定的岩石形成，以确保宿主岩石的机械稳定性和屏障功能。因此，了解影响岩石完整性的因素至关重要。这是一个挑战，部分原因是岩石裂缝的复杂性在地球上皮中广泛。尽管岩石机械行为具有很长的研究记录，但试图了解裂缝对岩石变形的作用的尝试仍然存在尚未解决的问题。例如，天然岩石裂缝经常被粗鲁地处理。几乎所有关于此问题的研究都认为岩石骨折是连续的，可以忽略零或很小的内聚力。然而，几乎是无处不在的特征，地下中的天然岩石断裂是初期和异质性的，具有相当大的拉伸强度和内聚力。这要么是由于二级矿物质重结晶，粘结裂缝表面在一起，要么是由于岩石桥。此信息项目将集中于矿物质裂缝（即静脉），这些裂缝（即静脉）经常在地下，但经常被忽略，或者经常被忽略或更少的研究。告知目的是通过开发基于机械的多规模框架来了解裂缝异质性对跨尺度岩石的完整性和变形行为的影响，以提高GDF的设计，构建和操作的信心。该框架将整合成像分析，实验室实验，数值建模和现场观察结果，以（1）确定有助于跨尺度上断裂异质性的因素，（2）了解脉络岩石的剪切和三方变形行为，考虑自然断裂几何形状和（3）型号的模型的自然断裂几何形状和（3）的结构模型。与大多数侧重于机械裂缝对岩石行为的影响的研究不同，Infors将首次研究自然静脉的影响，并将考虑并实施这些观察结果，以在应用于GDF的脉络岩石行为的建模中。通过将微观观测和异质脉和破裂岩石的宏观变形相关联，信息将“告知”广泛的观众，并通过新见解。在我们的学术和工业伙伴（英国RWM；英国雅各布；中国东北大学；德国GFZ；美国斯坦福大学）和我们精心设计的宣传和出版计划的帮助下，这将是可能的。信息将导致对断裂异质性的更准确，更可靠的检查，这不仅会受益于GDF研发，而且还会受益于更广泛的岩石工程应用（例如，隧道，洞穴建设）。