Coupled processes in environmental geomechanics: theoretical, computational and experimental modelling

环境地质力学是解决地质环境问题的关键学科，它具有复杂的力学、物理和化学相互作用，深刻地影响着地质材料行为的模拟。发现补助金的基本主题涉及材料中的热-水-机械-化学（THMC）耦合，并侧重于以下方面：（i）化学界面及其对废物容纳中使用的土工合成屏障的力学和完整性的影响，（iii）地质材料中易受化学损害的THMC过程，应用于CO2的地质储存，以及（iii）多孔岩石中的耦合THM过程，特别涉及流体运输过程中的热诱导水力滞后。这些专题对影响人类健康和环境的地质环境工作至关重要，特别是因为它们涉及到遏制来自尾矿和填埋场的有毒废物、在盐水层和酸性矿井排水中地质固存二氧化碳以及在地质深处储存高放热核燃料废物。该研究涉及模型开发、实验室实验和计算建模，可以被视为全面实地调查的必要前奏。计算模型的开发及其通过实验的验证是有科学依据的，是至关重要的，特别是当替代方案涉及昂贵的现场规模测试，缺乏足够的定义模型开发。考虑到与许多遏制战略有关的时间尺度，计算方法是必要的：例如，核废物隔离所涉及的时间尺度大约为10，000年，而废物沥出液和有毒材料的储存和遏制以及二氧化碳的地质固存必须被视为永久性的。发现补助金将培养环境地质力学家，对实验研究和复杂建模的重要性（和局限性）保持平衡，并为加拿大和国际上的科学，工程和监管界提供资产。

Environmental geomechanics is the key discipline for solving geoenvironmental problems that have complex interactions between mechanics, physics and chemistry, which profoundly influences the modelling of geomaterial behaviour. The underlying theme of the Discovery Grant relates to Thermo- Hydro- Mechanical- Chemical(THMC) coupling in materials and focuses on the following:(i) Chemical interfaces and their influence on the mechanics and integrity of geosynthetic barriers used in waste containment, (iii) THMC processes in geomaterials susceptible to chemical damage with applications to geologic storage of CO2, and (iii) Coupled THM processes in porous rocks with special reference to heat-induced hydraulic hysteresis in the fluid transport processes. These topics are critically important to geoenvironmental endeavours, which has an impact on human health and the environment, particularly as they relate to containment of toxic wastes derived from mine tailings and landfill, geologic sequestration of CO2 in saline aquifers and acid mine drainage and the deep geologic storage of high-level heat-emitting nuclear fuel wastes. The research involves model development, laboratory experimentation and computational modelling and can be viewed as a necessary prelude to full-scale field investigations. Computational model development and their validation by recourse to experiments is well founded in the scientific method and is vital, particularly when the alternative involves costly field scale tests that lack sufficient definition for model development. Computational approaches are necessary in view of time scales relevant to many containment strategies: e.g. the time scales of interest to nuclear waste isolation are of the order of 10,000 years, while storage and containment of leachate and toxic materials from wastes and geologic sequestration of CO2 have to be regarded as permanent. The Discovery Grant will train environmental geomechanicists with a balanced outlook on the importance (and limitations) of experimental research and sophisticated modelling, and an asset to scientific, engineering and regulatory communities in Canada and internationally.