Hydro-Mechanical Interfacial Behavior of Offshore Foundations Under Uplift Loading

Anchoring systems for deep-water floating structures must withstand complex, hydro-mechanical (H-M) coupled uplift forces throughout an operational life extending over decades, yet fundamental understanding of this complicated H-M behavior remains insufficient. This paper presents a comprehensive review of H-M coupled foundation–seabed interactions under uplift loading. Key experimental findings are synthesized to demonstrate that the fundamental distinction between uplift and compression lies in the foundation-soil interface. Unique interfacial uplift behaviors are highlighted, including the progressive formation of an interfacial gap and the evolution of transient suction within it. This water-filled gap enables sustained tensile contact stress post-detachment, transforming traditional soil-structure interaction to the more general “soil–interfacial fluid–structure” interaction framework. A 1D conceptual model, representing a mechanistic extension of Terzaghi’s consolidation theory, is discussed to further elucidate these H-M mechanisms. For complex 3D numerical simulations, the limitations of traditional total-stress interface models are discussed, and specialized H-M thin-layer and zero-thickness interfaces designed for uplift modeling are critically examined regarding their advantages and limitations. The review concludes by outlining a roadmap for the next research frontier: high-fidelity treatments of sustained multidirectional cyclic loading, suction-induced liquefaction, and the long-term rheological evolution of the interface.