The study investigates the dynamic response characteristics of offshore large-diameter pipe piles in layered seabed soil under horizontal dynamic loading

considering the interaction between pipe piles

seawater

and layered seabed soil. Seawater is treated as an inviscid compressible medium to establish the motion equations of outer and inner seawater. The hydrodynamic pressure of outer and inner seawater acting on the offshore pipe piles is derived using the separation variable method and combined with the boundary conditions. The seabed soil is considered as a viscoelastic medium

and its layered nonhomogeneity is simultaneously taken into account. The horizontal resistances of outer and inner seabed soil acting on the pipe piles are derived using the differential variation method in conjunction with the vibrational boundary conditions. The governing equation of the pipe pile is established based on the balance of horizontal force on each pile section. The analytical solution of the horizontal dynamic response of offshore large-diameter pipe piles in layered seabed soil is derived using the transfer matrix method and combined with the continuity condition of pile piles and the boundary conditions of pile head and bottom. Analytical expression of pile head displacement is also obtained. The proposed solution’s results are validated against FEM numerical results and existing analytical solutions to verify its rationality. Finally

based on the presented solution

the sensitivity of the horizontal dynamic responses of the pipe pile-water-layered soils system to certain key parameters

such as hydrodynamic pressure

water depth

soil modulus

and soil layer thickness

is analyzed.