ABSTRACT
The use of 1-D numerical models in seismic analyses requires a special care since the plastic shear strains in the soil are linked with the plastic volumetric strains. This aspect is naturally taken into account in 3-D models and 1-D/2-D geometry models with three-dimensional kinematics. In this paper, we present the combined effects of the different components of motion on the overall soil response. It is particularly shown that the decomposition of seismic body waves, in view of separate analyses, is not possible beyond the elastic strain domain because of the coupling between the components of the plastic strain tensor.
