A procedure will be developed for the analysis of dynamic response and noise transmission of large structural systems of finite length which are composed of discretely periodic units. The method is a combination of finite elements, transfer matrices and waved propagation. The response is treated as superposition of wave motions using wave reflection (due to changes in the construction pattern) and transmission matrices. This enables the computations to proceed in the direction of wave propagation only, so that the results are always numerically stable. The new method can treat long piece-wise periodic stiffened structures of finite length, which is not possible with traditional transfer matrices, because of numerical difficulties. The method can use the finite element formulation for the periodic units to treat systems of complicated geometries and is expected to be much faster than the finite elements because the degrees of freedom are reduced. The method will be used for the prediction of the structure-borne noise transmission of large flexible structures. Finally, the method will be used with the stochastic finite element formulation to reduce computational time, which is an evident problems in stochastic response as the number of elements increases. //
