Anisotropy is an inherent characteristic of subgrade soils, causing significant variations in the dynamic behavior of the pile embedded in them under different loading conditions. This research develops a novel model to examine, for the first time, the dynamic behavior of an end-bearing pile embedded in an anisotropic elastic medium subjected to vertical S-waves. The pile is modeled as a Euler-Bernoulli beam, while the surrounding soil is treated as a transversely isotropic (TI) elastic material. The one-dimensional free-field and three-dimensional scattered-field motions in the TI elastic medium under S-waves are obtained within the frame of dynamic continuum model. The developed model is checked for accuracy against established analytical solution. Key parameters, such as the anisotropic modulus ratio of the TI soil, pile radius, are systematically studied to assess their effects on the kinematic behavior of the system. Results reveal that the soil anisotropy would significantly alter the kinematic behavior of the pile and surrounding soil system, notably impacting the amplification factors for pile displacement and rotation and the horizontal movement of the soil. These findings highlight the necessity of considering soil anisotropy in the seismic design and analysis of pile foundations to ensure structural safety and performance under earthquake.

The S-wave velocity (Vs) is a valuable parameter for assessing the mechanical properties of subsurface materials for geotechnical purposes. Seismic surface wave methods have become prominent for estimating near-surface Vs models. Researchers have proposed methods based on passive seismic signals as efficient alternatives to enhance depth of investigation, lateral resolution and reduce field effort. This study presents the Multichannel Analysis of Surface Waves (MASW) utilizing Common Virtual Source Gathers (CVSGs) derived from seismic ambient noise cross-correlations, based on Ambient Noise Seismic Interferometry concepts. The method is applied to passive data acquired with an array of receivers at the Paranoa earth dam in Brasilia, Brazil, to construct a pseudo-2D Vs image of the massif for interpretation. Our findings showcase the adopted processing flow and combination of methods as an effective approach for near-surface Vs estimation, demonstrating its usability also for large earth dam embankments.