Dynamic Amplification of Traffic Loads on Road Bridges

This paper presents a new approach to the establishment of amplification factors for dynamic traffic action on road bridges. In the past, dynamic bridge–vehicle interaction has been analysed in numerous theoretical and experimental studies, which have resulted in a large variety of "dynamic amplification factor" (DAF), "impact factors" or "dynamic load allowances". The presented approach starts from the question of which cases are actually relevant for structural safety. In a rigorous manner, all relevant scenarios are considered and the various phenomena are analysed carefully. Already the qualitative analysis enables novel conclusions on the relevant scenarios and the appropriate application of amplification factors. A new domain is treated by analysing non-linear bridge–vehicle interaction at ultimate limit state (ULS). Simple models are used to draw conclusions on the governing parameters. The findings are summarised in view of the reliability assessment of existing road bridges.