ABSTRACT
In the present contribution the dynamic behaviour of railway bridges, modelled as simply-supported beams, is addressed. In particular, the effect of Soil-Structure Interaction (SSI) on the resonant response of the aforementioned structures in investigated. To this end, a 3D coupled Boundary Element-Finite Element (BEM-FEM) model integrated in the time domain is implemented. First, a set of bridges is defined covering the lengths and frequencies usually associated with high transverse vibration levels. A single soil layer is considered with shear wave velocities in the interval 150–365 m/s. Then a parametric analysis is performed in order to determine the static response of the bridge-soil systems, the fundamental frequency and the maximum response in free vibration left by the passage of a single moving load. From this analysis the influence of soil-structure interaction on cancellation velocities and maximum free vibration amplitudes is investigated in detail.
