Structure–Soil–Structure Interaction Analysis for Lateral Seismic Earth Pressure of Deeply Buried Structure in Layered Ground

Based on the theory of three-dimensional wave propagation, this paper proposed a method to evaluate the amplified seismic responses of two adjacent structures in horizontally stratified ground owing to seismic structure–soil–structure interaction (SSSI) and backfill soils. A guided flowchart was used to simplify the analysis for the propagation of seismic waves between adjacent substructures and their interference in the soil layers. Using the proposed method, a parametric study was performed to examine the influence of three parameters (namely, the slope of the excavation boundary, the distance between structures, and material properties of the backfill) on the amplification of seismic earth pressure on the substructures. An optimal distance between adjacent substructures was determined that conform to the minimum SSSI.