The present paper deals with the influence of soil non-linearity, introduced by soil liquefaction, on the soil-foundation-structure interaction phenomena. Numerical simulations are carried out so as to study an improvement method to reduce the liquefaction potential in a sandy soil profile subjected to a shaking. The efficiency of the confinement walls in the mitigation of a liquefiable soil is showed. However, the intervention at the foundation soil modifies the dynamic characteristics of soil-structure system and it seems to be an unfavorable method from the structural point of view.