Mechanical Response of Suction Anchors During Suction-Assisted Penetration in Layered Soils Based on the Material Point Method (MPM)

Suction anchors are widely used in offshore wind power foundations, where their penetration behavior critically influences installation efficiency and safety. Existing studies mainly focus on homogeneous soils, while the mechanisms of suction-assisted penetration in layered seabed remain less understood. This study establishes a numerical model based on the Material Point Method (MPM) to simulate suction anchor penetration in saturated soils, accounting for large deformations and hydro-mechanical coupling. The model is validated against physical tests, confirming the reliability of MPM. A series of simulations is conducted to examine penetration behavior under layered conditions, emphasizing the effects of stratigraphic sequence and configuration, including sand-over-clay (SC), clay-over-sand (CS), sand–clay–sand (SCS), and clay–sand–clay (CSC) profiles. The analysis reveals complex mechanical responses during penetration, including excess pore water pressure, soil displacement, effective stress, and penetration resistance. The results demonstrate that penetration behavior is governed by both the stratification sequence and the number of soil layers. Overall, this study clarifies the complex mechanical responses of suction caissons in layered soils, verifies the suitability of MPM for simulating large-deformation and hydro-mechanical coupling problems, and provides insights for the design and safe installation of suction caissons in stratified seabeds.