Load distribution and dynamic response of multi-girder bridges with FRP decks

Bridges with FRP decks are gaining popularity, and there is a growing need to understand the behavior of FRP deck bridges. The characteristics of bridges with FRP decks (such as mass, stiffness, and damping) are significantly different from those of bridges with traditional concrete decks. For this reason, detailed finite element analyses are used in the present study to investigate the load distribution and the dynamic response of FRP deck bridges. The bridge–vehicle interaction based on a three dimensional vehicle–bridge coupled model is carried out on both steel and concrete multi-girder bridges. The dynamic response of bridges is obtained in the time domain considering the road roughness of the deck as a vertical excitation to the vehicles. The load distribution and the dynamic response of bridges are compared between the FRP deck and concrete deck bridges. In addition, there are some arguments whether a composite action between the deck and girders should be pursued or if a simple non-composite design should be used for FRP deck bridges. Discussions on this aspect have been made by modeling both the fully composite and partially composite FRP deck bridges.