Lateral Vibration of Pile Groups Partially Embedded in Layered Saturated Soils

Abstract

A simplified solution procedure is proposed for estimating the dynamic response of a pile group partially embedded in a layered saturated soil and subjected to horizontal harmonic loading. In the proposed procedure, the transfer matrix method is first applied to solve the vibration equation of a single pile, from which the stiffness of the single pile is obtained. The existing lateral displacement of the saturated half-space is introduced to build the attenuation function, and the balance equation of passive pile is built accordingly. The simple Winkler model is used to derive the dynamic pile-soil-pile interaction factor. Based on the dynamic interaction factor, the horizontal impedance of the pile group is obtained by using the superposition principle. The calculated dynamic interaction factor and impedance of the pile group are in agreement with earlier results for an idealized case, verifying the correctness of the proposed method. The main parameters, such as the embedment ratio, pile separation distance, modulus of the first soil layer, and permeability, are considered in the numerical study, which may provide geotechnical and earthquake engineers with valuable reference for pile foundation design.