Dynamic Soil–Structure–Equipment Interaction (I): Closed-Form Analytical Solution for Incident Plane SH wave Based on Rigid Foundation Model

Abstract

ABSTRACT Soil–structure–equipment interaction is investigated using a two-dimensional (2D) whole model of soil–structure–equipment interaction with rigid foundation embedded in a homogenous half-space. A closed-form analytical solution is presented for the model response to incident plane SH wave based on wave function expansion method, and the accuracy of the solution is verified by comparison with published results. The analysis focuses on the effects of soil–structure interaction (SSI) on the response of structure–equipment interaction. The results show that SSI has significantly influence the response of structure–equipment interaction. The traditional fixed base model of structure–equipment interaction may not reflect the response of structure–equipment interaction properly. After considering the effect of SSI, the peak effective input motion of structure–equipment system is magnified 35.5% than that of fixed base model, and the structure relative response and the equipment relative response are all smaller. The peak relative response of structure and that of the equipment are highly dependent on the equipment–structure frequency ratio and mass ratio. Especially, the peak of equipment relative response will tend to linear increase, instead of rapid decreasing when the equipment–structure frequency ratio is in the range of 0.5 ~ 1.0. Although the model of this paper is simple, it may be helpful to obtain insight into the effects of SSI on structure–equipment interaction and provide a comparison for the further research about soil–structure–equipment interaction with flexible foundation.