Numerical analysis for isolation of vibrations by pile rows in transversely isotropic saturated media due to moving loads

Abstract

An analytical layer-element–boundary-element coupling approach is presented to explore the isolation effect of pile rows in stratified transverse isotropic saturated media for moving-load induced vibration. The analytical layer-element basic solution for the soils is derived. The soil flexibility matrices are obtained using boundary integral equations for pile-soil. Then, the pile is modeled as a Bernoulli–Euler beam utilizing the finite difference approach. The dynamic equations for the piles are achieved by considering the pile-soil displacement coordination condition. Finally, to obtain the amplitude reduction ratio, the displacement of an observation point is calculated with and without pile isolation, respectively. The results are in good consistency with the existing solutions. The impacts of the soils’ transverse isotropy, the pile’s size and physical properties on the isolation effect are evaluated using numerical examples. It is observed that when the pile length exceeds a certain value, the increment in the pile length shows no obvious improvement in the vibration isolation effect. A stiffer pile has a greater impact on vibration reduction. The material anisotropy is also an important parameter for the pile isolation problem.