A Model for the Wave Localization in a Disordered Periodic Elevated Railway Undergoing In-Plane Vibration

摘要

In this study, a model for the analysis of the wave localization in a special kind of simply-supported beam bridge, namely, the periodic elevated railway (PER), is developed. For simplicity, each span of the PER is supposed to be composed of two longitudinal beams, a pier, and three linking springs. The standard linear solid model is employed to describe the damping of the materials of the piers and beams. Transfer matrix for each span of the PER undergoing in-plane vibration is derived, whereby the wave transfer matrix for each span is obtained. By means of the Wolf's algorithm and using the aforementioned wave transfer matrices, the localization factors accounting for wave localization in the PER are determined. With the proposed model, the influence of the disorder of the beam lengths on the wave localization in the PER is examined. Also, the interactive effect of the damping and the beam-length disorder on the wave localization in the PER is investigated. As a special case, the wave localization in a PER with rigid beam-beam-pier (BBP) junctions is also discussed in this study. Moreover, by the wave transfer matrix method, the wave localization and conversion phenomena in a finite disordered PER segment are investigated. Finally, the relation between the response of a finite disordered PER segment to external loadings and the degrees of the disorder of the PER segment is examined.