Relevance of a complete road surface description in vehicle-bridge interaction dynamics

A fully coupled method for reproducing road vehicle-bridge dynamic interaction is presented in which finite element models are used for the structure, multibody dynamics models for the vehicles and interaction is represented by means of a contact with the linear penalty method. This model can reproduce structure, vehicle and interaction (lift-off) nonlinearities and has been implemented within an existing finite element commercial software. With regard to road irregularities a methodology for generating pairs of parallel profiles on the same road is developed and an expression for the coherence function of road surfaces, which simplifies the generation of such profiles, is proposed. These methods are applied to two different bridges. Results show the relevance of considering a complete surface definition when dynamic response of road bridges and vehicles is analysed. Bridge traffic-induced dynamic behaviour is the main issue in this study; attention is also paid to the vehicle vibration as it is also influenced by the road surface description. Lift-off model capabilities are shown by considering a bump on the bridge surface.