Abstract: In order to investigate the influence of main parameters of pile and soil on the lateral vibration of pipe pile in saturated soil, the soil is divided into saturated soil around pile and inner pile saturated soil, and coupling dynamic model of the saturated soil-pipe pile is established by using the control equations of theory of porous medium. By considering the boundaries of saturated soil around pile and inner pile saturated soil, the lateral vibrations of saturated soil around pile and inner pile core saturated soil are solved with the uncoupling method of potential function. The horizontal vibration of pipe pile in saturated soil is also solved by considering the forces of saturated soil around pile and inner pile saturated soil acting on pipe pile, and the lateral dynamic impedance of the pipe pile at pile head is obtained; the influence of main parameters on the lateral vibration of pipe pile in saturated soil is also analyzed. The research results indicate that the influence of the inner and outer radii of pipe pile, shear modulus ratio, Poisson’ ratio of pile around saturated soil and pile core saturated soil on the lateral dynamic impedance of pipe pile in saturated soil is great; fluid-solid coefficient ratio has a certain influence on lateral dynamic impedance at low frequency; and the ratio of damping ratio has a certain influence on the damping factor of lateral dynamic impedance.

Key words: saturated soil, pipe pile, lateral vibration, dynamic impedance, shear modulus