Development of Micromechanically-Based Models for Unsaturated Geomaterials

与基础设施、能源和环境相关的新兴地质力学问题对岩土工程的基本原则提出了挑战。例如，不饱和，热和耦合条件的分析要求超越传统的理论，主要是现象学的性质。在最简单的情况下，不饱和是指存在多于一种流体，例如通过孔隙空间内的界面分离的液体和气体。这导致了非饱和介质的行为与干燥或完全饱和的情况有很大的不同。事实上，不饱和度赋予介质表观内聚性、更高的强度和刚度，其是水分和温度的函数。这种强度的增加在变化的水力和热负荷下，如气候波动或气体条件下，是短暂的。因此，强度可能会迅速丧失，导致地质结构的自发坍塌故障。

Emerging geomechanics problems associated with infrastructure, energy and the environment present challenges to basic tenets of geotechnical engineering. For instance, unsaturated, thermal and coupled conditions demand analyses that go beyond traditional theories which are mostly phenomenological in nature. Unsaturation in the simplest case refers to the presence of more than one fluid, e.g. liquid and gas separated by interfaces within the pore space. This results in the behaviour of an unsaturated medium being vastly different from the dry or fully saturated case. In fact, unsaturation confers the medium with an apparent cohesion, a higher strength and stiffness that are a function of moisture and temperature. This gain in strength is evanescent under varying hydraulic and thermal loads such as climatic fluctuations or gassy conditions. As such, strength could be rapidly lost causing spontaneous collapse failures in geostructures.