Theoretical modeling of a vibrator–ground coupled dynamic interaction system and its vibration characteristics

The demand for the seismic vibrator in land exploration has increased, and a more refined model that could capture the coupled vibration dynamics of the vibrator–ground interaction system is urgently required. In this paper, an improved vibrator–ground coupled dynamics (VGCD) model is newly proposed with consideration of the coupling effects of near-source area and nonlinear baseplate–earth interaction. The partial differential equations of the VGCD model are discretized by utilizing the Galerkin method. After verifying the convergence and solution of the proposed model, the comprehensive comparisons of the dynamic response of the VGCD interaction system with the traditional models are presented to reveal the effects of coupled ground on the vibrator dynamics. Moreover, a systematical parametric study is conducted to investigate the effects of the ground parameters on the force transmissibility between the vibrator and the ground. The numerical analyses indicate that the coupled vibration of the ground has a great influence on the dynamic response of the VGCD interaction system and further affects the output performance of the vibrator. This work could be beneficial to a more accurate evaluation of the coupling effects induced by vibrator–ground interaction.