Field observation of the wave-induced pore pressure response in a silty soil seabed

Liquefaction of seabed sediments under the action of storm waves is an important form of seabed instability, which may cause damage to submarine structures such as pipelines and cables. A commonly used parameter to identify sediment liquefaction is pore pressure. The pressure response of the pore water at different depths of a silty soil seabed under storm waves was monitored by a probe rod in the Yellow River delta. The probe is made of a steel pipe with a length of 8 m and an outer diameter of 10 cm, which is equipped with 10 pore pressure sensors. According to the collected data, under a water depth of 8 m, silty soil seabed liquefaction starts when the significant wave height reaches 0.5 m, and the liquefaction depth is between 3.3 and 3.8 m under waves with a significant wave height of 3.65 m. Seabed liquefaction develops in a top-down manner, and the average development rate of the liquefaction depth is approximately 0.17 m/min.