A model for the dynamic response of a defected periodic bridge with PSWS coupling.

Abstract: In this study, a numerical model is developed to investigate the dynamic response of a defected periodic bridge (DPB) when considering pile–soil–water–structure (PSWS) interaction. In order to determine the dynamic response of the DPB, the DPB is decomposed into three parts – left and right semi-infinite periodic bridges and the defected span. To account for the coupling between the superstructure of the bridge and the pile foundations, a coupled boundary element method (BEM) model is used to model the pile–soil–water (PSW) interaction. By using the PSW BEM model, the transfer matrices for the pier and beam, the joint condition at the beam–beam–pier (BBP) junction, the response of the DPB to the characteristic wave is obtained. To investigate the relation between the response of the DPB and the defect state of the corresponding super-cell, the super-cell method is developed for the DPB. Numerical results for the energy bands of the super-cell show that the defected span of the DPB may give rise to additional passband frequencies, namely, the defect state frequencies. Moreover, when the DPB is subjected to a characteristic wave with frequency equal to the defect state frequency, resonance may occur and the response of the DPB corresponding to the resonance is localized around the defected span. [Copyright &y& Elsevier]