Bridge Dynamics and Loading

Recent UCD research on dynamic bridge-truck interaction and bridge traffic loading in general is reported. The accuracy of bridge traffic load assessment has been significantly improved by identifying the differences in the sources of traffic loading on short- to medium-span bridges and treating them separately. It is shown that results can be significantly improved by treating 1-, 2-, 3- and 4-truck loading events separately. Gaps between trucks are also identified as a critical issue that strongly influences the frequency of key 3- and 4-truck events. Trends in the dynamics of traffic loading are identified using simple force models on simply supported beams. It is shown that an accurate assessment of the influence of dynamics requires a probabilistic approach. This is illustrated through an assessment of the dynamic factor for a bridge in Slovenia