Assessment of simplified numerical models for vehicle-bridge dynamic interaction

The main objective of the presented study is to review and evaluate simplified finite element (FE) models used for dynamic vehicle bridge interaction studies. The simplified models considered have been developed using new features implemented in LS-DYNA for computer simulation of moving loads. This new modeling approach offers a balance between computational efficiency and accuracy, and is especially useful for extensive parametric studies on dynamic response of bridges induced by traffic loading. Models for a simply supported beam subjected to a moving mass and one-axle vehicle with spring and damper respectively are used to verify the corresponding FE algorithm through comparison between FE results and existing analytical or semi-analytical solution obtained from MATLAB procedure. In addition, a more complex FE model for a girder-slab-barrier bridge, coupled with a heavy truck, is developed based on experimental data. After validation of FE models, sensitivity of dynamic amplification factor (DAF) to vehicular parameters including: velocity, weight ratio of vehicle over the bridge, and damping of the vehicle is investigated. DAF was found to be generally ascending with growing velocities and local peaks occurring at certain velocities.