Dynamic analysis of vehicle-bridge interaction using the substructure approach

In this paper, a substructure approach for the dynamic analysis of railway bridges is presented. The basic idea consists in treating the running train, the track and the bridge deck as three substructures. The equations of motion of the coupled vehicle-track-bridge system are derived by applying a particular variant of the Component-Mode Synthesis method which allows the condensation of the axle degrees-of-freedom into those of the rails in contact, properly accounting for the interaction among the three sub-systems. The procedure proves to be extremely versatile and provides results in good agreement with those obtained by finite element codes despite the computational burden is substantially reduced.