Modelling of Steel-Concrete Bridges Subjected to a Moving High-Speed Train

In the present study, a method for modelling and simulating the transient vibrations of a system comprising a steel-concrete bridge, ballasted track and moving high-speed train is proposed.The proposed approach uses advanced LS-DYNA simulation software based on finite element (FE) analysis and is applied to a series of single-span simply supported steel-concrete bridges.The theoretical span lengths of the bridges are 15, 18, 21, 24 and 27 metres.The bridge-track-train system is assumed to be fully symmetric.The reinforced concrete platform is homogenized based on the quasi-uniform distribution of the rebars in the specified sections.The bridge FE model does not include transverse bracing between the steel main beams, and the track rail-line axes are rectilinear.The ICE-3 highspeed multiple-unit train is considered at service velocities ranging between 200 and 300 km/h.FE analysis reveals deflection of the bridge at mid span.The results are plotted as a function of train velocity, thus permitting an assessment of the dynamic response of the bridge for each span length.