A comprehensive numerical investigation has been carried out to indicate the influence of wave barriers on the complex dynamic stiffness coefficients of the surface supported foundations under dynamic loads. In the considered problems the underground is regarded as an elastic homogeneous half-space and as a layer on the top of a rigid bedrock. The results of the present numerical simulation are obtained by using the substructure approach in the frequency domain which is formulated on basis of the boundary element method (BEM). The validations of the numerical results are shown through comparison with published numerical data. The results point out that using an open trench barrier with appropriate distance surrounding the vibration source, a notable reduction level can be achieved. (c) 2006 Elsevier Inc. All rights reserved.