Abstract: An approximate analytical model has been established in this paper to study dynamic interactions between the saturated soil and the pile group with assumption of poroelastic half-space. The piles are modeled as Bernoulli-Euler elastic beams, and the saturated half-space is governed by Biot’s dynamic equations. The pile beams and the saturated half-space are coupled through receptance matrix established at pile/soil interaction points in frequency-wavenumber domain. Results are obtained by fast Fourier transform. The dynamic impedances of the pile group have been analyzed. Meanwhile, the results demonstrated that the type and frequency of the excitation force and the soil permeability have significant influences on displacement and pore pressure responses of the saturated ground. Especially, it is noted that peak frequencies of pile-foundation impedance increase along with the increasing of soil permeability.

Key words: saturated ground, far-field vibrations, pile-soil interactions, dynamic response, analytical mode