Critical state soil constitutive model for methane hydrate soil

作者：Shun Uchida, Kenichi Soga, Koji Yamamoto · 发表于：Journal of Geophysical Research Atmospheres · 年份：2012 · DOI：10.1029/2011jb008661 · 被引用次数：286 · 研究领域：Methane Hydrates and Related Phenomena、Climate change and permafrost、CO2 Sequestration and Geologic Interactions

This paper presents a new constitutive model that simulates the mechanical behavior of methane hydrate‐bearing soil based on the concept of critical state soil mechanics, referred to as the “Methane Hydrate Critical State (MHCS) model”. Methane hydrate‐bearing soil is, under certain geological conditions, known to exhibit greater stiffness, strength and dilatancy, which are often observed in dense soils and also in bonded soils such as cemented soil and unsaturated soil. Those soils tend to show greater resistance to compressive deformation but the tendency disappears when the soil is excessively compressed or the bonds are destroyed due to shearing. The proposed model represents these features by introducing five extra model parameters to the conventional critical state model. It is found that, for an accurate prediction of ground settlement, volumetric yielding plays an important role when hydrate soil undergoes a significant change in effective stresses and hydrate saturation, which are expected during depressurization for methane gas recovery.