The instantaneous seabed liquefaction around offshore pile-type foundation and seabed protection under combined wave and current loading

The physical processes involved in the wave-seabed-mono-pile interactions are rather complex, and its upper and lower structures are affected by different loads. This paper presents the application of a three-dimensional numerical model, which was validated with the laboratory experiments available in the literature. First, the soil response induced by the combined wave and current around a mono-pile is discussed, and then the stability of the pile foundation is further evaluated. Numerical examples demonstrate the wave run-up and the distribution of seabed liquefaction around piles are closely related to characteristics of ocean currents. Meanwhile, for the pile group system, the hydrodynamic and dynamic seabed response characteristics are regarded as a function of pile group layout, which will affect the development of the near-trapping phenomenon under the combined wave-current loading. Furthermore, the application of protection mattresses around the pile group is proven to be an effective option for reducing the potential of seabed liquefaction, which is not considered in previous studies.

Automated summary

This paper presents a study on the physical processes involved in wave-seabed-mono-pile interactions using a three-dimensional numerical model. The study finds that the characteristics of ocean currents have a significant impact on wave run-up and the distribution of seabed liquefaction around piles. Additionally, the layout of the pile group affects the development of the near-trapping phenomenon. The study also suggests that using protection mattresses around the pile group is an effective option for reducing the potential of seabed liquefaction, which has not been considered in previous studies.