An Energy Transmitting Boundary for Semi-Infinite Structures

Abstract

AbstractA soil-structure system associated with a semi-infinite structure such as tunnel or pavement is usually investigated by finite element analysis. If the boundary of the finite element model selected is not far enough from the excitation source or does not have an appropriate energy-absorption mechanism, it may introduce a significant error induced by reflected waves. This study develops a structural transmitting boundary to absorb the transmitting energy at the boundary of the analytical model. The structure is divided into finite and semi-infinite regions. The stiffness of the semi-infinite region is established by the principle of virtual work and applied at the transmitting boundary. The comparisons of the structural displacements induced by vertical harmonic excitations show that the analytical model size can be significantly reduced, if the proposed transmitting boundary is used to simulate the semi-infinite structural region.