  In this paper, a model of one-directional propagation of three-component
seismic waves in a nonlinear multilayered soil profile is coupled with a
multi-story multi-span frame model to consider, in a simple way, the
soil-structure interaction modelled in a finite element scheme. Modeling the
three-component wave propagation enables the effects of a soil multiaxial
stress state to be taken into account. These reduce soil strength and increase
nonlinear effects, compared with the axial stress state. The simultaneous
propagation of three components allows the prediction of the incident direction
of seismic loading at the ground surface and the analysis of the behavior of a
frame structure shaken by a three-component earthquake. A parametric study is
carried out to characterize the changes in the ground motion due to dynamic
features of the structure, for different incident wavefield properties and soil
nonlinear effects. A seismic response depending on parameters such as the
frequency content of soil and structure and the polarization of seismic waves
is observed.
