Multiphysics of Fluid-Saturated Geomaterials and Chemically Damaged Barriers

流体饱和岩土材料和化学损伤屏障的多物理场

• 批准号: RGPIN-2016-04676
• 负责人: Selvadurai, Antony
• 金额: $ 4.37万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=709429
• 关键词: Multiphysics; Fluid; Saturated; Geomaterials; Chemically

This research will develop innovative experimental techniques and theoretical models of coupled processes in geomaterials and implement the approaches in computational schemes that can examine and predict the outcome of geologic disposal and containment strategies important to energy resources recovery, nuclear waste management, geologic sequestration of greenhouse gases and geothermal energy extraction. The role of multiphysics couplings needs to be understood in the context of the interaction of thermal (T), hydraulic (H), mechanical (M) and chemical (C) processes. The emphasis of the research program is to achieve the necessary advances in theoretical, computational and experimental procedures that have immediate applications to geoenvironmental protection strategies. The highly heterogeneous Cobourg Limestone, targeted by the Nuclear Waste Management Organization, ON, for deep geological storage of radioactive wastes, will be studied using large cylindrical samples (150 mm dia., 300 mm long). The internal features of the rock present a challenge in terms of multi-scale coupled processes and for this reason, experiments will be performed using the recently acquired Triaxial Cell with Acoustic Emission Tomography mapping capabilities, to progressively track defect evolution that will affect the THM responses. This equipment is unique to Canada. Using the experimental results, reliable models of the THM behaviour of Cobourg Limestone will be achieved to predict the long-term scenarios of NWMO initiatives. The research will also examine THMC effects in geologic storage of CO2 in carbonate reservoirs since the targeted storage horizons in Canada are largely carbonate rocks. Preliminary studies reveal that wormholes or dissolution channels develop rapidly in carbonate-rich samples; this will affect the storage potential of the aquifer and compromise the structural support that provides stability for caprock barriers. Storage rocks from Weyburn, SK, Brooks, AB and Bécancour, QC will be tested and models developed to relate chemical erosion at fractures and sealing interfaces to alterations in geostatic stress states and carbonate content. Research will also address the role of chemicals on the mechanics of geosynthetics, particularly their embrittlement due to plasticizer removal, and examine the stress-assisted transport of chemicals in geomembranes leading to anisotropic effects. Rate-sensitive constitutive models will be developed; these could be used to predict tearing failure at defects, at connecting seams and, in particular, the localized regions of action of chemicals such as ethanol. Over the next five years, the research program will train PDFs, PhDs, Masters and UG students, with skills to effectively contribute to these areas. The projects will have a significant impact on the development of policy for the protection of the environment.

这项研究将开发创新的实验技术和地质材料耦合过程的理论模型，并在计算方案中实施方法，这些方法可以检查和预测地质处置和遏制战略的结果，这些战略对能源资源回收，核废物管理，温室气体的地质封存和地热能开采至关重要。多物理场耦合的作用需要在热（T），水力（H），机械（M）和化学（C）过程相互作用的背景下理解。该研究计划的重点是在理论，计算和实验程序方面取得必要的进展，这些程序可以直接应用于地质环境保护战略。 将使用大型圆柱形样品（直径150 mm，300 mm长）。岩石的内部特征在多尺度耦合过程方面提出了挑战，因此，将使用最近获得的具有声发射断层成像映射功能的三轴单元进行实验，以逐步跟踪将影响THM响应的缺陷演变。这种设备是加拿大独有的。使用实验结果，可靠的模型的THM行为的科布尔石灰石将实现预测的长期方案的NWMO倡议。 该研究还将研究THMC对碳酸盐岩储层中CO2地质储存的影响，因为加拿大的目标储存层主要是碳酸盐岩。初步研究表明，虫孔或溶解通道在富碳酸盐岩样品中迅速发展;这将影响含水层的储存潜力，并损害为盖层屏障提供稳定性的结构支撑。将对来自韦伯恩、SK、布鲁克斯、AB和Bécourour、QC的储层岩石进行测试，并开发模型，以将裂缝和密封界面处的化学侵蚀与地质静态应力状态和碳酸盐含量的变化联系起来。 研究还将解决化学品对土工合成材料力学的作用，特别是由于增塑剂去除而导致的脆化，并检查土工膜中化学品的应力辅助运输导致各向异性效应。率敏感的本构模型将被开发，这些可用于预测撕裂故障的缺陷，在连接接缝，特别是，局部区域的化学品，如乙醇的行动。 在接下来的五年里，该研究计划将培训PDF，博士，硕士和UG学生，并掌握有效促进这些领域的技能。这些项目将对环境保护政策的制定产生重大影响。